Study on wireless charging technologies : final report.
Date: 2024-06-05
Institutions: Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs
Subjects: electrical equipment, electricity storage device, electronic device, electronic waste, harmonisation of standards, market supervision, marketing standard, mobile phone, radio telecommunications, report, sustainable development, technical standard

Study on wireless charging 
technologies 

Service Contract GROW/2023/MVP/0037 

Final Report 

Prepared by  
KPMG 
May 2024 

 
 
EUROPEAN COMMISSION 

Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs 
Directorate H — Ecosystems III: Construction, Machinery and Standardisation 
Unit H.2 — Machinery & Equipment 

Contact:  Alexis Basiaux 

E-mail: alexis.basiaux@ec.europa.eu 

European Commission 
B-1049 Brussels 

 
 
EUROPEAN COMMISSION 

Study on wireless charging 
technologies 
Service Contract GROW/2023/MVP/0037 

Final Report 

Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs 

2024 

Study on wireless charging technologies 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
EUROPEAN COMMISSION 

Manuscript completed in June 2024 

1st edition 

This document has been prepared for the European Commission however it reflects the views only of the 
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Luxembourg: Publications Office of the European Union, 2024 

© European Union, 2024 

The reuse policy of European Commission documents is implemented by Commission Decision 
2011/833/EU of 12 December 2011 on the reuse of Commission documents (OJ L 330, 14.12.2011, p. 39). 
Unless otherwise noted, the reuse of this document is authorised under a Creative Commons Attribution 
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PDF 

ISBN 978-92-68-16609-3 

doi:10.2873/371485  ET-09-24-365-EN-N 

Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs 

2024 

Study on wireless charging technologies 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Study on wireless charging technologies 

Contents 

Glossary ............................................................................................................ 7 

List of Abbreviations ...................................................................................... 10 

List of Figures ................................................................................................. 11 

List of Tables .................................................................................................. 12 

Abstract ........................................................................................................... 13 

Résumé ........................................................................................................... 14 

Executive summary ........................................................................................ 15 

Résumé analytique ......................................................................................... 20 

1. 

Introduction ............................................................................................ 26 

1.1.  Context of the study ............................................................................. 26 

1.2.  Objectives ............................................................................................ 27 

1.3.  Content of the study ............................................................................. 29 

2.  Methodology ........................................................................................... 30 

2.1.  Desk research and literature review .................................................... 30 

2.2.  Product Database ................................................................................ 31 

2.3.  Stakeholder interviews ......................................................................... 35 

2.4.  Market analysis .................................................................................... 38 

2.5.  Voice of the Customer ......................................................................... 40 

3. 

Technical overview ................................................................................ 42 

3.1.  Typology and definition of wireless charging solutions ........................ 42 

5 

Study on wireless charging technologies 

3.2.  Wireless charging classification ........................................................... 46 

3.2.1.  Distance of transfer .................................................................................. 47 
3.2.2.  Main technologies .................................................................................... 49 
3.2.3.  Standards ................................................................................................. 53 
3.2.4.  Proprietary technology, new standards and coexistence of standards .... 60 

4.  Market overview ..................................................................................... 66 

4.1.  Regulatory background ........................................................................ 66 

4.2.  Market size overview ........................................................................... 67 

4.2.1.  Market size estimations ............................................................................ 68 
4.2.2.  Sector size estimations ............................................................................ 70 
4.2.3.  Key factors affecting market growth ......................................................... 71 

4.3.  Voice of the Customer ......................................................................... 81 

5.  Product overview ................................................................................... 84 

5.1.  Wireless charging transmitters ............................................................. 84 

5.1.1.  Transmitters (standalone and embedded) ............................................... 84 
5.1.2.  Add-on receivers ...................................................................................... 93 

5.2.  Device categories ................................................................................ 93 

5.2.1.  Low power electronics .............................................................................. 94 
5.2.2.  Medium-high power electronics ................................................................ 99 
5.2.3.  Other electronic devices ......................................................................... 106 

6.  Overview of energy efficiency, charging performance and 

interoperability aspects ....................................................................... 108 

6.1.  Technical overview on energy efficiency, charging performance and 

interoperability focusing on inductive charging .................................. 108 

6.2.  Experiment......................................................................................... 116 

6.2.1.  Technical structure of the experiment .................................................... 116 
6.2.2.  Device and transmitter selection ............................................................ 117 
6.2.3.  Data collection ........................................................................................ 119 
6.2.4.  Results ................................................................................................... 122 

7.  Conclusion ........................................................................................... 137 

8.  Appendix .............................................................................................. 138 

8.1.  Bibliography ....................................................................................... 138 

8.2.  Annex I. – Indicative guide for stakeholder interviews ....................... 149 

6 

 
Study on wireless charging technologies 

Glossary 

AirFuelAlliance 

AirCord (Wi-Charge)  AirCord, developed by Wi-Charge, is a technology that utilises 
infrared  beams  to  transmit  several  watts  of  energy  wirelessly 
over distances of several meters, powering compact receivers 
integrated  into  IoT  devices  and  electronics.  These  diminutive 
receivers  efficiently  convert  infrared  energy  into  electrical 
energy, powering the devices they're embedded in. 
Created  in  2015  after  the  merging  of  PMA  and  A4WP,  the 
AirFuel  Alliance  is  a  non-profit  global  coalition  of  companies 
working  on  the  creation  of  wireless  charging  standards  and 
main competitors of the Qi standards. The Alliance has certified 
standards for resonant (AirFuel Resonant) and since January 
2024,  also  a  newly  launched  RF  wireless  charging  standard 
specification (Airfuel RF). 
The  directive  amends 
the  Radio  Equipment  Directive 
2014/53/EU  and  requires,  among  others,  several  hand-held 
electronic  devices  sold  from  28  Dec  2024  onward  to  be 
equipped and be able to charge via a USB Type-C port. 
The  annualised  average  rate  of  growth  between  two  given 
years,  assuming  growth  takes  place  at  an  exponentially 
combinedrate. 

Common Charger 
Directive  
(EU 2022/2380) 

Compound Annual 
Growth Rate 

Daily unique visitors   Daily  unique  visitors  is  the  average  number  of  individuals 

Energy harvesting 

External Power 
Supply  

Gallium nitride  

IoT 

NFC 

visiting the analysed web domain in one day. 
Energy harvesting is the process of capturing and converting 
ambient energy from sources such as solar, thermal, vibration, 
or radio waves into electrical energy, which can then be used 
to power electronic devices, enabling them to operate without 
an external power source or with minimal battery use. 
External  power  supplies  are  power  adaptors  used  to  convert 
household electric current into lower voltage (AC) current - or 
DC  current  -  in  order  to  operate  a  large  variety  of  household 
and office products. 
Gallium  nitride  (GaN)  is  a  very  hard,  mechanically  stable 
semiconductor.  With  higher  breakdown  strength, 
faster 
switching  speed,  higher  thermal  conductivity  and  lower  on-
resistance,  power  devices  based  on  GaN  significantly 
outperform  silicon-based  devices.  GaN  power  devices  in  Qi-
enabled  wireless  charging  provide  faster  charging  times  and 
more efficient power transfer 
IoT  stands  for  Internet  of  Things  and  refers  to  the  collective 
network  of  connected  devices  and  the  technology  that 
facilitates  communication  between  devices  and  the  cloud,  as 
well as between devices themselves. 
Near Field Communication (NFC) is a communication protocol 
between two electronic devices at a short range. This is usually 
done  through  specific  antennas.  Currently,  an  option  for 

7 

NFC Forum 

Power by Contact  

Predecessor Study 

Product Database 

Qi  

RF 

Study on wireless charging technologies 

wireless  charging  based  on  this  technology  is  backed  by  the 
NFC Forum. 
The NFC Forum is a non-profit industry association working on 
sharing  development,  application  and  marketing  expertise 
between  members  concerning  near  Field  Communication 
technologies.  It  is  currently  maintaining  an  NFC  wireless 
charging standard for low power devices. 
transfer  solution  developed  by 
A  conductive  power 
Energysquare.  Unlike  inductive  charging,  the  technology 
operates  through  direct  contact  between  a  transmitter  and 
receiver. 
The  ”Technical  supporting  study  to  assess  the  status  of 
wireless  charging  technologies  used  for  mobile  phones  and 
similar  portable  equipment  and  next  expected  main 
technological developments” - A technical study commissioned 
and  published  by  the  European  Commission  in  2021,  which 
serves as a precursor to the current regulatory efforts aimed at 
analysing charging interfaces and communication protocols for 
wireless  charging  technologies.  This  study  was  conducted  to 
assess  the  wireless  charging  market's  current  state,  identify 
key  technical  aspects  of  interoperability,  and  define  an 
appropriate product scope.  
The  Product  Database  is  a  compiled  collection  of  technical 
information sourced from literature, market statistics, and desk 
research  within  the  wireless  charging  sector.  It  serves  to 
technological  solutions  and 
identify  widely  accepted 
requirements by reviewing documentation of various products, 
categorised into three main types: Transmitters, Devices, and 
Add-on  receivers.  This  database  aids 
in  understanding 
prevalent trends and requirements within the wireless charging 
market. 
The Qi standard is a universal and open standard for wireless 
charging  developed  by  the  Wireless  Power  Consortium.  It 
enables comptaible devices to connect to Qi certified chargers 
from any manufacturer. Qi was first released in 2010 and has 
since been incorporated into numerous smartphones, tablets, 
and  other  devices.  As  of  December  2023,  there  are  351 
manufacturers  working  with  the  standard,  including  Apple, 
Asus, Google, Huawei, LG Electronics, Samsung, Xiaomi, and 
Sony.  In  January  2023,  the  consortium  announced  Qi2,  an 
update  to  the  existing  standard,  which  includes  a  magnetic 
connection  based  on  Apple's  MagSafe  technology.  The  Qi2 
standard  was  released  on  April  19,  2023,  by  the  Wireless 
Power Consortium. 
Radio Frequency (RF) wireless charging is a type of uncoupled 
wireless  charging  in  which  an  antenna  embedded  in  an 
electronic device can pick up low level radio frequency waves 
from external sources and convert the waves' energy to direct 
current voltage. 

8 

Receiver (Rx) 

Transmitter (Tx) 

U.S. Department of 
Energy 

USB Type C 

Voice of the 
Customer  

Wireless Power 
Consortium  

Wireless Power 
Transfer  

Study on wireless charging technologies 

Secondary  part  of  the  Wireless  Power  Transmission  (WPT) 
system,  comprising  the  combination  of  a  coil  or  antenna, 
communication device and/or energy storage in one housing. 
This  is  the  part  that,  under  the  influence  of  (usually)  an 
electromagnetic field created by a compatible transmitter, will 
get a current generated and charge the device. The receiver is 
most  commonly  embedded  in  the  device  to  be  charged, 
although add-on receivers with USB connectors do also exist. 
Primary  part  of  the  Wireless  Power  Transmission  (WPT) 
system,  a  combination  of  a  coil  or  antenna,  communication 
device and/or connection to an energy supply. This is the part 
able to create (usually) an electromagnetic field that will induce 
further current in a receiver and will as well control the energy 
transfer. The transmitter can be either standalone or embedded 
in another product like furniture or vehicles. 
As  a  body  of  the  Federal  Government,  the  Department  of 
Energy  manages  the  United  States'  energy  and  nuclear 
infrastructure and administers the country's energy policy. The 
Department of Energy also funds scientific research in the field. 
USB-C is a cable connection type standard designed to replace 
all  USB  (Universal  Serial  Bus)  types  on  the  computer  and 
device ends of future USB with a single reversible connector. 
USB-C  allows  for  peripheral  connectivity  of  USB  devices  at 
speeds power outputs of USB 3.1 (up to 10Gbps and 20v @ 
5A). 
Voice  of  the  Customer  (VoC)  is  a  term  that  describes  the 
customer's 
their  experiences  with  and 
feedback  about 
expectations for certain products or services 
Wireless  Power  Consortium  (WPC)  is  an  open  standards 
development  organisation  that  works  with  electronic  and 
technology  companies  across  the  world.  Their  mission  is  to 
enable  consumers  to  enjoy  the  convenience  and  benefits  of 
wireless  power  by  establishing  global  standards  for  safety, 
efficiency and interoperability. 
Wireless Power Transfer (WPT), often referred to as wireless 
charging, stands for the transmission of electrical energy from 
a power source to an electrical load via electric and or magnetic 
fields or waves between a primary and a secondary device. Its 
main elements are the transmitter (Tx) and the receiver (Rx). 
There  are no cables involved in  the  power transmission from 
Tx to Rx, however, the connection of the Tx to the EPS might 
require wires. 

9 

Study on wireless charging technologies 

List of Abbreviations 

A 
AET 
BPP 
CAGR 
CPT 
DOE 
EMI 
EPP  
EPS 
EV 
EU 
GaN 
GHZ 
IoT 
IPT 
kHz 
kWh 
LPT 
MHz 
MPP 
MRPT 
mW 
MW 
NFC 
PD 
PT 
RF 
RFPT 
RQ 
Rx 
THz 
Tx 
USD 
V 
VoC 
W 
WPC 
WPT 

Ampere  
Acoustic Energy Transfer  
Baseline Power Profile  
Compound Annual Growth Rate 
Capacitive Power Transfer 
U.S. Department of Energy  
Electromagnetic Interference  
Extended Power Profile  
External Power Supply  
Electric vehicle 
European Union 
Gallium nitride  
Gigahertz 
Internet of Things 
Inductive Power Transfer 
Kilohertz 
Kilowatt-hour 
Laser Power Transfer 
Megahertz 
Magnetic Power Profile  
Magnetic Resonance Power Transfer 
Milliwatt 
Megawatt 
Near Field Communication 
Product database 
Power Transfer 
Radio Frequency  
Radio Frequency Power Transfer 
Research Question 
Receiver 
Terahertz 
Transmitter 
U.S dollars 
Volt 
Voice of the Customer  
Watt 
Wireless Power Consortium 
Wireless Power Transfer 

10 

Study on wireless charging technologies 

List of Figures 

Figure 1 – KPMG-Gutti Wireless Charging Efficiency Index ............................. 18 

Figure 2 – Indice d'efficacité de la recharge sans fil KPMG-Gutti ..................... 24 

Figure 3 – Scheme of a wireless charging system ........................................... 45 

Figure 4 – The relationship between distance and power level illustrated by       
Airfuel RF technology ....................................................................................... 48 

Figure 5 – Size of wireless charging market worldwide from 2020 to 2030 ...... 68 

Figure 6 – Wireless charging transmitter and receiver unit shipments            
worldwide in 2020, 2025 and 2030 ................................................................... 70 

Figure 7 – Wordcloud from negative customer reviews .................................... 82 

Figure 8 – Wireless charging pads sold worldwide 2023, by retail price ........... 86 

Figure 9 – Share of supported technologies for transmitters ............................ 88 

Figure 10 – Connector types of standalone transmitters* ................................. 90 

Figure 11 – Supported wireless charging technologies among smartwatches . 98 

Figure 12 – Average price comparison of wireless capable and non-wireless   
capable products from Xiaomi and Samsung ................................................. 103 

Figure 13 – Existing standards in the medium-high power category .............. 105 

Figure 14 – Energy efficiency factors ............................................................. 110 

Figure 15 – Basic components of the IPT system .......................................... 112 

Figure 16 – Qi communication protocol process ............................................. 115 

Figure 17 – Schematic technical structure of the experiment ......................... 117 

Figure 18 – Wired and wireless charging time comparison ............................ 127 

Figure 19 – KPMG-Gutti Wireless Charging Efficiency Index ......................... 129 

Figure 20 – KPMG-Gutti Wireless Charging Efficiency Index ......................... 132 

11 

Study on wireless charging technologies 

List of Tables 

Table 1 – Reviewed literature by type .............................................................. 31 

Table 2 – Product Database data structure ...................................................... 34 

Table 3 – Product database summary .............................................................. 35 

Table 4 – List of conducted interviews .............................................................. 35 

Table 5 – Full summary of contacted organisations ......................................... 37 

Table 6 – Main wireless charging technologies ................................................ 47 

Table 7 – Global wireless charging market size estimations ............................ 69 

Table 8 – Summary of the main pain points and positive experiences ............. 80 

Table 9 – Share of supported technologies for transmitters ............................. 87 

Table 10 – Supported standards by input power level ...................................... 89 

Table 11 – Connector types of standalone transmitters ................................... 90 

Table 12 – Number charging pads in standalone transmitters .......................... 91 

Table 13 – Embedded device type summary .................................................... 92 

Table 14 – Technology supported by add-on receivers .................................... 93 

Table 15 – Supported wireless charging technologies - low power electronics 97 

Table 16 – The proportions of wireless capable medium-high power devices 102 

Table 17 – Share of supported technologies for medium-high power devices 103 

Table 18 – Existing standards in the medium-high power category ................ 104 

Table 19 – Smartphones’ input power level summary .................................... 105 

Table 20 – Summary of existing standards in other products category .......... 106 

Table 21 – Products used for the experiment  ................................................ 119 

Table 22 – Recorded and calculated variables ............................................... 120 

Table 23 – Result of interoperability test for scenarios examined ................... 122 

Table 24 – Average charging power and charging time ................................. 124 

Table 25 – Provided power and charging power ............................................ 124 

Table 26 – Charging time of scenarios tested ................................................ 125 

Table 27 – Energy efficiency of scenarios tested ........................................... 125 

Table 28 – Average input power and average charging power....................... 130 

Table 29 – Comparison of wireless chargers .................................................. 131 

Table 30 – Standby loss for transmitters ........................................................ 133 

Table 31 – Average temperature during the charging process ....................... 134 

Table 32 – Average temperature in different scenarios .................................. 135 

12 

 
Study on wireless charging technologies 

Abstract  

The Study reviews the current state of wireless charging technologies for mobile 
phones and similar portable consumer electronics compared to the state depicted 
by the Predecessor Study from 2021, with the following assumptions: 

•  Qi has predominance on the mobile phone market; 

•  Alternative approaches and technologies are still not present; 

•  No remarkable competition exists amongst standards ; 

•  There is a constant strive for development; 

•  Technological limitations have not yet been resolved . 

The  Study  combines  findings  of  desk  research,  literature  review,  a  product 
database,  expert  interviews,  and  measurement  experiments,  to  analyse  market 
trends, technological advancements, and user experiences. 

Key  findings  reveal  that  while  adoption  of  wireless  charging  in  products  is  still 
small  at  present,  there  is  a  steady,  ongoing  market  growth  fueled  by  consumer 
electronics, particularly smartphones. While the Qi standard dominates mobile phones, 
other consumer electronics lag  mostly due to form factor constraints and  the use of 
proprietary  solutions.  Wireless  charging  still  faces  substantial  barriers,  such  as 
reduced energy efficiency, interoperability, charging speed, increased alignment 
issues,  and  environmental  sustainability.  Despite  advancements,  expert 
consensus signals an early stage in wireless charging evolution. Due to the absence 
of a universal solution, notable innovation and considerations of standardisation exist; 
the latter will ultimately shape future trajectory. 

13 

Study on wireless charging technologies 

Résumé  

L’étude  analyse  l'état  actuel  des  technologies  de  recharge  sans  fil  pour  les 
téléphones mobiles et les appareils électroniques portables, comparativement à 
l'état décrit par l'étude de 2021, sur base des hypothèses suvantes: 

• 

• 

• 

• 

• 

La norme Qi domine le marché de la téléphonie; 

Il n’existe pas encore d'pproches ni de technologies alternatives; 

Il n’existe pas de concurrence notable entre les normes; 

Il y a un effort constant de développement; 

Certaines limitations technologiques n’ont pas encore été résolues. 

L'étude associe recherche documentaire, analyse de la littérature et d’une base 
de données, des entretiens avec des experts, et des expériences de mesure, pour 
analyser les tendances du marché, les avancées technologiques et les expériences 
des utilisateurs. 

Si  l’adoption  de  la  recharge  sans  fil  est  encore  limitée,  le  marché  croît 
régulièrement,  alimenté  par  l'électronique  grand  public,  dont  les  smartphones.  La 
norme  Qi  domine  la  téléphonie,  mais les  autres produits  électroniques  grand public 
sont  retardés  par  des  contraintes  et  par  l'utilisation  de  solutions  propriétaires. 
restent :  une  efficacité  énergétique  moindre,  une 
D’importants  obstacles 
interopérabilité  limitée,  des  vitesses  de  recharge  accrues,  des  problèmes 
d'alignement et de durabilité environnementale. D’après les experts, la recharge 
sans fil en est à ses débuts. En l'absence d'une solution universelle, des innovations 
et des efforts de normalisation existent et cela façonnera la trajectoire future. 

14 

Study on wireless charging technologies 

Executive summary 

The Present Study (the Study) aims to review the current state of wireless charging 
technologies for mobile phones and similar portable consumer electronics compared 
to  the  state  depicted  by  a  Predecessor  Study  from  2021,  with  the  following 
assumptions: 

•  The predominance of Qi on the mobile phone market has remained 

unchanged or even increased.  

•  Alternative  approaches  and  technologies  like  RF  charging  are  still  not 
present on the consumer market, which undermines the prevalence of the Qi 
standard.  

•  Regarding  standards,  no  remarkable  competition  can  be  seen  on  the 
market, nor an emerging competitor of the Qi standard for the mobile phone 
market.  

•  There  is  a  constant  strive  of  development  in  the  industry,  especially 
concerning  power  levels,  charging  speed,  alignment  issues  and  energy 
efficiency.  

•  Technological  limitations  like  form  factor  have  not  been  resolved  yet, 

leading to organic market fragmentation for different device types. 

The Study aims to analyse the wireless charging market's current state and changes, 
with a focus on potential future harmonised charging solutions for legislative directives. 
Various research methods were combined to provide a coherent overview of the 
wireless  charger  market  and  to  feed  potential  legislative  actions.  Initially,  a 
comprehensive desk research and literature review was conducted to understand 
the landscape of the wireless charging market. This phase aimed to map out the latest 
to  previous  studies. 
technological  developments  and  changes  compared 
Subsequently,  a  detailed  product  database  was  created,  capturing  technical 
information on wireless charging technologies across various products. This database 
served  as  a  crucial  resource  for  analysing  market  developments  and  product 
specifications. Additionally, structured expert interviews were conducted with industry 
stakeholders to gather insights into market changes, technological advancements, and 
customer  experiences,  and  to  explore  various  aspects,  including  market  overview, 
landscape,  technologies,  customer  perspectives,  and  standardisation  opportunities. 
Using  data  collected  from  the  different  sources,  a  thorough  market  analysis  was 
performed,  focusing  on  identifying  trends,  market  shares,  penetration  rates,  and 
fragmentation within the wireless charging market. 

Additionally,  special  attention  was  given 
to  energy  efficiency,  charging 
performance,  and  interoperability  in  wireless  charging  solutions  relevant  for  the 
scope  of  the  present  Study.  Above  combining  literature  review  findings  and  expert 
insights, a measurement experiment was conducted with multiple wireless chargers 

15 

Study on wireless charging technologies 

and wireless charging capable devices to provide a comprehensive understanding of 
these aspects. As the market anyalysis revealed that regarding consumer electronics, 
no  other  technologies  are  widely  applied  on  the  consumer  market  than  inductive 
charging, this is the only technology which could be effectively assessed from energy 
efficiency and interoperability aspects. Concerning other technologies, only high-level, 
if  any  sources  could  be  found  which  specify  on  these  subjects  for  consumer 
electronics, and there were no products available on the market which could have been 
tested for empirical findings. 

The  emergence  of  wireless  charging  technologies  could  promise  an  age  of 
convenience  and  aesthetic  simplicity  for  recharging  electronic  devices  while  also 
narrowing  the  gap  between  the  energy  efficiency  of  wireless  and  wired  charging. 
However,  findings  of  the  present  Study  show  that  the  current  landscape  is 
characterized by ongoing developments,  as  present  solutions  still  lack  to  fully  or 
even partially serve customer needs and convenience. Therefore, further innovative 
effort  is  required  to  not  only  enhance  user  experience  but  also  to  maximise  energy 
efficiency in wireless charging systems.  

The  wireless  charging  market,  valued  at  17.5  billion  U.S.  dollars  in  2021,  is 
experiencing  a  notable  25.7%  year-on-year  growth  trajectory  (Compound  Annual 
Growth  Rate,  CAGR).  Projections  suggest  it  will  reach  185.9  billion  U.S.  dollars  by 
2030. This growth is primarily driven by the consumer electronics device category, 
with the total smartphone market (including devices not capable of WPT) being by far 
the largest, reaching 467.6 billion U.S. dollars in 2024. However, it is worth noting that 
only  13%  of  smartphone  models  currently  feature  wireless  charging  capability, 
indicating  substantial  room  for  expansion.  Additionally,  on  the  transmitter  side,  the 
consumer  wireless  transmitter  sector  is  valued  around  3.8  to  4.5  billion  U.S. 
dollars in 2024, with an expected 3.6% CAGR by 2030. The global in-car wireless 
charger  market  is  growing  steadily,  with  a  projected  CAGR  of  4.72%  from  2020  to 
2027, driving the adoption of embedded solutions. In 2022, the market was valued at 
around 1.93 billion U.S. dollars and is forecasted to reach 2.55 billion U.S. dollars by 
2030. 

Nonetheless, the technological landscape is riddled with fragmentation. There is no 
universal solution that caters to all devices uniformly, and specialists in the field 
are skeptical of seeing such a solution arise given the present state of affairs. So far, 
this has fostered a natural market segmentation based on the physical attributes 
of devices. 

Findings from  the  collected product  database  show  that  the  Qi standard,  a form  of 
inductive  charging,  has  become  predominant  in  the  subcategory  of  mobile 
phones, resulting in a de facto standard through organic adoption by the industry. The 
evolution and clustering of various inductive standards into newer versions of the Qi 
standard  showcases  effort  to  improve  efficiency  and  user  convenience  with 
features  like  magnetic  alignment.  However,  the  form  factor  of  Qi  restricts  its 
applicability 
to  other  categories  of  devices,  currently  disfavoring  its  use  in 
smartwatches and other consumer electronics beyond mobile phones, where wireless 

16 

Study on wireless charging technologies 

charging  presently  does  not  hold  a  dominant  status.  The  experiment’s  compatibility 
test also showed high level of interoperability between smartphones due to Qi (and Qi 
+  Proprietary)  solutions.  On  the  other  hand,  less  interoperability  could  be  observed 
among smartwatches tested, even in the case of Qi certified products, potentially due 
to their shape. 

For alternative product categories, Qi's dominance is not mirrored, as indicated 
by very small adoption rates. While new applications are emerging for product classes 
like  smart  toys,  furniture,  and  various  other,  these  consumer  electronics  categories 
have yet to fully embrace wireless charging and often use proprietary solutions, partly 
due to custom designs and a lack of clear consumer benefits that drive market demand. 
The findings also suggest that wireless charging with Qi is mainly implemented with 
smartphones due to their suitable shape and size, while neither adoption for smaller 
nor for larger sized consumer electronics has been solved to this date in a technically 
and economically feasible way. 

Based on the experiment results, wired charging maintains superiority over wireless 
alternatives across all parameters, such as charging time, charging power and energy 
efficiency.  Such  observations  of  the  experiment  could  confirm  the  insights  of  the 
literature review, namely the limitations of wireless charging solutions and the reasons 
for relatively slower uptake of wireless technologies. 

Despite its convenience, wireless charging still faces substantial barriers that need to 
be  addressed  through  continued  innovation  and  consumer  education.  Reduced 
energy  efficiency  and  resulting  decrease  in  environmental  sustainability,  low 
levels  of  interoperability  and  charging  speed,  as  well  as  increased  alignment 
issues continue to influence the technology's market potential. The promise of truly 
wireless charging could be perceived as unfulfilled by customers seeking more spatial 
freedom  which  is  currently  limited  by  tight  coupling  and  alignment  requirements. 
Moreover,  while  inductive  charging  systems  have  made  strides  in  availability, 
particularly in the automotive and consumer electronics sectors, other technologies 
like RF charging are still in developmental stages and lack market penetration 
on the consumer market. 

Difference in energy efficiency between wired and wireless charging derives from the 
power  transfer  between  transmitter  and  receiver.  In  case  of  inductive  charging,  the 
amount  of energy  loss  depends  on several factors  of  the wireless  charging  system, 
such as alignment, distance, shape and resistance of coils or frequency used. With the 
factors  influencing  each  other,  efficiency  can  only  be  determined  for  the  complete 
charging  system  embracing  the  EPS,  cables,  transmitter,  receiver  and  the  device. 
Nevertheless, sources in the literature review have agreed that the energy efficiency 
level  of  inductive  charging  is  falling  within  the  50-80%  interval.  Furthermore, 
additional energy  loss  compared to  wired chargers  could occur due  to  standby  loss 
and heat generation as well which should be also taken into consideration during the 
analyses of standardisation potential.  

17 

Study on wireless charging technologies 

The  conducted  experiment  underlined  the  findings  of  the  Study,  while  also 
indicated  interesting  interrelations  between  various  wireless  chargers  and  devices. 
Brand-to-brand  scenarios  were  the  top  performers  in  terms  of  all  investigated 
aspects (charging power, charging time, energy efficiency). Despite the compatibility 
of  smartphones  and  transmitters,  customers  could  experience  notable  gaps  in  the 
products’  performance  (e.g.  two  hours  difference  in  charging  time).  Additionally, 
misalignment causes decrease between 9 to 23 % points in energy efficiency. In 
order  to  provide  a  comprehensive  metric  of  overall  charging  efficiency,  the  Study 
introduced the KPMG-Gutti Wireless Charging Efficiency Index which is evaluating 
and ranking wireless charging scenarios compared to their wired counterpart.  

The KPMG-Gutti Index’s maximum value (1) means that the given wireless charging 
method  is  equally  efficient  as  its  wired  charging  counterpart.  Scenarios  where 
smartphones were charged by transmitters of the same brand were the top performers 
based on their Index score (from 0,34 to 0,68). Additionally, scenarios without brand 
arrangement  have  ~50%  lower  score  on  average,  indicating  differences  between 
scenarios  and  brand  arrangement’s  substantial 
impact  on  overall  charging 
performance. 

Figure 1 – KPMG-Gutti Wireless Charging Efficiency Index 

18 

 
Study on wireless charging technologies 

Source: KPMG. 

While  wireless  charging  technology  continues  to  progress,  the  lack  of  a  holistic, 
universally applicable solution, combined with existing technological, economical, and 
consumer-awareness hurdles, presents a landscape of  different solutions which still 
need further development to meet its potential. Industry stakeholders seem to intensify 
efforts in innovation and user convenience. Qi's prevailing status in the mobile phone 
market  could  potentially  extend  with  new  Qi2  products  entering  the  market. 
However, intentions to reach higher power levels and enriched customer experience 
are seen even on the mobile phone market where Qi standard is widely adopted and 
compatible  across  all  devices.  Despite  compatibility  with  Qi,  manufacturers  develop 
different  proprietary  solutions  to  approach  user  expectations.  Additionally,  a 
notable  discrepancy  emerged  as  proprietary  solutions  surpassed  the  widely 
adopted  Qi  standard  in  all  examined  factors  (KPMG-Gutti  Index,  charging  power 
level,  difference  compared  to  wired  charging  time  of  the  respective  phone,  energy 
efficiency, etc.) in the experiment conducted. It's crucial to note that energy efficiency, 
interoperability, compatibility and charging speed remain paramount for broader 
adoption.  

In conclusion, these aspects should be considered regarding possible standardisation 
deliberations for the wireless charging market where experts unanimously agree that 
the technological and market development is still ongoing and is considered to be at 
its early stage. Therefore, currently identification of a potential harmonised charging 
solution is facing challenges, as such common technology has not been found that has 
potential  considering  the  aspects  examined  (such  as  degree  of  market  acceptance, 
charging  performance  and  energy  efficiency).  Decisions  regarding  the  direction  of 
potential  standardisation,  whether  prioritising  energy  efficiency  or  rapid  charging  or 
other aspects, will shape the future landscape of wireless charging technologies. As a 
result,  further  assessment  of  a  potential  harmonisation’s  impact  on  the  wireless 
charging market might be necessary on mid-term. 

The information and views set out in this Study are those of the author(s) and do not 
necessarily  reflect  the  official  opinion  of  the  European  Commission.  The  European 
Commission  does  not  guarantee  the  accuracy  of  the  data  included  in  this  Study. 
Neither  the  European  Commission  nor  any  person  acting  on  the  European 
Commission's behalf may be held responsible for the use which may be made of the 
information contained therein. 

19 

Study on wireless charging technologies 

Résumé analytique 

La présente étude (l'étude) vise à examiner l'état actuel des technologies de recharge 
sans fil pour les téléphones mobiles et les appareils électroniques portables similaires 
par  rapport  à  l'état  décrit  par  l'étude  précédente  de  2021,  en  se  basant  sur  les 
hypothèses suivantes : 

La prédominance de la norme Qi sur le marché de la téléphonie 

• 
mobile est restée inchangée, voire s'est accrue.  

D'autres  approches  et  technologies,  comme  la  recharge  par 
• 
radiofréquence,  ne  sont  toujours  pas  présentes  sur  le  marché  de  la 
consommation, ce qui entache la prédominance de la norme Qi.  

• 
En  ce  qui  concerne  les  normes,  il  n'y  a  pas  de  concurrence 
remarquable sur le marché, ni de concurrent émergent de la norme Qi pour le 
marché des téléphones portables.  

L'industrie est en constante évolution, notamment en ce qui concerne 
les  problèmes 

la  vitesse  de  chargement, 

• 
les  niveaux  de  puissance, 
d'alignement et l'efficacité énergétique.  

• 
Les limites technologiques telles que celles relatives aux facteurs 
de forme n'ont pas encore été résolues, ce qui entraîne une fragmentation 
organique du marché pour différents types d'appareils. 

L'étude vise à analyser l'état actuel du marché de la recharge sans fil et son évolution, 
en  mettant  l'accent  sur  les  futures  solutions  de  recharge  harmonisées  pouvant 
potentiellement  être  intégrées  à  un  cadre  réglementaire.  Différentes  méthodes  de 
recherche ont été combinées pour fournir une vue d'ensemble cohérente du marché 
des  chargeurs  sans  fil  et  pour  alimenter  une  potentielle  réglementation.  Dans  un 
premier temps, une étude documentaire complète a été menée pour comprendre le 
paysage du marché de la recharge sans fil. Cette phase visait à identifier les derniers 
développements et changements technologiques par rapport aux études précédentes. 
Ensuite, une base de données détaillée des produits a été créée, recueillant des 
informations  techniques  sur  les  technologies  de  recharge  sans  fil  pour  différents 
produits. Cette base de données a constitué une ressource cruciale pour l'analyse de 
l'évolution  du  marché  et  des  spécifications  des  produits.  En  outre,  des  entretiens 
structurés  avec  des  experts  ont  été  menés  avec  des  acteurs  du  secteur  afin  de 
recueillir des informations sur l'évolution du marché, les avancées technologiques et 
les expériences des clients, et d'explorer divers aspects, notamment la vue d'ensemble 
du marché, le paysage, les technologies, les perspectives des clients et les possibilités 
de normalisation. À partir des données recueillies auprès des différentes sources, une 
analyse  approfondie  du  marché  a  été  réalisée,  axée  sur  l'identification  des 
tendances, des parts de marché, des taux de pénétration et de la fragmentation du 
marché de la recharge sans fil. 

20 

Study on wireless charging technologies 

En  outre,  une  attention  particulière  a  été  accordée  à  l'efficacité  énergétique,  aux 
performances de charge et à l'interopérabilité des solutions de charge sans fil dans 
le  cadre  de  la  présente  étude.  Avant  de  combiner  les  conclusions  de  l'analyse 
documentaire et les avis des experts, une expérience de mesure a été menée avec 
divers chargeurs sans fil et appareils capables de se recharger sans fil afin d'obtenir 
une compréhension complète de ces aspects. L'analyse du marché ayant révélé qu'en 
matière  d'électronique  grand  public,  aucune  autre  technologie  n'est  largement 
appliquée sur le marché grand public que le chargement par induction, il s'agit de la 
seule  technologie  pouvant  être  évaluée  efficacement  du  point  de  vue  de  l'efficacité 
énergétique et de l'interopérabilité. En ce qui concerne les autres technologies, seules 
de rares sources de haut niveau, ont pu être trouvées qui détaillent ces sujets pour 
l'électronique grand public, et il n'y avait pas de produits disponibles sur le marché qui 
auraient pu être testés pour obtenir des conclusions empiriques. 

L'émergence  des  technologies  de  recharge  sans  fil  pourrait  promettre  une  ère  de 
commodité et de simplicité esthétique pour la recharge des appareils électroniques, 
tout en réduisant l’écart entre l’efficacité énergétique de la recharge sans fil et filaire. 
Toutefois, les conclusions de la présente étude montrent que le paysage actuel est 
caractérisé  par  des  développements  en  cours,  car  les  solutions  actuelles  ne 
répondent pas encore totalement ou même partiellement aux besoins et au confort des 
clients.  Des  efforts  d'innovation  supplémentaires  sont  donc  nécessaires  non 
seulement  pour  améliorer  l'expérience  de  l'utilisateur,  mais  aussi  pour  maximiser 
l'efficacité énergétique des systèmes de recharge sans fil.  

