7A-i 

APPENDIX 7A. BATTERY CHARGER AND EXTERNAL POWER SUPPLY USAGE 

PROFILES 

LIST OF TABLES 

TABLE 7A.1 APPLICATION STATES, LOADING POINTS, AND WEEKLY USAGE VALUES 

USED TO CALCULATE ENERGY CONSUMPTION FOR CLASS A EXTERNAL POWER 

SUPPLIES .............................................................................................................................................. 7A-1

TABLE 7A.2 DAILY USAGE VALUES USED TO CALCULATE ENERGY CONSUMPTION FOR 

BATTERY CHARGERS ........................................................................................................................ 7A-6

EERE-2008-BT-STD-0005 COMMENT 31
7A-1

This appendix lists the assumptions used to calculate reference-case unit energy consumption values for Class A external power 

supplies (Table 7A.1) and battery chargers (Table 7A.2). Applications states, usage profiles, and loading points used to calculate UECs for 

the low-savings and high-savings sensitivity analyses can be found in Appendix 8B. Applications are ordered by product category, per the 

diagram found in Appendix 3A. Sources for all of the usage profiles below can be found in the Excel workbook that accompanies chapter 7. 

For a discussion on how these values were derived and used, see chapter 7 of the technical support document for battery chargers and external 

power supplies. 

Table 7A.1 Application States, Loading Points, and Weekly Usage Values Used to Calculate Energy Consumption for Class A External 

Power Supplies 

Application

Application

State 1

Application

State 2

Applications

State 3

Application

State 4

Application

State 5

Application

State 6 No Load

[hrs/wk]

Unplugged

Loading [hrs/wk]

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Pre-Amps

Active Idle Sleep/Off

60.0% 6.72 2.0% 40.32 1.0% 120.96

Wireless Speakers

Active Idle Sleep/Off

60.0% 6.72 2.0% 40.32 1.0% 120.96

Guitar Effects 

Pedals

Active Idle

160

60.0% 5 2.0% 3

Keyboards

Active Idle Sleep/Off

60.0% 5 2.0% 3 1.0% 160

MP3 Speaker 

Docks

Active Idle Sleep/Off

60.0% 6.72 2.0% 40.32 1.0% 120.96

Clock Radios

Active

60.0% 168

MP3 Players

Charging Maintenance

59.5 56

37.1% 10.08 17.2% 42.42

Personal Digital 

Assistants

Charging Maintenance

49 77

37.1% 9.31 17.2% 32.69

Netbooks*

On and Charging Off and Charging On Sleep Off

42.35

66.3% 5.75 38.2% 5.75 28.1% 18.18 1.3% 5.98 0.6% 89.99

Notebooks* On and Charging On with DVD 

playing Off and Charging On Sleep Off 26.60

EERE-2008-BT-STD-0005 COMMENT 31
7A-2

Application

Application

State 1

Application

State 2

Applications

State 3

Application

State 4

Application

State 5

Application

State 6 No Load

[hrs/wk]

Unplugged

Loading [hrs/wk]

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

66.3% 4.14 57.1% 5.18 38.2% 4.14 28.1% 25.03 1.3% 21.76 0.6% 81.14

Computer Speakers

Active Off

60.0% 63.33 1.0% 104.67

External Hard 

Drives

Active Idle

63 63

60.0% 21 2.0% 21

External Media 

Drives

Active Idle

63 63

60.0% 21 2.0% 21

Image Scanners

Active Idle Sleep/Off

60.0% 5 2.0% 3 1.0% 160

Handheld Image 

Scanners

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Ink Jet Imaging 

Equipment

Active Ready Off

60.0% 5.06 15.2% 11.38 10.3% 151.57

Portable Printers

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

E-Books

Charging Maintenance

59.5 56

37.1% 10.08 17.2% 42.42

LAN Equipment*

On

45.5% 168

Wi-Fi Access 

Points*

On

45.5% 168

In-Vehicle GPS

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Handheld GPS

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Bluetooth Headsets

Charging Maintenance

49 77

37.1% 9.31 17.2% 32.69

Consumer TwoWay Radios

Charging Maintenance

36.75 98

37.1% 7.6825 17.2% 25.5675

Mobile Phones* Charging Maintenance 49 77

EERE-2008-BT-STD-0005 COMMENT 31
7A-3

Application

Application

State 1

Application

State 2

Applications

State 3

Application

State 4

Application

State 5

Application

State 6 No Load

[hrs/wk]