Le marché de la recharge sans fil, évalué à 17,5 milliards de dollars des États-Unis en 
2021, connaît une trajectoire de croissance notable de 25,7 % en glissement annuel 
(Taux de croissance annuel composé, TCAC). Les projections indiquent qu'il atteindra 
185,9 milliards  de  dollars  des  États-Unis  d'ici  2030.  Cette  croissance  est 
principalement  due  à  la  catégorie  des  appareils  électroniques  grand  public,  le 
marché total des smartphones (y compris les appareils non capables de TESF) étant 
de loin le plus important, atteignant 467,6 milliards de dollars des États-Unis en 2024. 
Il  convient  toutefois  de  noter  que  seuls  13 %  des  modèles  de  smartphones  sont 
actuellement  dotés  d'une  fonction  de  recharge  sans  fil,  ce  qui  laisse  entrevoir  une 
marge de progression importante. En outre, du côté des émetteurs, le  secteur des 
émetteurs sans fil grand public est évalué à environ 3,8 à 4,5 milliards de dollars 
des  États-Unis  en  2024,  avec  un  TCAC  attendu  de  3,6 %  d’ici  2030.  Le  marché 
mondial des chargeurs sans fil pour voitures connaît une croissance régulière, avec 
un TCAC prévu de 4,72 % entre 2020 et 2027, ce qui favorise l'adoption de solutions 
embarquées. En 2022, le marché était évalué à environ 1,93 milliard de dollars des 
États-Unis et devrait atteindre 2,55 milliards de dollars des États-Unis d'ici 2030. 

Néanmoins, le paysage technologique est très fragmenté. Il n'existe pas de solution 
universelle qui s'adresse uniformément à tous les appareils, et les spécialistes du 
domaine  sont  sceptiques  quant  à  l'émergence  d'une  telle  solution  dans  l'état  actuel 
des choses. Jusqu'à présent, cette situation a favorisé une segmentation naturelle 
du marché basée sur les attributs physiques des appareils. 

21 

Study on wireless charging technologies 

Les conclusions de la base de données de produits collectés montrent que la norme 
Qi, une forme de charge par induction,  est devenue prédominante dans la sous-
catégorie des téléphones mobiles, ce qui a abouti à une norme de facto grâce à son 
adoption organique par l'industrie. L'évolution et le regroupement de diverses normes 
inductives  dans  des  versions  plus  récentes  de  la  norme  Qi  témoignent  des  efforts 
déployés  pour  améliorer  l'efficacité  et  le  confort  d'utilisation  grâce  à  des 
caractéristiques telles que l'alignement magnétique. Toutefois, le facteur de forme de 
la norme Qi limite son applicabilité à d'autres catégories d'appareils, ce qui défavorise 
actuellement  son  utilisation  dans  les  montres  connectées  et  les  autres  appareils 
électroniques  grand  public  hormis  les  téléphones  mobiles,  pour  lesquels  le 
chargement  sans  fil  n'occupe  pas  encore  une  place  prépondérante.  Le  test  de 
compatibilité  de  l'expérience  a  également  montré  un  niveau  élevé  d'interopérabilité 
entre les smartphones grâce aux solutions Qi (et Qi + propriétaire). En revanche, une 
interopérabilité  moindre  a  pu  être  observée  parmi  les  montres  connectées  testées, 
même dans le cas de produits certifiés Qi, potentiellement en raison de leur forme. 

Pour les autres catégories de produits, la domination de la norme Qi ne se reflète 
pas,  comme  l'indiquent  les  très  faibles  taux  d'adoption.  Bien  que  de  nouvelles 
applications  apparaissent  pour  des  catégories  de  produits  telles  que  les  jouets 
intelligents,  les  meubles  et  autres,  ces  catégories  de  produits  électroniques  grand 
public n'ont pas encore pleinement adopté la recharge sans fil et utilisent souvent des 
solutions  propriétaires,  en  partie  à  cause  de  conceptions  personnalisées  et  d'un 
manque  d'avantages  clairs  pour  le  consommateur  qui  stimuleraient  la  demande  du 
marché. Les conclusions suggèrent également que la recharge sans fil avec la norme 
Qi est principalement mise en œuvre pour les smartphones en raison de leur forme et 
de  leur  taille  adaptées,  alors  que  l'adoption  pour  les  appareils  électroniques  grand 
public de taille plus petite ou plus grande n'a pas été résolue à ce jour d'une manière 
techniquement et économiquement réalisable. 

D'après les conclusions de l'expérience, le chargement par câble continue à dominer 
les solutions sans fil pour tous les paramètres, tels que le temps de chargement, la 
puissance de chargement et l'efficacité énergétique. Ces observations de l'expérience 
pourraient  confirmer  les  conclusions  de  l'analyse  documentaire,  à  savoir  les  limites 
des solutions de recharge sans fil et les raisons de l'adoption relativement plus lente 
des technologies sans fil. 

Malgré sa commodité, la recharge sans fil se heurte encore à des obstacles importants 
qui  doivent  être  surmontés  grâce  à  une  innovation  continue  et  à  l'éducation  des 
consommateurs.  L'efficacité  énergétique  réduite  et 
la  moindre  durabilité 
environnementale  qui  en  résulte,  les  faibles  niveaux  d'interopérabilité  et  de 
vitesse de chargement, ainsi que les problèmes d'alignement accrus continuent 
d'influer sur le potentiel commercial de la technologie. La promesse d'une recharge 
véritablement  sans  fil  pourrait  être  perçue  comme  non  tenue  par  les  clients  qui 
recherchent une plus grande liberté spatiale, actuellement limitée par des exigences 
strictes en matière de couplage et d'alignement. En outre, alors que les systèmes de 
recharge  par  induction  sont  de  plus  en  plus  disponibles,  en  particulier  dans  les 

22 

Study on wireless charging technologies 

secteurs  de  l'automobile  et  de  l'électronique  grand  public,  d'autres  technologies 
comme 
la  recharge  par  radiofréquence  en  sont  encore  au  stade  du 
développement et n'ont pas encore pénétré le marché grand public. 

La  différence  d'efficacité  énergétique  entre  la  recharge  avec  ou  sans  fil  provient  du 
transfert  d'énergie  entre  l'émetteur  et  le  récepteur.  Dans  le  cas  de  la  recharge  par 
induction,  la  perte  d'énergie  dépend  de  plusieurs  facteurs  du  système  de  recharge 
sans fil, tels que l'alignement, la distance, la forme et la résistance des bobines ou la 
fréquence  utilisée.  Les  facteurs  s'influençant  mutuellement,  l'efficacité  ne  peut  être 
déterminée que pour le système de charge complet comprenant le SAE, les câbles, 
l'émetteur,  le  récepteur  et  l'appareil.  Néanmoins,  les  sources  citées  dans  l'analyse 
documentaire  s'accordent  à  dire  que  le  niveau  d'efficacité  énergétique  de  la 
recharge par induction se situe dans une fourchette de 50 à 80 %. En outre, une 
perte d'énergie supplémentaire par rapport aux chargeurs câblés pourrait se produire 
en  raison  de  la  perte  en  mode  veille  et  de  la  production  de  chaleur,  ce  qui  doit 
également être pris en considération lors des analyses du potentiel de normalisation.  

L’expérience menée a confirmé les conclusions de l'étude, tout en indiquant des 
interrelations intéressantes entre divers chargeurs sans fil et appareils. Les scénarios 
de marque à marque ont été les plus performants pour tous les aspects étudiés 
(puissance de charge, temps de charge, efficacité énergétique). Malgré la compatibilité 
des smartphones et des émetteurs, les clients ont pu constater des écarts notables 
dans  les  performances  des  produits  (p.  ex.,  une  différence  de  deux  heures  dans  le 
temps  de  charge).  En  outre,  un  mauvais  alignement  entraîne  une  baisse  de  9  à 
23 % de l'efficacité énergétique. Afin de fournir une mesure complète de l'efficacité 
globale  de  la  recharge,  l'étude  a  introduit  l'indice  KPMG-Gutti  d'efficacité  de  la 
recharge sans fil qui évalue et classe les scénarios de recharge sans fil par rapport 
à leurs équivalents câblés.  

La valeur maximale de l'indice KPMG-Gutti (1) signifie que la méthode de recharge 
sans  fil  donnée  est  aussi  efficace  que  son  équivalent  câblé.  Les  scénarios  dans 
lesquels les smartphones sont rechargés par des émetteurs de la même marque sont 
les  plus  performants  d'après  leur  score  d'indice  (de  0,34  à  0,68).  En  outre,  les 
scénarios  sans  alignement  de  marque  ont  un  score  inférieur  d'environ  50 %  en 
moyenne, ce qui indique des différences entre les scénarios et l'impact substantiel de 
l'alignement de marque sur les performances de charge globales. 

23 

Study on wireless charging technologies 

Figure 2 – Indice d'efficacité de la recharge sans fil KPMG-Gutti 

Source : KPMG. 

Alors que la technologie de recharge sans fil continue de progresser, l'absence d'une 
solution  holistique  et  universellement  applicable,  combinée  aux  obstacles 
technologiques,  économiques  et  de  sensibilisation  des  consommateurs  existants, 
présente  un  paysage  de  solutions  différentes  qui  doivent  encore  être  développées 
pour atteindre leur potentiel. Les acteurs du secteur semblent intensifier leurs efforts 
en matière d'innovation et de confort d'utilisation. Le statut dominant de la norme Qi 
sur le marché de la téléphonie mobile pourrait potentiellement s'étendre avec l'arrivée 
de  nouveaux  produits Qi2  sur  le  marché.  Cependant,  la  volonté  d'atteindre  des 
niveaux  de  puissance  plus  élevés  et  d'enrichir  l'expérience  du  client  est  observée 
même sur le marché de la téléphonie mobile où la norme Qi est largement adoptée et 
compatible  avec  tous  les  appareils.  Malgré  la  compatibilité  avec  la  norme  Qi,  les 
fabricants  développent  différentes  solutions  propriétaires  pour  répondre  aux 
attentes  des  utilisateurs.  En  outre,  un  écart  notable  est  apparu,  les  solutions 
propriétaires  surpassant  la  norme  Qi  largement  adoptée  dans  tous  les  facteurs 
examinés  lors  de  l'expérience  (indice  KPMG-Gutti,  niveau  de  puissance  de  charge, 
différence  par  rapport  au  temps  de  charge  filaire  du  téléphone  concerné,  efficacité 
l'efficacité  énergétique, 
énergétique,  etc.) 

Il  est  essentiel  de  noter  que 

24 

 
Study on wireless charging technologies 

l'interopérabilité, la compatibilité et la vitesse de chargement restent primordiales 
pour une adoption plus large.  

En conclusion, ces aspects devraient être pris en compte dans le cadre d'éventuelles 
délibérations  sur  la  normalisation  du  marché  de  la  recharge  sans  fil,  où  les  experts 
sont  unanimes  pour  dire  que  le  développement  technologique  et  commercial  est 
toujours  en  cours  et  qu'il  est  considéré  comme  étant  à  un  stade  précoce.  Par 
conséquent,  l'identification  d'une  solution  de  recharge  harmonisée  potentielle  se 
heurte actuellement à des difficultés, car aucune technologie commune qui présente 
un potentiel compte tenu des aspects examinés (tels que le degré d'acceptation du 
marché, la performance de recharge et l'efficacité énergétique) n'a été trouvée. Les 
décisions  concernant  l'orientation  de  la  normalisation  potentielle,  qu'il  s'agisse  de 
donner la priorité à l'efficacité énergétique, à la charge rapide ou à d'autres aspects, 
façonneront le paysage futur des technologies de charge sans fil. Par conséquent, une 
évaluation plus approfondie de l'impact d'une harmonisation potentielle sur le marché 
de la recharge sans fil pourrait s'avérer nécessaire à moyen terme. 

Les informations et les points de vue exposés dans cette étude sont ceux des auteurs 
et ne reflètent pas nécessairement l'opinion officielle de la Commission européenne. 
La Commission européenne ne garantit pas l'exactitude des données incluses dans 
cette étude. Ni la Commission européenne ni aucune personne agissant au nom de la 
Commission  européenne  ne  peut  être  tenue  responsable  de  l'utilisation  qui  pourrait 
être faite des informations contenues dans cette étude. 

25 

Study on wireless charging technologies 

1. 

Introduction 

1.1. 

Context of the study 

In  2014,  the  European  Union  took  a  step  towards  fostering  a  unified  approach  to 
charger  compatibility  for  specific  categories  of  radio  equipment  through  the 
implementation  of  the  Radio  Equipment  Directive  2014/53/EU  (EC,  2014)  (RED). 
This directive recognized the necessity for a common charger solution, acknowledging 
its potential benefits for consumers, end-users, and the overall streamlining of radio 
equipment utilisation. The directive’s scope encompasses all electrical and electronic 
equipment that emit radio waves, readily available in both the European Union and the 
European Economic Area. 

Building on the commitment to charger harmonisation, the RED was amended by the 
Directive  (EU)  2022/2380  (EP,  2022),  which  was  officially  published  in  2022.  This 
directive  represents  a  significant  stride  towards  achieving  a  standardised  charging 
solution,  often  referred  to  as  the  ‘Common  Charger’.  The  primary  focus  of  this 
amendment  revolves  around  the  introduction  of  precise  technical  requirements 
applicable  to  specific  categories  or  classes  of  radio  equipment  capable  of  being 
recharged via wired methods. (For further detail regarding to regulatory background, 
please refer to section 4.1.). 

In preparation to the regulatory efforts outlined above, a technical study on wireless 
charging  technologies  was  commissioned  and  subsequently  published  by  the 
Commission in 2021 (further referred as Predecessor Study). The study aimed to: 

•  Assess the current state of the wireless charging market; 

• 

Identify the main technical aspects of interoperability; 

•  Define a suitable product scope. 

The  Predecessor  Study  showed  that  the  wireless  charging  market  is  still  a  growing 
market with low level of fragmentation. There was no strong indication that wireless 
charging would entirely replace wired charging due to the low energy efficiency of the 
wireless  charging  technologies.  Hence,  it  would  have  been  premature  to  already 
select the most appropriate common technical solution (for instance the Qi solution). 

However, despite the cautious approach, the co-legislators recognised the importance 
of  vigilance  regarding  market  fragmentation.  As  a  result,  the  RED  as  amended  by 
Directive (EU) 2022/2380 empowers the Commission to take proactive measures in 
order to ensure market cohesion. 

Specifically, the amended directive allows the Commission to call upon one or more 
European  standardisation  organisations  to  develop  harmonised  standards  that 
define  the  technical  specifications  for  charging  interfaces  and  communication 

26 

Study on wireless charging technologies 

protocols related to radio equipment that can be recharged through  methods other 
than  traditional  wired  charging.  This  important  provision  is  set  to  be  in  effect  by 
December 28, 2024. 

By incorporating this mechanism into the regulatory framework, the European Union 
demonstrates  its  commitment  to  adapt  to  evolving  technological  landscapes  while 
ensuring that fragmentation in the market is closely monitored. This approach enables 
the EU to respond effectively to emerging trends in the wireless charging sector and 
promote  the  development  of  harmonised  standards  as  needed,  further  enhancing 
consumer convenience, and reducing unnecessary complexity. 

In this context, the Directorate General for Internal Market, Industry, Entrepreneurship 
and SMEs (DG GROW) commissioned KPMG Hungary for external expertise to assist 
with an updated assessment of the status of wireless charging technologies in view of 
assessing the appropriate harmonised charging solution for devices capable of being 
recharged by means of wireless charging. 

1.2. 

Objectives 

The objective of the project is to carry out an updated and extended assessment of 
the status of wireless charging technologies. More specifically, the study focuses on: 

•  The status (technical and economic) of wireless charging technologies; 

•  The possible future technological developments; and 

•  Possibilities  of  a  potential  future  harmonised  charging  solution  (for 

instance interface and charging communication protocol) 

concerning portable consumer electronics with power levels up to 240 W. 

The following subjects are investigated under the framework of the current research: 

•  Energy  efficiency  and  charging  performance 

(which  can  cause 
inconvenience  to  the  consumers)  are  key  elements  in  the  new  study. 
Accessible and relevant information in this field is investigated and included in 
the comparative study. 

•  Update  of  the  comprehensive  analysis  of  market  developments,  market 
shares,  market  penetration,  market  fragmentation,  technological  performance 
and features. Notably, this only refers to subjects where new data is available, 
as there are some aspects where the available market data is not newer than 
2021. 

•  Regarding  technological  features,  the  study  provides  information  on  the 
interface between the device and the charging pad, their interporeability 
and sources powering the technology.  

27 

Study on wireless charging technologies 

•  As important factor, the present study analyses high-level aspects of customer 

acceptance and user convenience as well.  

•  Available  information  and  data  like  legislation  and  previous  studies  are  used 
and  referred  to  the  final  report,  with  special  attention  to  findings  from  the 
evaluation of power supply regulation (DG ENER) 

Our  understanding  is  that  depending  on  the  findings  and  conclusions  of  the 
assessment,  the  Commission  intends  to  issue  a  standardisation  request  to 
European  Standardisation  Organisations  to  draft  harmonised  standards  laying 
down 
interface(s)  and  charging 
communication protocol(s) for radio equipment capable of being recharged by wireless 
charging. 

technical  specifications 

the  charging 

for 

To  this  end,  the  study  includes  an  analysis  related  to  the  market  of  wireless 
charging  technologies  (developments,  shares,  penetration,  and  fragmentation  – 
Task  1)  but  also  the  analysis  of  the  interoperability,  energy  efficiency, 
technological  performance,  interferences  and  charging  performances  of  the 
wireless charging technologies (Task 2). Technologies already standing out compared 
to  others  are  highlighted  and  findings  from  the  activities  conducted  in  Task  1  are 
comprised. . Most efficient solutions are presented in the Final Report based on the 
outcomes of Task 1 and Task 2 (see 1.3.). 

In order to properly justify the findings of the assessment, the analyses and the agreed 
requirements have been supported by interviews with key stakeholders beyond desk 
research and literature review. 

The deliverables provide evidence-based information, sound analysis of findings and 
adequate  resource  for  considerations  on  a  potential  issuing  of  a  standardisation 
request.  

28 

 
 
 
 
 
 
 
Study on wireless charging technologies 

1.3. 

Content of the study 

Following the Tender Specifications and based on the proposed methodology, the final 
study is structured around two main tasks, clustered in four stages: 

1. 

Inception  phase  –  completed  by  delivery  of  the  current  document 
(Inception Report) 

(a)  Activity 1.1: Preparation and conduction of kick-off meeting 

(b)  Activity 1.2: Interview with additional stakeholders relevant during this 
phase identified by DG GROW and KPMG: Cosmin Codrea, who is in 
charge  of  the  review  of  the  EPS  regulation  (DG  ENER)  as  a  Policy 
Officer  

(c)  Activity 1.3: Elaboration of Inception Report (D1) 

2. 

Task  1:  Collection  of  market  data  related  to  wireless  charging 
solutions 

(a)  Activity 2.1: Mapping the market through desk research and literature 

review 

(b)  Activity 2.2: Conduct stakeholder interviews 

(c)  Activity  2.3:  Creation  of  a  product  database  with  detailed  technical 

information on technology used 

(d)  Activity 2.4: Conduction of a detailed market analysis 

(e)  Activity 2.5: Elaboration of Interim Report (D2) 

3. 

Task 2: Analysis of technical requirements and charging types 

(a)  Activity 3.1: Analysis of each technology selected 

(b)  Activity 3.2: Analysis and figures on interoperability 

(c)  Activity 3.3: Analysis and figures on energy efficiency 

4.  Synthesis: 

(a)  Activity 4.1: Comparative assessment of the various wireless charging 

solutions 

(b)  Activity  4.2:  Synthesis  and  preparation  of  Final  Report  (D3)  with  an 
executive summary, an abstract and submission of all data collected 
(D4) 

29 

Study on wireless charging technologies 

2. 

Methodology 

The  core  process  of  the  project  is  the  mapping  of  the  latest  technological 
developments on the wireless charger market and changes compared to the state 
depicted by the Predecessor Study. For this purpose, a comprehensive analysis has 
been conducted, discovering current dynamics both on the demand as well as on the 
supply side of the market. The demand side refers to the acceptance and penetration 
of  existing  technologies  among  customers,  whereas  the  supply  side  encompasses 
technological  developments,  while  also  pointing  out  innovations  and  practical 
knowledge still unexplored by the market. As the overall aim of the study is to provide 
outlooks  concerning  a  potential  future  harmonised  charging  solution  which  may  be 
included  in  legislative  directives,  a  special  emphasis  will  be  given  to  market 
fragmentation and standardisation possibilities. 

Task 1 aimed to collect all information which may be relevant for the goal of the study. 
Therefore,  different  research  tools  were  applied  to  enhance  advantages  of  each 
method  while  mitigating  their  limitations  in  order  to  provide  an  objective  and  broad 
perspective.  To  this  end,  the  assessment  embraces  analytical  desk  research, 
literature review, data acquisition and analysis as well as interviews with main 
stakeholders representing different types of organisations and market players. The 
overall research design uses quantitative as well as qualitative research relying on both 
technical data sources and expert input.  

Task 2 supplemented these findings with an in-depth investigation of energy efficiency 
and interoperability aspects relevant for wireless charging. This part of the research is 
based on literature review focusing on technical specifications and descriptions on 
the  one  hand,  and  an  empirical  experiment  on  the  other  hand.  The  experimental 
design is detailed in section 6.2. 

2.1. 

Desk research and literature review 

As  basic  concept,  any  research  question  (RQ)  is  approached  by  an  initial  desk 
research,  mapping  relevant  scientific  studies,  latest  trends  as  well  as  secondary 
literature (Table 1). Additionally, taking the legislative aim of the study into account, 
special attention is granted to studying the regulatory context, also considering the 
ongoing  revision  of  the  Commission  Regulation  (EU)  2019/1782  laying  down 
ecodesign  requirements  for  external  power  supplies  (EPS)  conducted  by 
DG ENER, using the outcomes of the interview with the EC representative in charge 
of it. Further, the study considers several pieces of literature and documents from this 
perspective,  in  particular  whether  their  conclusions  remain  valid  and  relevant  with 
respect to the common chargers. 

30 

 
Study on wireless charging technologies 

Table 1 – Reviewed literature by type 

Literature type 

Pieces reviewed 

Business whitepapers / reports 

Industry alliance content 

Manufacturer website 

Market research  

Other 

Press releases 

Regulatory document 

Scientific publication 

Study 

Tech reviews 

Technical documentation, specification 

Grand Total 

10 

13 

2 

26 

3 

4 

7 

34 

1 

5 

2 

107 

2.2. 

Product Database 

It  is  also  crucial  to  identify  technological  solutions  and  requirements  which  are 
widely  used  by  (device  and  transmitter)  manufacturers.  Therefore,  besides 
reviewing  latest  literature,  statistics  on  wireless  charging  market  and  technological 
development through desk research, numerous products’ technical documentation 
and information were reviewed on the market in order to create a Product Database 
(PD). In line with the Study’s objective, information on products were collected that are 
either: 

• 

transferring  energy  to  wireless  charging  capable  devices  -  referred  as 
Transmitters within the PD (standalone or embedded); 

•  using  rechargeable  batteries  (removable  or  not)  that  charge  by  means  of 

wireless charging - referred as Devices within the PD; 

•  enabling wireless charging for devices that do not have built-in wireless charging 

capabilities – referred as Add-on receivers within the PD; 

and  could  benefit  from  a  harmonised  wireless  charging  solution.  Laptops  were  not 
included in the research based on the findings of desk research and expert interviews. 
Though  some  wireless  solutions  exist  on  the  market  (such  as  Lenovo’s  Wireless 
Charging  Kit  which  contains  a  specific  Transmitter  and  an  Add-on  receiver1),  the 
currently  available  solutions,  mainly  due  to  their  relatively  low  power  levels,  are  not 
suitable to charge laptops appropriately. Additionally, it was also highlighted in some 
expert interviews that further development is required to charge laptops in a way that 
could be considered as an alternative of wired charging. Nevertheless, development 

1 Lenovo: Lenovo Go USB-C Wireless Charging Kit | Lenovo Angola, downloaded February 16, 2024 

31 

 
Study on wireless charging technologies 

of  a  solution  that  would  be  suitable  for  laptops  is  ongoing  according  to  expert 
interviews. Hence, a future analysis of this category after the release of these solutions 
could uncover further insights.  

During the development of the PD, the following data collection principles have been 
used for all above mentioned categories that ensure to present the current situation on 
the market and to assess the market development and changes since the Predecessor 
Study was issued. These principles were the following: 

•  Products that were released before 2021 are not included in the PD; 

•  Products that could not be purchased in such a form that a customer can use 
them with a suitable transmitter/device without additional assembly are not 
included in the PD (e.g.: receiver chips); 

•  Products that are not yet commercially available on the market until the 1st 
of  January  2024  are  not  included  in  the  PD  as  these  items  could  not  be 
purchased  by  customers.  In  other  words,  products  released  in  2024  are  not 
included in the PD. 

Additionally, data collection for the PD was closed by 31st of January 2024 (last item 
was added on 31st of January 2024). Therefore, it needs to be stated that standards 
released after this date might be missing or underrepresented at the moment of the 
finalisation of the Study since, for instance, Qi2 standard was released in 2023, first 
products were available on the market in December 2023 and hundreds of products 
are currently in the certification process according to interviews. 

Besides general data collection principles, a systematic approach was employed to 
collect a representative subset of items for the two main categories (Transmitters, and 
Devices). The following principles were used for Transmitters2,3: 

•  Multiple  vendors’  product  portfolios  have  been  reviewed  during  data 
collection in order to create a robust product database. These vendors are the 
following: 

o  The 22 biggest wireless charging companies according to Statista data 

series4, 

2 During the review of product portfolios, no difference was made between standalone charging pads 
and charging pads that can be built into furniture by consumers themselves and sold separately as 
accessories 

3  Embedded  wireless  chargers  were  also  collected  through  extensive  desk  research  and  various 
examples  were  identified.  However,  there  is  no  available  information  about  the  number  of 
embedded  wireless  charger  use  cases  on  the  market.  Therefore,  the  gathered  list  could  not  be 
considered fully representative. 

4 Statista: Global wireless charging companies by revenue 2023 | Statista; downloaded December 6, 

2023 

32 

 
Study on wireless charging technologies 

o  The 5 biggest smartphone manufacturers’ (according to Yahoo Finance) 

own wireless chargers5,  

o  Other  brands  indicated  in  Statista  data  series  and  found  during  desk 

research. 

The following approach was used for Devices: 

•  Primary  focus  on  product  types  defined  in  Directive  (EU  2022/2380)  while 
wireless  charging  capable  device  categories  identified  in  the  Predecessor 
Study’s product database were also reviewed. 

•  Among device categories, special attention was given to smartphones as this 
device  category  is  the  most  important  one  based  on  expert  interviews  as  it 
drives wireless charging market, being the most popular product classes among 
consumer  electronics6.  Therefore,  data  regarding  the  20  biggest  smartphone 
manufacturers’7 devices were collected. 

•  Other device categories were collected by considering the following aspects: 

o  Popularity of device category; 

o  Proportion of device category in the consumer electronics market (by 

volume / by value); 

o 

Inputs received from expert interviews; 

o  Available use cases for wireless charging capability. 

It must be highlighted that information was not available on the proportion of wireless 
charging  capable  devices  (by  volume  or  by  value)  among  all  consumer  electronics 
devices  nor  an  absolute  level  nor  category  level.  Additionally,  wireless  charging 
capability could depend on several factors (power level, function, etc.). Hence, no exact 
correlation can be identified for instance between consumer electronics popularity and 
wireless charging capability. Therefore, equal attention was given to other product 
categories during data collection and the difference in number of items per product 
category could occur due to the different order of magnitude in use-cases. 

Regarding  Add-on  receivers,  very  limited  information  was  found  during  the  data 
collection  period,  despite  reviewing  companies’  website  as  well  as  further  relevant 
sites.  Only  four  items  could  be  highlighted  in  the  PD  and  only  one  of  them  had 
information  on  its  release  date.  Moreover,  the  category  was  already  in  decline 

5  Yahoo:  https://finance.yahoo.com/news/20-most-valuable-smartphone-companies-150542982.html, 

downloaded January 31, 2024 

6 Oberlo: Most Popular Electronics Worldwide [Updated Dec 2023] (oberlo.com); downloaded January 

31, 2024 

7  Yahoo:  https://finance.yahoo.com/news/20-most-valuable-smartphone-companies-150542982.html, 

downloaded January 31, 2024 

33 

 
Study on wireless charging technologies 

according  to  the  Predecessor  Study  due  to  the  expansion  of  wireless  charging 
capability being directly embedded into devices by manufacturers, which was in line 
with the result of desk research and insights from expert interviews. Therefore, a limited 
number, precisely four items have been recorded in the PD. 

The PD is intended to follow the structure prescribed in the Predecessor Study to allow 
comparison and support the analysis of market developments. Therefore, information 
from the products were collected from different sources and is summarised in Table 
2. Nonetheless, despite there were some cases where product data points were not 
described  in  publicly  available  documents  (for  instance  input  power  level  of 
smartwatches  and  earbuds  or  the  input  voltage  and  amper  level  of  transmitters), 
sufficient amount of information was found to fulfil the Study’s objectives. 

Table 2 – Product Database data structure 

Transmitters 

Add-on receivers 

Devices 

•  Brand 

•  Product name 

•  Product type 

•  Embedded type 

•  Year of release 

•  Brand 

•  Product name 

•  Product type 

•  Year of release 

•  Brand 

•  Product name 

•  Product type 

•  Year of release 

•  Supported technology 

•  Supported technology 

•  Supported technology 

•  Potential power level 

•  Potential power level 

•  Number of wireless 
chargers stands 

•  Potential power level 

•  Voltage 

•  Amper 

•  Connector type 

•  Source 

Source: KPMG, 2024 

•  Voltage 

•  Amper 

•  Connector type 

•  Source 

• 

Length (mm) 

•  Width (mm) 

•  Height (mm) 

•  Weight (g) 

•  Cable type 

•  Source 

This combined approach led to the identification of 380 products from 82 brands that 
could  be  used  as  a  reference  to  assess  the  current  market  and  also  the  changes 
compared to the Predecessor Study’s findings. Proportions of different product types 
are  highlighted  in  Table  3  below.  However,  it  must  be  noted  that  the  PD  does  not 
include all Transmitters, Add-on receivers and Devices available on the market. 

34 

 
 
 
Study on wireless charging technologies 

Table 3 – Product database summary 

Device 

Number of analysed products 

Standalone transmitters 

Embedded transmitters 

Add-on receivers 

Smart phone 

Smart watch 

Earbuds 

Headsets (incl. headphones)8 

Mice 

Tablet 

Toothbrush 

Digital camera 

Keyboard 

Shaver 

Smart pen 

e-reader 

Source: Product Database 

105 

34 

4 

141 

47 

30 

3 

4 

3 

2 

1 

1 

1 

1 

1 

2.3. 

Stakeholder interviews 

Whereas the mentioned data is expected to adequately reflect the current state of the 
wireless charging market, they give very few information about backgrounds and future 
developments.  Therefore,  interviews  were  conducted  with  experts  and  main 
stakeholders to detect reasons behind actual developments and expected directions 
of future growth. Stakeholders were consulted for better assessment of current 
dynamics  on  the  market  and  technologies  applied  by  producers.  In  order  to  get  a 
complete  picture  of  the  market,  a  reasonable  amount  of  interviews  were  conducted 
embracing several stakeholder groups from different sectors. Table 4 summarises 
the conducted interviews. 

Table 4 – List of conducted interviews 

Date 

Organisation 

18.12.2023  DG ENER 

05.01.2024  AirFuel Alliance 

08.01.2024  UL Solutions 

8 The term "headset" as used herein refers to devices designed to be worn on the head, irrespective of 

the presence or absence of a microphone 

35 

 
Study on wireless charging technologies 

Date 

Organisation 

09.01.2024  NFC Forum 

09.01.2024  Qualcomm 

10.01.2024  Deutsche Telekom  

11.01.2024  DigitalEurope 

15.01.2024  Hama  

16.01.2024  OPPO 

17.01.2024  WPC/Philips 

23.01.2024  WPC 

23.01.2024  Powercast 

25.01.2024  Aeterlink 

26.01.2024  NXP 

26.01.2024  Ossia 

30.01.2024  Samsung 

01.02.2024  Energysquare 

06.02.2024  Sony 

09.02.2024 

LEGO 

12.02.2024 

European Association for Coordinating Consumer Representation in 
Standardisation (ANEC) 

15.02.2024  Apple 

08.03.2024 

Logitech 

18.03.2024  University of Auckland 

Written  Huawei 

Written 

ZTE 

36 

Study on wireless charging technologies 

During the selection of interviewees, the principles below have been followed: 

•  Cover  organisations  that  developed  or  promote  a  wireless  technology 

standard; 

•  Cover  main  industry  players  (mainly  device  and  charger  manufacturers, 

businesses); 

•  Allow  comparison  with  the  Predecessor  Study  (cover  10  out  of  the  14 

stakeholders that were interviewed during the Predecessor Study); 

•  Cover stakeholder segments requested in the Tender Specification. 

Interviews  were  semi-structured  using  the  question  pool  which  was  approved  by 
European  Commission  based  on  the  Inception  Report  (D1).  The  indicative  guide  is 
attached under Annex I. The actual questionnaires have been tailored depending on 
the interviewee, e.g. regarding the role of the relevant organisation in the industry. 

47  organisations  have  been  approached,  out  of  which  25  interviews  have  been 
conducted. The rate of non-responsiveness was 43%.  

Table 5 – Full summary of contacted organisations 

Organisation name 

Cluster 

Responsiveness 

Aalto University 

Aeterlink 

Aira Power  

AirFuel Alliance 

Anker  

Apple 

Others 

Non-responsive 

Charger manufacturer 

Interviewed 

Charger manufacturer 

Non-responsive 

Industry associations 

Interviewed 

Charger manufacturer 

Non-responsive 

Device &charger manufacturer 

Interviewed 

Battery University 

Others 

Non-responsive 

Belkin  

Bitkom 

Bravo Group 

Deutsche Telekom  

DG ENER 

DigitalEurope 

Eggtronic 

Energous 

Energysquare 

European Association for Coordinating 
Consumer Representation in Standardisation 
(ANEC) 

Charger manufacturer 

Non-responsive 

Industry associations 

Non-responsive 

Others 

Others 

Regulatory body 

Industry associations 

Charger manufacturer 

Charger manufacturer 

Declined 

Interviewed 

Interviewed 

Interviewed 

Non-responsive 

Non-responsive 

Charger manufacturer 

Interviewed 

Consumer associations 

Interviewed 

37 

 
Study on wireless charging technologies 

Organisation name 

Cluster 

Responsiveness 

FAST CR  

Granite River Labs 

Hama  

Huawei 

LEGO 

LG 

Logitech 

MiPow 

Mophie (by ZAGG) 

NFC Forum 

Nokia 

NXP 

OPPO 

Ossia 

PopSockets 

Powercast 

PowerSphyr 

Qualcomm 

REUSE - Re-use and recycling European 
Union social enterprises 

Consumer associations 

Test Labs 

Others 

Non-responsive 

Non-responsive 

Interviewed 

Device &charger manufacturer 

Written interview 

Others 

Device manufacturer 

Device manufacturer 

Charger manufacturer 

Charger manufacturer 

Interviewed 

Declined 

Interviewed 

Non-responsive 

Non-responsive 

Industry associations 

Interviewed 

Device manufacturer 

Non-responsive 

Others 

Interviewed 

Device &charger manufacturer 

Interviewed 

Charger manufacturer 

Interviewed 

Charger manufacturer 

Non-responsive 

Charger manufacturer 

Interviewed 

Charger manufacturer 

Non-responsive 

Charger manufacturer 

Interviewed 

Consumer associations 

Non-responsive 

RVO Netherlands  

Others 

Non-responsive 

Samsung 

Sony 

UL Solutions 

University of Auckland 

Vodafone 

Wi-Charge 

WPC 

Xiaomi 

Device manufacturer 

Device manufacturer 

Test labs 

Others 

Others 

Charger manufacturer 

Interviewed 

Interviewed 

Interviewed 

Interviewed 

Non-responsive 

Non-responsive 

Industry associations 

Interviewed 

Device &charger manufacturer 

Declined 

Yole Developpement 

Market research 

Non-responsive 

ZTE 

Source: KPMG, 2024 

Device &charger manufacturer 

Written interview 

2.4. 

Market analysis 

With the outputs of the previous activities, an appropriate amount of information has 
been collected and structured to perform a market analysis for radio equipment with 
power  levels  up  to  240  W  using  rechargeable  batteries  (removable  or  not)  that 

38 

 
 
Study on wireless charging technologies 

charge by means of wireless charging and could benefit from a harmonised wireless 
charging solution. The aim of this market analysis was to 

•  Understand the market developments, market shares, market penetration 
and market fragmentation concerning wireless charging developments on the 
wireless charging market; 

• 

Identify  any  significant  changes  in  the  technological  capabilities  of  wireless 
chargers; 

•  Uncover whether the conclusions in the Predecessor Study remained valid. 

The analysis also includes a comparison of the database to the status depicted in the 
Predecessor Study, as it provides excellent insights to developments and changes of 
the market. 

•  Creating figures based on charging technologies used by transmitter and 
device producers. Leveraging data from the well-structured product database, 
it  is  also  assessed  what  type  of  technologies  are  primarily  used  by 
manufacturers. The figures also intend to compare the used type of interface, 
communication protocol, interoperability by transmitter and device producers. 

•  Update and analysis of main sales figures and volumes from Predecessor 
Study. A majority of the figures on quantitative market data has been collected 
from Statista in the Predecessor Study. The same sources are used primarily to 
be  able  to  perform  a  comparison  and  highlight  recent  market  developments 
together  with  other  changes  in  figures  on  market  shares  and  other  relevant 
metrics. Nevertheless, multiple sources have been checked for available new 
data  in  order  to  create  an  update  of  the  analysis  of  main  sales  figures  and 
volumes. Changes compared to the state of 2021 are validated through a review 
of the economic and technological context.  

•  Analysis  of  changes  in  available  technologies  and  standards  on  the 
market. By comparing the findings of the Predecessor Study and the results of 
the previous activities of Task 1, technological developments can be identified 
from transmitter and device producers’ side. The analysis covers among others 
the  type  of  wireless  charging  technology,  interface,  communication  protocol, 
and the type of interoperability. This also indicates if there is still a predominant 
standard  on  the  market  or  whether  a  greater  competition  between  standards 
can be identified. 

•  Further complementary market analysis with focus on single categories 
of consumer electronics based on the reviewed literature, desk research 
and stakeholder interviews. As the market is rapidly changing, further analysis 
was required based on the findings of previous activities. As a result, the list of 
analyses was finetuned in an iterative manner. 

39 

Study on wireless charging technologies 

The main findings and outputs of the activities included in Task 1 (for instance, product 
database and figures on market trends) are all integrated into the present Study in a 
well-structured format.  

2.5. 

Voice of the Customer 

Recognising the importance of understanding consumer experiences and perceptions, 
the  Study  adopted  a  systematic  approach  to  gather  and  analyse  customer 
feedback.  This  approach  involved  collecting  customer  reviews  and  conducting 
qualitative content analysis to uncover insights into prevalent pain points and barriers 
faced  by  users.  The  integration  of  real  customer  insights  with  literature  review 
findings and expert insights provided validation and underscored the significance of 
merging real-world experiences with theoretical knowledge. 

• 

Identification of wireless charging transmitters. A systematic approach was 
employed to identify wireless charging transmitters. By taking the items of the 
Product  Database  (PD)  as  well  as  the  best-selling  items  on  Amazon  into 
consideration,  ensuring  a  wide  array  of  transmitters  for  subsequent  analysis. 
Amazon  was  chosen  due  to  its  global  recognition  as  a  major  e-commerce 
platform, offering a diverse selection of products and verified customer reviews. 
This facilitated access to detailed information about each product, with a total of 
70 different products from 42 brands included in the analysis.  

•  Collection of real customer reviews. Customer reviews were collected from 
Amazon, prioritising those provided by verified buyers. Emphasis was placed 
on 1-star reviews to capture critical perspectives, as they often highlight genuine 
issues faced by consumers. A total of 820 unique evaluations were examined 
to ensure a comprehensive spectrum of feedback. 

•  Qualitative  content  analysis.  Qualitative  content  analysis  techniques  were 
applied  to  the  collected  customer  reviews.  This  involved  a  systematic 
examination  of  textual  content  to  identify  recurring  themes,  sentiments,  and 
patterns related to user experiences with wireless charging technology. 

•  Visualisation.  Wordcloud  visualisation  was  generated  to  represent  the 
frequency of keywords and phrases extracted from the customer reviews. This 
graphical representation allowed for a quick and intuitive understanding of the 
transmitters, 
most  commonly  mentioned  aspects  of  wireless  charging 
highlighting key themes and sentiments expressed by users. 

•  Grouping  main  pain  points.  Through  qualitative  content  analysis,  the  main 
pain  points  expressed  by  consumers  in  their  reviews  were  identified  and 
categorised.  These  encompassed  usability  issues,  compatibility  concerns, 
reliability challenges, and user satisfaction levels. 

•  Comparison  with  hypotheses.  The  findings  from  the  qualitative  content 
analysis were compared with hypotheses derived from the literature review and 

40 

Study on wireless charging technologies 

expert interviews. This step involved evaluating the extent to which the identified 
pain  points  and  insights  from  real  customer  reviews  aligned  with  or  deviated 
from the expectations outlined in existing research and expert opinions. 

41 

Study on wireless charging technologies 

3. 

Technical overview 

3.1. 

Typology and definition of wireless charging solutions 

Brief introduction into the technology 

Wireless charging or as widely referenced, wireless power transfer (WPT) describes 
the process of transmitting electricity from a power source to charge up the receiving 
device  without  the  use  of  cables  or  any  physical  electrical  connection  between  the 
device  and  the  transmitter  (e.g.  magnetic  connector).  Its  long-term  prospects  in 
consumer electronics are: reduced need for cable production due to longer lifespans 
of  cables,  reducable  battery  sizes  or  even  elimination  of  batteries  in  some  cases 
(Nnamdi & Asianuba, 2023)9.  

Different technologies have emerged in this field, with inductive coupling, magnetic 
resonant  and  radio  frequency  (RF)  technologies  as  the  most  widespread  types 
among  others.  A  detailed  description  of  wireless  charging  and  technologies  can  be 
found under chapter 3.2.2. 

To ensure safety, interoperability and efficiency, standards have been developed for 
different  technologies.  Products  labelled  with  any  standard  certification  have  to 
undergo a rigorous testing procedure to ensure compliance with recommendations 
of  the  standard  associations,  which  embrace  several  industry  stakeholders  and 
manufacturers. The main identified standard associations for wireless charging are the 
Wireless Power Consortium (WPC) , the AirFuel Alliance and the NFC Forum. The 
aim of the present study is to assess the technological and economic developments 
on  the  wireless  charging  market  to  identify  current  fragmentation  factors  and  the 
maturity of the market enabling standardisation.  

Current use cases 

According to the interviews and findings from the Product database, current use cases 
embrace mostly smartphones and small consumer electronics like smartwatches and 
earbuds, with inductive charging as the most widespread technology, often using the 
Qi standard or a proprietary technology (see chapter 5). These findings are in line with 

9 The idea of eliminating batteries does not mean that devices will not need to be charged anymore. 
Instead,  it  suggests  a  future  in  which  devices  may  continuously  be  powered  via  wireless  power 
transfer  (WPT),  reducing  or  potentially  eliminating  the  reliance  on  traditional  removable  or 
replaceable batteries. Devices would be designed to receive energy wirelessly in real-time from a 
nearby power supply and would still require energy; they would just receive it wirelessly rather than 
depending on stored energy in a battery (Nnamdi & Asianuba, 2023). There is still a long way to go 
in terms of technological development, infrastructure, regulation, and consumer adaptation before 
this vision becomes realisable. 

42 

 
Study on wireless charging technologies 

the Predecessor Study, no major shifts could be observed away from Qi’s dominance. 
However,  other  means  of  wireless  charging  for  consumer  electronics  seem  to  be 
existing,  but  rarely  observable  in  actual  consumer  products.  Existing  standards  and 
their features are detailed under chapter 3.2.3. 

Changing use cases – mid-term perspectives 

The landscape of wireless charging technology is undergoing a transformative shift 
as it  finds new  and  diverse  applications.  Based on interviews,  these include among 
others the healthcare sector, (consistently powered medical devices and wearables, 
ready for immediate use), the industrial sector, the automotive sector (charging electric 
vehicles  wirelessly)  and  also  some  kitchen  appliances  (WPC,  2024d)10.  Market 
information regarding these product categories can be found in chapter 4.2.2., but as 
this Study is focusing on consumer electronics below 240 W, neither of the above 
mentioned examples will be discussed in detail.  

Another use case with promising potential which has been identified during stakeholder 
interviews  is  in-car  wireless  charging,  using  the  car’s  battery  as  power  supply  for 
charging consumer electronics, mainly phones, and therefore considered as relevant 
for the present Study. 

Further, interviews revealed that the spread of wireless charging technology continues 
through different sectors, with some less obvious examples like toy manufacturing. 
Smart, or battery-charged toys’ usability can be enhanced by eliminating the need of 
wires.  Due  to  shape  and  size  considerations,  examples  seen  during  the  Study  use 
other methods than inductive charging. These innovations in the toy industry show that 
wireless  charging  has  further  development  potential  beside  from  inductive 
technology, enabling new use cases. 

Emerging new use cases – long-term prospects 

This  may  also  inspire further innovation,  as  new  use cases for wireless charging 
technology  are  reshaping  the  way  consumers  interact  with  various  aspects  of  the 
connected world, according to the vision of some interviewees. One observable trend 
is the integration of wireless charging with the Internet of Things (IoT). As IoT devices 
continue to proliferate in people’s daily lives, wireless charging plays a crucial role in 
powering these interconnected gadgets. Whether it's smart home devices or industrial 
sensors, the ability to charge IoT devices without wires or even manual intervention 
enhances  the  economic  efficiency  and  reliability  of  these  interconnected  systems. 

10 Technology for wirelessly charged kitchen appliances is currently under development by the WPC 
with the Ki Cordless Kitchen Standard utilizing inductive charging. Similar looking solutions using 
conductive  charging  by  direct  connection  to  a  charging  surface  through  pines  are  sometimes 
marketed as wireless charging, while technically being disconnectable wired charging. The current 
section therefore does not refer to such appliances. 

43 

 
Study on wireless charging technologies 

Though  it  has  to  be  noted  that  such  an  automated,  ubiquitous  manner  of  charging 
requires capability of reaching larger distances of at least a few meters, similar to WiFi 
technology. Considering the range aspect, this scenario would be most likely for RF 
charging methods, which need further development to overcome health issues and 
currently  are  viable  for  charging  only  low-power  devices,  as  highlighted  in  many 
interviews conducted for the Study. Further, most efficient usage of RF charging can 
be reached through setting up a charging system simultaneously and steadily powering 
multiple  devices,  which  could  imply  new  use  cases  in  building  planning  and  energy 
management. Therefore, given that adoption by both end users and industrial players 
is crucial,  this scenario  is unlikely  to  be implementable  on the  short  term, but  could 
provide promising outlooks for the future. 

Another interesting opportunity is the integration of wireless charging infrastructure in 
smart  cities.  In  this  scenario  depicted  in  some  interviews,  devices  are  constantly 
charging, creating a seamless and continuous power supply for various applications in 
urban  environments,  such  as  electric  vehicles,  streetlights,  and  public 
infrastructure.  This  perspective  may  cover  wireless  charging  solutions  for  electric 
scooters and bicycles, providing an effortless and convenient way for users to keep 
their personal electric vehicles charged. Moreover, incorporating wireless charging into 
public transportation systems, such as buses or trains, could support an exponential 
spread of wireless charging usage. Additionally, the integration of wireless charging 
technology in outdoor recreational spaces, like parks or camping sites, could offer 
users  a  convenient  and  eco-friendly  way  to  power  their  devices  while  enjoying  the 
outdoors.  These  emerging  use  cases  showcase  the  future  potential  for  wireless 
charging to revolutionise various aspects of people’s lives, making technology more 
seamless, efficient, and integrated into their daily routines. 

Typology and definition of wireless charger systems 

The present study operates basically with the definition used in the Predecessor Study, 
extending it with some amendments concerning Transmitter definitions.  

The following elements constitute a charging system: 

•  External Power Supply (EPS)  

•  Cable assembly  

•  Transmitter (standalone or embedded; referred to as “Tx” in research literature) 

•  Receiver (embedded or add-on; referred to as “Rx” in research literature) 

It should be noted that the EPS  is the source providing the transmitter with energy, 
which can happen through  

•  a mains-powered system, that is an electricity supply from connecting to the 

utility grid through a socket (“power from the wall”), 

44 

Study on wireless charging technologies 

•  power  drawn  from  the  battery  of  other  devices  when  connected  through  a 
cable or a USB C port, e.g. cars or power banks. (Van Mulders et al., 2022). 

Generally  speaking,  the  transmitter  receives  electricity  through  a  wire  and  transfers 
power wirelessly to the receiver, which takes up power wirelessly and provides it either 
directly or through a cable/USB connection to the device. Thus, wireless charging can 
be described as a wireless connection with power transfer between wired circuits.  

Figure 3 – Scheme of a wireless charging system 

Source: KPMG, 2024, based on Van Mulders et al., 2022 

Transmitters/receivers can be typologised according to their placement inside 
or outside the EPS/device. Inside placement means that the transmitter or receiver 
is  incorporated  in  the  product,  while  external  solutions  embrace  standalone 
transmitters or add-on receivers which can be connected through a cable or USB port 
to the EPS or device. The typology has been defined accordingly as follows:  

•  Standalone transmitters: a unit that consumers can purchase independently, 
exclusively  serving  as  a  transmitter  element  of  a  wireless  charging  system, 
where  the  device  is  ready  to  use  and  has  a  hard  case.  The  term  refers  to  a 
complete device, not a chip or a unit that needs to be integrated into a device. 
There  are  also  transmitters  which  can  be  built  into  furniture  by  consumers 
themselves  and  are  sold  separately  as  accessories.11  While  they  function  as 
embedded  transmitters  in  the  end,  these  solutions  are  considered  as 
standalone transmitters, as they can be used by end users for wireless charging 
also  without  being  integrated  into  the  furniture  piece.  This  question  was  not 
defined in the Predecessor Study, but was decided to be detailed for the present 
research. 

•  Embedded  transmitters:  Transmitter  antennas,  chips  or  coils  which  are 
integrated in the body of other equipment, like cars or furniture. Many use cases 
can be found where wireless charging is a secondary function for added user 
convenience,  e.g.  night  stands  or  lamps  with  additional  wireless  charging 
function. In the framework of the present study, transmitters are considered as 

11 IKEA: https://www.ikea.com/us/en/p/sjoemaerke-wireless-charger-80512718/, downloaded February 

01, 2024. 

45 

 
 
 
Study on wireless charging technologies 

embedded  if  the  equipment  is  already  delivered  with  an  embedded  wireless 
transmitter to end users. 

•  Add-on  receivers:  Separate  equipment  which  is  capable  of  receiving  power 
wirelessly  and  feed  it  into  the  device  circuit.  It  can  be  connected  to  a  device 
through a USB port, enabling the device for wireless charging.  

•  Embedded  receivers:  Receiver  antennas  or  coils  integrated  into  the  device 

body.  

In global regulatory context, a similar classification can be observed as used in a recent 
Federal  Proposal  of  the  Federal  Register  Vol.  88,  No.  50  (DOE,  2023)  concerning 
energy  conservation  standards  for  battery  chargers  in  the  United  States.  The  U.S. 
Department  of  Energy  (DOE)  is  differentiating  between  fixed-location  and  open-
placement  wireless  chargers,  which  are  suggested  to  be  investigated  as  separate 
product classes regarding battery energy conservation standards (DOE, 2023). 

In addition to the above mentioned types, also components like chips are available on 
the market. While theoretically, consumers could buy these parts and integrate them 
into their home devices, this is not assumed to be a typical use case for the consumer 
market as it requires specialised engineering knowledge. Therefore, the separate offer 
of wireless charging components is considered not to be relevant for the objectives of 
the present Study.  

3.2. 

Wireless charging classification 

Solutions on the wireless charging market are usually classified according to their  

• 

transfer distance range,  

•  power levels,  

•  main technology or  

•  existing standards (Table 6).  

46 

 
 
 
 
Study on wireless charging technologies 

Table 6 – Main wireless charging technologies 

Technologies and their characteristics according to relevant research literature 

Operation 
principle 

Power 
transfer 
type 

Technology  Range12 

Power 
level13 

Frequency13  Application  Standards 

Capacitive 
(CPT) 

mm / cm 

W to 
kW 

kHz to MHz 

Near-field 
/ Coupled 

Inductive 
(IPT) 

cm 

W to 
MW 

kHz to MHz 

Electro-
magnetic 
Field 
Power 

Magnetically 
coupled 
resonance  

Radio 
frequency / 
Microwave 
(RFPT) 

cm / m 

W 

kHz to MHz 

m / km 

mW / 
kW 

MHz to GHz 

Far-field / 
Uncoupled 

Laser (LPT) 

m / km 

Acoustic  

Acoustic 
(APT) 

m / cm 

W / 
kW 

mW / 
kW 

>THz 

Automotive 

Medical 
sensors 

Consumer 
electronics, 
Automotive 

Hearables, 
Wearables, 
Medical 
sensors 

Desktop 
ecosystem 

Industrial 
IoT, Smart 
home, retail 
and smart 
building 
sensors 

Space, 
Industrial, 
Military, 
Autonomous 
vehicles 

Qi, Qi2 

Magsafe 

NFC 

LEV (Light 
Electric 
Vehicles) 

Ki  

AirFuel 
Resonant 

AirPlug 

Cota 

WattUp 

AirFuel RF 

AirCord 

kHz to MHz 

Industrial 

Source: Compilation based on Detka & Górecki, 2022; Nnamdi & Asianuba, 2023; Van Mulders et al., 2022 

3.2.1. 

Distance of transfer 

Technologies of WPT can be classified by the basic physical concept they are relying 
on, thus forming  two main categories which differ in the amount of power and the 
distance of transfer. Based on literature review, the near-field vs. far-field duality is 
considered  as  most  relevant  terminology  for  the  present  Study.  The  relationship 
between  power  and  distance  is  a  fundamental  aspect  across  all  technologies, 
characterised by the adage that higher distance corresponds to lower power levels, as 
depicted in Figure 3 using Airfuel RF technology as an illustration. 

12 Considering range, power levels and frequency, unit ranges are depicted here, as these categories 
are interdependent and thus, concrete figures are influenced by the actual set-up. Rough estimates 
on figures are provided in the description of the single technologies and standards. 

47 

 
 
 
 
 
Study on wireless charging technologies 

Figure 4 – The relationship between distance and power level illustrated by Airfuel RF 
technology 

Source: Airfuel Alliance, cited by Carman (2023) 

•  Near-field  power  transfer  (non-radiative):  Transmission  of  energy  is 
implemented using a magnetic or electric field via transmitter and receiver coils 
or capacitors. Depending on which form of near-field technology is applied, this 
method allows for higher power transfer of 5-50 W and above but only at small 
distances of some millimeters to centimeters (4E, 2019; Detka & Górecki, 2022). 

•  Far-field  power  transfer  (radiative):  Electromagnetic  waves  are  used  to 
transmit  power  over  the  air,  capable  of  covering  greater  distances  of  several 
meters  by  sending/receiving  signals 
the 
transferred power level decreases with the distance increasing, as depicted in 
Figure 3,13. Current use cases in consumer electronics imply mainly low power 
devices, like remotes, door locks and smart home IoT appliances. 

through  antennas.  Generally, 

Within  these  major  categories,  several  technologies  exist  with  different  features 
regarding range, power transfer and frequency. 

Based on the conducted interviews, wireless power standards vary in frequency: 
Qi (87 kHz – 205 kHz), Qi2 (360 kHz), Resonant (6.78 MHz), RF (920 MHz), with 

13 AirFuel Alliance refers to the inverse-square law governing this power decrease in far-field wireless 
power transfer applications, basically meaning that the power level is inversely proportional to the 
square of the distance from the power source (in this case, the RF transmitter). On the other hand, 
it  is  mentioned  on  their  homepage  that  environmental  influence  can  lead  to  varying  results.  For 
further reference, please see AirFuel Alliance, 2021d. 

48 

 
 
Study on wireless charging technologies 

upcoming  technologies  expected  at  even  higher  frequencies.  Higher  frequency 
solutions have lower alignment requirements while maintaining high efficiency in the 
wireless  charging  domain  (of  course  not  comparable  to  wired  charging  efficiency 
levels). Frequencies of standards developed by standardisation organisations are not 
generally  valid  for  their  relevant  technology,  but  for  reference,  these  standards  and 
their main features will be repeated in the technology review below. 

Considering range, power levels and frequency, general statements are made here, 
as these categories are interdependent and thus, concrete figures are influenced by 
the actual set-up, not only by the technology they are based upon. Technologies bear 
with general potential regarding these features, which is therefore covered high-level 
at this point. See Table 6 and Figure 3 for reference on ranges of distance (near-field, 
mid-range, low-field), power (low vs. high power level) and frequency levels. 

3.2.2. 

Main technologies 

•  Capacitive  Power  Transfer  (CPT):  This  method  utilises  an  electric  field 
between  two  metal  plates  to  transmit  power  between  devices.  The  field  is 
generated  through  capacitive  coupling  between  the  transmitter  and  receiver 
represented  by  two  metal  covers  (plates)  of  a  flat  capacitor  without  a  direct 
electrical connection. The use of metal plates reduces costs along with a lower 
construction  complexity.  With  a  small  size,  it  allows  for  application  in  various 
use cases like medical implants, and occasionally in automotive industries (Van 
Mulders  et  al.,  2022).  Though  it  needs  to  be  mentioned  that  small-size 
applications in medical fields usually come with low power (e.g., below 1 W), 
while  smartphones  would  need  a  higher  power  level  (above  1  W,  the  actual 
power  need  of  the  device  depends  on  the  brand,  the  device’s  technical 
specifications  and  battery  design).  Increasing  the  size  of  the  metal  plates  or 
raising the frequency can enhance the charging performance, but there are too 
many influencing factors affecting the capacitor’s two plates: humidity, distance, 
material of the insulating layer, temperature. Further, the increased plate size 
might be not viable for smartphones, as it was also found in the Predecessor 
Study.  According  to  research,  CPT  was  earlier  found  to  be  an  attractive  and 
cost-efficient  alternative  to  inductive  charging  for  portable  devices  like  smart 
phones (Kline et al., 2011). However, no significant development seems to have 
been made in this direction. While having a similarenergy transfer efficiency like 
IPT in specific applications14 and a shorter transmission distance (max 100 mm) 
compared to other wireless power transfer methods (Detka & Górecki, 2022), it 
remains  an  area  of  ongoing  development  due  to  its  potential  for  high  power 

14 Regarding consumer electronics, CPT efficiency is ranging between 42,7% and 93,5% for different 

types of applications, e.g. LED lighting or mobile phones (Erel et al., 2022). 

49 

 
Study on wireless charging technologies 

• 

transmission. According to latest research, power levels are increasing15 with 
the number and size of plates, with the main implementation field being electric 
vehicle  charging  (Kodeeswaran  et  al.,  2023).  Other  advantages  include 
avoiding  unwanted  Eddy  currents  and  reducing  electromagnetic  interference 
that come with magnetic-based wireless power transfer methods (Van Mulders 
et al., 2022). 

Inductive  Power  Transfer  (IPT):  Inductive  charging  technology  uses  the 
principle of magnetic induction to transfer energy from a primary coil (source) 
to  a  secondary  coil  (device)  without  a  direct  electrical  connection.  It  is  highly 
efficient (50-80% energy efficiency in general, strongly depending on the actual 
setup  of  the  charging  system,  situational  and  environmental  factors)  but  can 
only transmit power within a  very short distance range (a few millimeters) 
Detka & Górecki, 2022). Further, it requires accurate alignment and is assumed 
by  some  of  the  interviewed  stakeholders  to  be  sometimes  more  expensive 
compared to other techniques, , especially when designed with special material 
like Litz-wire or designs like multi-coil arrangement. The short range of charging 
and  the  required  precise  alignment  may  reduce  the  customer  experience. 
However, with the spread of wireless charging and magnetic attachment as 
found in  Qi2 or  MagSafe technology,  this  concern  might  be  solved. Inductive 
charging is increasingly favored due to its efficiency in power conversion 
and low health risks (Nnamdi & Asianuba, 2023, Van Mulders et al., 2022). 
The amount of power transferred to a load is proportional to the flux density (flux 
per unit area) in the load coil. (Agbinya, 2020). Higher power transfer can be 
achieved  by  increased  coil  size,  reducing  the  distance  between  the  coils, 
optimising the coil shape, and increasing the quality factor or using better-quality 
wire  for  the  coils.  For  systems  with  multiple  transmitter  and  receiver  coils, 
magnetic  beam  forming16  can  help  in  enhancing  power  transfer  efficiency. 
However,  as  power  levels  increase,  challenges  such  as  heat  dissipation, 
electromagnetic  compatibility,  and  maintaining  system  safety  become  more 
important.(Detka  &  Górecki,  2022,  Van  Mulders  et  al.,  2022).  The  MagSafe 
technology developed by Apple is mitigating the challenge of precise alignment 
by  embedding  magnets  into  the  devices,  which  snap  onto  standalone 
transmitter pads and keep devices just at the right spot for efficient charging. 
This  advancement  has  been  adapted  in  the  newest  generation  of  the  Qi2 
standard, available since the end of 2023 on consumer markets (Ryles, 2023). 
Another  recent  development  embraces  omnidirectional  charging  around  the 
transmitter,  aiming  for  more  spatial  freedom.  This  was  reached  in  a  proof-of-
concept  design  with  cylindrical  coils,  but  still  needs  safety  testing  before 

15  Power  levels  of  course  vary  with  use  case,  but  for  electric  vehicles,  power  levels  of  prototype 

capacitive WPT are ranging from 800 W to 3.7 kW (Maji et al., 2020). 

16  Beamforming  in  inductive  wireless  power  transfer  aims  to  address  energy  efficiency  issues  by 
dynamically  adjusting  the  magnetic  field  to  focus  it  more  precisely  towards  the  receiver  coil. 
(Kisseleff et al., 2015) 

50 

 
Study on wireless charging technologies 

implementation (Ha-Van et al., 2022). The main standard for inductive charging 
concerning  consumer  electronics  is  the  Qi  standard,  with  frequency  ranging 
from  97  kHz  to  360  kHz.  More  features  of  the  standards  are  detailed  in  the 
“standards” section. 

•  Magnetic Resonance Power Transfer (MRPT): Magnetic Resonant wireless 
charging  technology  enables  efficient  energy  transfer  over  mid-range17 
distances, delivering power even with positional and orientational offsets. Power 
is  transferred  between  two  coils  resonating  at  the  same  frequency  (Ayir, 
2023). The source resonator generates a magnetic field that interacts with the 
device  resonator  when  placed  in  proximity,  leading  to  the  accumulation  of 
energy.  This  energy  is  then  transferred  from  the  device  resonator  to  directly 
power a load or recharge a battery (Kesler, 2021). The technology (e.g. used 
as AirFuel Resonant, see Detka & Górecki, 2022) is scalable and cost-effective 
compared to other WPT methods. As MRPT does not require proper alignment 
like IPT, it provides more spatial and design freedom. Notably, the technology 
also allows for energy transmission over several meters, unlike traditional IPT 
techniques.  It  is  further  capable  of  simultaneously  charging  multiple  devices 
(AirFuel Alliance, 2021). MRPT usually has a lower transmission efficiency 
than IPT due to losses from eddy currents (Detka & Górecki, 2022).There are 
ways to raise efficiency, and there have been applications with an impressive 
94% end to end efficiency according to literature (Kesler, 2021), but only in high 
power  use  cases  which  are  out  of  scope regarding  the  present  Study.  Some 
experts  regard  resonant  charging  using  different  frequencies  and  magnetic 
alignment  as  a  stronger  competitor  to  inductive  charging  compared  to  other 
methods such as RF. It is used in diverse sectors  like automotive for electric 
vehicle charging, medical applications and even consumer electronics (Detka & 
Górecki, 2022), though for the latter one, no use cases could be found on the 
market.  The  main  standard  specification  for  MRPT  is  former  A4WP,  now  Air 
Fuel Alliance’s Airfuel Resonant standard operating on a frequency of 6.78 MHz. 
Further features of the standards will be detailed in the “standards” section. 

RF radiation Power Transfer (RFPT): RF wireless charging technology uses 
radio frequency (RF) to transmit electromagnetic signals over both long and 
short  distances.  This  technology  involves  a  system  that  can  receive  and 
transform  electromagnetic  energy  into  useful  direct  current  (DC)  voltage, 
primarily through an antenna and a rectifier circuit. RFPT systems often include 
energy  harvesting  capabilities,  using  ambient  energy  radiated  from  other 
equipment which otherwise would turn into a loss (Ayir, 2023; Van Mulders et 
al., 2022). RF wireless charging is particularly advantageous due to its ability to 
travel  long  distances  (up  to  several  meters),  penetrate  through  walls,  and 
provide data communication without requiring a definite path, thus resulting in 
“truly  wireless”  experience  (Nnamdi  &  Asianuba,  2023).  It  is  capable  of 
charging multiple devices simultaneously over the air due to lower alignment 

17 For reference on approximate figures of midrange, see Figure 3 and Table 6. 

51 

 
Study on wireless charging technologies 

requirements, with an “omnipresence” similar to the signals emitted by a WiFi 
router. On the other hand, the broadcasting of power also means that emitted 
power which is not received by a device turns into energy loss, although small 
amounts as it is usually operating on low-power levels from several mW up 
to 1 W (Van Mulders et al., 2022). Higher levels of radiation can cause health 
problems when getting in contact with or traveling through human (or animal) 
tissue. Therefore, strict regulations apply to RF charging, allowing it to send 
only  very  small  amounts  of  power  by  restricting  frequency.  RF  technology  is 
currently  appropriate  for  applications  that  require  less  than  1  Watt  of  power. 
RFPT also needs to comply with national radio regulations and usually may 
operate on designated frequency bands to avoid interferences with other radio 
equipment  (Directive  2014/30/EU;  ITU-R,  2017).  It  is  considered  safer  with 
virtually  harmless  radio  frequencies  to  humans  because  of  its  low  electrical 
energy (AirFuel Alliance, 2021b, ITU-R, 2022). Thus, RFPT is particularly useful 
for constant supply of low power below 1 W where wired charging is not possible 
(e.g. in unmanned ships or due to weather conditions) or less economic due to 
amortisation of cables, e.g. in the medical field, harsh industrial environments, 
and  in  powering  IoT  (Detka  &  Górecki,  2022).  Use  cases  are  increasingly 
emerging also for low-power portable devices. RF technology's potential lies in 
a  market  surpassing  cell  phones  and  consumer  electronics,  especially  in  IoT 
devices  smart  home,  retail  and  energy  harvesting  applications.  A  specified 
standard for RF is the Airfuel RF standard, operating on 920 MHz frequency. 
Further details on its features can be found in the “standards” section. 

•  Laser  Power  Transfer  (LPT):  Laser  wireless  charging  technology  utilises 
concentrated  laser  light  directed  at  the  energy  receiver,  usually  photovoltaic 
panels,  for  high-efficiency  power  transmission  over  very  long  distances. 
Currently, use cases embrace aerospace solutions involving satellites, e.g., a 
prototype by the British company Space Power with a planned commercialised 
launch in 2025. The use of laser beams marks a disadvantage of LPT, as it is 
more influenced by weather conditions and atmospheric absorption, while laser 
radiation can be dangerous for people and the environment (Detka & Górecki, 
2022). Thus, it is required to have monitoring systems. Some companies like 
WiCharge (using infrared light) and PowerLight Technologies have made use 
of  this  wireless  charging  technology,  demonstrating  its  potential  in  various 
applications like IoT equipment, 5G infrastructure, and space solutions. Beside 
industrial  use,  portable  devices  like  Qi  chargers,  power  banks  or  game 
equipment can be supplied with a small USB external receiver (Van Mulders et 
al.,  2022).  The  technology  is  also  capable  of  transferring  energy  to  moving 
receivers  and  to  multiple  receivers  simultaneously  through  multiple  beams. 
Based on the literature, the main usage of this technology currently seems to 
lay in industrial sectors. 

•  Acoustic energy transfer (AET): Acoustic Energy Transfer technology as the 
only  WPT  solution  which  is  not  based  on  electromagnetism  uses  sound  or 
vibration waves to transmit power (Awal et al., 2016). AET is advantageous in 
situations  where  device  miniaturisation  is  required  or  where  electromagnetic-

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Study on wireless charging technologies 

based power transfer is complicated due to metallic shielding. The technology 
is also beneficial in environments where strong electromagnetic fields should be 
avoided for health or safety reasons. However, AET is limited in research as it 
faces challenges such as high absorption in air and limitation in power18 due to 
regulatory  limited  exposure  to  the  human  body(Van  Mulders  et  al.,  2022) 
Despite  its  drawbacks,  AET  holds  promise  for  applications  in  areas  like  IoT, 
biomedical fields, and situations requiring power transmission through enclosed 
metallic  walls.  Regarding  its  characteristics  and  based  on  the  reviewed 
literature,  AET  is  currently  not  adapted  in  portable  consumer  electronics  like 
smartphones. 

While each of the technologies listed above has its drawbacks and limitations, some 
of the interviewed experts who are mostly active in the RFPT field predict – in order to 
achieve a high level of user convenience – an ultimate home solution that continuously 
feeds  power  to  multiple  devices.  However,  the  deployment  of  such  wireless  power 
supply is quite expensive for the time being, on the other hand, the power level is very 
low  but  constant.  A  good  solution  might  be  the  emerging  technique  of  energy 
harvesting, where devices harness small amounts of power from existing signals (e.g., 
Wi-Fi) without the need of adding new technology. 

Among the above mentioned solutions, wireless charging with 

• 

inductive coupling,  

•  magnetic resonance 

•  and RF 

have evolved as main categories with a growing range of use cases in industrial as 
well as consumer fields and are thus considered as most relevant for the present Study 
(4E, 2019; Nnamdi & Asianuba, 2023).  

3.2.3. 

Standards  

Reasons and impact of standardisation 

Standards  and  specifications  are  introduced  for  wireless  charging  to  ensure 
compatibility  and  interoperability  across  devices  and  chargers.  Interoperability 
challenges  exist  due  to  the  need  for  different  antennas  and  frequency  bands  for 
different  technologies.  Unlike  wired  charging,  where  interoperability  has  remarkably 
improved, the wireless charging market still has room for improvement and lacks 

18  Considering  range,  power  levels  and  frequency,  general  statements  are  made  here,  as  these 
categories are interdependent and thus, concrete figures are influenced by the actual set-up, not 
only by the technology they are based upon. Technologies bear with general potential regarding 
these features, which is therefore covered high-level at this point. For reference, see Table 6. 

53 

 
Study on wireless charging technologies 

the  same  level  of  standardisation  and  compatibility.  Customer  concerns  over 
backward compatibility complexities and energy output differences between wired and 
wireless chargers can be experienced. Industry standards make it possible for various 
devices  to  work  seamlessly  with  different  chargers,  allowing  a  faster  adoption  of 
wireless charging in the market (AirFuel Alliance, 2024; Infineon, 2023). Furthermore, 
standards  and  specifications  provide  guidelines  to  ensure  safety,  efficiency,  and 
reliability of wireless charging technology regarding power levels and operation not 
causing  harm  in  devices.  Devices  and  transmitters  need  to  undergo  a  specific 
certification test procedure to officially be recognised as operating under the given 
standard. These rigorous processes are surveilled by the founding organisation of the 
given  standard  and  ensure  compliance  with  regulations  as  well  as  enhanced  user 
experience and safety (WPC, 2024a and 2024b). There are still many white-labelled 
and  uncertified  (inductive)  products  on  the  market  with  attractive  prices,  but 
potentially  lacking  safety  measures  like  foreign  object  detection.  Unlabelled  or 
mischievably labelled products seem to represent a submarket with different dynamics 
and preferences, further very difficult to measure objectively due to missing data and 
transparency.  Thus,  these  products  are  not  part  of  the  present  Study’s  scope,  any 
statement presented in the following refers only to officially certified products. 

Specific standards are set for different applications of wireless power transfer such as 
for  portable  electronics  like  smartphones,  further  for  kitchen  appliances  (WPC, 
2024d),19 light electric vehicles, and industrial battery-powered vehicles which are less 
relevant for the present Study as they operate on power levels beyond 240 W. These 
standards may vary based on power transfer capacity, operating frequency, and other 
parameters  (van  Mulders  et  al.,  2022).  That  said,  it  needs  to  be  emphasised  that 
presently, no “one size fits all” standard can be identified. The choice of a specific 
wireless  charging  standard  seems  to  be  much  influenced  by  the  shape,  size  and 
purpose of the given device, which may exclude some technologies as options just 
due to its physics. This leads to an organic fragmentation of the market by device 
type, which seems to be more difficult to bridge by regulatory steps than compared to 
wired  charging.  Standards  therefore  serve  the  purpose  of  interoperability  within 
specific  technologies,  e.g.  Qi  creating  a  common  baseline  for  inductive  wireless 
charging mainly for phones, but not being interoperable with RF charging methods by 
default.  

Based on experts opinion, main objectives of WPT market regulation and potential 
standardisation aspirations are: 

•  mitigating heat dissipation and energy efficiency issues of power 

transmission; 

•  reducing energy waste; 

19  According  to  WPC's  Ki  cordless  kitchen  standard,  the  technology  utilizes  inductive  WPT  which  is 

regarded as real wireless. 

54 

 
Study on wireless charging technologies 

•  reducing customer waste at scale coming from frequent replacement of 

chargers and cables: with wireless charging, experts believe that protection of 
the environment can be enhanced as likelihood of wear-and-tear amortisation 
of cables or devices decreases;  

• 

limit electromagnetic interference from electrical appliances by 
standardising around specific frequency bands; 

•  ensuring user safety during usage; e.g. with safety standards concerning 

foreign object detection in order to not heat up any metal objects accidentally 
thrown on inductive chargers. 

•  enabling interoperability among different manufacturers, brands and 
chargers, charging multiple devices, and backwards compatibility; 

Main standards and their features 

Before describing single technologies in detail, it is worth emphasising that based on 
expert interviews, in general, market-leading manufacturers have first to be convinced 
of a specific technology or standard, they are key to rapid widespread and success. 
When  influential  companies  adopt  a  technology,  it  greatly  promotes  market 
acceptance, generating widespread consumer interest and adoption.  

A couple of examples for market connections according to the interviews: 

• 

• 

Influence  of  the  Automotive  Industry:  The  integration  of  wireless  charging 
transmitters  within  cars  by  various  manufacturers  boosts  the  appeal  and 
convenience of wireless charging. 

Influence  of  powerful  market  players  on  standards  further  contributing  to 
technological advancement and industry adoption. 

•  The  Wireless  Power  Consortium's  industry  network  and  continuous 
improvement efforts, such as implementing foreign object detection features to 
prevent  damage  caused  by  non-compliant  accessories,  are  instrumental  in 
maintaining Qi's standardisation and reliability. 

The  three  wireless  charging  standards  mainly  discussed  concerning  consumer 
appliances are Qi, NFC, and AirFuel Alliance, coming with different features. These 
were  selected  based  onthe  fact  that  these  are  standards  developed  by  the  main 
industry alliances for wireless charging (see 3.1.). 

Qi 

This  standard  developed  by  the  Wireless  Power  Consortium  (WPC)  and  initially 
released in 2010 is currently the most widely adopted wireless charging standard 
in small portable consumer electronics, especially smartphones. It is supported 

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Study on wireless charging technologies 

by  more  than  600  companies  with  over  9000  products  (WPC,  2024c).  Based  on 
inductive  coupling  requiring  a  tightly  coupled  transmit-receive  system,  Qi  is  most 
suitable with flat surfaces, resulting in the recognisable flat design of Qi chargers with 
a  transmitter  coil  diameter  typically  between  30-50  mm.  In  standard  1-coil  designs, 
devices need to be perfectly aligned for optimal power transfer, which can be mitigated 
with  multiple  coils  in  the transmitter.  The  latest  version of  Qi released  at  the  end  of 
2023, Qi2 includes magnets (as seen in the MagSafe technology by Apple), ensuring 
better alignment. Further, Qi2 is able to operate 360 kHz frequency level too, which is 
higher compared to the former versions (87-205 kHz). . According to expert interviews, 
special  attention  is  given  to  backward  compatibility  between  Qi2  and  Qi  chargers, 
though this faces some limitations and might be dependent to the actual device used 
by the consumer. As mentioned on the WPC’s website, there is no 100% backwards 
compatibility requirement with former versions for Qi2 certified products (WPC, 2024g). 
However,  Qi1  standard  receivers  can  achieve  compatibility  with  Qi2  transmitters 
through  a  multi-step  process.  Qi2  backward  compatibility  is  ensured  through 
communication  between  transmitter  and  receiver,  where  charging  begins  in  Qi1 
standard  (87-205kHz)  and  switches  to  Qi2  (360kHz)  upon  receiver  indication. 
Therefore, it is possible for Qi2 to operate with lower frequency level as well.  

The  transmitted  power  typically  ranges  from  5W  to  15W  with  the  following  power 
profiles: 

•  Baseline Power Profile (BPP, released in 2010) – ≤ 5 W, unidirectional 

communication protocol (Baseline Protocol). 

•  Extended Power Profile (EPP, released in 2015) – up to 15 W, introduced 
with the Qi version 1.2. Its architecture would theoretically allow for 30 W, 
which is currently not available (WPC, 2021). 

•  Magnetic Power Profile (MPP, released in 2023) – a technology used in the 
newest Qi2 generation with perfect alignment of devices and chargers for 
improved energy efficiency, faster charging, and easier usability (WPC, 
2024c). 

Qi  chargers  include  a  communication  channel  between  transmitter  and  receiver  to 
identify compatibility and power needs of the device. This also ensures interoperability 
between BPP and EPP products, e.g. a device designed for receiving 15 W power will 
allow for slower charging when coupled with a 5 W charger (WPC, 2021).  

Regarding  interoperability,  products  can  only  use  the  Qi  logo  if  they  pass  a  Qi 
certification test developed by WPC. Every transmitter is tested with a whole range 
of receivers and conversely. Thus, WPC guarantees that Qi-labelled products on the 
market are compatible and interchangeable, ensuring interoperability. WPC maintains 
a public database of products tested for the Qi standard. Backwards compatibility is a 
mandatory  requirement  and  guaranteed  for  all  devices  tested  according  to  the  Qi 
standard (though not required to 100% for Qi2).  

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Study on wireless charging technologies 

The Qi specification also  requires foreign object detection with proper information 
shared by the receiver to avoid heating up other electrically conductive materials (e.g. 
coins, keys, etc.) placed on the charger.  

Qi chargers appear most commonly as desktop chargers (charging pad or stand), 
but there are also applications as power banks or embedded versions in furniture, 
cars or small equipment like clocks or lamps (WPC, 2021). Qi charging is largely 
used  in  smartphones,  and  in  some  cases  also  withother  mobile  devices  like  for 
smartwatches and earbuds (though the proportion of proprietary solutions is higher in 
these product categories due to shape and size factors). 

The  pivotal  issue  of  standardisation  is  determining  the  appropriate  timing  and 
assessing  Qi’s  potential  to  become  the  dominant  market  leader.  There  has  been  a 
historic  delay  in  Qi  technology  adoption  since  manufacturers  were  uncertain  about 
which  standard  would  prevail.  Manufacturers  had  previously  directed  their  efforts 
towards developing various USB standards like USB-A, USB-B, and USB-C. Now, with 
mobile  phones  driving  Qi's  relevance,  there  is  a  clear  market  opportunity,  although 
hesitation  remains  concerning  technological  innovation  being  hindered  by  rigid 
standardisation. 

Despite recognising Qi technology's market potential and witnessing its increased ease 
and  affordability  of  integration  for  manufacturers,  some  technology  experts  remain 
uncertain about its future. This may be connected to the fact that while it has evolved 
as de facto market standard for smartphones, its application for smaller or custom 
shaped  equipment  is  still  limited  by  technological  factors.  Thus,  it  is  unable  to 
serve  as  universal  “one  size  fits  all”  standard  for  different  consumer  electronics  at 
present. This also signs a weakness compared to wired charging, which is expected 
to be interoperable for several device types since the harmonisation of the charging 
solution (USB-C and USB PD) in the EU. The lack of ubiquitious application of Qi may 
still  drive  some  companies  and  retailers  to  push  innovation  efforts  for  universally 
applicable  solutions,  e.g.  with  RF  charging.  For  some  use  cases,  manufacturers 
therefore tend to prefer the proprietary solutions over standardised ones, impacting the 
rapid adoption of Qi in the market. A good example a smartwatches, which come with 
many challenges to adopting Qi due to their limited size and different functionalities. 

Although  being  aware  of  weaknesses  of  Qi  technology  (e.g.  strict  alignment 
requirements, lower power transmission compared to wired charging, short charging 
distance),  the  vast  majority  of  the  interviewed  experts  and  top  managers  of  market 
leading  companies  currently  does  not  anticipate  a  competing  solution  to  show  up, 
neither do they expect a revolutionary breakthrough in wireless technology.  

Qi’s  integration  into  devices  has  become  more  cost-effective  and  user-friendly, 
streamlining the manufacturing process and enhancing the charging experience. An 
established supply chain keeps component costs low and adoption feasible. Despite 
slower  speeds  compared  to  wired  charging,  Qi  is  seen  to  evolve  as  de  facto 
predominant  standard  for  wireless  charging  for  smartphones,  especially  with 
advancements like the new Qi2 version improving alignment and efficiency. 

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Study on wireless charging technologies 

Product types which currently support Qi are listed in the Product database in chapter 
5. Some experts assume that form factor issues could be mitigated  in the future by 
custom  shaped  charging  cases  with  a  flat  outer  surface,  similar  to  examples  with 
wireless earbuds. 

Competing  market  players  and  manufacturers  who  are  working  together  on 
improvement of Qi seem not to be considering to launch their own different standards. 
Potential  alternative  standards  could  therefore  mainly  come  from  companies  using 
other technologies or specialising on different use cases than smartphones. 

However,  major  manufacturers  keep  participating  in  the  Qi  standardisation  process 
and applying the Qi certification scheme. This fact can motivate other market players 
to incorporate Qi technology into their devices.  

NFC (Near Field Communication) 

This specification developed by the NFC Forum  leverages capabilities of the NFC 
technology which is widely implemented in smartphones and similar portable devices 
for data transfer. It is based on inductive coupling using small NFC antennas and 
operates  at  a  high  frequency  of  13.56  MHz.  NFC  wireless  charging,  unlike  Qi 
technology, enables its embedding within small spaces rather than using a large 
flat disc-like design. Therefore, alignment of device and transmitter is less important, 
offering more spatial freedom in the orientation of the device compared to Qi charging. 
However, transmission distance is still quite low, currently ranging between 5 mm 
and 2 cm (NFCForum, 2023b and 2024).  

Consumers usually seek solutions to charge devices over a longer period and longer 
distances. Although NFC is an already existing solution on the market, it is only suitable 
for  very  short  distances  (similar  to  Qi,  though  providing  some  more  millimeters  of 
spatial freedom) and with low power transmission of currently up to 1 W. 

The NFC technology works in a more complex ecosystem that includes three different 
players  and  their  contribution:  chip  provider,  operating  system  provider,  and 
device manufacturer, all necessary for enabling NFC wireless charging on a device. 
NFC wireless charging capability relies on mutual agreement and implementation by 
all three ecosystem players. 

The  14  mm  diameter  of  the  transmitter  makes  NFC  the  smallest  inductive 
technology on the market, giving freedom to product design. With its charging power 
levels of up to 1W, it is thus best suitable for small low-power devices, e.g. wireless 
earbuds,  smartwatches,  digital  styluses,  headsets,  and  fitness  trackers  (McCamon, 
2023). Items on the agenda of the NFC Forum until 2028 are increased power levels 
(up  to  3  W)  and  an  operating  range  of  four  to  six  times  the  current  distance  (NFC 
Forum, 2023). 

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Study on wireless charging technologies 

For  now,  NFC  wireless  charging  is  primarily  planned  and  designed  for  embedded 
systems, aiming to replace wired connection ports within devices. 

Based on the opinion of an expert dealing in detail with NFC technology, not all NFC-
enabled devices support wireless charging due to technical considerations and device 
design limitations. 

Unlike  others,  NFC  not  only  allows  for  wireless  charging  but  also  data  transfer 
between devices and energy harvesting using the same transmitter antenna. Another 
differentiating  feature  is  the  capability  of  encryption,  enhancing  security  of  data 
transfer. Like Qi, the NFC specification is considered an open standard, promoting 
collaboration and greater interoperability (McCamon, 2023, NFC Forum, 2023). 

The NFC Forum predicts the largest volume of NFC wireless charging will especially 
be embedded use cases such as smaller devices like earbuds, due to the benefits of 
reliability, cost savings and isolation. 

For  some  use  cases,  manufacturers  tend  to  prefer  the  proprietary  solutions  over 
standardised  ones,  impacting  the  rapid  adoption  of  NFC  wireless  charging  in  the 
market. This attitude is similar to the case of the Qi standard mentioned above. 

The NFC Forum is monitoring regulatory activities, especially in the context of wireless 
technologies like NFC. However, presently, there does not seem to be any significant 
concerns on the horison. 

AirFuel Alliance 

The AirFuel Alliance regroup mostly companies with resonant and RF solutions. It 
released  specification  in  both  fields,  with  the  AirFuel  Resonant  standard  being 
available earlier, and an AirFuel RF certification program recently launched in January 
2024. 

AirFuel Resonant standard covers up to 50W of power leveraging resonant inductive 
coupling, enabling a wider range of use cases, e.g. powering laptops. Similarly to Qi, 
it is surfaced based but capable of simultaneously charging multiple devices without 
precise alignment at higher speeds. It operates at a frequency of 6.78 MHz, allowing 
for larger operational ranges (up to 50mm) compared to Qi-enabled devices. The 
high  frequency  also  comes  with  different  features,  like  reaching  high-quality  results 
with  more  cost-efficient  materials  for  the  coil  while  reducing  energy  loss  from  eddy 
currents,  which  also  means  metals  of  foreign  object  do  not  heat  up.  The  6.78  MHz 
frequency  is  further  a  regulated  ISM  (Industrial-Scientific-Medical)  frequency 
band20.  This  technology  also  incorporates  use  of  Bluetooth  Low  Energy  (BLE)  for 

20 ISM bands are internationally reserved for industrial, scientific and medical applications, which means 
that they are not used for telecommunication applications and therefore do not interfere with any 
consumer telecommunication device. 

59 

 
Study on wireless charging technologies 

communication between receiver and transmitter at 2.4 GHZ. (AirFuel Alliance, 2021c). 
While  having  many  benefits,  this  resonant  standard  can  be  found  in  few  products 
(Van  Mulders  et  al.,  2022)  such  as  eBikes  and  e-scooters21,  which  undermines 
earlier assumptions that resonant technology will rather find its own niche of use cases, 
e.g.  in  GaN  component  manufacturing  (Bonnabel  &  Rosina,  2018;  Clark,  2018). 
Although  the  AirFuel  Resonant  standard  enables  the  wireless  charging  of  larger 
devices such as laptops or tablets, further development is still required.  

AirFuel  RF  standard  was  released  in  January  2023  as  global  standard,  with  a 
certification  program  launched  in  January  2024  (AirFuel  Alliance,  2024).  It  uses 
radio frequency waves to transfer energy wirelessly across distances ranging from 
a few centimeters up to a few meters, creating an ambient energy zone where power 
can be harvested by devices. As power levels decrease with a greater distance, the 
standard is best suitable for low-power devices at large scale, such as IoT Sensors. 
Being capable of simultaneously charging multiple devices in a three-dimensional 
range, it does not require precise placement. As antennas are very small, the AirFuel 
RF standard has a good potential of implementation in small devices, allowing for cable 
and potentially even battery elimination with constant powering, placement flexibility, 
and  maintenance  avoidance  (AirFuel  Alliance,  2021d,  EverythingRF,  2023).  The 
envisioned use cases mainly belong to the industrial sector, but also embrace small 
personal electronics like wearables.  

As the standard is quite new, specific quantitative results relating to power levels and 
detailed  technical  specifications,  such  as  maximum  transmitted  power  or  efficiency 
rates, are not detailed in the accessible documents. However, the alliance members 
are  optimistic  about  the  potential  of  this  technology  to  address  unique  use  cases 
previously  unaddressable  by  RF-based  wireless  power,  expecting  more  devices  to 
integrate RF charging (AirFuel Alliance, 2021d). The standard could offer a universal 
power  source  for  designers  to  streamline  current  designs  or  inspire  new  creative 
solutions (Carman, 2023). 

3.2.4. 

Proprietary technology, new standards and 
coexistence of standards 

According  to  some  experts,  various  proprietary  solutions  are  emerging  that 
contribute to technological growth and development, but, for the majority of them, the 
time  is  not  yet  right  for  their  standardisation.  Developed  by  innovative  companies, 
these  technologies  offer  diverse  solutions  with  specific  range  and  power  level 
characteristics,  addressing  various  use  cases  and  preferences  in  the  wireless 
charging  landscape.  Some  are  envisioning  to  form  new  standards  in  the  future, 
however, at the present they are represented only by their developing company. There 
is no complete agreement among experts that we can talk about a dominant protocol 

21 https://airfuel.org/zh/bumblebee-powers-wireless-charging-solution-for-shared-e-scooters/; 

https://airfuel.org/zh/powering-micromobility-solutions-with-airfuel-resonant/ 

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Study on wireless charging technologies 

or standard, yet. According to the majority of persons interviewed, the Qi standard has 
already reached an essential dominance on the smartphone market which is basically 
not  disruptable  while  others  envision  some  proprietary  technologies  capable  of 
generating  new  standards,  though  probably  rather  in  other  product  categories  than 
smartphones.  Therefore,  a  coexistence  of  several  standards  and  an  organic 
fragmentation based on physical features of the charged device could be seen in 
this scenario.  

The following proprietary solutions or alternative standards have been identified: 

Inductive PT 

MagSafe  (Apple):  MagSafe  utilises  inductive  charging  with  magnet  positioning  for 
seamless  device  attachment,  operating  in  close  proximity,  typically  within  a  few 
millimeters  to  centimeters.  It  supports  lower  to  medium  power  requirements,  with 
typical power levels around 15 watts (MagSafe 15W charger). Primarily designed for 
Apple  devices  like  iPhones  and  AirPods,  MagSafe's  benefits  include  easy  device 
alignment  with  magnetic  attachment.  However,  it  is  constrained  by  its  exclusive 
compatibility  within  the  Apple  ecosystem  and  its  shorter  charging  range.  The 
magnetic attachment technology has been adopted by WPC in 2023, forming the new 
Qi2  standard.  (Jary,  2023).  It  is  foreseen  by  experts  that  MagSafe  will  continue  to 
coexist alongside Qi2 as branded solution for Apple devices.  

Ki Kitchen Cordless (WPC) Ki Kitchen Cordless is a specific application of the WPC 
standard tailored for cordless kitchen appliances. It utilises inductive charging with a 
short  to  mid-range  transfer  distance.  The  power  levels  are  adapted  to  suit  the 
requirements of kitchen devices reach up to 2200 W. The standard is currently under 
development.  (WPC,  2024)22.  The  advantage  lies  in  the  wireless  and  hassle-free 
charging  of  kitchen  appliances  like  juicers,  blenders,  kettles  (WPC,  2024d),  but 
limitations may include the need for dedicated charging pads and potential constraints 
in device compatibility. 

LEV  Light  Electric  Vehicle  (WPC)  The  LEV  standard  within  the  WPC  focuses  on 
wireless charging for light electric vehicles like scooters or e-bikes. This standard is 
designed to  provide  fast, smart, efficient  and  high power  level  charging  required  for 
efficiently  charging  mobility  devices.  It  typically  employs  inductive  or  resonant 
charging technologies and may have longer transfer distances compared to consumer 
electronics  applications.  The  specification  is  being  defined  by  representants  of  the 
industry to ensure interoperability. (WPC, 2024e). 

22  According  to  the  WPC,  “efficiency  Ki  Cordless  Kitchen  appliances  are  required  to  operate  at 
efficiencies  greater  than  90%  of  equivalent  appliances  that  use  power  cords.  The  difference  in 
usable power is negligible and is unlikely to be noticed in daily usage” (WPC, 2023b). Notably, the 
term “energy efficiency” is different for this type of application than for battery charging, as energy 
is not stored but immediately used in equipment that have no battery. 

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Study on wireless charging technologies 

RFPT 

The actual state of RFPT is difficult to measure, as several proof-of concept designs 
have  showcased  solutions  which  seem  to  be  technically  viable.  Still,  the  market 
penetration of these technologies remains minimal, as basically no products can 
be  found  for  consumer  use  beside  from  industrial  applications  with  very  low  power 
delivering at microwatt level. According to a review accessible on WPC’s website, the 
issue may be economical viability. While these innovative concepts deal with functional 
requirements (transfer distance, power level, spatial freedom), they still lack market-
readiness in non-functional aspects (safety, radio-frequency interference, efficiency of 
power transfer and cost). (Treffers, 2021). On the other hand, manufacturers of RF-
based transmitters remain confident, with some mentioning go-to market plans for the 
coming period, without an exact timeline. 

WattUp (Energous): WattUp employs Radio Frequency (RF) technology for charging, 
boasting  a  transfer  distance  which  can  cover  large  industrial  and  retail  spaces  if 
combined as a power network system. WattUp accommodates various power levels, 
typically  in  the  range  of  a  few  watts,  with  a  significant  development  of  reaching  the 
FCC approved 15 W power level in 2022. Its listed use cases remain industrial, lying 
mainly in powering IoT Sensors, RFID tags and small retail accessories (Energous, 
2022). Also, beside the press release of the FCC approved power level increase, no 
recent consumer use cases or actual products targeting the consumer market could 
be identified. Therefore, it was decided to list WattUp among the proprietary standards, 
which represents a difference compared to the Predecessor Study handling WattUp 
among major standards. 

Cota (Ossia): Cota implements Over-the-Air charging using RF, covering a mid-range 
distance  of  up  to  ca.  9  meters,  also  in  motion.  Power  is  sent  simultaneously  to 
receiving devices by a transmitter, also including data transfer between transmitter and 
receiver for optimal power transmission. The technology differentiates by its use of a 
to  RF 
multi-path  retrodirective  system,  representing  a  potential  solution 
technology’s health challenge: the signal does not go through human or animal tissue, 
thus  power  limitations  due  to  health  consideration  are  not  necessary  (Shinohara, 
2021).  Cota  is  marketed  as  versatile  for  IoT  devices,  smart  home  technologies, 
industrial applications and potentially, also for consumer electronics. The exact amount 
of power that can be transferred by Ossia's Cota technology in watts is not explicitly 
stated  in  the  accessible  sources.  Utilising  RF  technology,  its  power  levels  are  also 
depending from distance and the overall setup of the charging system and are limited 
by regulations (e.g., the FCC limitation of Specific Absorption Rate (SAR) for public 
exposure to power emitting from devices(e.g. microwave ovens, cellphones, etc.) is at 
1.6  watts  per  kilogram;  Altair,  2024).  Transmitters  currently  presented  can have the 
shape  of  a  desk  stand  or  a  ceiling  tile  similar  to  a  lamp.  (Ossia,  2024).  The  Cota 
standard can be licensed, but is not yet available on the market in products.  

AirPlug (Aeterlink): AirPlug relies on microwaves for wireless charging, operating at a 
range of typically within a few feet. Suited for low to medium power requirements, 

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around 1 watt, it finds applications in various electronic devices such as factory IoT, 
cooling and small medical devices. It also includes data transfer via cloud, enabling 
various  optimisation  possibilities  in  IoT  devices.  Its  use  cases  include  factory 
automation, medical implants and building management. No consumer electronics 
applications have been reported to date. (Aeterlink, 2020). 

Laser PT 

AirCord (Wi-Charge): AirCord utilises Infrared light technology for charging, effectively 
operating  at  distances  within  a  few  meters  but  ranging  to  10  meters.  Primarily 
designed for low to medium power requirements, around 100-300 mW, it is suitable 
for charging small electronic devices. One transmitter is capable of powering multiple 
devices across a 130 m² area, making it suitable for powering home appliances and 
devices.The non-visible light charging and compact design are beneficial features, but 
limitations include the need for direct line of sight. (Wi-Charge, 2024). 

Conductive PT 

identifies 

the  chargeable  device  and 

Power  by  Contact  (Energysquare):  Power  by  Contact,  as  implemented  by  the 
european  company  Energysquare,  relies  on  conductive  charging  through  surface 
contact. This method is an outlier regarding that though there is no cable, or USB type 
connector, the technology is considered wired charging technology because it has a 
direct physical contact with a conductive surface. Similar solutions are used through 
copper  pines  in  Bluetooth  headsets  and  low-end  smartwatches.  The  concept  of 
conductor-to-conductor connection is realised through a charging pad comprising tiles 
functioning  as  the  transmitter  and  electrodes  on  the  device  serving  as  the  receiver. 
Ultimately,  when  the  device  electrodes  are  positioned  on  the  charging  surface,  the 
transmitter 
transfer. 
(Energysquare, 2023). Though, the use of a charging pad with direct contact could be 
perceived  as  similar  to  inductive  charging  by  consumersand  its  positioning  as 
wireless  charging  might  be  reasonable  from  marketing  aspects,  it  is  not  a  wireless 
charging technology technically speaking. This technology can be applied in charging 
pads  for  smartphones,  tablets,  and  other  devices.  The  advantage  of  the  specific 
solution  by  Energysquare  lies  in  its  ability  to  offer  “wireless”  charging  with  some 
freedom provided as conductive contact can be established at several points on the 
charging mat. However, the concept still requires precise alignment but with multiple 
options, similar to a multicoil charging pad. Therefore, the solution could be perceived 
as freedom of placement by consumers and is therefore  providing a straightforward 
and efficient charging experience. Nonetheless, this form of conductive charging is not 
defined  as  wireless  charging,  as  direct  contact  is  required.The  solution  has  been 
utilised also for charging laptops of a particular brand, claiming power levels of up to 

initiates  power 

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Study on wireless charging technologies 

65 W23. However, its dependency on direct contact and the requirement for compatible 
conductive surfaces are limitations which need to be considered for suitable use cases, 
similar to inductive methods.  

Trends and potential of coexistence of standards 

Historical development 

To put the current market situation into context, the historical development of wireless 
charging standards is shortly summarised in the following. In the early 2010s, three 
industry alliances developed with the goal of providing specifications for wireless power 
transfer: 

•  Wireless Power Consortium: WPC’s Qi standard was introduced in 2010. Its 
improved  version  of  2010  was  supported  by  Nokia  and  quickly  adopted  by 
further  companies  including  Toyota,  LG,  Samsung,  Philips,  Sony,  Microsoft, 
Apple  and  Huawei.  As  a  collaborative  group  with  several  hundred  members 
(Van  Mulders  et  al.,  2022),  Qi  became  the  leading  technology  for  inductive 
power  transfer  and  has  been  widely  adopted  across  various  manufacturers, 
presently being a prevalent standard for mobile phones (see chapter 4). (Detka 
& Górecki, 2022).  

•  Power  Matters  Alliance  (PMA):  Initiated  in  2012,  the  alliance  focuses  on 
creating wireless charging standards for mobile phones and electronic devices 
that  meet  the  IEEE  Society's  standards.  Initial  members  were  Powermat 
Technologies,  Proctor  &  Gamble  /  Duracell  and  several  companies  including 
AT&T,  Google,  Starbucks,  Samsung  Electronics  and  Toshiba  Corporation, 
showing its industry backing and influence (Detka & Górecki, 2022; IEEE, 2012). 
The  PMA  operated  with  inductive  charging  on  a  frequency  range  of  100-200 
kHz, typically delivering a 5 W charge over short distances (invisQi, 2021). In 
2012, it merged with A4WP to form the AirFuel Alliance. 

•  Alliance for Wireless Power (A4WP): The A4WP was formed in 2012 with the 
aim of developing frameworks for near-field magnetic resonance. Its standard 
involved 6.78 GHz frequency and Bluetooth technologies capable of charging 
without  any  manual  pairing  by  the  user.  (Tseng  et  al.,  2013).  Companies 
supporting  A4WP  specifications  include  Samsung,  Intel  and  Qualcomm 
(Shankland,  2013).  In  2012,  A4WP  merged  with  PMA  to  form  the  AirFuel 
Alliance. 

23 https://energysquare.co/powerbycontact/clientproducts/, 

https://www.lenovo.com/ao/en/accessories/lenovo-go/wireless-charging-
kit?orgRef=https%253A%252F%252Fwww.google.com%252F, downloaded February 21, 2024 

64 

 
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The competitive context of the different standards aiming for greater market presence 
was  titled  as  “charger  wars”  by  the  media,  highlighting  competition  between  the 
standards, though it soon showed that Qi and PMA had highest potential for further 
development (GSMArena, 2018; invisQi, 2021; Triggs, 2013). 

In 2015, a shift occurred when PMA and A4WP merged to form the AirFuel Alliance, 
helping to streamline the wireless charging market. (Van Mulders et al., 2022). Despite 
this, the Qi standard has continued to dominate (invisQi, 2021). 

Future developments 

As highlighted by the Predecessor Study, in 2021, the wireless charging market mainly 
standardised  around  Qi  and  some  proprietary  solutions  by  manufacturers  on  the 
consumer  electronics  market,  with  marginal  presence  of  other  standards  like  the 
AirFuel Alliance and the NFC specification.  

However, recent developments show further market consolidation regarding inductive 
charging  methods,  with  the  magnetic  attachment  technology  of  Apple’s  proprietary 
MagSafe standard being adapted into the new Qi2 version, enabling the Qi standard 
with more proper alignment and efficiency features. The new standard is available for 
certification since 2023, with first products appearing at the end of 2023 and over 100 
devices testing or in queue (WPC, 2023).  

Further, the NFC Forum positions its wireless charging specification as complementary 
to Qi (NFC Forum, 2024), which shows a potential for increasing integration of different 
technologies.  

On the other hand, there has been further development in the RF charging domain as 
well, with AirFuel Alliance announcing the launch of a certification procedure for its RF 
standard  in  January  2024  (AirFuel  Alliance,  2024).  This  enables  manufacturers  to 
practically  adopt  the  standard,  which  has  before  been  present  only  as  specification 
without  a  certification  program.  The  recent  release  of  the  program  could  leverage 
expectations for shifts in the market share of wireless charging standards, but needs 
further time to observe actual progress.  

As often highlighted by the AirFuel Alliance in various blogposts and podcasts, RF far-
field wireless charging has its most relevant use cases in industrial, public, and desktop 
ecosystem  applications  (Carman,  2023).  Therefore,  recent  developments  project  a 
future  coexistence  of  different  standards  according  to  their  target  market,  with  RF 
based  standards  emerging  in  industrial  and  low  power  use  cases  and  Qi  being 
prevalent  for  higher  power  levels  and  consumer  electronics,  especially  for  smart 
phones.  Low  power  consumer  electronics,  like  earbuds,  fitness  trackers  and 
smartwatches remain a “grey zone” in this respect, facing limitations in adopting the Qi 
standard  due  to  their  small  size  and  special  form  factor,  but  yet  not  adopting  other 
standards like resonant or RF and rather using proprietary solutions.  

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Study on wireless charging technologies 

4. 

Market overview 

4.1. 

Regulatory background 

The  European  Union  has  steadily  put  effort  for  harmonisation  of  Member  States’ 
regulations concerning the charging of radio equipment in the context of the “Common 
Charger” initiative. In 2009, a memorandum of understanding (MoU) was signed by 
major producers of mobile phones, agreeing on harmonising chargers for data-enabled 
mobile phones sold in the EU (EC, 2009). After this MoU expired in 2014, an impact 
assessment study was launched in 2018 assessing possibilities of a common solution 
for charging mobile phones (and possibly other similar categories or classes of radio 
equipment) with the following conclusions (EC, 2014):  

-  Harmonising  the  charging  interface  (receptacle)  only  would  not  result  in  full 

interoperability. 

-  Having  a  common  charging  device  across  different  types  of  radio  equipment 

would be likely to increase consumer convenience overall.  

-  Regarding  wireless  charging  (i.e.  more  generally,  charging  technology  other 
than wired charging), any breakthroughs in wireless charging technology could 
undermine  the  rationale  for  a  common  connector  solution,  by  significantly 
reducing the relevance of wired charging solutions in general. 

While  originally  aiming  at  enhanced  user  convenience,  a  reduced  amount  of 
unnecessary  electronic  waste  would  be  also  achievable 
through  enhanced 
interoperability  of  charging  devices,  urging  the  development  of  a  common  charger 
directive (EU, 2014, (12)). A  further study on unbundling mobile phones and similar 
portable electronic devices found that the separation of chargers from mobile devices 
presents distinct trade-offs, offering environmental benefits alongside financial burdens 
and decreased user convenience. The decision to weigh these environmental gains 
against the associated costs is subject to political deliberation, although the timing for 
enforcing  mandatory  unbundling  warrants  consideration,  especially  as  a  notable 
portion  of  the  industry  is  voluntarily  transitioning  towards  this  practice,  potentially 
sparking customer dissatisfaction. (EC, 2021a). Following this, a Proposal has been 
made in 2022 for amending directive 2014/53/EU relating to the making available on 
the market of radio equipment (EC, 2021b). The proposal is linked to the Commission's 
Circular  Economy  Action  Plan,  aiming  to  impact  the  entire  product  life  cycle  by 
addressing design, promoting circular economy processes, encouraging sustainable 
consumption, and retaining resources within the EU economy. Following the proposal, 
the Radio Equipment Directive 2014/53/EU was amended by Directive (EU) 2022/2380 
entered into force on 28 December 2022, and was later amended by a Commission 
Delegated Regulation (EU) 2023/1717 on 11 September 2023. 

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Radio equipment design is governed by Directive 2014/53/EU (amended by Directive 
(EU)  2022/2380),  while  the  EPS's  characteristics  are  regulated  by  Directive 
2009/125/EC  for  ecodesign  requirements  (EU,  2009),  pursued  by  the  Ecodesign 
Regulation for External Power Supplies (Commission Regulation (EU) 2019/1782 of 1 
October  2019,  pursuant  to  Directive  2009/125/EC).  Currently,  there  is  an  ongoing 
review of the latter regulation conducted by the Directorate General for Energy of the 
European  Commission  (DG  ENER)  concerning  Ecodesign  and  Energy  Labelling 
regarding  electronic  products  like  displays  and  external  power  supplies  (EPS), 
focusing  on  energy  efficiency  and  interoperability  requirements,  with  an  envisioned 
publication in 2024.  

4.2. 

Market size overview 

This section offers a thorough overview of the wireless charging market, starting with 
current  market  size  estimations  in  value  and  shipping  units,  drawing  insights  from 
multiple forecasts for future trends. A critical aspect of the wireless charging market 
lies in its  diverse  applications across  various sectors. This  section explores  product 
categories  sizes,  including  consumer  electronics,  industrial  applications,  healthcare 
devices,  defense  applications,  and  more.  The  market's  key  components,  including 
transmitters and devices like smartphones, tablets, earbuds, and smartwatches, are 
explored, with an emphasis on their current prominence and future growth potential. 
The chapter concludes by examining crucial factors affecting market growth, such as 
customer  barriers,  evolving  use  cases,  and  emerging  applications,  laying  the 
groundwork for a comprehensive understanding of the wireless charging landscape. 

Notably, most estimations refer to the wireless charging market as a whole, embracing 
several use cases. As described in the previous sections, applicable technologies can 
significantly  vary  with  different  use  cases,  especially  concerning  aspects  of  power 
levels and distance range. Findings from the literature review suggest that while Qi is 
prevalent  on  the  smartphone  market,  it  faces  limitations  with  other  appliances 
especially in the low power sector, as it requires a flat surface for highest efficiency 
levels. For standardisation considerations, it is therefore crucial to take a closer look 
on  market  expectations  concerning  the  single  applications  defined  in  the  Product 
database. Other fields where wireless charging technology gains popularity are also 
mentioned for reference, like industrial, medical and mobility applications, while these 
are not part of the present Study’s scope. 

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4.2.1.  Market size estimations 

Figure 5 – Size of wireless charging market worldwide from 2020 to 2030 

Source: Next Move Strategy Consulting, Statista, 2022. 

The global wireless charging market, as reported by Next Move Strategy Consulting 
(Figure 4), exhibited remarkable growth, reaching a valuation of 17.5 billion U.S. 
dollars in 2021 worldwide. Projections for the future are even more impressive, with 
forecasts suggesting that by 2030, the market is expected to grow to 185.9 billion 
U.S.  dollars.  The  intermediate  milestones  along  this  trajectory  indicate  substantial 
growth in the years to come, with an estimated value of 40.4 billion U.S. dollars in 2024 
and  a  leap  to  87.2  billion  U.S.  dollars  by  2027.  These  projections  reflect  a  robust 
Compound Annual Growth Rate (CAGR) of 25.7%, underscoring the accelerating 
pace of adoption and demand for wireless charging technologies on a global scale. 

Several research companies have attempted to estimate the size and growth of the 
market, and their main results are detailed in Table 7. 

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Table 7 – Global wireless charging market size estimations 

Overview of key findings from various researches 

Research institution 

Publication year 

Estimation period 

Projected CAGR 

Allied Market Research 

Transparency Market Research 

Next Move Strategy Consulting 

Grand View Research 

Market Research Future 

Fortune Business Insights 

Strategic Market Research 

Global Market Insights 

Markets and markets 

Globe Newswire 

2020 

2021 

2022 

2022 

2022 

2022 

2022 

2022 

2023 

2023 

2020-2027 

2022-2031 

2022-2030 

2023-2030 

2023-2032 

2023-2030 

2021-2030 

2023-2030 

2024-2029 

2023-2032 

22.2% 

31.9% 

29.7% 

24.2% 

22.2% 

25.8% 

22.7% 

25% 

20.3% 

24.2% 

Source: KPMG, 2024, compilation based on the above mentioned studies 

The  present  analysis  stems  from  the  aggregation  of  the  key  takeaways  from  the 
diverse  studies  conducted  by  those  research  companies  between  2020  and  2023, 
each analysing the wireless charging market to provide a spectrum of estimates and 
predictions that extend from 2020 to 2032. The goal was to analyse and find common 
trends despite variations in the studies' methods.  

Despite differences in methodology, the studies consistently show a similar CAGR. 
The  CAGRs  in  these  studies  range  from  20.3%  to  31.9%,  with  an  average  of 
24.82%  and  a  standard  deviation  of  3.856.  A  shared  conclusion  emerges  -  an 
expectation of substantial growth in the wireless charging market in the coming years. 
The average annual growth rate predicted by these studies hovers between 20.96% 
and  28.68%,  indicating  a  consensus  on  positive  market  trends.  The  previously 
mentioned 25.7% (Next Move Strategy Consulting, 2022) falls into this range. 

In  terms  of  unit  shipments,  as  indicated  by  the  Wired &  Wireless  Technologies  and 
Power  Electronics  News,  the  global  landscape  for  wireless  charging  receivers  and 
transmitters shows a substantial growth in unit shipments over the next decade. The 
forecast predicts a remarkable escalation from 725 million units in 2020 to 4.7 
billion units by 2030 (Figure 5). This anticipated growth underscores a remarkable 
uptick in the adoption and deployment of wireless charging technologies worldwide. 

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Study on wireless charging technologies 

Figure 6 – Wireless charging transmitter and receiver unit shipments  
worldwide in 2020, 2025 and 2030 

Source: Wired & Wireless Technologies and Power Electronics News, Statista, 2020 

4.2.2.  Sector size estimations 

In  order  to  provide  a  comprehensive  overview  of  the  wireless  charging  market,  it  is 
crucial to analyse the sizes of its various product categories and their interrelation. The 
sector size estimation analysis combines data from two different sources of literature, 
answering  the  same  research  questions,  but  covering  different  periods  (one  was 
conducted  between  2012-2015  with  projections  until  2022,  while  the  other  one  was 
conducted in 2020). Although, these two data set originate from different sources and 
may have been conducted using potentially different methodologies, valuable insights 
could be derived regarding to the size of the categories.  

The  Predecessor  Study  projected  market  growth  until  2022  (Grand  View  Research; 
Statista  estimates).  The  consumer  electronics  were  found  to  be  emerging  as  the 
largest  and  fastest-growing  sector,  covering  a  substantial  60% of  the  entire market. 
Following closely was the industrial segment, comprising 22.4%, and the automotive 
sector with 9.6%. 

According to Allied Market Research’s 2020 study, consumer electronics continued 
its  reign  as  the  dominant  product  category,  exhibiting  remarkable  growth 
potential with nearly a six-fold increase projected from 2018 to 2027. Similarly, 
the Predecessor Study also highlights consumer electronics as a substantial portion of 
the  market.  Both  studies  state  that  the  consumer  electronics  are  by  far  the  most 
dominant in the market, underscoring the importance of this sector. The dominance of 
consumer electronics in the wireless charging market was also underlined during the 
interviews by experts. 

A noteworthy development surfaced in the healthcare sector, which emerged as a 
formidable contender, projecting substantial growth and securing the position 
as  the  second-largest  market  sector  according  to  Allied  Market  Research.  This 
emergence  of  healthcare  was  not  explicitly  analysed  in  the  Predecessor  Study, 
signifying a notable shift in focus and relevance over the years. Although consumer 

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electronics still maintains a remarkable lead in absolute size, the healthcare sector's 
growth  trajectory  highlights  its  rising  importance.  Nevertheless,  this  depiction  is 
nuanced  by  insights  gleaned  from  the  interviews,  which  revealed  minimal  growth 
prospects in this sector at least with regards to Qi. Consequently, it may be inferred 
that alternative solutions could emerge as predominant within this sector. 

Meanwhile,  the  automotive  and  industrial  sectors,  although  slightly  trailing 
behind  consumer  electronics  and  healthcare,  are  anticipated  to  experience 
substantial growth, underscoring the evolving landscape of wireless charging across 
various industries. On the other hand, interviews conducted for this analysis revealed 
some  discrepancies,  particularly  in  the  size  of  the  industrial  sector.  These  inputs 
suggested  potential  variations  in  the  projected  growth  and  market  share  of  the 
industrial sector compared to earlier studies. 

While industrial, medical and automotive industries are not part of the study’s scope, a 
notable growth in these sectors may influence the spread of certain wireless charging 
technologies,  especially  RF  wireless  charging  which  is  found  to  be  most  suitable  in 
industrial IoT and medical applications, while electric vehicle charging relies widely on 
resonant inductive and capacitive charging (see section 3.2.2). Therefore, it cannot be 
excluded  that  while  inductive  technologies  like  Qi  are  presently  most  widespread, 
future development might show a trend of coexistence of inductive and other wireless 
charging  methods  like  RF,  whether  divided  by  sectors  or  by  use  case  (see  section 
3.2.4). 

4.2.3.  Key factors affecting market growth 

Wireless  charging  provides  consumers  with  convenience  –  or  at  least  with  the 
perception of it – eliminating the need to plug cables for charging mobile devices. It 
allows  for  effortless  device  charging  by  simply  placing  them  on  a  charging  pad, 
reducing wear and tear on physical charging ports. The technology allows integration 
into public spaces, vehicles, and furniture, making it also accessible while traveling or 
at  home.  Wireless  charging  standards,  like  Qi,  ensure  compatibility  across 
devices,  allowing  consumers  to  reuse  chargers  with  new  devices,  contributing  to 
environmental sustainability (Infineon, 2023). 

However, most  consumers  lack  deep knowledge about  wireless  charging standards 
and  technical  aspects.  Consumer  considerations  typically  revolve  around  basic 
compatibility rather than technical details. Therefore, the launch of wireless chargers 
to the market and putting them into operation requires serious consumer education. 
While  wired  chargers  are  easy  to  use,  it  is  difficult  to  explain  that  if  the  coils  of  the 
device (receiver) and the coils of the charger (transmitter) are not sufficiently aligned 
and do not overlap with each other, the charging efficiency decreases. On the other 
hand,  consumers  face  several  trade-offs  for  the  convenience  of  wireless  charging 
technology. First, wireless charging is often slower than wired charging, making it 
less time-efficient for recharging devices. Second, wireless chargers currently tend 
to be more expensive than their wired counterparts, representing a higher initial 

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financial  investment.  (Gelling,  2023.)  Third,  some  wireless  chargers  might  not  have 
been  tested  as  rigorously  as  well-known  brands  or  products  which  gain  the  Qi 
certification,  posing  potential  risks  and  difficulties  in  exercising  consumer  rights  if 
issues arise. Additionally, as mentioned above, wireless charging uses more energy 
than  wired  charging,  resulting  in  energy  loss  as  heat  and  therefore  longer 
charging times. Another drawback is limited spatial freedom, as users cannot freely 
use  their  devices  while  they  are  charging  with  inductive  technologies  due  to  tight 
coupling.  Lastly,  as  this  technology  advances,  consumers  may  need  to  consider 
whether  wireless  chargers  on  the  market  today  will  remain  compatible  with  newer 
devices and standards in the future. 

As  wireless  charging  technology  is  still  developing,  use  cases  are  evolving  and 
customer  needs  are  not  perfectly  met  yet.  Further  innovative  effort  seems  to  be 
required in this field to maintain customers’ attention to wireless charging. 

User  convenience  aspects  mentioned  in  expert  interviews  and  in  relevant 
literatiure of wireless charging are the following, with a closer look to two differing 
technologies:  the  most  widespread  inductive  (Qi)  method  and  a  possible  emerging 
technology, RF charging. 

•  Efficiency, charging speed and labelling: For detailed figures, see chapter 
6.1. Inductive charging can be very efficient over short distances, with power 
conversion efficiency being one of its major benefits when devices are correctly 
aligned.  This  enables  standards  like  Qi  to  be  among  the  most  popular  for 
consumer  electronics,  delivering  a  lower  but  still  acceptable  charging  speed 
compared to fast wired charging. Typical use cases can be charging the device 
over night, when not in use. On the other hand, the need for precise alignment 
and  the  potential  for  interference  can  reduce  overall  efficiency,  which  may 
influence user experience and lead to frustration. The introduction of magnetic 
alignment  (like  the  MagSafe  technology)  attempts  to  address  this  issue, 
providing more convenient and accurate alignment. The Qi2 standard, which 
is  partially  based  on  MagSafe  technology,  facilitates  precise  alignment 
thanks to the magnetic attachment. But consumers may perceive magnets 
used in Qi2 for alignment as not truly wireless, desiring more seamless 
solutions. Charging power below 15 W does not meet consumer needs, thus 
some manufacturers have designed their own products and are seeking other 
solutions  to  increase  power  transmission  in  order  fulfil  their  customers' 
expectations. On the other hand, some expert opinions reflect that customers 
are  not  primariliy  seeking  higher  power  but  faster  charging  speed,  and 
nominally higher power levels still do not remarkably raise speed levels 
due to energy and efficiency losses. Also, studies conducted in this matter 
show that it is basically not possible to label any inductive charger by its energy 
efficiency, as it strongly depends on the paired device. A study on Qi wireless 
charging efficiency found it to be impossible to define a representative efficiency 
test  for  inductive  technologies  interoperating  with  more  than  one  receiver 
design. (Perzow, 2022.) Therefore, consumers need proper knowledge of the 

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frustration.  Regarding  RF  charging, 

technology, requiring consumer education in order to enable informed purchase 
decisions,  preventing  user 
the 
technology  generally  has  a  very  low  efficiency  of  power  transmission, 
leading to energy loss compared to other charging methods. The efficiency 
may  also  decrease  with  the  range,  increasing  the  distance  might  lead  to  a 
decrease in efficiency. (Detka &Górecki, 2022; Nnamdi &Asianuba, 2023.) From 
users’  perspective,  charging  up  a  phone  by  RF  charging  would  just  take  too 
much  time  and  is  therefore  not  a  viable  option  in  daily  operations.  Users  are 
usually not aware of the fact that the charging speed, power transmission and 
energy efficiency are influenced by many other factors, the most important being 
the appropiate combination of transmitter and device (receiver). The first thing 
users are interested in at retail is the charging speed (power transmission), but 
they  are  rarely  told  that  the  this  charging  speed  is  nominal  and  can  only  be 
achieved  with  proper  compatibility.  On  the  other  hand,  manufacturers  and 
alliances  themselves  cannot  provide  accurate  information  regarding  charging 
speed  and  energy  efficiency,  since  the  same  charging  conditions  (ceteris 
paribus) cannot be reproduced in everyday use.  
As an example, there are a number of problems when testing devices for the Qi 
standard, with many factors that are important such as, the position and size of 
the coils as well as the size of the transmitter and receiver. If there are small 
and big coils involved as part of the charging transmission, the combination of 
different sizes can cause major differences in performance. These factors can 
lead to completely different results on the exact same device. This is the reason 
why the unified measurement of energy efficiency is not yet solved.  

•  Ease  of  Use:  Users  do  not  need  to  plug/unplug  cables,  which  provides  a 
seamless  experience.  With  inductive  charging,  simply  placing  a  device  on  a 
wireless  charging  pad  initiates  the  charging  process,  where  the  charger  can 
become a natural part of the environment (e.g. furniture integration). Use cases 
with good potential for user convenience are therefore surfaces like desks 
or nightstands, where users usually keep their devices for a longer time, 
or situations where plugging in a cable is difficult, e.g. while driving a car. 
Wireless  charging  gains  an  edge  in  automotive  settings  due  to  the  ease  of 
picking up and putting down the phone while driving, unlike traditional cables 
that  require  unplugging  and  replugging  which  comes  with  safety  concerns  in 
congested traffic situations. Automotive brands cannot afford to fall behind their 
competitors in wireless charging as an innovation, this statement is especially 
true for the e-cars. One of the major barriers to Qi wireless charging is the 
requirement  of  a  flat  surface  on  which  the  charger  is  placed.  Perfect 
alignment  can  rarely  be  met  in  everyday  life,  which  can  be  frustrating  when 
users are facing the fact during rush hours in the morning that despite having 
left their phones on the charging pad over night, the phone has not yet been 
charged in the morning due to alignment issues. Magnetic attachment as seen 
with the Qi2 standard or MagSafe do mitigate this problem. A recurring aspect 
in  expert  interviews  was  Qi  charging  not  being  truly  wireless,  as  it  is  still 
connected  to  the  EPS  via  cables  and  initiates  charging  only  on  a  very  short 

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distance to the device. The trade-off is not attractive enough in terms of user 
comfort: a wireless charger still needs a 230V socket and only the contact to the 
device itself is wireless. There is little convenience gain by placing a device on 
an induction pad compared to plugging an USB plug in. RF charging methods 
promise to be a lot easier to use, as once the transmitter device is installed, no 
interaction is required by the user and charging happens even on a distance of 
several meters, similarly to signals of a WiFi router. This is especially useful in 
environments where manual connection to the charging source is challenging, 
e.g. for medical devices implanted in the human body. The real target group for 
wireless charging technology is formed by users living in cities, where they have 
more opportunities to meet charging stations and need less energy to get to the 
next  place where  they  can charge their  phones.  Conversely, users  in remote 
locations  will  need  to  fully  charge  their  battery  fast,  as  the  next  charging 
opportunity  may  be  further  away.  Overall,  it  is  worth  highlighting  customers 
increased spatial freedom, ability to charge multiple devices at the same time 
and independent of the devices’ different power requirements. 

•  Device longevity: The absence of physical connectors means less mechanical 
wear and the potential for damage to charging ports, being the most vulnerable 
element  of  consumer  electronics  devices.  Devices  that  support  wireless 
charging can be more rugged and waterproof, as they don’t need open ports 
that could compromise their integrity. The use of wireless charging can be thus 
increase  the  lifespan  of  devices.  This  pertains  both  to  inductive  and  RF 
charging.  However,  possible  heat  generation  using  inductive  charging 
methods might affect battery health over time. Concerning RF charging, no 
similar  disadvantages  to  device  lifespan  are  reported  for  the  time  being, 
although,  due  to  lack  of  proper  knowledge  customers  might  experience 
changes, but do not able to recognise the rootcauses.  

•  Cable  management:  While  inductive  charging  reduces  cable  clutter  and 
eliminates the need for different types of cables for different devices, RF 
technology allegedly does eliminate the need for cables at all. This cannot be 
stated  for  inductive  methods,  as  they  still  require  the  charging  pad  to  be 
connected to a power source. Therefore, inductive technology like Qi still implies 
a  smaller  amount  of  cables,  which  need  to  be  managed  or  can  be  tangling, 
reducing the user comfort and design perceptions. Thus, it cannot be said to be 
completely free of cables. However, due to education deficit, average customer 
is not able to distinguish between technologies from this aspect. 

•  Compatibility:  Several  experts  are  hearing  echoes  of  compatibility  issues 
between  older  and  newer  versions  of  wireless  charging  pads  and  devices. 
Customers  generally  worry  that  newer  models  may  not  be  backwards 
compatible,  causing  confusion  and 
the  ecosystem. 
Standardisation  with  Qi  promotes  interoperability,  allowing  various 
devices to use the same charging pad, regardless of the manufacturer. It 
further  allows  compatibility  across  different  devices.  While  mainly  being 
supported  by  mobile  phones,  Qi  theoretically  has  the  potential  to  be 

fragmenting 

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implemented in any consumer electronics device with a flat surface of a 
reasonable size. The Qi certification implies interoperability tests and backward 
compatibility, which enhance user convenience. However, the receiver needs 
to be embedded into the device, which is currently mainly supported by high-
end and flagship smartphone models. Therefore, compatibility is limited to a few 
product models for the time being. Add-on receivers could mitigate this issue, 
allowing the consumer to adapt the technology even if it is not implemented yet 
by device manufacturers. Regarding RF charging, standards are still developing 
and currently, a supply chain ecosystem similar to that of the Qi standard can 
not  be  identified  on  the  market.  Therefore,  pioneer  users  of  the  first  models 
appearing on the B2C market may face compatibility issues. For more details 
on interoperability and compatibility, see chapter 6.1. 

•  Charging distance, spatial freedom and mobility: While wireless charging in 
general  does  support  a  greater  mobility  than  wired  charging,  differences 
can  be  observed  between  technologies.  Inductive  charging  pads  can  be 
placed  where  convenient  but  need  an  EPS  nearby.  Though  newer 
technologies allow some spatial freedom, currently, there's limited range 
and  devices must  stay  close to  the  charging pad. An  in-between  solution 
could be the use of wireless charging capable power banks, which can be freely 
carried and thus ensure a greater mobility. RF charging methods on the other 
hand are capable of charging over larger distances of several meters, but with 
the  charging  power  decreasing  with  increasing  distance.  Also,  no  records  of 
integration  into  power  banks  have  been  found,  so  it  is  assumed  that  the  RF 
antenna is a fixed position transmitter, thus limiting mobility. On the other hand, 
RF technology does not require close contact or alignment, some being capable 
of charging moving objects and therefore allow for some spatial freedom and 
movement  within  the  charging  range  of  the  transmitter.  RF  charging 
theoretically  would  have  the  possibility  to  cover  even  larger  distances,  but 
practically,  health  issues  and  interferences  caused  by  the  higher  frequency 
pose  severe  limitations  on  this.  Customer  experience  remains  a  barrier  to 
market growth due to perfect alignment requirements for inductive charging and 
inefficiencies in far-distance charging. 

•  Multi-Device Charging: The greatest level of convenience and waste reduction 
is achieved by transmitters capable of simultaneously charging multiple devices. 
Qi charging pads tend to be capable of charging only one device at once, while 
RF antennas do not have limitations in this regard. On the other hand, there are 
certain inductive charging pad models supporting simultaneous charging 
of  different  types  of  devices,  e.g.  3  in  1  charger  solutions.  But  inductive 
means of charging imply that this is only possible by increasing the size, quality 
or number of embedded coils. This makes multiple device inductive chargers 
more  expensive  and  imposes  limitations.  An  ultimate  solution  for  user 
convenience  may  be  a  wireless  power  system  at  home,  constantly 
powering multiple devices. On the one hand, this is quite expensive, and the 
power  level  is  very  low  but  constant.  A  good  solution  might  be  the  emerging 

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technique of energy harvesting, where devices harness small amounts of power 
from existing signals (e.g., WiFi) without the need of adding new technology. 

•  Green (ecological) and sustainability aspects: Although ecological benefits 
do not belong to the strongest user considerations, the first signs of efforts to 
reduce the amount of electronic waste can already be detected, although rather 
to avoid unnecessary lumber than for environmental protection reasons. On the 
side of manufacturers, some experts perceive growing interest in sustainability 
efforts.  Wireless  charging  could  contribute  to  making  products  more 
sustainable  by  prolonging  the  life  expectance  of  cables  and  devices. 
However,  the  sustainability  requirements  for  inductive  charging  technologies 
can  only  be  met  if  full  interoperability,  cross-brand  compatibility,  backward 
compatibility  and  multi-device  charging  are  truly  achieved,  as  these  features 
lead to reduction of the charging equipment. On the contrary, convenience and 
cost are the two most important decision factors. Some experts highlighted that 
this depends mainly on whether the European Commission aims to encourage 
consumers to use green charging solution. 

•  Design and Aesthetics: Wireless chargers can be designed to blend in with 
the  environment  or  add  a  touch  of  style,  in  contrast  to  the  utilitarian  look  of 
traditional  chargers  and  cables.  Some  scenarios,  such  as  smart  mugs  or 
furniture  with  integrated  wireless  charging,  encourage  natural  placement  of 
devices  on  charging  surfaces,  effectively  hiding  the  technology  and  making 
charging  a  more  intuitive  and  integrated  part  of  daily  life.  Implementations  of 
aesthetic embedment of Qi chargers in furniture and cars already can be seen 
on the market. The size of the charging pad may take up space and design still 
needs to be developed to match decor, but there are already promising solutions 
like  lamps  and  ambience  decoration  stands  available  for  purchasing.  The 
charging pad of wireless charging systems can no longer just be a device, but 
needs also to be an aesthetic, furnishing item, that is part of the interior design, 
believed  by  some  engineers.  Form  factor  requirements  of  inductive  methods 
influence the compatibility of devices by design and can be perceived as “bulky” 
and less practical by consumers. There is currently no discussion in this subject 
concerning RF charging methods, as implementations on the market are quite 
rare and usually only available for industrial use. As antennas can be small, RF 
means of wireless charging should impose no limitations to shape and size of 
devices and provide a freedom of design. Still, most observable furniture with 
integrated charging function uses inductive charging. However, several experts 
believe that furniture manufacturers are less motivated to incorporate wireless 
technologies  into  their  furniture,  explainable  by  the  simultaneous  lack  of 
expertise and intention, as well as by the fact that furniture manufacturers do 
not want to take the risk of a reputational deficit due to a faulty charging pad. 
The  troubleshooting  process  caused  by  the  defect  of  charging  pads  requires 
new  business  flows  and  tight  cooperation  with  IT  manufacturers,  as  well  as 
allocated human resources to this tasks. 

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•  Safety: Wireless charging can reduce the risk of electrical faults or short circuits 
that may occur with damaged cables or connectors. Inductive technologies like 
Qi reduce risk of electric shock since the contacts are not exposed, as well as 
secure authentication in newer systems. Older versions or inductive methods 
apart from Qi may not have this communication protocol enabling the charging 
pad of foreign object detection, which might lead to overheating metal objects 
accidentally  put  on  the  charging  surface  (e.g.  keys  or  coins).  According  to 
experts,  there  are  clear  user  concerns  about  foreign  object  detection  and 
security issues. As far as they know, the current standardisation process checks 
for these issues during compliance testing to prevent potential safety hazards, 
especially  for  metal  foreign  objects  that  heat  up  during  charging.  There  have 
been  reported  issues  of  damage  in  phones  or  their  accessories  caused  by 
inductive chargers.  For  RF  charging,  currently no such issues  are known but 
are likely to occur in the high-power range. As these frequencies are limited by 
regulation, no risk is to be expected of legally compliant RF charging methods.  

•  Health:  Wireless  charging  can  be  struggling  with  biased  consumer 
perceptions  due  to  the  application  of  electromagnetic  fields.  Actually, 
inductive charging methods are generally believed to be safe as no harm 
has been reported due to long-term exposure. RF charging on the other 
hand comes with health risks in higher frequency bands when radiation 
gets in contact with human tissue. The current mitigation lies in limiting the 
frequency band in 6.78 GHz, which reduces convenience because of the small 
amount of power which is broadcasted at this frequency. A future solution could 
be  the  retrodirective  technology  already  implemented  by  Ossia  in  their  Cota 
standard. Using a transmitter system with beacon signals determining the paths, 
the  system  does  not  emit  signals  through  any  blocked  path,  meaning  the 
radiation  basically  goes  around  people  and  other  obstacles  identified  as 
blocking.  Ossia  defines  the  technology  as  “gamechanger”  for  RF  wireless 
charging, overcoming its greatest convenience issue which might be a reason 
why the technology has not been widely implemented in consumer fields at the 
time being. Further evolvement of this technology needs to be observed as it is 
currently not available on the consumer market and therefore cannot be backed 
by  actual  customer  reviews.  However,  as  wireless  power  transfer  technology 
evolves, continuous research and monitoring are essential to ensure it remains 
safe for users and the environment. Safety concerns regarding RF technologies 
interaction  with  living  organisms,  human  body  and  existing  electronics  are 
currently restraining market adaptation to applications that require less than 1 
Watt of power. 

•  Cyber  security:  Being  a  hot  topic  of  the  last  years,  Cyber  Security  aspects 
might  have  an  influence  on  customer  perception  of  wireless  charging 
technologies or even cause anxiety or reluctance to use it. No record has been 
found  of  any  incident  to  have  occurred  neither  with  inductive  nor  RF 
charging, while scientific research presented evidence for the possibility 
of hacking and stealing data through inductive chargers, especially those 
installed in public places like railway stations or airport lounges (Liu et al., 

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2021). Should any incident occur and get viral in the media, this would mean a 
serious  reputational  damage  for  wireless  charging  technologies.  Therefore, 
special attention is granted to this aspect by manufacturers and developers, a 
majority  of  them  experiencing  no  greater  cyber  security  issue  than  with  any 
other wireless solution (e.g. WiFi), or even less as wireless chargers usually are 
not connected to the internet. 

•  Availability: Inductive charging systems are becoming increasingly available in 
various industries (see chapter 4.2.) The widespread adoption depends on the 
standardisation  of  technologies  like  the  Qi  standard  to  ensure  compatibility 
across  different  devices  and  chargers.  Efforts  can  be  witnessed  from 
industry alliances like the WPC to promote interoperability, thus building 
and  strengthening  an  ecosystem  with  suppliers  and  retailers  along  the 
supply chain. Other technologies like RF charging are still developing and still 
lacking notable presence on the consumer market. Although some experts are 
optimistic  about  the  supply  chain  of  new  technologies  and  believe  that  the 
supplier,  vendor,  manufacturer  and  distribution  side  will  develop  nicely,  other 
experts  have  doubts  about  the  stability  of  the  ecosystem.  It  is  not  taken  for 
granted  that  all  players  in  the  ecosystem  will  find  appealing  promise  in  this 
industry. There is a butterfly effect: if existing players in the ecosystem strive to 
build  a  smooth  functioning  supply  chain  and  alliances  develop  an  unbiased 
standardisation  and  compliance 
the  market  can  welcome 
tests, 
newcomers to an extending industry sector. Otherwise, there is a risk that stable 
and reputable market players will stay away from this market. 

then 

• 

that  support 

Interferences: Inductive coupling typically operates at low frequencies, which 
can reduce the level of electromagnetic interference (EMI) with other devices. 
inductive  charging  have 
Modern  Qi-compliant  chargers 
authentication mechanisms to ensure reduced interference and safer operation. 
However, 
longer 
implementing  magnetic  resonance,  which  allows 
transmission distances, can be sensitive to movement and external conditions, 
affecting the  reliability  of  charging and  increasing  interference  probability.  RF 
charging  might  be  prone  to  interference  from  other  RF  sources  which  could 
affect efficiency or the charging process, as many devices and systems operate 
on radio frequencies. For user convenience, it is therefore crucial to define a 
frequency  band  which  is  not  disturbing  or  being  disturbed  by  other  devices 
commonly used by consumers.  

for 

•  Vision of community charging: Wireless charging technology allows for more 
freedom as charging may get more accessible in public and office spaces. 
Thus, the users do not need to remember carrying a cable with them or checking 
their devices’ power level before leaving home. For example, furniture with built-
in  inductive  charging  pads  or  charging  spots  in  public  spaces  provide  power 
without needing to carry a charger. Some examples already can be found e.g. 
at restaurants and coffee shops. Some experts outlined a similar idea for RF 
charging,  with  energy  being  broadcasted  by  an  infrastructure  of  public 
antennas,  enabling  countinuous  charging  while  walking  on  the  streets.  This 

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scenario would result in the highest level of user convenience, making charging 
a fully automatised, non-conscious background process. However, experts also 
explained this is a long-shot goal and currently not at all implemented due 
to regulatory and economic limitations.  

•  Saving energy, reducing the utility bill (mainly electricity): This seems to 
be  a  marginal  decision  point  from  customer  perspective,  being  hardly 
mentioned.  Despite  possible  reductions  in  electricity  bills  –  although  not  all 
experts  are  convinced  of  this  –  they  doubted  that  this  aspect  would  affect 
consumer demand. 

•  Education deficit: The launch of wireless chargers in the market and putting 
them into operation requires serious consumer education. While wired chargers 
are easy to use, it is difficult to explain that if the coils of the device and the coils 
of the charger are not sufficiently aligned and do not overlap with each other, 
the charging efficiency decreases. Many users are not aware of the fact whether 
their  phone  is  compatible  with  wireless  charging.  They  also  need  further 
education in order to develop a sophisticated system of consideration criteria, 
not just considering the charging speed. Most consumers lack deep knowledge 
about wireless charging standards and technical aspects. Overall,  consumer 
considerations typically revolve around basic compatibility and the level 
of  power  transmission  rather  than  other  technical  specification.  Most 
customers  don't  prioritise a  specific  charging standard  (as  they usually 
cannot  recall  any  of  them),  instead,  they  purchase  available  market 
solutions. 

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Table 8 – Summary of the main pain points and positive experiences 

Based on literature review and expert insights 

Category 

Pain points 

Efficiency, Charging 
Speed, and Labeling 

Ease of Use 

Inductive charging efficiency, alignment 
issues and frustration, interference, 
MagSafe, labeling challenges, RF charging 
inefficiency, alignment importance, 
compatibility challenges 

Alignment frustration, compatibility issues, 
desire for less alignment, spatial freedom, 
mobility concerns 

Positive experiences / 
opportunities 

MagSafe to improve alignment, 
convenience, potential for RF 
charging in specific use cases 

Seamless experience, RF charging 
convenience 

Device Longevity 

Heat generation, battery health 

Reduced wear, increased lifespan 

Cable Management 

Power source dependence, fixed 
transmitters 

Cable elimination 

Compatibility 

Older/newer device compatibility, Limited 
interoperability 

Widespread Qi compatibility 

Charging Distance, 
Spatial Freedom, and 
Mobility 

Limited spatial freedom, wireless power 
banks, mobility limitations, health risks, 
interference 

RF charging distance 

Multi-Device Charging 

Limited multi-device capabilities 

RF charging advantages 

Green and 
Sustainability Aspects 

Design and Aesthetics 

Safety 

Health 

Cyber Security 

Interoperability issues 

Perceived bulkiness, design limitations, 
reluctance from manufacturers 

Health risks, retrodirective technology 

Ecological benefits - electronic 
waste reduction 

Blend with environment 

Electrical fault reduction, 
authentication protocols 

Safety concerns, electromagnetic fields, RF 
health risks 

Hacking vulnerabilities, damage potential, 
user trust 

- 

- 

Availability 

Ecosystem stability concerns 

Increasing availability, RF 
technology development, 
standardisation efforts, 

Interferences 

Electromagnetic interference, magnetic 
resonance challenges, RF interference 

- 

Vision of Community 
Charging 

Regulatory and economic limitations 

Public space accessibility 

Saving Energy 

Uncertain consumer demand 

Potential electricity bill reduction 

Education Deficit 

Consumer education lacking, compatibility 
and technical understanding gaps 

- 

Source: Key factors affecting market growth (Section 4.2.3.) 

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4.3. 

Voice of the Customer 

Introduction 

In the dynamic landscape of wireless charging technology, understanding the Voice 
of the Customer (VoC) is paramount for driving innovation and meeting consumer 
needs effectively.  While  extensive literature  reviews  and  expert interviews  have 
provided valuable insights (Table 8), the sheer diversity of findings underscores 
the  complexity  of  this  domain.  These  findings  serve  as  the  foundation  for 
hypotheses regarding consumer expectations and market maturity. However, to truly 
grasp the customer perspective, a qualitative analysis becomes indispensable. 

This chapter delves into the VoC, examining the prevalent pain points and potential 
barriers  experienced  by  consumers  in  the  adoption  of  wireless  charging  solutions. 
Through detailed research and analysis, this section aims to paint a thorough picture 
of market expectations and the maturity of the market. Utilising the Product Database 
(PD) alongside Amazon's best seller listings, a diverse selection of 70 products from 
42  brands  was  curated.  Emphasising  authenticity,  real  customer  feedback  was 
gathered, particularly focusing on 1-star evaluations, culminating in the analysis of 820 
unique reviews. This thorough process ensured a comprehensive understanding of 
user experiences, encompassing both positive and critical perspectives. 

By bridging the gap between theoretical understanding and real-world consumer 
experiences, this section strives to contribute to the advancement of wireless charging 
technology. 

Results 

The findings are consistent with the literature review and expert insights, since 
the  main  negative  feedbacks  are  related  to  charging  speed,  alignment  difficulties, 
overheating, and compatibility challenges. These takeaways can be also seen in the 
wordcloud (Figure 6), where “slow”, “case”, “place”, “hot” and “compatible” are 
amongst the most commonly used words in the collected reviews (and thus written 
with  the  biggest  letters  in  the  worldcloud),  underscoring  their  significance  in  user 
perceptions and experiences. 

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Figure 7 – Wordcloud from negative customer reviews 

Source: KPMG 

Additionally,  two  customer  comments  were  cited  for  each  topic  that  properly 
summarise  the  frequently  arising  issues.  These  comments  are  perfect  to  provide  a 
“first-hand” understanding of the common issues faced by consumers, and to identify 
recurring themes and underlying patterns.  

Charging speed. Many users have noted that wireless charging is much slower than 
traditional wired charging. There were instances where the charging speed was “very 
slow” or that the charger only managed to slightly increase battery percentage over a 
long  drive  or  period.  In  some  experiences,  even  with  fast  charging  adapters,  the 
wireless charging did not speed up, taking several hours to fully charge or only partially 
charging overnight. 

• 

• 

“…this  thing  charges  significantly  slower  than  when  my  phone  is  plugged 
directly in to the wall. If I'm in a hurry, I unplug the USB connection from the 
charger and set it directly to my phone instead…” 

“…even when i do remove the case and get it to charge, its very slow. It took 
almost 3 hours to charge from 62% to full…” 

Case sensitivity and alignment issues. A number of users encountered difficulties 
charging their phones with cases on, even when those cases were relatively thin. The 
magnetic  connection  that  is  supposed  to  align  and  secure  the  phone  for  optimal 
charging was not always effective, requiring users to find the right spot or make slight 
adjustments to engage the charging process. Users frequently mention that wireless 
chargers often struggle to maintain a consistent connection. Charging may start and 
stop  intermittently,  or  the  devices  may  not  charge  unless  placed  in  a  very  specific 
position.This  increased  the  challenges  for  individuals  in  correctly  positioning  their 
phones, leading to frustration and inconvenience. 

• 

“…this does not do very well if your phone is in a case. My case is not that thick, 
yet still interferes with charging…”  

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• 

“…When I line up my phone with the  charging side panel, it will only light up 
when I place it an extremely specific way. One angle out of place and it will stop 
charging…” 

Overheating issues. Overheating is a common concern among users, with mentions 
of phones getting excessively hot during the charging process. This not only affects 
user  comfort  but  also  raises  concerns  about  potential  damage  to  the  battery  or  the 
smartphone itself. 

• 

• 

“…the  main  phone  charger  area  is  extremely  slow  (like  30%  charged  after  4 
hours) and makes my phone lava hot. It occasionally stops charging because 
of the overheating…” 

“…I'm  concerned  it  might  start  a  fire  (also  why  I  don't  recommend  it  for 
travelling), and am concerned the extreme heat of charging could damage my 
phone…” 

Compatibility issues. Even when products are listed as compatible with certain phone 
models, users report that the wireless charger does not work or has major functionality 
issues. Several customers also report receiving products that are incompatible with the 
cases they use, despite claims that they should work. 

• 

• 

“…I  was  really  disappointed  after  several  troubleshooting  to  find  out  that  my 
[earbuds] would not charge even though that generation is compatible with this 
charging device…” 

“…Despite being advertised as compatible with various devices, including […], 
its  universal  Qi  compatibility  proved  to  be  unreliable.  The  charging  pad 
frequently failed to initiate charging, rendering it essentially useless in real-life 
scenarios…” 

In  conclusion,  the  examination  of  wireless  chargers  through  real  customer 
evaluations  corroborates  the  insights  gathered  from  the  literature  review  and 
expert interviews, revealing no new dimensions beyond those previously identified. 
Among  the  factors  affecting  user  experience,  three  dimensions  stand  out 
prominently:  Efficiency,  Charging  Speed,  and  Compatibility.  The  disparity  in 
charging  speeds  compared  to  wired  counterparts  remains  an  important  concern, 
exacerbated  by  alignment  difficulties  and  overheating  issues  inherent  in  current 
wireless  charging  technologies.  Moreover,  compatibility  challenges  persist  despite 
efforts  to  standardise  wireless  charging  protocols,  indicating  a  need  for  clearer 
communication  between  manufacturers  and  greater 
in  product 
specifications. Addressing these issues will be paramount in enhancing the usability 
and  reliability  of  wireless  chargers,  ultimately  fulfilling  consumer  expectations  and 
driving broader adoption of this technology. 

transparency 

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Study on wireless charging technologies 

5. 

Product overview 

This section presents the findings related to the different product categories. For each 
product category the followings are presented: 

•  Category overview – scope of analysed product category 

•  Market data – highlights of the available market information about the category 

•  Current  situation  –  overview  and  findings  regarding  the  category  primarily 

derived from the PD  

Key outcomes from the expert interviews are highlighted in relevant sections. In cases 
where information was not available specifically on a given wireless charging product 
category, the Study highlighted market data regarding the entire market of the product 
category  (wireless  and  non-wireless)  and  attempted  to  draw  conclusions  about  the 
category  by  utilising  other  information  as  well,  such  as  the  proportion  of  wireless 
charging capable products in given product category. Additionally, the findings of the 
present  Study  (category  overview,  market  data,  current  situation  based  on  PD) 
regarding  add-on  receivers  and  other  electronic  devices  are  highlighted  within  one 
section  due  to  limited  information  available  and,  their  importance  proved  to  be  less 
relevant in the overall wireless charging market. Moreover, data collection principles 
are  not  highlighted  in  detail  within  this  chapter.  For  more  detail  regarding  to  data 
collection principles of the PD, please refer to section 2.2.  

5.1.  Wireless charging transmitters 

5.1.1.  Transmitters (standalone and embedded) 

Category overview 

This product category incorporates transmitters that are used to charge devices that 
could  be  charged  wirelessly.  Same  categorisation  has  been  used  as  in  the 
Predecessor  Study.  Within  the  product  database  the  following  categories  has  been 
used for transmitters: 

•  Standalone transmitters  

•  Embedded transmitters 

For detailed description of transmitter types, please refer to section 2.2 and 3.1 

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Study on wireless charging technologies 

Market data related to transmitters 

Examining the global consumer charging market (wired and wireless charging market 
combined)  reveals  a  landscape  characterised  by  diverse  estimates  and  projections. 
Various  research  firms  have  attempted  to  gauge  the  size  of  the  broader  charger 
market, yielding a wide range of findings. For instance, Global Newswire reported a 
figure of 21.78 billion U.S dollars in 2022 with a CAGR of 6.4% by 2030, while another 
study cited 23.36 billion U.S dollars in 2024 with a CAGR of 7.54% by 2028 (Business 
Research Insights, 2024). IMARC, on the other hand, estimated 25.8 billion U.S dollars 
in 2023 with a CAGR of 4.5% by 2032. When analysing these diverse research reports, 
it  is  important  to  note  that  they  encompass  every  aspect  of  battery  charging 
applications,  including  those  for  electric  vehicles  (EVs)  and  consumer  electronics. 
According  to  IMARC  (2023),  the  EV  market  comprises  15%  of  the  total  charging 
market, implying that the remaining 85% is attributed to other consumer electronics. 
This  insight  allows  for  an  estimation  that  the  total  consumer  electronics  battery 
charging market falls within the range of 19 to 22 billion U.S. dollars, considering the 
figures provided by various sources. 

In  the  case  of  wireless  charger  market,  expert  interviews  performed  during  the 
preparation of the present Study suggest that wireless chargers market accounts for 
approximately  20%  of  the  total  charger  market  in  revenue.  Utilising  this  insight,  the 
consumer electronics wireless charger market size can be approximated, ranging 
between 3.8 U.S billion dollars to 4.5 billion U.S dollars according to available data. 
Based on the interviews with the experts, the demand for wireless chargers and first of 
all Qi chargers is a derived demand, which results from the sales volume of mobile 
phones.  Despite  uncertainty,  forecasts  suggest  a  notable  growth  trajectory  for  the 
global  wireless  charging  transmitter  market,  with  Report  Prime  projecting  a  3.6% 
CAGR throughout the 2022-2030 forecast period.  

The global industrial wireless transmitter market is poised for substential growth, 
with projections indicating an increase from 3.2 billion U.S dollars in 2023 to 5 billion 
U.S dollars by 2029. This expansion is anticipated to occur at a CAGR of 7.7%, as 
reported  by  Market  Reports  World.  This  forecast  underscores  the  potential  for 
substantial developments in the industrial wireless transmitter sector over the forecast 
period. 

Similarly,  the  global  in-car  wireless  charging  market  is  witnessing  a  positive 
trajectory,  with  a  forecasted  CAGR  of  4.72%  between  2020  and  2027,  which 
contributes  to  the  spread  of  embedded  solutions.  In  2022,  the  market  size  reached 
approximately 1.93 billion U.S. dollars, and it is expected to reach 2.55 billion U.S. 
dollars  by  2030,  according  to  reports  from  MRFR  &  GlobeNewswire  (2023).  This 
growth signifies a shift in the automotive industry towards wireless charging solutions, 
likely  influenced  by  consumer  preferences  for  convenient  and  cable-free  charging 
options. 

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Study on wireless charging technologies 

While  the  total  wireless  charging  market  (that  includes  wireless  charging 
transmitters  as  well  as  devices  that  can  be  charged  with  wireless  charging) 
demonstrates  an  impressive  CAGR  of  25.7%  (Next  Move  Strategy  Consulting, 
2022), the wireless transmitter market forecasts a lower yet still notable CAGR 
of 3.6%. This suggests that while the overall wireless charging market is experiencing 
robust  growth,  the  transmitter  market  is  growing  at  a  slower  pace.  Based  on  the 
mentioned  CAGR  values,  it  is  concluded  that  devices  suitable  for  wireless 
charging  (e.g.  mobile  phones)  will  spread  first  and  that  these  will  lead  to  the 
expansion  of  the  charger  market.  However,  despite  the  slower  growth  in 
transmitters, the increasing adoption of wireless charging-enabled devices is likely to 
drive the demand for chargers, indicating a promising future for the charger market. 
Additionally, the wireless charging market comprises various applications and sectors 
with varying growth rates. For instance, the in-car wireless charging sector, represents 
a  subset  within  the  broader  market,  highlighting  the  diverse  dynamics  within  the 
wireless charging landscape. 

Figure 8 – Wireless charging pads sold worldwide 2023, by retail price 

Based on Amazon and Walmart prices 

Courant Catch 3 Wireless Charger

Nomad MagSafe Base Station

Nomad Base One Max

Apple - MagSafe Duo Charger

Anker PowerWave 4-in-1 Charger

Belkin 2-1 Charging Stand

Apple MagSafe Battery Pack

175

160

150

129

120

97.71

95

Mophie Snap Plus Powerstation Stand

Satechi Aluminum 2-in-1 Wireless Charging Stand

Samsung 2-in-1 Portable Fast Charge Wireless Charger

iOttie Wireless Car Charger

69.77

59.99

50

49.95

Huoto Portable Wireless Charger for Apple Watch

20.99

Anker PowerWave Wireless Charging Stand

Tozo W1 Wireless Charger

20

10.99

0

50

100
U.S. dollars

150

200

Source: Spy, 2023. 

In  the  wireless  charging  transmitter  market  as  of  March  2023,  pricing  diversity 
reflects varying features and brand distinctions (Figure 7). Spy conducted a survey 
in  the  United  States, unveiling  notable  products  at  both  ends  of  the  spectrum  (Spy, 
2023). The Courant Catch 3 Accessory Tray lead the high-end, priced at 175 U.S. 
dollars, mostly thanks to its exclusive design features. Nomad's MagSafe Base Station 
and  Base  One  Max  followed  closely,  priced  respectively  around  160  and  150  U.S. 
dollars.  On  the  lower  end,  the  Anker  PowerWave  Wireless  Charging  Stand  offered 
affordability at 20 U.S. dollars, while the Tozo W1 Wireless Charger standed out as a 

86 

 
Study on wireless charging technologies 

budget-friendly option at 10.99 U.S. dollars. These diverse pricing tiers cater to 
consumers  with  varying  preferences,  from  those  seeking  advanced  design  and 
aesthetic  solutions  to  budget-conscious  individuals  looking  for  accessible  wireless 
charging solutions. 

In summary forecasts for the growth rates of various sub-categories within the market 
is outlined. Notably, a 3.6% CAGR for consumer transmitters, 7.7% CAGR for industrial 
transmitters,  and  4.72%  CAGR  for  in-car  transmitters  is  anticipated.  However,  it's 
crucial  to  note  that  despite  these  projections,  they  won’t  reach  the  25.7%  CAGR 
forecasted for the entire wireless charging market. While stable growth is anticipated 
in  these  sub-  categories,  it's  unlikely  that  they  will  be  the  primary  drivers  of 
overall market expansion. Wireless charging transmitters, expected to steadily 
rise  over  the  years  with  the  widespread  of  wireless-capable  consumer 
electronics devices. The industrial wireless transmitter market anticipates a robust 
expansion, reflecting specific industrial needs, while the in-car wireless charging sector 
gains momentum, propelled by consumer preferences for convenience. The broader 
wireless charging market exhibits widespread adoption, showcasing a diverse range 
of pricing options catering to varying consumer preferences, from premium to budget-
friendly choices. These trends underscore the dynamic and consumer-driven nature of 
the evolving wireless charging landscape. 

Current situation of transmitters based on PD 

Table 9 and Figure 8 show the summary of the transmitters’ supported technologies 
collected within the PD depending on their type. 

Table 9 – Share of supported technologies for transmitters 

Standalone transmitters 

Supported Technology 

Amount 

Share 

MagSafe 

Qi 

Qi + Xiaomi 

Qi + MagSafe 

Qi2 

Qi + Oppo 

Qi + Vivo 

Total 

Source: Product database 

10% 

68% 

2% 

15% 

4% 

1% 

1% 

100% 

10 

71 

2 

16 

4 

1 

1 

105 

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Study on wireless charging technologies 

Figure 9 – Share of supported technologies for transmitters 

4%

10%

19%

68%

MagSafe

Qi

Qi + Proprietary

Qi2

Source: Product database 

The table indicates the dominance of Qi standard as over 86% of all transmitters are 
compatible  with  at  least  Qi,  which  is  in  line  with  the  findings  of  the  Predecessor 
Study.  Notable  change  in  case  of  Qi  compatibile  transmitters,  the  increase  of 
proprietary  solutions  that  is  fully  compatible  with  Qi24  but  have  unique  features  that 
distinguishes  them  from  standard  Qi  transmitters  (Xiaomi,  Oppo,  Vivo).  Huawei 
transmitters are not included in the PD due to their release date (Huawei transmitters 
with release date after 2021 have not been found), but they are also available on the 
market and the previous statement is also true for them as well. 

10 items (9%) were found that have no Qi certification, but compatible only with Apple 
products as they are using MagSafe standard. This is a novelty compared to 2021 as 
only one Apple Watch charger was highlighted in the Predecessor Study’s database. 

Despite  the  extensive  desk  research  and  expert  interviews,  no  further  transmitters 
have  been  identified  that  are  available  on  the  B2C  market  and  support  different 
technology than the above mentioned standards. Similarly to the Predecessor Study, 
transmitters by jjPlus were found that support AirFuel Resonant standard. However, 
they  were  not  highlighted  in  the  PD  due  to  their  release  date  and  potentially  same 
power level under 33W. 

Proportion of Qi compatible transmitters on the B2C market could be even higher due 
to excluded items with release date before 2021. Additionally, with Qi2, fragmentation 
on the market might further decrease organically on mid-term as it comabines both Qi 
and MagSafe standards. Current and future dominance of Qi/Qi2 might be seen 
from  the  products  of  the  biggest  wireless  charging  companies  (according  to 
Statista). 8 out of the 10 biggest companies either have Qi certified products or 
products that are using MagSafe. For the remaining 2 companies (PowerSphyr and 
Wi-Charge) B2C products have not been found during data collection and also they 

24 Devices that are compatible with Qi, can be charged wirellessly with those transmitters. 

88 

 
 
 
Study on wireless charging technologies 

are  operating  with  different  technology  on  the  B2B  market  as  it  was  highlighted  in 
section 3.2.1 and 3.2.2. 

Considering  the  standalone  transmitters’  potential  power  level,  it  can  be  seen  that 
proprietary  solutions’  maximum  power  level  are  higher  compared  to  standard  Qi 
transmitters.  This  would  indicate  shorter  charging  time  and  could  differentiate  them 
based on energy efficiency as well (in case the device also supports the solution). The 
development of Qi standard to increase maximum power level from 15W to  25W or 
above could be under consideration based on expert interviews to shorten charging 
time. Although, it was highlighted that further increase of power level could be difficult 
on-long  term  with  Qi.  Higher  power  level  is  technically  feasible,  but  the  higher  the 
power  transmission  is,  the  greater  the  harmful  emissions  are  that  might  cause 
difficulties  to  comply  with  regulations.  Therefore,  certain  development  could  be 
expected in the market in terms of potential power level. The maximum potential power 
level of supported technologies according to the PD is presented as follows 

Table 10 – Supported standards by input power level 

Number of standalone transmitters 

Standard 
(max power level) 

MagSafe (15W) 

Qi (15W) 

Qi + Xiaomi (100W) 

Qi + MagSafe (15W) 

Qi2 (15W) 

Qi + Oppo (50W) 

Qi + Vivo (50W) 

N/A 

Total 

Source: Product database 

Below 15 W 

Over 15 W 

Total 

9 

71 

- 

16 

4 

- 

- 

-  

100 

- 

- 

2 

- 

- 

1 

1 

- 

4 

9 

71 

2 

16 

4 

1 

1 

1 

105 

As  Table  10  indicates,  Xiaomi,  Oppo  and  Vivo,  that  are  all  top  smartphone 
manufacturers have their own wireless charging solutions with 50W or higher 
maximum power level. Huawei also needs to be mentioned within this category as 
the brand has standalone transmitter with 50W power level25. 

Where information was available, approximately 87% of the standalone transmitters’ 
connector types were USB-C while the remaining ones had USB-A, micro-USB or 
had  no  input  connector  (Table  11  and  Figure  9).  Although,  information  was  not 
commonly available during data collection (only in the case of 40% of total standalone 
transmitters), it is reasonable to expect similar dominance of USB-C within the whole 

25 Huawei: https://consumer.huawei.com/en/accessories/supercharge-wireless-charger-stand-max-

50w/, downloaded February 08, 2024 

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Study on wireless charging technologies 

sample. The dominance of USB-C is even greater compared to the Predecessor Study, 
corresponding  with  market  and  regulatory  trends  (Common  Charger  Directive  (EU 
2022/2380)).  

Table 11 – Connector types of standalone transmitters 

Connector type 

Amount 

USB-C 

USB-A 

micro-USB 

No input connector 

N/A 

Total 

Source: Product database 

39 

1 

3 

2 

68 

105 

Share 

34% 

1% 

3% 

2% 

60% 

100% 

Figure 10 – Connector types of standalone transmitters*  

*where these informations were available 

4%

7%

2%

87%

USB-C

USB-A

micro-USB

No input connector

Source: Product database 

Regarding  the  input  parameters  of  the  standalone  transmitters,  similar  observation 
could be concluded as in the Predecessor Study. Majority of the transmitters, where 
information was available, require 12V or less and 3A or less. The most common 
cases are the standard 5V with 3A, or 9V with 2A. Few exception can be seen in 
case  of  the  proprietary  solutions  with  higher  power  level,  where  20V  and  3-6A  is 
necessary  to  achieve  the  maximum  performance.  However,  these  items  could  also 
work with regular EPS as well, albeit with lower charging performance. 

Although, very limited or no information was available for required V and A level in case 
of  the  majority  of  standalone  transmitters,  substantially  different  result  could  not  be 
expected considering the transmitters’ potential power level and their connector type. 

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Study on wireless charging technologies 

Nonetheless, it should be noted that the maximum performance of the transmitters with 
proprietary solutions (50W or higher) could not be available for the consumers without 
appropriate EPS unit which is usually highlighted in the manufacturers’ website. 

Interesting  aspect  of  the  standalone  transmitters  that  how  many  charging  pads  are 
within one product (Table 12). Almost every forth item has more than one charging 
pads  which  is  a  13  percentage  points  increase  compared  to  the  previous 
database.  This  could  be  attributed  to  the  trend  where  users  possess  an  increasing 
number of wireless charging capable devices, but the current limitation of Qi standard 
does not allow to charge multiple device with one coil at the same time. Potentially, 
manufacturers design transmitters with multiple charging pads in order to differentiate 
their products and attract customers. 

Table 12 – Number charging pads in standalone transmitters 

Standalone transmitters 

Number of charging pads 

Amount 

1 

2 

3 

4 

Total 

Source: Product database 

80 

7 

17 

1 

105 

Share 

76% 

7% 

16% 

1% 

100% 

Moreover, standalone transmitters with multiple charging pads are typically designed 
for one smartphone and one or two earbuds case or smartwatch. However, most of 
the chargers are still mainly designed for smartphones as it was already outlined in the 
Predecessor Study. 

In  addition  to  the  standalone  transmitters,  the  market  also  provides  embedded 
wireless chargers where the transmitter is integrated into other products. Contrary to 
the Predecessor Study, greater variety of examples are presented in the Table 13 
below (8 vs.13 type) and almost twice as much examples have been collected (18 
vs.  34  item)  that  indicate  the  expansion  of  embedded  solutions.  New  types  of 
embedded  solutions  are  for  instance  shelf,  car  phone  mount,  beverage  warmers. 
Nevertheless,  the  most  common  cases  in  addition  to  the  prevalent  power  banks, 
charging docks and lamps outlined in the Predecessor Study, now incorporate clocks 
and car phone mounts as well. 

Regarding  to  embedded  wireless  chargers  into  furnitures,  the  experts  being 
interviewed only see limited potential in the furniture industry, as no strategic business 
intention in this direction can be identified, and implementation might require greater 
effort from furniture manufacturers as they need to acquire expertise to incorporate this 
technology. Potentially, technically defective chargers pose a risk to the reputation of 
furniture manufacturers not having the human and professional capacity to fix these 
troubles.  

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Study on wireless charging technologies 

Table 13 – Embedded device type summary 

Embedded transmitters 

Embedded device 

Amount 

Beverage Warmer 

Car phone mount 

Clock 

Desk mat 

Dock 

Lamp 

Mousepad 

Power bank 

Shelf 

Speaker 

Table 

Tray 

UV-Sanitiser 

Source: Product database 

1 

5 

5 

1 

3 

6 

2 

6 

1 

1 

1 

1 

1 

Share 

2.9% 

14.7% 

14.7% 

2.9% 

8.8% 

17.6% 

5.9% 

17.6% 

2.9% 

2.9% 

2.9% 

2.9% 

2.9% 

Though  in-car  embedded  wireless  chargers  are  not  included  in  the  PD,  these 
embedded  transmitters  are  increasingly  prevalent,  notably  within  leading  car 
brands according to the performed research activities. The dominant standard in 
this area is the Qi standard, adopted by various manufacturers. For instance, Ford26 
integrates  wireless  charging  pads  within  their  vehicles,  supporting  Qi-
compatible  devices.  Similarly,  Hyundai27  offers  Qi-certified  wireless  charging 
systems across their entire lineup for 2024. This is in line with findings from expert 
interviews.  More  concretely,  many  Korean  automotive  manufacturers  have  built  in 
wireless  charging  –  mainly  Qi  standard  –  even  in  their  low-cost  tier  cars.  It  is  not 
expensive, but actually much more convenient to use due to the ease of picking up 
and  putting  down  the  phone.  Unlike  traditional  cables  such  as  USB-C  or  USB-A 
connector that require unplugging and replugging which comes with safety concerns 
in  congested  traffic  situations.  Wireless  charging  in  cars  might  offer  additional 
convenience, as the mobile device is usually connected via BT and wireless charging 
could be done in parallel on another frequency or on a charging pad with Qi standard. 
There are several places in cars that meet relatively strict form requirements (smooth, 
flat surface), such as the centre console. The widespread adoption of such technology 
underscores its importance in modern automotive design and consumer preferences, 
reflecting  a  shift  towards  seamless  integration  of  technological  innovations  into  the 
driving experience. 

26 Ford: https://www.ford.com/support/how-tos/more-vehicle-topics/dashboard-and-center-
console/what-is-the-wireless-charging-pad-feature/, downloaded February 12, 2024. 

27 Hyundai: https://www.autonationhyundaitempe.com/research/wireless-charging.htm, downloaded 

February 12, 2024. 

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Study on wireless charging technologies 

5.1.2. 

Add-on receivers 

The  Predecessor  Study  highlighted  that  add-on  receivers  are  also  available  on  the 
market  that  enable  wireless  charging  for  devices  that  do  not  have  built-in  wireless 
charging  capabilities.  This  segment  was  already  in  decline  due  to  the  expension  of 
wireless charging according to the Predecessor Study which was confirmed during the 
research activities of the present Study.  

This  Study  found  very  limited  information  on  newly  released  add-on  receivers 
since  2021.  All  of  the  found  examples  support  Qi  technology  as  it  is  shown  in 
Table  14,  there  were  no  available  information  on  other  product  that  support  other 
technologies exclusively. Despite that there were no available information on release 
date of three out of four add-on receivers, these items were also collected as they were 
not included in the Predecessor Study’s product database. 

Table 14 – Technology supported by add-on receivers 

Supported technology 

Amount 

Qi 

Qi and MagSafe 

Total 

Source: Product database 

3 

1 

4 

Share 

75% 

25% 

100% 

The  Predecessor  Study  also  analysed  the  connector  types  of  add-on  receivers  and 
found various examples (e.g.: USB-C, Micro USB, Lightning, etc.) with the dominance 
of USB-C (42% of the sample). However, this aspect is less relevant for the present 
Study  due  to  the  introduction  of  the  Common  Charger  Directive  and  its  indirect 
influence on products categories currently not covered (such as the add-on receivers). 
Therefore, in case there would be a market need for add-on receivers, their connector 
type would not cause interoperability issues because they could be harmonised. 

5.2.  Device categories 

Devices were categorised according to their power level and form factor, following the 
methodology of the Predecessor Study, as these factors are primary constraints on the 
usability  of  wireless  charging  technologies,  thereby  influencing  fragmentation  on 
market  segments.  Therefore, three  device  categories  are  presented in  the  following 
subsections: Low power electronics; Medium-high power electronics; Other electronic 
devices. 

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Study on wireless charging technologies 

5.2.1.  Low power electronics 

Category overview  

The low power electronics category includes all consumer electronics that operate with 
5W or less. Similarly to the Predecessor Study, it contains the following device types: 

●  Smartwatch 

●  Earbuds and headset (including headphones) 

●  Mice 

●  Keyboard 

●  Digital camera 

●  E-reader 

●  Smart pen 

●  Smart glasses 

It needs to be highlighted that very limited information were available on power levels 
for the above mentioned device types. However, it was assumed that these items can 
be categorised as low power electronics based on the Predecessor Study and non-
wireless capable devices’ power level. 

Market data related to low power electronics 

Various  market  report  has  been  reviewed  regarding  the  above  mentioned  product 
categories within the low power electronics category. Based on that, smartwatches and 
earbuds  market  were  concluded  as  the  two  biggest  category.  Additionally,  the  two 
product  categories’  widespread  popularity  and  prevalent  integration  of  wireless 
charging  technology  was  also  confirmed  during  the  expert  interviews.  Therefore, 
special attention was given to these categories. 

Regarding the overall market of low power electronics, Europe is expected to hold a 
robust market for multiple wearable devices (such as smart watches, health and fitness 
trackers, wrist sport computers, connected watches und locators), which is backed by 
statistical  data  from  2022,  with  around  7.2  million  wearable  devices  sold  just  in 
Germany, marking almost 4% of global shipment and rushing up from 2 million units in 
2015. Also the Central Eastern European (CEE) region shows no notable difference in 
demand based on research data for wearables including smartwatches and earbuds 
accounting for 43.9% of wireless and smart device usage in Czechian households in 
2022.  Global  smartwatch,  wristband  and  other  wearable  shipments  reached  almost 
200 million units and are predicted to hit over 240 million units in 2027, with European 

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Study on wireless charging technologies 

countries estimated to have a fair share in shipment. (Clinton, 2024; Gfu, 2023; IDC, 
2023).  

Smartwatches 

The smartwatch market has experienced  remarkable growth and projected to reach 
47.94 billion U.S dollars in 2024, with an anticipated CAGR of 6.84%, culminating in 
a  projected  market  volume  of  62.46  billion  U.S  dollars  by  2028  (Statista,  2024). 
According  to  Versus.com,  a  substantial  38%  of  smartwatch  models  incorporate 
wireless charging capability. This data suggests a prevalent integration of wireless 
charging  technology  within  the  smartwatch  market,  indicating  a  strong  consumer 
demand for this feature. The higher adoption rate in smartwatches compared to other 
electronic devices such as smartphones and tablets could be due to several reasons 
(easier  to  adopt  port-free  design,  lower  power  requirements  compared,  easier  to 
incorporate wireless charging coils without notably increasing the size or weight of the 
device). It also implies that wireless charging is becoming a standard and attractive 
feature for smartwatch consumers. As the smartwatch market is expected to continue 
to  expand,  the  prevalence  of  wireless  charging  may  serve  as  a  substential  factor 
influencing consumer choices and contributing to the overall positive trajectory of the 
wireless charging industry.  

Earbuds  

The global true wireless stereo earbuds market, valued at 35.37 billion U.S dollars in 
2021, is poised to register a remarkable CAGR of 34.9% from 2022 to 2030. (Grand 
View  Research).  Notably,  14%  of  earbud  model  types  are  reported  to  feature 
wireless  charging  capability,  as  per  Versus.com.  This  data  suggests  a  moderate 
integration  of  wireless  charging  technology  within  earbuds,  indicating  an  existing 
preference  among  consumers  for  this  convenient  charging  feature.  However,  a 
customer preference survey stated, that over 50 percent of the respondents consider 
sound quality, price, comfort in the ear, as well as battery life as the most important 
factors  influencing  their  choice.  Only  25%  said,  that  wireless  capability  is  an 
important purchase criteria (Qualcomm, 2020). As seen now, wireless capability is 
deemed  less  crucial  by  consumers.  As  the  earbud  market  continues  to  evolve,  the 
adoption of wireless charging may play a more substential role in shaping consumer 
choices and driving innovation within the industry. 

Other products in this category 

In addition to smartwatches and earbuds, low power electronics encompasses several 
other products as well. The global computer mice market, saw a sizeable increase, 
reaching 1,694.5 million U.S. dollars in 2022 (Precision Reports, 2021). Similarly, the 
computer  keyboard  market  experienced  remarkable  revenue,  totaling  4,870.3 
million U.S. dollars in 2023 (Future Market Insights, 2024). Additionally, the digital 
camera  market,  as  surged  to  a  size  of  7.9  billion  U.S.  dollars  in  the  same  year 
(IMARC, 2022). The e-reader market, at 350.5 million U.S. dollars in 2022, has also 
shown notable valuation (IMARC, 2023). The global smart pen market was valued 

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Study on wireless charging technologies 

at about 1 billion U.S. dollars in 2022 (Dhapte, 2024), while the global smart glasses 
market size was valued at 1,232 million U.S. dollars in 2022 (Grand View Research, 
2022). When comparing these figures to the smartwatch and earbud markets, a clear 
distinction  emerges.  While  lower  power  electronics,  such  as  computer  mice, 
keyboards, digital cameras, e-readers, smart pens, and smart glasses, play substential 
roles in their respective niches, their market sizes, although substantial, do not reach 
the same scale as the previously mentioned smartwatch (47.94 billion U.S. dollars in 
2024) and earbud (35.37 billion U.S dollars in 2021) markets.  

Current Situation of low power electronics based on the PD 

This chapter presents a comprehensive analysis of low power products, delving into 
their  supported  wireless  technologies,  connections  between  form  factors  and 
supported  technologies,  and  exploring  the  limitations  of  wireless  charging  across 
different product types. 

The  examination  of  lower  power  devices  and  their  corresponding  wireless  charging 
technologies  offers  valuable  perspectives  on  the  evolving  landscape  of  wireless 
charging  in  diverse  product  categories.  This  study  encompasses  an  analysis  of  90 
products spanning across 7 distinct product categories (Table 15).  

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Table 15 – Supported wireless charging technologies - low power electronics 

Supported Technology 

Amount 

Smart watch 

Qi28 + Huawei 

Magsafe 

Qi 

Xiaomi 

Qi + vivo 

Oppo 

Qi + Google 

Qi 

Qi + Magsafe 

Qi 

Qi 

Qi 

Qi 

Proprietary (Apple) 

Source: Product database 

15 

10 

10 

7 

2 

2 

1 

Earbuds and headsets 

32 

1 

Mice 

4 

E-reader 

1 

Digital camera 

1 

Keyboard 

1 

Smart pen 

1 

Share 

31.9% 

21.3% 

21.3% 

14.9% 

4.3% 

4.3% 

2.1% 

97% 

3% 

100% 

100% 

100% 

100% 

100% 

In  the  realm  of  smartwatches,  a  significant  proportion,  amounting  to  59.6%,  boasts 
compatibility  with  or  integration  of  Qi  technology  based  on  desk  research  and 
manufacturers  feedbacks.  Another  substantial  portion,  representing  38.3%  of  the 
market  (three  out  of  nine  manufacturer),  presents  itself  as  Qi  compatible  while 
simultaneously  integrating  proprietary  solutions  (Figure  10).  This  signifies  that  a 
notable array of smartwatches implement a distinctive wireless charging mechanism 
devised by the manufacturer. However, these proprietary solutions are not necessarily 
backward compatible with all Qi certified transmitters. This is exemplified by Huawei’s 
proprietary  solution  which  is  only  compatible  with  Qi  v1.3.3  and  newer  standard. 
Furthermore, the prevalence of proprietary solutions extends its reach, encompassing 
40.4%  of  the  smartwatch  landscape.  This  indicates  that  majority  of  manufacturers 
(three out of nine) opt for charging methods tailored specifically to their devices, rather 
than relying solely or partly on Qi standard. Conversely, the presence of smartwatches 
exclusively  adhering  to  the  Qi  standard  is  notably  lower  (three  out  of  nine  brand), 

28 Only with Qi v1.3.3 standard 

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Study on wireless charging technologies 

constituting only 21.3% of the market. This implies that while Qi compatibility retains 
relevance, it does not emerge as the prevailing strategy embraced by manufacturers.  

Figure 11 – Supported wireless charging technologies among smartwatches 

4.3%

14.9%

38.3%

21.3%

Qi + Propriatary solutions

Qi

Magsafe

Xiaomi

Oppo

21.3%

Source: Product database 

Relatively high fragmentation on the smartwatch market could be accounted to shape-
related issues.  The  shape and  size of  smartwatches  are  not  completely  suitable  for 
wireless  charging  technology.  It  requires  some  specific  design  features  in  the 
smartwatches that their manufacturers do not necessarily want to add. Therefore, the 
smartwatch manufacturers usually develop own proprietary solutions that best fit the 
shape  of  their  own  watches.  This  highlights  the  diversity  of  charging  technologies 
present in the smartwatch market and the importance of form factor.  

The  findings  from the  Predecessor  Study’s  findings  indicate that  Qi  technology was 
predominant  in  the  low-power  electronics  product  category.  This  pattern  was 
reaffirmed  by  the  analysis  with  earbuds,  mice  and  new  product  types  (included 
keyboard,  digital  camera,  e-reader)  showing  100%  compatibility  with  Qi 
technology.  This  consistency underscores  the  reliability  and  universality  of  Qi  as a 
wireless charging standard across diverse device categories. Additionally, it is in line 
with  highlights  from  expert  interviews,  where  some  experts  listed  the  flagship 
categories that can drive the spread of Qi standard: small accessories, smartwatches, 
smart bracelets, fitness trackers, earbuds, styluses, digital pens, keyboards for tablets.  

As far as earbuds are concerned, it was generally agreed that this product category is 
already the target market for the Qi standard. The obvious market for Qi technology is 
bluetooth  true  wireless  earphones  with  the  opportunity  of  being  charged  in  a  small 
case, which already comply with the Qi standard, and they do not require high-speed 
charging. It is important to mention, that in case of bluetooth true wireless earphones 
wireless charging takes place only between the transmitter and the charging case of 
the  earphones  and  not  between  the  transmitter  and  the  earbuds  nor  between  the 
charging case and the earbuds. The earbuds are typically charged by their charging 
case with direct physical connection. In that respect, it is crucial to note that in the case 

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of  wireless  charging,  the  form  factors  play  a  pivotal  role  in  determining  which 
products  can  be  Qi-compatible  (as  it  was  already  highlighted  in  case  of 
smartwatches). For instance, while earbuds themselves cannot directly integrate Qi 
technology due to their small size and internal components, their charging cases can 
be  Qi-enabled,  allowing  for  convenient  charging.  Similarly,  larger  devices  like  e-
readers,  digital  cameras,  and  keyboards  have  ample  space  to  incorporate  Qi-
compatible  components,  making  them  seamlessly  adaptable  to  wireless  charging 
capabilities.  Thus,  while  the  Qi  standard  demonstrates  remarkable  versatility,  the 
physical design of each product type influences its wireless charging compatibility. 

Conversely,  smart  pens,  due  to  their  slender  form  factor  and  limited  internal 
space, are not Qi-capable. As a result, proprietary (true wireless) charging solutions 
are  often  employed,  highlighting 
in 
accommodating unique form factors within wireless charging technology. 

tailored  approaches 

the  necessity 

for 

Despite the fact that the Predecessor Study presented one wireless charging capable 
smart glasses, this examination did not contain any of these products. Smart glasses' 
compact design pose challenges for integrating wireless charging technology. 
While  various  solutions  have  been  explored,  ranging  from  tech  brands  to  glasses 
manufacturers  like  Ray-Ban,  wireless  charging  solutions  were  not  found.  Some 
products have adopted an earbud-like solution, where the charging case is chargeable 
and,  in  turn,  charges  the  glasses.  However,  these  implementations  prioritise  wired 
charging solutions to maximise charging power and efficiency. 

In summary, the analysis highlights the prevalence of Qi technology as the dominant 
wireless charging standard across lower power devices, despite the presence of 
manufacturer-specific  solutions  in  smartwatches  and  smart  pens.  The  findings 
underscore  the  reliability  of  Qi  compatibility  across  different  device  types,  while 
highlight  standardisation  potential  in  the  field  of  smart  watches  due  to  higher 
fragmentation level. 

5.2.2.  Medium-high power electronics 

Category overview of medium-high power electronics 

This  section  delves  into  the  realm  of  medium-high  power  electronics,  specifically 
focusing on wireless charging technologies that exceed the 5W threshold. This study 
builds  upon  the  terminology  established  in  the  Predecessor  Study,  maintaining  the 
definition of medium-high power  electronics (above 5W)  while shedding light on the 
latest advancements and market dynamics. 

This  category  is  dominated  primarily  by  smartphones  with  a  limited  presence  of 
tablets.  Navigating  through  the  market  overview  reveals  that  the  landscape  is 
dominated by the widespread adoption of Qi technology. 

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Study on wireless charging technologies 

Qi  standard  has  become  dominant  for  wireless  charging  in  recent  years,  ensuring 
interoperability across a range of devices. However, as the need for faster charging 
solutions intensifies, Qi's limitations have become apparent. Recognising this demand 
for speed and efficiency, other manufacturers, especially those from the Asian market, 
have  introduced  their  proprietary  standards.  These  standards  not  only  maintain 
compatibility with Qi but also push the boundaries by enabling power levels of 50 or 
more watts. 

This  section  will  dive  deeper  into  the  factors  driving  the  need  for  faster  charging, 
exploring how alternative standards have emerged to cater to this demand. While still 
aligning  with  Qi  compatibility,  these  advanced  standards  promise  to  redefine  the 
capabilities of medium-high power wireless charging.  

Market data related to medium-high power eletronics 

Smartphones  

The  smartphone  market,  positioned  as  one  of  the  largest  category  in  consumer 
electronics, witnessed a substential 1,114.6 million unit shipments globally in 2023, 
with Statista projecting a moderate increase to 1,250.7 million by 2027 at a 2.33% 
CAGR (Statista 2023). Several interviews conducted with industry representants for 
the present Study similarly mentioned a slowing growth rate on the smartphone market, 
which is seen to be saturating in European countries.  

In 2024, the global revenue in the smartphones market worldwide will reach a 467.6 
billion  U.S.  dollars  and projecting  to  reach  542.47  billion  U.S.  dollars  by 2028, 
indicating a robust financial landscape for manufacturers and investors alike (Statista, 
2024).  According  to  Versus.com,  13%  of  smartphone  models  feature  wireless 
charging  capability.  This  data  indicates  a  relatively  modest  integration  of  wireless 
charging  technology  across  various  smartphone  types.  While  wireless  charging  is 
present in a noteworthy percentage, it has not yet become a ubiquitous standard in the 
broader smartphone market. On the other hand, these devices show a rapid turn rate 
with  products  being  replaced  to  newer  models  approximately  every  2-3  years  by 
consumers  (Statista,  2023),  thus  allowing  for  faster  adoption  of  newer  technologies 
than in other sectors like automotive sector, the average new car is kept for 8.4 years 
according to iSeeCars (2023), an automotive research firm.. The adoption rate may be 
influenced  by  factors  such  as  cost  considerations,  technological  limitations,  and 
varying priorities among smartphone manufacturers and consumers.  

According to experts, two distinct consumer preferences are in conflict with each 
other  when  considering  the  choice  between  wired  and  wireless  charging 
options:  the  user  convenience  and  the  speed  of  charging,  namely  power 
transmission. The customers will be in a trade-off situation: either fast charging with 
USB cables and wired solutions, or user convenience with - for the time being - 
lower  charging  speed  and  wireless  solutions.  Nonetheless,  as  the  smartphone 

100 

Study on wireless charging technologies 

market continues to evolve, the trajectory of wireless charging adoption may depend 
on advancements in technology and shifting consumer preferences. 

Tablets 

The tablet market has seen a notable shipment volume, reaching 142.3 million units 
in 2023, with a projected decrease to 135.5 million units by 2027, as reported by 
Statista with a -1% CAGR (Statista 2023). In term of revenue, in 2024, the tablets 
market worldwide is projected to generate a revenue of 53.7 billion U.S dollars, 
estimated to reach 59.87 billion U.S. dollars in 2028 (Statista, 2024). According to 
Versus.com, only 2% of tablet model types are equipped with wireless charging 
capability. This data suggests that, despite the presence of tablets in the market, the 
adoption of wireless charging in this market is limited. The low percentage indicates 
that  wireless  charging  has  not  become  a  widespread  standard  feature  for  tablets. 
Possible  explanation  for  this  limited  adoption  could  be  the  practical  challenges 
associated with wireless charging in larger devices like tablets. Unlike smaller devices 
such as smartphones, tablets typically require higher power input for efficient charging. 
Current  wireless  charging  technologies  might  not  be  able  to  deliver  the  necessary 
power levels efficiently, resulting in slower charging speeds or even impracticality due 
to  excessive  energy  consumption.  These  factors  contribute  to  the  hesitation  among 
tablet  manufacturers  to  widely  implement  wireless  charging  technology  in  their 
products. In conclusion, it is projected that substential growth in the wireless charging 
market for tablets will not be achieved if no technical breakthroughs occur. 

Current Situation of the medium-high power electronics based on the PD 

This  chapter  presents  an  analysis  of  wireless-capable  medium-high  power  devices, 
more concretely, smartphones and tablets based on the PD. The Study examines the 
proportions of these devices in the database and compare the findings with external 
sources like Versus.com. The chapter highlights the growing prevalence of wireless-
capable  smartphones  over  the  years,  potentially  reflecting  increasing  consumer 
demand for wireless charging technology. In contrast, tablets show a lower proportion 
of wireless-capable devices, likely due to usage patterns and technological constraints.  

The dominance of  Qi  (or Qi  +  proprietary)  technology  and  the  decline  of  alternative 
wireless charging standards are also discussed in this section. Additionally, the chapter 
explores shifts in input power analysis, indicating a move towards advanced charging 
technologies and higher power levels in the smartphone market which is a remarkable 
change compared to the Predecessor Study.  

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Study on wireless charging technologies 

Table 16 – The proportions of wireless capable medium-high power devices 

Year 

Total number of 
phones 

Wireless capable 

Share 

2021 

2022 

2023 

Total 

2021 

2022 

2023 

Total 

Smartphones 

Tablets 

459 

472 

345 

1276 

20 

30 

35 

85 

36 

56 

49 

141 

3 

- 

- 

3 

8% 

12% 

14% 

11% 

15% 

- 

- 

3.53% 

Source: Product database 

Table 16 shows the proportions of wireless capable medium-high power devices based 
on informations collected on the top 20 smartphone brands available on GSMarena. 
Out  of  1276  smartphones  analysed,  141  are  identified  as  wireless  capable, 
accounting  for  approximately  11%  of  the  total.  This  proportion  demonstrates  a 
consistent  growth  trend  over  the  years,  with  wireless-capable  smartphones 
comprising 8% in 2021 and reaching 14% in 2023. These findings are in alignment with 
data  from  Versus.com,  which  suggests  that  around  13%  of  smartphone  types  are 
wireless  capable,  indicating  a  close  correlation  between  the  database  and  external 
sources.  

In  contrast  to  smartphones,  tablets  exhibit  a  lower  proportion  of  wireless-capable 
devices.  Out  of  85  tablets  analysed,  only  3  are  identified  as  wireless  capable, 
constituting  approximately  3,5%  of  the  total.  This  aligns  closely  with  data  from 
Versus.com,  which  suggests  that  around  2%  of  tablet  types  are  wireless  capable, 
indicating consistency between the study’s database and external sources. 

The lower prevalence of wireless-capable tablets may be attributed to several factors, 
including  differences  in  usage  patterns,  consumer  priorities,  and  technological 
constraints. Unlike smartphones, tablets may not be as heavily relied upon for constant 
usage throughout the day, reducing the demand for wireless charging capabilities. 

102 

Study on wireless charging technologies 

Figure 12 – Average price comparison of wireless capable and 
non-wireless capable products from Xiaomi and Samsung 

1200

1000

800

600

400

200

0

778.31

976.44

370.19

244.78

n=29

n=13

n=33

n=13

Xiaomi

Samsung

NOT wireless capable

Wireless capable

s
r
a

l
l

o
d
S
U

.

Source: Amazon, Walmart, Mobileinto, GSMarena 

for  wireless  charging 

The surge in wireless-capable smartphones is indicative of the escalating consumer 
technology.  Notably,  within  the  premium 
preference 
smartphone  tier,  wireless  charging  capability  stands  out  as  one  of  the 
distinguishing  features  separating  premium  product  lines  from  their  non-
premium  counterparts.  Therefore,  wireless  charging  capable  smartphones  are 
typically  more  expensive  due  to  their  high-end  product  category.  However,  it's 
important to note that even though these phones support wireless charging, they can 
all still be charged using wired solutions if desired. Figure 11 illustrates this, revealing 
that  the  average  price  for  wireless-capable  Samsung  phones  is  almost  four  times 
higher than non-wireless products, while for Xiaomi, it exceeds more than twice the 
price. This data underscores the significance of wireless charging as a distinguishing 
factor in the competitive landscape of smartphones. However, it is important to note 
that while there are  some rare, exceptional cases where non-wireless capable 
devices are more expensive, this is not the prevailing trend. 

Table 17 – Share of supported technologies for medium-high power devices 

Supported technology 

Amount 

Qi (or Qi + proprietary) 

Qi (or Qi + proprietary) 

Source: Product database 

Smartphone 

141 

Tablet 

3 

103 

Share 

100% 

100% 

 
 
Study on wireless charging technologies 

Table 18 – Existing standards in the medium-high power category 

Product 

Supported standards 

Amount 

Share 

Qi 

Qi + Huawei 

Qi + Magsafe 

Qi + Oppo 

Qi + vivo 

Qi + Xiaomi 

Qi + Google 

Qi + Honor 

Qi + Infinix 

Qi + Motorola 

Qi + OnePlus 

Qi + Huawei 

Smartphones 

Tablets 

Source: Product database 

55 

16 

12 

5 

15 

19 

6 

8 

1 

2 

2 

3 

39% 

11.3% 

8.5% 

3.5% 

10.6% 

13.5% 

4.3% 

5.7% 

0.7% 

1.4% 

1.4% 

100% 

Alternative  wireless  charging  technologies  have  experienced  a  decline  in  adoption, 
such as PMA for smartphones (from 2% to 0%) and Touchstone for tablets (from 25% 
to  0%)  compared  to  the  Predecessor  Study.  According  to  the  database,  these 
technologies  have  virtually  disappeared  from  the  market,  with  a  drastic  decrease  in 
their usage compared to the Predecessor Study. This decline could be attributed to 
factors such as limited compatibility, slower charging speeds, and the overwhelming 
dominance of Qi technology. 

Qi  technology  has  solidified  its  position  as  the  dominant  wireless  charging 
standard  for  smartphones  and  tablets  (Table  17  and  Table  18).  With  complete 
exclusivity in the smartphone and tablet market, Qi has established itself as the go-to 
choice  for  manufacturers  and  consumers  alike.  Its  widespread  adoption  can  be 
attributed to its reliability, efficiency, and compatibility across a wide range of devices.  

Despite  Qi's  dominance,  the  landscape  of  wireless  charging  standards  for 
smartphones  has  expanded  with  the  introduction  of  new  elements.  There  is  a 
visible  trend  of  manufacturers  developing  their  own  Qi  +  Proprietary  wireless 
charging  standards  with  higher  power  level  (Figure  12).  This  indicates  a  shift 
towards customisation and proprietary solutions tailored to specific models or brands 
to serve customer needs for higher charging capability. While this approach may 
offer advantages such as tighter integration and enhanced performance, it may poses 
challenges in terms of compatibility and interoperability with devices and charging pads 
from other brands. 

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Study on wireless charging technologies 

Figure 13 – Existing standards in the medium-high power category 

39%

Qi only

Qi + Proprietary

61%

Source: Product database 

EEP  

(up to 15 W) 

Over 15W 

Table 19 – Smartphones’ input power level summary 

Power 

Amount 

Share 

Total 

5W 

7,5W 

10W 

11W 

15W 

18W 

20W 

21W 

23W 

30W 

40W 

50W 

66W 

67W 

100W 

N/A 

3 

2 

1 

1 

42 

1 

1 

1 

3 

7 

2 

52 

3 

2 

1 

19 

34.8% 

51,8% 

2.1% 

1.4% 

0.7% 

0.7% 

29.8% 

0.7% 

0.7% 

0.7% 

2.1% 

5% 

1.4% 

36.9% 

2.1% 

1.4% 

0.7% 

13.5% 

13.5% 

Source: Product database 

The  input  power  analysis  of  the  smartphone  wireless  charging  market  (Table  19) 
reveals several shifts in the industry compared to the Predecessor Study. 

The absence of  Basic Power Profile  (BPP)  in  the  current  database indicates  a 
departure  from  lower  power  profiles  towards  more  advanced  charging 
technologies. This suggests an overarching trend towards faster and more efficient 
charging methods. 

105 

 
 
 
 
Study on wireless charging technologies 

Secondly, there has been a substantial increase in the adoption of Extended Power 
Profile  (EPP),  with  the  proportion  of  devices  utilising  EPP  rising  by  more  than  70% 
compared to the previous study (from 20% to 34.8%). This demonstrates a growing 
preference for higher power profiles among manufacturers and consumers alike, likely 
driven by the demand for faster charging speeds and improved efficiency. 

The  analysis  highlights  a  remarkable  surge  in  the  prevalence  of  devices 
supporting power levels exceeding 15W. This segment has expanded remarkably, 
more  than  sevenfold  (from  7%  to  51,8%),  suggesting  a  concerted  effort  by 
manufacturers  to  meet  the  increasing  demand  for  rapid  charging  solutions. 
Multiple manufacturer have developed their proprietary solution already, mainly from 
the Asian market. This trend is indicative of an industry-wide shift towards prioritising 
faster charging capabilities to enhance user experience.. 

The analysis reveals a clear trend towards higher power profiles and faster charging 
solutions in the smartphone industry. The widespread adoption of EPP, coupled with 
the  surge  in  devices  supporting  over  15W  charging,  signifies  a  concerted  effort  by 
manufacturers  to  meet  the  evolving  needs  and  expectations  of  consumers  in  the 
medium-high power wireless charging sector. 

In conclusion, Qi technology holds a dominant position in the market, with a high 
level  of  compatibility  across  various  devices.  However,  its  current  iteration 
potentially  falls  short  in  terms  of  charging  performance  compared  to  leading 
proprietary  solutions  on  the  market  with  higher  power  level.  Reflecting  on  the 
developments of the past two years and the current competitive landscape, it becomes 
apparent that further technological advancements in  wireless charging solutions are 
nearly  inevitable.  While  this  progress  signifies  potential  improvements,  it  may  also 
introduce complexities to the standardisation process, complicating the establishment 
of a unified charging standard. 

5.2.3.  Other electronic devices 

Similarly to the Predecessor Study, this product category highlights the devices that, 
despite  having  power  level  similar  to  those  mentioned  in  previous  sections,  have 
unique challenges for incorporating wireless charging mainly due to their specific form 
factors.  The  list  of  products  in  the  category  and  their  supported  technologies  are 
summarised in the table below (Table 20). 

Table 20 – Summary of existing standards in other products category 

Toothbrushes and shavers 

Product 

Existing standards 

Toothbrushes 

Proprietary 

Not specified, Unclear Qi compatibility 

Shavers 

Source: Product database 

Qi 

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Study on wireless charging technologies 

As  it  can  be  seen  in  the  table,  only  few  examples  can  be  found  on  the  market  for 
wireless charging capable shavers and toothbrushes. While Qi standard occurs in 
case  of  shavers,  proprietary  solutions  remained  in  use  for  toothbrushes 
compared  to  the  Predecessor  Study’s  database  (for  instance  Oral-B’s  magnetic 
solution29).  

In  overall,  the  Predecessor  Study’s  statement  remain  valid  in  the  past  years.  More 
concretely,  the  penetration  of  wireless  charging  for  these  device  categories  are 
remained low. Additionally, future adaption of Qi standard is unclear for toothbrushes 
and  other  products  with  unique  form,  but  widespread  use  of  the  standard  is  not 
expected on long-term. 

29 Oral-B: https://oralb.com/en-us/products/electric-toothbrushes/io-series-10-rechargeable-electric-

toothbrush-cosmic-black/, downloaded February 02, 2024 

107 

 
 
 
 
 
 
Study on wireless charging technologies 

6. 

Overview of energy efficiency, charging 
performance and interoperability aspects 

This  chapter  provides  an  overview  of  energy  efficiency,  charging  performance,  and 
interoperability aspects in the context of inductive charging, the most common form of 
wireless charging technology currently applied on the consumer electronics market.  

The section is divided into two sub-sections, the literature review and the experiment. 
The literature review section explores existing research, highlighting advancements, 
methodologies as well as relevant insights. Factors such as coil design, alignment, and 
system architectures are examined to understand their impact on these aspects. In the 
experiment,  empirical  findings  derived  from  controlled  experiments  are  presented. 
These experiments aim to supplement existing literature with practical insights into the 
performance  and  interoperability  of  inductive  charging  systems  under  diverse 
conditions. 

By synthesising literature findings and experimental results, this chapter contributes to 
a  deeper  understanding  of  the  dynamics  governing  energy  efficiency,  charging 
performance, and interoperability in inductive charging technologies. Its insights aim to 
support the evaluation of currently available standards on the market. 

6.1.  Technical overview on energy efficiency, charging 

performance and interoperability focusing on inductive 
charging 

The following sections focus on inductive charging, as this has been the only identified 
technology remarkably applied on the consumer electronics market presently.  

Factors influencing energy efficiency of inductive power transfer 

In  the  following,  the  main  factors  influencing  energy  efficiency  of  inductive  power 
transfer and their role in the power transfer process are described briefly. 

The process of linking together two or more coils by a magnetic flux results in mutual 
induction (M), the current flowing in one coil inducing a voltage in the adjacent coil. 
The  amount  of  mutual  inductance  of  the  coils  depends  on  one  hand  on  their  self-
inductance, on the other hand on the coupling and their relative positioning. With 
smaller distance between the two coils, a greater part of the magnetic flux generated 
by the transmitter coil will interact with the receiver coil, resulting in a higher amount of 
induced magnetic flux. Tighter coupling therefore results in smaller energy loss. The 
coupling coefficient (k) indicates a fractional number between 0 and 1: 

• 

If k = 1, the flux leakage is zero due to perfect (100%) magnetic coupling,  

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Study on wireless charging technologies 

•  0.5 < k < 1 indicates tight coupling, 

•  0 < k < 0.5 indicates loose coupling,  

•  k = 0 expresses no inductive coupling. 

The main factors in the coils’ physical appearance which influence energy efficiency 
are  

• 

• 

• 

their  shape  and  size  (ratio  of  diameters)  determining  the  coupling  coefficient 
and therefore the mutual inductance of the coils, 

their radius, coil thickness and permeability of the surrounding medium affecting 
the self-inductance of the two coils. 

their material determining the self-inductance and resistance of the coils as well 
as their intrinsic frequency, thus determining the quality factor, a higher value of 
which decreases system energy loss during power transmission. 

The main factors of the physical combination of the coils are  

• 

• 

their  alignment  and  the  distance  between  the  coils,  determining  the  coupling 
coefficient and thus their mutual inductance. 

the tightness of their coupling, with the load matching factor measuring how tight 
the resonance frequencies are matched (Lu et al., 2016). 

The  dependencies  are  shown  in  equations  (1)  –  (4).  Power  transfer  efficiency  (η) 
therefore depends on the figure of merit (U) and thus on coupling and the coils’ self-
inductance.  

Higher efficiency can therefore be achieved through 

•  higher coupling coefficient (tighter coupling), which is dependent on 

•  better alignment, 
• 
lower distance, 
•  shape of the coils, 
• 

ratio of the coil diameters 

•  higher self-inductance of the coils,  

•  higher frequency, 

• 

lower resistance of the coils 

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Figure 14 – Energy efficiency factors 

𝑄 =

ω𝐿
R

𝑀 = 𝑘√𝐿𝑡𝐿𝑟 

𝑈 = 𝑘√𝑄𝑡𝑄𝑟 

𝑄𝑡 =

𝑄𝑟 =

ω𝐿𝑡
𝑅𝑡

ω𝐿𝑟
𝑅𝑟

𝑈2

(1 +   √1 +   𝑈2)

2 

Source: KPMG, 2024 based on Lu et al., 2016; Alhazmi & Albugami, 2023 

(1) Quality factor: 

(2) Mutual inductance an coupling coefficient: 

(3) Total efficiency figure of merit: 

(4) Maximised efficiency of power transfer: 

𝜂𝑜𝑝𝑡 =  

Source: Kesler, 2013; Kanaan & Sabaawi, 2022 

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Study on wireless charging technologies 

Due  to  the  factors  influencing  each  other,  efficiency  can  only  be determined  for the 
complete charging system embracing the EPS, cables, transmitter, receiver and the 
device. With wireless charging, the system is divided and leaves space for dynamic 
combinations, which implies many unknown variables: 

•  When determining efficiency levels of the transmitter, there are multiple possible 

combinations with different receivers built into various devices.  

• 

• 

In setups without magnetic attachment, even the coupling can vary based on 
how the device happens to be put on the charger, which indicates a situational 
variable.  

In case there is no EPS bundled with the charger, this is another variable with 
different options influencing power levels and efficiency. 

This  illustrates  why  energy  efficiency  of  wireless  charging  is  difficult  to  determine 
universally. It depends on the unique combination of the split charging system, with 
many  variables  influencing  power  transfer  based  on  features  of  the  transmitter  and 
receiver, but also the power supply and load. Due to the unique geometry and design 
of  every  coil,  mathematical  modelling  of  the  coil's  properties  is  difficult  (Alhazmi  & 
Albugami,  2023).  Therefore,  a  universally  standardised  energy  efficiency  level 
could  only  be  reached  by  a  standardised  transmitter  combined  with 
standardised receivers and no room for alignment differences. This theoretically 
could be achievable within product categories, but makes it difficult to create a standard 
overarching different product types and bearing with the same power levels.  

A similar conclusion was drawn by the WPC Energy Star Task Force during the attempt 
to  develop  an  efficiency-test  protocol  to  rank  Qi  transmitters  based  on  efficiency  of 
power  transfer.  As  the  receiver  and  transmitter  interact  with  each  other,  both 
influencing the energy efficiency of the charging system as a whole, it was found that 
such  a  ranking  of  transmitters  for  more  than  one  receiver  design  is  not  possible 
(Perzow, 2022). This basically means that any ranking of efficiency can be made just 
for specific pairs of trensmitters an receivers, not for the transmitter itself as it can be 
combined  with  various  receivers,  leading  to  different  outcomes  in  energy  efficiency. 
Many smartphone brands recommend the usage of proprietary chargers for charging 
phones  of  the  same  brand,  thus  being  able  to  optimise  efficiency  for  that  setup. 
Interoperability  with  other  wireless  chargers  might  be existing,  but  with  lower  power 
transfer efficiency.  

This also explains the wide range of efficiency levels which can be experienced with 
inductive charging: it is shown that 50%-80% charging efficiency can be achieved 
within several centimeters charging distance for IPT systems (Lu et al., 2016).  

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Energy losses at conversion and transmission points 

Another  issue  are  energy  losses at  multiple  sections  of  the  power  transfer  process. 
With  wired  charging,  DC  power  is  transferred  from  the  EPS  directly  to  the  load  via 
cable. For wireless power, there are several conversions necessary which consume 
energy. As the basic principle of inductive wireless charging relies on electric current 
induced by an alternating electromagnetic field, DC power from the EPS needs to be 
converted to AC to trigger power transfer, and then back from AC to DC after being 
received by the device in order to feed the load.  

Figure 15 – Basic components of the IPT system 

Source: Alhazmi & Albugami, 2023 (steps where energy loss is likely to occur have been highlighted by 
KPMG) 

Overall, energy loss occurs at the following steps:  

1.  Original power level from the power supply converted by the transmitter, 
2.  Power transfer between transmitter and receiver, 
3.  Power conversion by the receiver to feed the load. 

It has to be noted that 1. and 3. also occur with wired charging, so the difference in 
energy efficiency derives from the added step of between transmitter and receiver, with 
undetermined efficiency when used in different combinations. 

In the realm of wireless power, the figures typically provided relate to the power output 
at  the  charging  pad  rather  than  the  actual  power  reaching  the  phone's  battery. 
Therefore, although the charging pad may boast a capability of 100W, the phone might 
only receive around 80W or even less.(Triggs, 2023)  

Standby losses30 also occur with inductive chargers, with a range of 130 – 810 mW 
reported by the  WPC  Energy  Star  Task Force  during  their  experiment.  Conclusions 
were drawn that „reducing the average standby power of wireless power transmitters 

30 Standby loss, also referred to as quiescent power is the power-dissipation from the transmitter when 

no receiver is present (Perzow, 2022). 

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by 50% could save as much energy in a 24 hour period as improving the full-power 
efficiency by 10%” (Perzow, 2022). 

Energy  loss  occurs  also  due  to  heat  generated  by  eddy  currents,  which  emerge 
during  the  process  of  induction  and  cause  heat  being  transferred  to  the  device  by 
conduction, as the inductive charging pad and the device are normally physically close 
to each other during power transfer. As the battery of a phone is usually placed close 
to  the  receiver  with  limited  protection  against  heat,  heat  generation  during  wireless 
charging influences the temperature surrounding the battery. This is even increased in 
cases  of  misalignment,  when  the  device  is  not  properly  put  on  the  charger.  As  a 
compensation, transmitter power is increased or frequency is adjusted, which leads to 
increased  heat  generation,  lowering  the  charging  efficiency  and  raising  the  risk  of 
internal component damage in the device and eventually in the charging pad as well. 
(Loveridge et al., 2019). 

Mitigation techniques of temperature rise are  

-  passive  heat  dissipation,  where  heat  absorbing  materials,  structures  and 
designs like a heat sink are applied (e.g. in the housing of the charger), which 
naturally dissipate heat into the air proportionally to the size of the heat sink, 
-  active  heat  dissipation  or  forced  cooling  with  e.g.  a  fan  (air  cooling),  liquid 

cooling or heat pipes, 

as described in Electronic Products, 2011; Peterson, 2021; QST Products, 2018; 
Trumony Techs, 2022. 

On the other hand, forced cooling with a fan requires  a minimal  size of the charger 
housing, making charging pads bigger or bulkier. While there are recommendations for 
shielding, no specific requirements for active heat dissipation can be found in the Qi 
specifications.  Temperature  is  monitored  by  communication  protocols  which  control 
power levels of the transmitter according to the information received from the device 
(only in EPP or higher versions). Therefore, instead of forced cooling, the power levels 
are  lowered  when  temperature  is  too  high.  One  expert  interview  revealed  that  Qi2 
specifications include more efficient heat management, but still do not require active 
cooling like a fan.  

In contrast, some proprietary chargers with higher power levels need cooling to avoid 
overheating and extensive power loss through heat dissipation. Thus, forced cooling 
techniques are more likely to be observable with proprietary chargers.  

Interoperability and communication protocols of different chargers 

Combining different chargers and devices can be limited by different frequency ranges 
and  communication  protocols  they  use.  E.g.,  the  Qi  standard  uses  in-band 
communication  with  data  transmission  happening  on  the  same  frequency  band  as 
wireless charging. The protocol controls the power output level and duration according 

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to  the  power  demand  of  the  device  (Figure  15)  and  authentication  as  secondary 
purpose (WPC, 2021b).  

Communication  begins  when  a  transmitter  senses  proximity  of  a  receiver.  The 
Baseline  Protocol  of  the  BPP  (3.2.3.)  comes  with  unidirectional  communication 
(transmitter  to  receiver),  while  the  Extended  Protocol  of  the  EPP  is  capable  of  bi-
directional communication with the receiver sending data back to the transmitter. This 
enables power transmission adjusted to the demand of the receiver. By default, power 
transfer is initiated according to the Baseline Protocol, with fix values during the whole 
transfer  (e.g.  5W  as  guaranteed  load  power).  In  the  EPP,  the  Power  Transfer 
Contract31 between transmitter and receiver can be negotiated: If the transmitter gets 
appropriate signals from the receiver, capabilities of the EPP are enabled, e.g. higher 
power levels (up to 15 W). However, the Negotiable Load Power (the highest load the 
transmitter is „willing” to negotiate) can be lower than the Potential Load Power,32 e.g. 
in cases of overheating risk due to high operating temperature or a less capable power 
supply. Factors which influence the Load Power33 level supported by a transmitter are 
the following: 

•  Designs of transmitter and receiver, 

•  Position of receiver in the Operating Volume 

•  Power supply of the transmitter 

•  Load of the receiver 

•  Operating temperature. 

The transmitter and receiver continuously keep track of any changes of the elements 
of the Power Transfer Contract and renegotiate accordingly. (WPC, 2021b.) 

31 Power Transfer Contract is the term defined in the Qi specifications for a collection of settings and 

limits governing a power transfer. (WPC, 2021c) 

32 Potential Load Power: A term defined in the Qi specifications for the highest Guaranteed Load Power 
level the power transmitter can negotiate. Guaranteed Load Power is a Load Power level agreed 
between the power receiver and the power transmitter. (WPC, 2021c) 

33 Load power: A term defined in the Qi specifications as the power dissipated in the load (which is a 

subsystem drawing power from a receiver), (WPC, 2021c) 

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Figure 16 – Qi communication protocol process 

Source: KPMG, 2024 based on Lu et al., 2016; WPC, 2021b 

According  to  the  above,  a  basic  interoperability  concerning  smartphone  charging  is 
established  at  5W  power  limit  through  the  baseline  protocol,  independent  on  the 
special designs of the receiver and the transmitter. This means that even proprietary 
(inductive) chargers will charge a device suitable for inductive charging (e.g. a phone), 
but only at the baseline protocol level (≤5W). Higher power levels can only be reached 
if the appropriate communication between transmitter and receiver can be established, 
meaning that both the transmitter and the receiver support at least the EPP of the Qi 
standard.  

Another  interoperability  aspect  is  the  operating  frequency.  For  instance,  Qi2  is 
capable of a higher frequency with better transfer efficiency, but in order to enable this 
frequency band, it checks the version of the receiver. Until there is no sign that the 
receiver  is  capable  of  Qi2’s  higher  frequency,  it  is  not  activated  but  kept  at  basic 
frequency levels of former Qi version.  

Interoperability  issues  from  different  frequency  bands  are  mentioned  in  a  proof-of-
concept experimental design by Hwang et al. in 2016, who set up an all-in-one wireless 
charger for wearables supporting the Qi, PMA and A4WP standards. A4WP using a 
much higher frequency (6.78 MHz) than Qi and PMA (100-300 kHz) gets close to the 
13.56  MHz  ISM  band  used  by  the  NFC  chips  in  mobile  phones,  which  could  suffer 
permanent  damage  from  receiving  excessive  energy  by  the  A4WP  transmitter 
antenna. The all-in-one solution therefore included an NFC Protection circuit (Hwang 
et al., 2016). This example is cited only to highlight the role of frequency at this point, 
but otherwise not relevant to the findings of the present Study as no marketed products 
supporting the A4WP and PMA standards have been found for consumer electronics.  

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6.2.  Experiment 

In  order  to  have  practical  information  on  energy  efficiency,  charging  performance 
charging time, heating and interoperability, a measurement experiment was conducted 
with a selection of wireless chargers and wireless charging capable devices. Beyond 
the  verification  of  the  findings  of  Technical  Overview  (section  6.1.)  and  Voice  of 
Customer (section 4.3.) analysis, the experiment could also be beneficial to point out 
the potential impacts of future developments on the market, for instance from charging 
performance point of view. 

Based  on  the  findings  of  Technical  Overview  (section  6.1.)  and  Product  Overview 
(section  5.),  only  inductive  technologies  were  included  in  the  experiment  ,  more 
concretely  Qi  (or  Qi  +  proprietary)  solutions.  Although,  the  scope  of  the  experiment 
could  not  be  considered  representative  and  the  accuracy  of  the  findings  could  be 
further elaborated by including additional products in the test, it could underline the key 
differences between existing technologies and interoperability issues on the market. 

6.2.1.  Technical structure of the experiment 

The  wireless  charging  experiment,  as  illustrated  in  Figure  16,  involves  a  structured 
method for measurement and analysis.  

It is important to acknowledge that energy loss occurs at different stages of the wireless 
charging  system.  However,  compared  to  wired  charging,  only  the  power  transfer 
between transmitter and receiver generates additional energy loss (for further detailes 
please refer to section 6.1). Therefore, given the scope of the study, the focus was on 
examining power flow between the transmitter and receiver.  

In order to measure the charging performance between the transmitter and receiver, 
both the input and output sides had to be examined. To this end, for the input side, a 
USB C power tester, namely the KWS-1902C-USB Power Meter (further referred as 
Power  Meter),  was  connected  to  the  output  of  the  EPS  and  the  input  of  transmitter 
using short, low-resistance USB Type-C charging cables. The power meter ensured 
accurate measurement, thanks to its capacity to measure relatively small units, thus 
improving the accuracy of the test and also enabling the measurement of standby loss. 
This  setup  not  only  facilitated  precise  measurement  of  voltage  (V),  current  (A), 
provided energy  (mAh)  and  power  (W)  but  also  ensured  minimal  energy  loss  within 
this section of the charging system. 

Regarding the output side, specialised applications were used to measure absorbed 
energy of the devices. Those applications were AIDA64 and Amperes (lite), and their 
usage were contingent upon the operating system possessed by the respective device. 
The  applications  are  able  to  measure  numerous  data  at  battery  such  as  voltage  or 
temperature (for further details please refer to section 6.2.3) However, it is crucial to 
note that there are cases where it was not possible to load that software onto certain 
devices, particularly to low-power electronics. In cases where software installation was 

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not feasible, manual measurement method was employed, which entail observing the 
device's charging compatibility with various transmitters.34 See 6.2.2. 

The  conducted  experiment  allows  for  a  comprehensive  evaluation  of  charging 
performance  and  energy  efficiency,  by  the  comparison  of  energy  used  and  energy 
absorbed. Therefore, it could contribute to the present Study’s findings with valuable 
insights regarding the system's performance. 

Figure 17 – Schematic technical structure of the experiment 

Source: KPMG, 2024 

6.2.2.  Device and transmitter selection 

To  ensure  the  experiment's  accuracy,  a  diverse  set  of  products  from  multiple 
manufacturers was chosen, aiming to encompass most important sectors or product 
categories.  As  a  general  principle,  the  selected  products  were  new  or  barely  used 
devices  and  chargers,  which  further  support  the  accuracy  of  the  experiment. 
Nonetheless, all products are anonymised, without reference to specific brand names, 
to guarantee the objectivity of the present Study. 

In  pursuit  of  methodological  robustness,  the  present  Study  endeavoured  to  ensure 
diversity  within  each  selected  product  category,  where  applicable.  Products differed 
not only in their brands but also in technical parameters such as maximum power level. 
This  methodological  approach  facilitated  the  thorough  examination  of  numerous 
scenarios, thereby enabling the identification of multiple interrelations. Therefore, the 
selected products by product categories for the experiment were as follows: 

●  EPS. EPSs were selected to optimise the performance of Transmitters used in 
the experiment and ensure comparability of the results. Two types of EPS were 
used during the  test, both featuring a USB output connection and capable of 
adjusting  output  voltages  and  currents  across  a  wide  range,  while  also 
supporting fast and super-fast charging. The first EPS was a 25W model, while 
the second was a 55W model recommended for the 50W wireless charger also 

34  Energy  losses  between  EPS  -  Power  Meter,  Power  Meter  -  Tx,  and  Rx-Device  were  considered 
negligible.  Additionally,  measuring  the  loss  between  the  Rx-Device  would  involve  additional 
complexities as disassembling the device for measurement purposes could increase inaccuracies. 
Consequently, these negligible losses were excluded, and focus were maintained on the energy 
transfer between the transmitter and the receiver within the experimental framework. 

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utilised in the experiment. The 25W EPS model was used during all scenarios 
that excluded the 50W wireless charger (EPS used with transmitters A, C, and 
D), while the 55W EPS model was used in the remaining scenarios (EPS used 
with transmitter B). 

●  Transmitters. Four transmitters were selected for the experiment with USB-C 
connection. Three out of four had Qi certification and minimum 15W potential 
output  power  level  (Transmitter  A,  B,  C).  One  branded  transmitter  had  50W 
potential  output  power  level  (Transmitter  B),  while  the  fourth  not  certified 
transmitter  had  10W  potential  output  power  level  (Transmitter  D).  With  the 
selected transmitters, it could be assessed whether significant distinctions exist 
between premium and non-premium chargers concerning for instance charging 
performance  and  energy  efficiency.  Furthermore,  the  impact  of  higher  output 
power level could be also investigated. 

●  Smartphone devices. Four smartphones were chosen for the experiment from 
leading  manufacturers  in  the  industry.  Smartphone  devices  were  selected  to 
align with the brands of transmitters selected. Among these, three were either 
new or barely used (Smartphone A, B, C1). The fourth smartphone was a used 
device (Smartphone C2), from the same brand as one of the aforementioned 
three (Smartphone C1), with slightly smaller physical size, smaller screen size 
and lower battery capacity. Similarly to transmitters, the smartphones selected 
could  enable  to  identify  whether  substantial  differences  exists  between 
smartphones with different input power level. 

●  Other  devices.  In  order  to  assess  interoperability  of  other  devices,  three 
smartwatches and one earbud from leading manufacturers were also included 
in the test. Despite the absence of data collection methods similar to those used 
for smartphones, the conducted test offers valuable insights into market issues 
regarding to interoperability. 

The  summary  of  selected  products  by  product  categories  for  the  experiment  are 
highlighted in Table 21: 

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Table 21 – Products used for the experiment  

EPS 

Transmitters 

Smartphone devices 

Other Devices 

−  Smartwatch A  
−  Smartwatch C1 
−  Smartwatch C2  
−  Earbud E 

−  EPS C: 

25W EPS 

−  EPS B: 

55W EPS 

−  Transmitter A: branded, 
15W output power level, 
recommended for 
Smartphone A 

−  Transmitter B: branded, 
15W output power level, 
recommended for 
Smartphone B 

−  Transmitter C: branded, 
50W output power level, 
recommended for 
Smartphone C 

−  Transmitter D: branded, 
not certified Qi charger, 
10W output power level 

−  Smartphone A: 
15W input power 
level 

−  Smartphone B: 
50W input power 
level 

−  Smartphone C1: 
15W input power 
level 

−  Smartphone C2: 

Used, lite version of 
Smartphone C1 

Source: KPMG, 2024 

Throughout the Study, when referring to products by their identifiers (e.g., "Transmitter 
A" and "Smartphone A"), the letter indicates products from the same brand. In other 
words, for instance, both Transmitter B and Smarphone B are from brand B. 

6.2.3.  Data collection 

Combination of devices and transmitters analysed 

As  per  detailed  above,  the  investigation  encompassed  four  different  chargers,  each 
with  distinct  specifications,  four  smartphones,  three  different  smartwatches  and  one 
earbud.  Additionally,  since  alignment  testing  was  a  crucial  aspect  of  assessing  the 
performance and efficiency of wireless charging systems, a misalignment experiment 
was  conducted  with  one  of  the  aforementioned  smartphones  to  evaluate  how 
positioning influences charging effectiveness.  

This  setup  entailed  a  total  of  20  different  configurations35  for  analysis,  including 
misalignment,  reflecting  the  extensive  data  to  be  gathered.  By  exploring  a  diverse 
range  of  setups,  the  aim  was  to  capture  nuanced  insights  into  wireless  charging 
performance,  ensuring  a  thorough  understanding  of  its  practical  applications  and 
limitations.  Additionally,  to  ensure  comprehensive  analysis  and  comparability,  wired 
charging alongside these setups were also measured. This inclusion further enhanced 
the  depth  of  the  present  Study,  allowing  for  a  comprehensive  evaluation  of  both 
wireless and wired charging methods and their respective performance characteristics. 

35 by multiplying the number of wireless chargers with the number of smartphones and one misalignment 

scenario [4 x (4+1) = 20] 

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Recorded variables 

The collected data were systematically organised into a table format, encompassing 
both the input (transmitter) side and the output (device) side. During the data collection 
process, detailed information was recorded for each device at various charge levels 
(25%, 50%, 75%, and 99%). Distinct recording of variables was necessary as the value 
of  specific  data  dynamically  changed  over  time,  illustrating  the  evolving  state  of 
charging and its efficiency. The last recorded charging level was set at 99% because 
the charging process practically  stops at 100% and the transmitter  only replenishes 
the energy consumed while the device is turned on. Additionally, it has no impact on 
the value of calculated variables (e.g.: energy efficiency).  

During the test, data was collected for all (20) scenarios assessed, encompassing both 
aligned  and  misaligned  scenarios.  A  comprehensive  list  of  recorded  and  calculated 
variables is presented in Table 22. 

Table 22 – Recorded and calculated variables 

Recorded variables 

Input (transmitter) side 

Output (device) side 

−  Input voltage (V) 
−  Current (A) 
−  Provided energy (mWh)  
−  Charging time (minutes) 

−  Temperature (°C) 

−  Output voltage (V) 
−  Charging rate (mA) 
−  Charge counter (mAh) 
−  Capacity measured (mAh) 
−  Battery voltage (V) 

Calculated variables 

−  Provided power (W) 

calculated by multiplying the 
Input voltage (V) with the 
Charging rate (A) 
−  Charging power (W) 

calculated by multiplying the 
Output voltage (V) with the 
Charging rate (A) 
−  Power efficiency (%) 

calculated by dividing the 
Charging power (W) with the 
Provided power (W) 

−  Power loss (%) calculated 
by subtracting Power 
efficiency (%) from 1 
−  Power loss (W) calculated 
by multiplying the Power 
loss (%) with the Provided 
power (W) 

−  Stored energy (mWh) 

calculated by multiplying the 
Battery Voltage (V) with the 
Capacity measured (mAh) 

−  Energy efficiency (%) 

calculated by dividing the 
Stored energy (mWh) with 
the Provided energy (mWh) 

Source: KPMG, 2024 

Based on the measured voltage and amperage variables, both the provided power and 
charging  power  level  were  calculated.  These  calculated  variables  were  essential  to 
quantify  power  efficiency  and  other  power  related  variables  like  power  loss. 

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Furthermore, overall energy efficiency was assessed by the utilisation of the provided 
energy and stored energy which was quantified by battery capacity and voltage. These 
measurements provided valuable data on how efficiently energy is transferred from the 
transmitter to the receiver on what power level, shedding light on the effectiveness of 
the wireless charging technology employed. 

Moreover, analyses of other variables such as temperature and charging time provided 
insights  for  the  user  experience  aspects  of  wireless  charging  systems.  Overheated 
devices were one of the most common feedbacks on wireless charging based on the 
collected and reviewed customer feedbacks, while prolonged charging time was also 
identified as a key factor affecting market growth.  

In  the  data  gathering  process,  measurements  were  initially  obtained  through  the 
applications used. When specific data points, such as battery capacity, could not be 
directly  measured,  reliance  was  placed  on  information  sourced  from  product 
descriptions provided by manufacturers. If the factory data appeared reliable, it was 
integrated into the analysis. However, there was a case where factory data proved to 
be unrealistic, adjustments were made accordingly. Such modification was required for 
Smartphone B’s battery capacity, as the calculated energy efficiency based on factory 
battery capacity was exceeding 100%. Therefore, its battery capacity was calculated 
assuming  the  best  energy  efficiency  measured  with  wired  charging  (96%)  was  also 
achieved by Smartphone B through wired source. If neither measured nor factory data 
were  available,  it  was  omitted  from  the  examination.  This  was  necessary  due  to 
technical  limitations  of  the  application  used  and  the  operating  system  in  case  of 
Smartphone A where certain variables (such as temperature, charge rate, etc.) could 
not  be  recorded.  Nevertheless,  throughout  the  analysis,  conclusions  were  drawn 
based solely on data recorded and adjustments were highlighted consistently. 

Regarding energy efficiency, the charging period between 25% and 75% charging level 
was also examined. The calculation process involved dividing the aggregated stored 
energy (derived from battery capacity) by 2, as the 25-75% range represents half of 
the full capacity. Subsequently, this result was divided by the difference between the 
provided energy at 75% and at 25%. The results revealed no discernible disparity in 
energy efficiency between the 25-75% charging interval and the full 0-99% range. In 
the  present  Study,  energy  efficiency  is  presented  related  to  the  0-99%  charging 
interval. 

In  conclusion,  this  comprehensive  dataset  provided  insights  for  the  charging 
performance  and  efficiency  of  different  variations  observed,  while  also  offering  a 
nuanced perspective on the interplay between energy efficiency, alignment, and the 
overall performance of wireless charging systems. 

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6.2.4.  Results 

6.2.4.1. 

Interoperability of products used in the experiment 

In order to assess the interoperability of products used in the experiment, all devices 
with all transmitters were subjected to charging tests to determine their compatibility. 
Throughout this subsection, emphasis was placed solely on the occurrence of charging 
between  devices  and  wireless  chargers,  without  considering  the  efficiency  or 
performance metrics. The aim was to investigate the extent to which devices were able 
to engage in charging interactions with different wireless charging systems. The results 
of the interoperability test can be seen in Table 23. 

Table 23 – Result of interoperability test for scenarios examined 

Tick symbols indicate successful charging interactions, reflecting interoperability,  
while the absence of ticks signifies compatibility issues 

Transmitter A 

Transmitter B 

Transmitter C 

Transmitter D 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

✔ 

Smartphone A 

Smartphone B 

Smartphone C1 

Smartphone C2 

Smartwatch A  

Smartwatch B  

Smartwatch C  

Earbud A 

✔ 

✔ 

✔ 

✔ 

Source: KPMG. 

For smartphones, in all scenarios tested, including misaligned scenario, charging was 
successfully completed across various phone models and charging platforms. Notably, 
in instances of misalignment, it was observed that charging could still occur even when 
the alignment was not entirely accurate, depending on the specific combination and 
the margin of error involved. However, it is important to highlight that this workaround 
may lead to overheating issues based on empirical observations, potentially causing 
damage to the phone in extreme cases. 

For the earbud, it was found that charging successfully occurred between the earbud 
and all transmitters. However, it is important to note that while charging functionality 
was observed, practical usage may be hindered in certain cases due to the form factor 
of both the charger and the earbud charging case. For instance, in case of transmitter 
with vertical or tilted charging platform, aligning the coils to ensure proper charging is 
not possible in the original way of usage. Charging only takes place if the transmitter’s 

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charging platform is positioned horizontally, potentially impacting the proper usability 
of the charging setup for earbuds or similar low power electronics equipment. 

In  contrast  to  the  successful  interoperability  observed  with  smartphones  and  the 
earbud,  the  smartwatches  in  the  experiment  did  not  demonstrate  compatibility  with 
other  branded  chargers  tested,  even  if  they  were  ‘labeled’  Qi-enabled.  Each 
smartwatch exclusively functioned with its respective factory watch charger, failing to 
charge with chargers designed for smartphones. This limitation is likely attributed to 
the  size  of  the  watches  and  the  coils  within  them,  rendering  chargers  designed  for 
smartphones ineffective. Consequently, interoperability was not achieved in the case 
of watch chargers neither.  

Although the number of devices involved in the experiment was limited, the findings of 
the  interoperability  test  underline  the  findings  of  the  Product  Overview.  More 
concretely,  a  high  level  of  interoperability  could  be  assumed  in  the  case  of 
smartphones and earbuds as Qi (and Qi + Proprietary) solutions are dominant on the 
market.  On  the  other  hand,  less  interoperability  can  be  seen  among  smartwatches, 
even  in  the  case  of  Qi  certified  products.  Potentially,  the  form  factor  emerged  as  a 
critical factor, complicating efforts to standardise charging across all devices. Even if 
manufacturers start to introduce Qi standard in their smartwatches, the varying form 
factors of smartwatches may pose challenges for achieving universal compatibility.  

6.2.4.2.  Energy efficiency and charging performance of scenarios 

examined 

Aligned scenarios 

In  case  of  16  out  of  20  scenarios  examined,  smartphones  were  positioned  on  the 
transmitters in such a manner that they were aligned accurately with each other, in line 
with  usage  recommendation  in  the  product  sheets.  In  the  present  Study,  aligned 
scenarios refer to previously mentioned 16 scenarios examined. 

A fundamental relationship exists between charging time and average charging power, 
wherein a higher average charging power leads to a shorter charging time. The validity 
of this relationship was empirically confirmed through experimentation. The results are 
elucidated in Table 24 (except for Smartphone A for which charging power could not 
be  recorded  due  to  technical  limitations  of  the  applications  used).  This  principle 
underscores the direct impact of charging power on charging time and the importance 
of maximising charging power to expedite the charging process.  

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Table 24 – Average charging power and charging time36 

Transmitter 

Smartphone A 

Smartphone B 

Smartphone C1 

Smartphone C2 

Avg. 
charging 
power 
(W) 

Charging 
time 
(min) 

Avg. 
charging 
power 
(W) 

Charging 
time 
(min) 

Avg. 
charging 
power 
(W) 

Charging 
time 
(min) 

Avg. 
charging 
power 
(W) 

Charging 
time 
(min) 

Trans. A 

Trans. B 

Trans. C 

Trans. D 

Wired 

n/a 

n/a 

n/a 

n/a 

n/a 

164 

235 

137 

334 

77 

 2.7  

 12.1  

 2.8  

 3.1  

 17.1  

 272 

 70 

 275 

 243 

 59 

 4.2  

 3.2  

 9.3  

 2.7  

 15.5  

 239  

 292 

 115 

 304 

 75 

 3.9  

 3.3  

 7.3  

 3.1  

 11.3  

 223 

 232 

 117 

 229 

 79 

Source: KPMG based on experiment results 

Comparing  the  maximum  charging  power  between  wired  and  wireless  charging 
methods unveils distinctions that demonstrate the difference between wired, brand-to-
brand wireless and other wireless scenarios (Table 25). Both the maximum provided 
power by the EPS and the charging power at the battery were steadily higher for wired 
scenarios. Although, some instances, mostly brand-to-brand scenarios, stand out from 
wireless charging methods, the difference compared to the wired scenarios could be 
considered substantial.  

Table 25 – Provided power and charging power 

Power source 

Max. of provided power (W) 

Max. of charging power (W) 

SA 

SB 

SC1 

SC2 

Transmitter A 

Transmitter B 

 9.9  

 6.7  

 5.8  

 10.0 

 21.5  

 5.7  

 8.8  

 6.0 

Transmitter C 

 13.2  

 5.7  

 19.6  

 15.2  

Transmitter D 

Wired 

7.0 

 19.6  

5.5 

 30 

5.8 

5.9 

 21.5  

 20.3  

SA 

n/a 

n/a 

n/a 

n/a 

n/a 

SB 

3.2 

16.9 

3.2 

3.2 

 27.8  

SC1 

SC2 

 5.4  

 3.4  

11.6 

3.4 

 20 

 5.0 

 3.5  

 9.1  

3.6 

 18  

Note: SA, SB, SC1, SC2 abbreviations stand for Smartphone A, Smartphone B, etc. 

Source: KPMG. 

Results  consistently  demonstrated  that  the  provided  power  and  charging  power 
reached their peak when transmitters and smartphones were of the same brand. This 
setup  optimised  the  charging  process,  ensuring  efficient  power  transfer  and  faster 
charging  times.  Conversely,  in  scenarios  where  this  brand  match  was  absent,  both 
provided  power  and  charging  power  were  notably  degraded  potentially  due  to 
scenarios were operated with baseline protocols. On the other hand, consistent power 
efficiency levels between approximately 49% and 57% were observed across basically 

36 Data series could not be recorded for Smartphone A due to technical limitations of the applications 

used 

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all scenarios. This could indicate similar power efficiency level regardless of wireless 
charging  system  and  its  communication  protocol.  Nevertheless,  proprietary  solution 
between  Transmitter  B  and  Smartphone  B  exhibited  a  standout  power  efficiency  of 
71%, surpassing the typical range. On the other hand, this result was achieved with 
EPS  B  which  has  higher  power  level  (55W).  This  suggests  that  while  widely  used 
methods  generally  yield  consistent  power  efficiency,  proprietary  solutions  could 
demonstrate  the  potential  for  significantly  higher  efficiency  levels.  These  findings 
underscore  the  importance  of  brand  compatibility  and  communication  protocols  in 
maximising charging efficiency and highlight the potential drawbacks of mismatched 
transmitter and smartphone pairings in wireless charging setups.  

Upon analysing the charging time and energy efficiency in the conducted experiment 
(Table 26), the assessment confirmed several statements. Firstly, wireless charging 
systems are failing to meet the performance of wired charging both in terms of energy 
efficiency and charging time point of view which is in line with the findings of Technical 
Overview. Secondly, there is no discernible correlation between energy efficiency and 
charging time in case of wireless charging systems examined. Faster charging time 
did not necessarily equate to higher energy efficiency, nor did optimal energy efficiency 
guarantee swift charging.  

Table 26 – Charging time of scenarios tested 

Power source 

Charging time 0-99% (min) 

Transmitter A 

Transmitter B 

Transmitter C 

Transmitter D 

Wired 

Source: KPMG 

Smartphone A 

Smartphone B 

Smartphone C 

Smartphone D 

 164  

 235  

 137  

 334  

 77  

 272  

 70  

 275  

 243  

 59  

 239  

 292  

 115  

 304  

 75  

 223  

 232  

 117  

 229  

 79  

Table 27 – Energy efficiency of scenarios tested 

Power source 

Energy efficiency (%) 

Transmitter A 

Transmitter B 

Transmitter C 

Transmitter D 

Wired 

Source: KPMG 

Smartphone A 

Smartphone B 

Smartphone C 

Smartphone D 

60% 

52% 

46% 

44% 

82% 

66% 

77% 

70% 

79% 

96% 

59% 

69% 

57% 

64% 

87% 

59% 

70% 

62% 

72% 

96% 

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These  observations  highlight  the  intricacies  within  wireless  charging  dynamics, 
illustrating that while there is an active development on the field of wireless charging 
technologies,  achieving  a  solution  that  balances  both  quick  and  efficient  charging 
remains a challenge, or at least not yet widely adopted in the consumer electronics 
market. The findings suggest a need for continued research and innovation in the field, 
prompting a re-examination in the future to assess how advancements may influence 
charging capabilities and overall user experience. 

In  the  smartphone  experiment,  it  was  observed  that  all  transmitters  exhibited  top 
performance (within the best two), either in terms of energy efficiency or charging time 
when paired with devices from the same brand. (For instance, Smartphone C1 had the 
fastest charging time with Transmitter C. On the other hand, this pairing had the lowest 
energy  efficiency  with  57%.  Additionally,  Smartphone  A  had  the  highest  energy 
efficiency  with  Transmitter  A,  while  Smartphone  A  had  the  second  fastest  charging 
time with the same transmitter.) This could highlight that there are notable differences 
among scenarios examined in terms of charging time and energy efficiency. Hence, 
despite the compatibility of smartphones and transmitters, customers could experience 
substantial gaps in the products’ performance. For instance, there were more than two 
hour  difference  in  total  charging  time  in  case  of  Smartphone  A  and  Smartphone  B 
charged by Transmitter C.  

Additionally,  also  the  potential  influence  of  development  priorities  beyond  mere 
compatibility could be assumed. This could be supported by the notable exception that 
arose  with  the  Transmitter  C,  where  emphasis  seemed  to  be  placed  on  enhancing 
charging time rather than prioritising energy efficiency. The fastest charging time with 
three  out  of  four  smartphones  with  the  lowest  or  second  lowest  level  of  energy 
efficiency was achieved with Transmitter C. This means that Transmitter C delivered 
the  best  result  from  charging  time  point  of  view  when  there  was  no  brand-to-brand 
match  (Smarphone  A).  This  divergence  suggests  differing  strategic  focuses  among 
manufacturers.  

In  the  context  of  the  smartphone  experiment,  Transmitter  B's  and  Smartphone  B’s 
proprietary solution must be highlighted as it delivered remarkable outcomes. Notably, 
when those two products paired with each other, exceptionally high energy efficiency 
was achieved alongside remarkably short charging times (77%37 energy efficiency, and 
70 minutes charging time) with outstanding power efficiency (71%) compared to other 
wireless  charging  scenarios.  Moreover,  it  is  noteworthy  that  the  disparity  between 
wireless  and  wired  charging  times  in  this  scenario  was  only  19%  (or  11  minutes) 
contrary  to  other  pairings  where  differences  were  at  least  ~50%  (Figure  17).  This 
suggests a notable convergence between wireless and wired charging efficiencies in 
the case of proprietary solution used by Transmitter B and Smartphone B, highlighting 
potential  advancements  in  wireless  charging  technology.  On  the  other  hand,  this 
proprietary solution’s energy efficiency, similarly to all other scenarios, did not exceed 

37 Calculated with estimated battery capacity derived from assumed 96% wired energy efficiency. 

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Study on wireless charging technologies 

the 80% theoretical limit highlighted at the technical overview on energy efficiency in 
section 6.2.1. 

Figure 18 – Wired and wireless charging time comparison 

Source: KPMG. 

Consequently,  in  contemplating  potential  standardisation  efforts,  a  critical  decision 
must be made regarding the desired direction: whether to prioritise energy-efficiency 
or faster charging becomes pivotal, underscoring the need for clarity in aligning future 
development trajectories. 

Additionally, to provide a holistic assessment of overall charging efficiency, the present 
Study introduced the KPMG-Gutti Wireless Charging Efficiency Index. The Index 
serves as a comprehensive metric for evaluating and ranking various wireless charging 
scenarios  in  comparison  to  their  wired  counterparts.  Its  purpose  lies  in  providing 
standardised means to assess the performance of different wireless charging setups 
across two critical dimensions: charging time and energy efficiency, relative to wired 
charging alternatives. Recognising the equal importance of both variables, the index is 
calculated by multiplying the relative charging time by the relative energy efficiency. 
This  approach  ensures  that  each  factor  contributes  proportionally  to  the  final  index 
score, reflecting their combined impact on charging performance. It is crucial to note 
the  methodological  choice  of  multiplication  over  addition  in  combining  the  two 
variables. This decision stems from the assumption that improvements in one aspect 
(e.g., a slight reduction in charging time) do not fully offset improvements in the other 
(e.g., energy efficiency gains). Thus, by multiplying, the index reflects the concurrent 
optimisation  of  both  charging  time  and  energy  efficiency,  without  treating  them  as 
substitutes for each other. 

Charging time, a pivotal aspect of user experience, is quantified by relative charging 
time  which  is  derived  from  the  relative  difference  between  the  wireless  charging 
duration and the corresponding wired charging time for a given scenario. To establish 
this comparison, the corresponding wired charging duration is divided by charging time 
of  a  device  using  wireless  charging  technology.  For  instance,  for  the  scenario  with 
Transmitter A and Smartphone A, Smartphone A’s wired charging time (77 minutes) is 
divided by Smartphone A’s wireless charging time with Transmitter A (137 minutes). 

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Study on wireless charging technologies 

The greater the value, the closer the charging time to the corresponding wired charging 
time.  Therefore,  this  value  indicates  how  far  the  wireless  charging  is  from  the 
performance of wired charging from charging time point of view. Additionally, by not 
using  either  the  best  nor  the  average  wired  charging  time,  the  Index  handles  the 
difference in used EPSs in wired charging (25W vs. 55W EPSs). 

Energy  efficiency,  another  crucial  factor,  is  quantified  by  the  relative  energy 
efficiency of the wireless charging scenario compared to its wired counterpart. Energy 
efficiency of given scenarios is calculated based on the provided and stored energy 
described in Data Collection section (6.2.3). By dividing the energy efficiency of the 
wireless  charging  scenario  by  that  of  its  wired  alternative,  the  index  assesses  how 
closely the wireless setup matches the efficiency of wired charging. A higher resulting 
value indicates greater parity with wired charging efficiency. 

Notably, the Index’s maximum value is set to 1, representing parity with wired charging 
efficiency  from  energy  and  charging  time  point  of  view.  This  ensures  that  wireless 
charging  solutions  are  evaluated  relative  to  the  established  benchmark  of  their 
corresponding  wired  charging.  In  other  words,  if  a  wireless  charging  solution  is 
able  to  achieve  1  for  the  KPMG-Gutti  Wireless  Charging  Efficiency  Index,  it 
means that  the  given wireless charging method is  equally efficient  as a wired 
charging. 

128 

Study on wireless charging technologies 

Figure 19 – KPMG-Gutti Wireless Charging Efficiency Index 

Source: KPMG. 

As it can be seen on Figure 18, brand-to-brand scenarios were the top performer based 
on their Index score. Additionally, the proprietary solution of Transmitter B stands out 
from  all  scenarios  considering  this  comprehensive  metric  as  well  (more  than  50% 
higher score than the second best). Although, there were  other scenarios that were 
close to brand-to-brand scenarios, such as Transmitter C with Smartphone A which 
has 0,02 point less score than Transmitter A with Smartphone A, it can be seen that 
those scenarios without brand arrangement have ~50% lower score on average. The 
findings based on the Index further support that there are exisiting differences between 
scenarios  and  brand  arrangement  had  substantial  impact  on  overall  charging 
performance.  Additionally,  potential  of  proprietary  solutions  was  underscored  by the 
Index as well. 

Misaligned scenario 

In case of 4 out of 20 scenarios examined, Smartphone C2 were positioned on the four 
transmitters included in the experiment in such a manner that Smartphone C2 was not 
aligned accurately on the trasmitters. The smartphone was positioned to the edge of 

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Study on wireless charging technologies 

the charging surface, where continuous charging still took place. In the present Study, 
misaligned scenarios refer to previously mentioned 4 scenarios examined. 

In the misalignment experiment, aligned and misaligned scenarios were compared to 
assess their impact on charging time, energy efficiency, and other variables recorded. 
Although, introduction of Qi2 could improve alignment and energy efficiency (as it was 
stated in section 3.2), measurement of average input power and charging power could 
provide  insights  on  charging  behaviour  under  misaligned  conditions  (Table  27).  In 
misalignment  scenarios  during  wireless  charging, 
the  behaviour  of  charging 
transmitters  plays  a  pivotal  role  in  the  performance  of  wireless  charging  system. 
Notably, in scenarios where charging time remained unchanged despite misalignment 
(such as with Transmitters B and D), it appeared that the charging process commenced 
at  a  higher  provided  power  level,  presumably  due  to  the  transmitter  sensing  an 
imperfect fit. This approach ensures that the charging time remains unaffected by the 
deviation in alignment. 

Table 28 – Average input power and average charging power 

Aligned versus misaligned scenarios used for Smartphone C2 

Transmitter 

Average provided power 
(W) 

Average charging power 
(W) 

Charging time  
(min) 

Aligned 

Misaligned 

Aligned 

Misaligned 

Aligned 

Misaligned 

Transmitter 
A38 

Transmitter B 

Transmitter C 

Transmitter D 

Source: KPMG. 

7.9 

5.9 

13.0 

5.8 

n/a 

9.4 

8.2 

8.7 

3.9 

3.3 

7.3 

3.1 

n/a 

3.2 

3.2 

3.4 

223 

232 

117 

229 

n/a 

230 

249 

227 

Conversely,  Transmitter  C  potentially  opt  to  reduce  input  power  when  faced  with 
misalignment,  leading  to  a  decrease  in  charging  power  and  subsequently,  reduced 
power  efficiency.  These  contrasting  behaviours  highlight  the  diverse  strategies 
adopted by wireless chargers in response to misalignment situations. Some prioritise 
maintaining charging power levels to uphold efficiency and charging time, while others 
prioritise  minimising  performance  to  ensure  the  most  efficient  use  of  available 
resources.  Understanding  these  behaviour  preferences  of  chargers  is  essential  in 
optimising  wireless  charging  systems  for  various  usage  scenarios  and  user 
preferences.  

Regarding the charging time and energy efficiency of misaligned scenarios, multiple 
statements could be concluded. In line with the highlights of the technical overview in 
section 6.2.1,  energy efficiency took a significant hit in the misalignment conditions, 
due  to  the  potentially  lower  coupling  coefficient.  More  concretely,  misaligned 

38 The misaligned experiment was canceled before 50% of charging because of overheating. 

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Study on wireless charging technologies 

scenarios  were  performed  with  energy  efficiency  levels  9  to  23  percentage 
points lower. 

On  the  other  hand,  surprisingly,  only  the  misaligned  scenario  with  transmitter  C, 
experienced  an  increase  in  charging  time,  while  with  Transmitter  D  and  with 
Transmitter B misalignment had basically no impact on charging time compared to the 
aligned scenario, potentially due to the same average charging power level.  

Table 29 – Comparison of wireless chargers 

Aligned versus misaligned scenarios used for Smartphone C2 

Transmitter 

Energy efficiency (%) 

Charging time 0-99% (min) 

Transmitter A39 

Transmitter B 

Transmitter C 

Transmitter D 

Source: KPMG. 

Aligned 

Misaligned 

Aligned 

Misaligned 

59% 

70% 

62% 

72% 

39% 

47% 

46% 

63% 

223 

232 

117 

229 

- 

230 

249 

227 

During the experiment, Transmitter A and the tested device experienced overheating 
issues, leading to the suspension of the experiment before reaching 50% charging due 
to safety concerns arising from temperatures exceeding a certain threshold. Despite 
the  suspension,  the  calculated  energy  efficiency  remained  lower  than  the  aligned 
scenario. Before its cancellation, the results were adverse, with the 0-25% charging 
phase  taking  90  minutes  (compared  to  the  42  minutes  in  the  aligned  scenario)  and 
experiencing a 20% points drop in energy efficiency (for further details on temperature, 
please refer to section 6.2.4.3).  

Examining  the  KPMG-Gutti  Index  values  of  the  tested  misaligned  scenarios  also 
reveals that the  misalignment negatively impacts charging performance (Figure  19). 
This is accounted to the substantial decrease in energy efficiency due to misalignment. 
Transmitter  B  and  Transmitter  C  with  Smartphone  C2  exhibited  the  lowest  relative 
energy  efficiency  compared  to  wired  charging  across  all  tested  wireless  scenarios. 
Transmitter  D  with  Smartphone  C2  resulted  in  the  highest  KPMG-Gutti  Index  score 
among misaligned scenarios, but its score remained lower than its aligned counterpart 
by 0,03 point. In overall, while some misaligned scenarios outperformed certain aligned 
setups (such as Transmitter D with Smartphone A or Transmitter A with Smartpone B), 
all  misaligned  scenarios  have  not  reached  0,24  index  score.  This  highlights  the 
challenges of efficiency and speed in wireless charging, especially when alignment is 
compromised. 

39  The  misaligned  experiment  was  canceled  before  50%  of  charging  because  of  overwarming. 

Therefore, the misaligned cells only contain data measured at a 25% charge level. 

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Study on wireless charging technologies 

Figure 20 – KPMG-Gutti Wireless Charging Efficiency Index 

including misaligned scenarios 

Source: KPMG. 

Standby loss 

In  assessing  the  standby  loss  of  wireless  charging  transmitters,  the  four  tested 
chargers  were  measured  in  standby  mode  (standby  mode  refers  to  state  in  which 
transmitter is powered on and ready to charge, without electronic device in charge on 
them)  to  calculate  their  daily  energy  consumption.  To  ensure  comparability, 
Smartphone  C2  was  selected  as  the  reference  device  for  both  wireless  and  wired 
scenarios. The percentage of standby energy loss equivalent to the energy required to 
charge Smartphone C2 (with Transmitter C or wired) was determined and highlighted 
in Table 29. 

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Study on wireless charging technologies 

Table 30 – Standby loss for transmitters 

compared to other scenarios 0-99% energy requirements 

Transmitter 

Standby loss in 24 
hours (mWh) 

Transmitter A 

Transmitter B 

Transmitter C 

Transmitter D 

Source: KPMG. 

10 000 

     580 

  5 316 

  9 951 

For Smartphone C2 

With Transmitter C, the 
measured standby loss in 
24 hours equals a charge 
from 0% to… 

With wired charging, the 
measured standby loss in 24 
hours equals a charge from 0% 
to… 

38% 

2% 

20% 

38% 

59% 

3% 

32% 

59% 

Results revealed similarities and disparities among the transmitters. Transmitter A and 
D have the biggest amount of stand by loss. More concretely, Transmitter A and D 
consume as much as energy through 24 hours in standby mode that would be 
enough to charge Smartphone C2 from 0 to 38% with Transmitter C wirelessly 
and to 59% with wired charging. Those numbers were comparatively better, but also 
substantial case of Transmitter C, as it demonstrated 20% for wireless charging and 
32%  for  wired  charging,  the  observed  level  of  standby  loss  in  these  transmitters,  is 
relatively high, indicating inefficient energy management.  

Such  a  substantial  standby  loss  is  unfavourable  as  it  contributes  to  unnecessary 
energy consumption, leading to increased environmental impact. The results for those 
transmitters  are  in  line  with  the  highlights  of  the  technical  overview  on  energy 
efficiency. More concretely, cutting the standby loss by half could result in the same 
energy savings as the improvement of full-power efficiency with 10% (Perzow, 2022). 
Consequently,  reducing  standby  loss  is  imperative  for  improving  overall  energy 
efficiency and minimising wastage in wireless charging systems. 

Conversely, Transmitter B emerged as the most efficient option in terms of stand by 
loss,  with  2%  for  wireless  charging  and  3%  for  wired  charging,  indicating  superior 
performance  in  minimising  energy  waste.  Considering  that  the  proprietary  solution 
utilised by Transmitter B also demonstrated the best results in terms of charging time, 
power efficiency and energy efficiency, the overall performance of this solution stands 
out among the other scenarios tested. It also offers insights for a potential improvement 
area to refine devices with a focus on minimising standby loss. Nevertheless, potential 
reasons for such difference in standby loss could be the difference in technology used 
or different release date of transmitters. Further investigation might be required to draw 
conclusion  as  the  transmitters  tested  cannot  be  considered  as  a  representative 
sample.  

Further development on this aspect could lead to reductions in energy consumption 
and  contribute  to  improved  sustainability  practices  within  the  industry.  Moreover, 
consumers may benefit from selecting chargers with lower standby losses to mitigate 
energy waste and reduce their environmental footprint. 

133 

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6.2.4.3.  Temperature 

The significance of temperature in wireless charging is underscored by its critical role 
in  customer  complaints,  as  highlighted  in  the  Voice  of  the  Customer  (Section  4.3), 
where  overheating  emerged  as  a  key  concern.  Thus,  our  experiment  aims  to 
investigate  overheating  issues  associated  with  wireless  charging.  Monitoring  and 
controlling  temperature  variations  during  wireless  charging  are  crucial  to  prevent 
overheating, which can degrade battery performance and longevity over time. In this 
experiment,  temperatures  were  measured  (via  the  application  used)  across  various 
scenarios, with the average temperatures recorded and compiled in Table 30. 

Table 31 – Average temperature during the charging process40  

Power source 

Average temperature (°C) 

Transmitter A 

Transmitter B 

Transmitter C 

Transmitter D 

Wired 

Source: KPMG 

Smartphone B 

Smartphone C1 

Smartphone C2 

 33.3  

 39.0  

 30.0  

 30.8  

 36.3  

 39.4  

 31.0  

 36.5  

 32.9  

 31.1  

 41.3  

 34.8  

 37.5  

 35.1  

 32.8  

The  key  takeaways  from  the  experiment  reveal  intriguing  insights  regarding  to 
temperature of devices during wireless charging. Firstly, a notable trend was observed 
indicating  that  higher  average  temperatures  are  associated  with  wireless  charging 
when compared to wired charging methods. Moreover, this trend was consistent for 
brand-to-brand charging scenarios where the average temperatures were consistently 
higher  than  those  for  wired  connections.  This  supports  that  more heat  is  generated 
during the operation of wireless charging which is in line with the findings of technical 
overview on charging performance (section 6.1). More concretely, wireless charging 
typically results in higher average temperatures compared to wired methods. 

While  exceptions  to  this  observation  may  occur,  typically  arising  when  wireless 
charging is conducted at very low power levels and over substantially longer durations 
(for instance Smartphone B with Transmitter A, C and D), the general pattern remains. 
However,  it  is  noteworthy  that  achieving  lower  temperatures  required  sacrificing 
charging  speed  that  could  be  achieved  by  lower  charging  power.  This  trade-off 
highlights a key consideration in the design of wireless charging systems: balancing 
charging  efficiency  with  temperature  management  to  ensure  the  best  potential 
performance. 

40 Data series could not be recorded for Smartphone A due to technical limitations of the applications 

used 

134 

 
 
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Table 31 illustrates the comparison of how the position and alignment of the device 
impact the device’s temperature during wireless charging and how it is connected to 
wired charging. 

Table 32 – Average temperature in different scenarios 

for smartphone C2 

Device 

Average temperature (°C) 

Aligned scenario 

Transmitter A 

Transmitter B 

Transmitter C 

Transmitter D 

Average 

Smartphone C2 

41.3 

34.8 

37.5 

Smartphone C2 

43.441 

34.7 

33 

Misaligned scenario 

35 

35 

35.8 

36.5 

Smartphone C2 

Source: KPMG 

Wired charging 

32.8 

The  findings  from  the  experiment  reveal  notable  differences  in  device  temperature 
across different charging scenarios. Wired charging exhibited the lowest temperature, 
recording  at  32.8°C.  However,  the  aligned  and  misaligned  scenarios  yielded  mixed 
results.  Transmitter  C  demonstrated  lower,  while  Transmitter  B  and  D  maintained 
basically  the  same  temperatures  in  the  misaligned  setup  compared  to  the  aligned 
counterpart.  This  would  indicate  that  misalignment  has  no  impact  on  devices’ 
temperatures, but Transmitter A experienced a notable temperature increase from 40.9 
to  43.4°C  at  25%  charging  level  and  further  increase  beyond,  ultimately  leading  to 
suspension  due  to  overheating  concerns  before  reaching  50%  charging  level.  This 
indicates  that  there  may  be  cases  when  misalignment  could  cause  overheating,  as 
mentioned in section 6.1. 

The experiment's results underscore the multifaceted nature of overheating concerns 
during  wireless  charging.  On  the  one  hand,  charging  power  undoubtedly  could 
contribute to higher device temperature during wireless charging as the scenarios with 
the five highest charging power and the five highest temperatures were the same. On 
the other hand, the design of the wireless charging system could be equally critical in 
managing device temperature during wireless charging processes. The transmitter’s 
design can effectively dissipate heat generated during charging, thereby mitigating the 
risk of overheating. One key feature that enhances temperature management is the 
integration of a built-in cooling system within the transmitter. This cooling system helps 
to  regulate  temperature  by  dissipating  excess  heat  away  from  the  charging 
components,  ensuring  optimal  operating  conditions  for  both  the  transmitter  and  the 
device being charged (for further details please refer to section 6.1). 

41 The experiment was suspended before reaching 50% charging 

135 

 
 
 
 
 
Study on wireless charging technologies 

Within  the  experiment,  Transmitter  B,  C  and  D  had  an  in-built  cooling  system  while 
Transmitter  A  did  not  have  any  kind  of  feature  to  manage  temperature.  This  could 
contribute to the overheating issue in case of misalignment scenario with Transmitter 
A. Additionally, Transmitter A had the highest average temperature compared to other 
transmitters, further emphasising the importance of transmitter design. Therefore, the 
implications  of  such  a  cooling  system  are  important,  as  it  not  only  enhances  the 
reliability  of  wireless  charging  system  but  also  extends  the  lifespan  of  the  charging 
equipment  and  the  batteries  within  the  devices.  Nevertheless,  during  operation,  the 
integrated cooling system may produce a disturbingly loud noise for users 

These  findings  highlight  the  intricate  balance  between  temperature  management, 
charging  power  and  charging  speed  in  wireless  charging  systems,  emphasising  the 
need for careful optimisation to maximise both efficiency and user experience. 

136 

 
 
Study on wireless charging technologies 

7.  Conclusion 

The  emergence  of  wireless  charging  technologies  could  promise  an  age  of 
convenience  and  aesthetic  simplicity  for  recharging  electronic  devices  while  also 
narrowing  the  gap  between  the  energy  efficiency  of  wireless  and  wired  charging. 
However,  findings  of  the  present  Study  show  that  the  current  landscape  is 
characterised by ongoing developments, as present solutions still lack to fully or 
even partially serve customer needs and convenience. Therefore, further innovative 
effort  is  required  to  not  only  enhance  user  experience  but  also  to  maximise  energy 
efficiency in wireless charging systems.  

The technological landscape is characterised by fragmentation. There is no universal 
solution that caters to all devices uniformly, and specialists in the field are skeptical 
of  seeing  such  a  solution  arise  given  the  present  state  of  affairs.  So  far,  this  has 
fostered  a  natural  market  segmentation  based  on  the  physical  attributes  of 
devices. 

Key  findings  reveal  that  while  adoption  of  wireless  charging  in  products  is  still 
small  at  present,  there  is  a  steady,  ongoing  market  growth  fueled  by  consumer 
electronics, particularly smartphones. While the Qi standard dominates mobile phones, 
other consumer electronics lag behind mostly due to form factor constraints and the 
use of proprietary solutions. Wireless charging still faces substantial barriers, such as 
reduced energy efficiency, interoperability, charging speed, increased alignment 
issues, and environmental sustainability.  

In conclusion, these aspects should be considered regarding possible standardisation 
deliberations for the wireless charging market where experts unanimously agree that 
the technological and market development is still ongoing and is considered to be at 
its early stage. Therefore, currently identification of a potential harmonised charging 
solution  is  facing  challenges,  such  as  degree  of  market  acceptance,  charging 
performance  and  energy  efficiency.  Decisions  regarding  the  direction  of  potential 
standardisation,  whether  prioritising  energy  efficiency  or  rapid  charging  or  other 
aspects, will shape the future landscape of wireless charging technologies.  

137 

 
Study on wireless charging technologies 

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8.2. 

Annex I. – Indicative guide for stakeholder interviews 

Please note that the actual questions of the interview may vary depending on several 
factors. The guideline below is considered as an indicative pool of questions. 

Topics: 

1  Market Overview 

2  Market Landscape and Technologies 

3  Technological Developments 

4  The Voice of the Customer 

5  Standardization, Universality, and Efficiency 

1.  Market Overview 

a.  How has the market size changed compared to the findings of the previous 

study published in 2021?  

b.  Has the expected market growth occurred since 2021? Has the market growth 

been more or less significant than expected? Why? 

c.  How  would  you  describe  the  current  fragmentation  level  of  the  wireless 

charging sector compared to the situation in 2021? 

2.  Market Landscape and Technologies 

a.  What are the most popular technologies and standards for wireless chargers 

and wireless charging-capable devices on the market?  

b.  What do you consider as main reasons behind Qi dominating the wireless 

charging market nowadays? [Do you consider other standards beyond Qi for 
your products?] 

c.  Can a shift be anticipated regarding the above-mentioned matter?  

d.  Are there new technologies compared to those described in the 2021 study? 
Are there any technologies that have been driven out of the market since 
2021? 

e.  Can a "breakthrough" be identified that has the potential to radically change 

the market, or is it more of an incremental evolution of existing technologies? 

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3.  Technological Developments 

a.  What are differentiating features of the standard your organisation supports? 

b.  Which are the main factors when designing the external aspects (i.e. size 

and shape) of the charger/transmitter? [How do product measurements and 
intended use influence the choice of standards for your product?] 

c.  Is the technology your organisation supports capable of simultaneously 

charging several (different) devices? [Is this an important aspect for your 
product?] 

d.  Is interoperability considered in the design process? If so: 

—  Do your devices undergo any interoperability tests? If so, which 

parameters are used in those? 

—  Which are the main technical barriers and enablers found when 

designing with broader interoperability in mind? 

—  Which are in your view, the main technical aspects or parameters of 

interoperability? (e.g. frequency, power levels, communication 
protocol…) 

—  Which are the main technical barriers you see for increased 

interoperability within wireless charging? 

—  Can there be interferences with other devices operating on a similar 

frequency band? 

e.  What about backward compatibility? Is it a relevant aspect for product 

design?  

4.  The Voice of the Customer 

a. What factors and circumstances might mean increased utility and demand 

from consumers? 

b. What derived demand growth can be expected? (e.g., IoT, recommendation 

to install chargers in furniture) 

c.  What factors might hinder consumer adoption (e.g., Cyber Security, Health 

considerations)? 

d. Can consumer preferences be detected for features of the different 

standards? 

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5.  Standardization, Universality, and Efficiency 

a.  Is  there  a  significant  difference  between  technologies  in  terms  of  energy 

efficiency? 

b.  How efficiently does the standard you support transfer energy from the source 
to the device being charged? Is it capable of energy harvesting? What about 
standby losses? 

c.  Are  there  technologies  that  can  be  universally  operated  with  all  devices 
(regardless of interoperable device type)? In terms of technical and economic 
feasibility. 

d.  In recent years, other devices than smartphones have seen an increase in the 
use of  wireless charging,  such as  wearables  (e.g. smartwatches,  earbuds). 
Which  movements  do  you  envision  in  the  market?  Which  other  electronic 
devices you see might become relevant in the future, if any? 

e.  Would this implementation be attainable universally for all small electronics, 

or certain types would require certain standards? Why? 

f.  What regulations apply to different standards of wireless charging, especially 
the standard your organisation supports? (E.g. health and safety regulations) 

g.  Regarding the current state of technological development, do you think it is 
the right time to think about standardization, or should technical developers 
still be given room for trying out new solutions? 

h.  Do you think that the introduction of new regulation would be limiting or could 
potentially stop market fragmentation enhancing a more direct route towards 
universal wireless charging standard? 

151 

Getting in touch with the EU 

In person 

All over the European Union there are hundreds of Europe Direct centres. 
You can find the address of the centre nearest you online (european-
union.europa.eu/contact-eu/meet-us_en). 

On the phone or in writing 

Europe Direct is a service that answers your questions about the European 
Union. You can contact this service: 

–  by freephone: 00 800 6 7 8 9 10 11 (certain operators may charge for 

these calls), 

–  at the following standard number: +32 22999696, 
–  via the following form: european-union.europa.eu/contact-eu/write-us_en. 

Finding information about the EU 

Online 

Information about the European Union in all the official languages of the EU is 
available on the Europa website (european-union.europa.eu). 

EU publications 

You can view or order EU publications at op.europa.eu/en/publications. 
Multiple copies of free publications can be obtained by contacting Europe 
Direct or your local documentation centre (european-union.europa.eu/contact-
eu/meet-us_en). 

EU law and related documents 

For access to legal information from the EU, including all EU law since 1951 
in all the official language versions, go to EUR-Lex (eur-lex.europa.eu). 

EU open data 

The portal data.europa.eu provides access to open datasets from the EU 
institutions, bodies and agencies. These can be downloaded and reused for 
free, for both commercial and non-commercial purposes. The portal also 
provides access to a wealth of datasets from European countries. 

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