Unplugged

Loading [hrs/wk]

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

42.7% 20.93 23.9% 21.07

Caller ID Devices

Active

60.0% 168

Cordless Phones*

Charging Maintenance No Battery

32.9% 144.68 27.4% 8.2032 14.1% 15.12

Answering 

Machines*

Charging Maintenance No Battery

32.9% 144.68 27.4% 8.2032 14.1% 15.12

VoIP Adapters

Transmitting Idle

60.0% 7 2.0% 161

Baby Monitors

Charging Maintenance

3.5

37.1% 7 17.2% 157.5

Breast Pumps

Active Idle

160

60.0% 5 2.0% 3

RC Toys

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Portable Video 

Game Systems*

Charging Maintenance

59.5 56

35.1% 3.9 2.4% 48.6

Video Game 

Consoles*

On with Disc No Disc - Idle Off

49.8% 31.07 42.6% 2.88 1.2% 134.05

Handheld Vacuums

Charging Maintenance

1

8 17.2% 159

Robotic Vacuums

Charging Maintenance

3.5

37.1% 7 17.2% 157.5

Stick Vacuums

Charging Maintenance No Battery

37.1% 8 17.2% 159 14.1% 1

Electronic Pest 

Repellents

Active

60.0% 168

Home Security 

Systems

Maintenance

17.0% 168

Irrigation Timers Active

EERE-2008-BT-STD-0005 COMMENT 31
7A-4

Application

Application

State 1

Application

State 2

Applications

State 3

Application

State 4

Application

State 5

Application

State 6 No Load

[hrs/wk]

Unplugged

Loading [hrs/wk]

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

60.0% 168

Water 

Softeners/Purifiers

Active Idle

60.0% 5 2.0% 163

Blenders

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Can Openers

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Electric Knives

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Mixers

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Camcorders

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Digital Cameras

Charging Maintenance

4.76 152.6

37.1% 3.38 17.2% 7.26

Digital Picture 

Frames

Active

60.0% 168

Portable DVD 

Players

Active Idle

160

60.0% 5 2.0% 3

Air Mattress Pumps

Active Idle

160

60.0% 5 2.0% 3

Aquarium 

Accessories

Active

60.0% 168

Indoor Fountains

Active

60.0% 168

Flashlights/Lanterns

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Universal Battery 

Chargers

Charging Maintenance

37.1% 0.7 17.2% 167.3

Weed Trimmers Charging Maintenance 161

EERE-2008-BT-STD-0005 COMMENT 31
7A-5

Application

Application

State 1

Application

State 2

Applications

State 3

Application

State 4

Application

State 5

Application

State 6 No Load

[hrs/wk]

Unplugged

Loading [hrs/wk]

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

Loading 

Point

Usage

[hrs/wk]

37.1% 2.8 17.2% 4.2

Hedge Trimmers

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Lawn Mowers

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Rechargeable 

Toothbrushes

Charging Maintenance

59.5 56

37.1% 10.08 17.2% 42.42

Rechargeable water 

Jets

Charging Maintenance

59.5 56

37.1% 10.08 17.2% 42.42

Beard and 

Mustache Trimmers

Charging Maintenance

3.5

37.1% 7 17.2% 157.5

Hair Clippers

Charging Maintenance

161

37.1% 2.8 17.2% 4.2

Shavers

Charging Maintenance

3.5

37.1% 7 17.2% 157.5

DIY Power Tools 

(Integral)

Charging Maintenance

3.99 121.86

37.1% 2.01 17.2% 40.14

DIY Power Tools 

(External)

Charging Maintenance No battery

1.99 121.86

37.1% 2.01 17.2% 40.14 14.1% 1.99

Electric Scooters

Charging Maintenance

59.5 56

37.1% 10.08 17.2% 42.42

Motorized Bicycles

Charging Maintenance

59.5 56

37.1% 10.08 17.2% 42.42

Toy Ride-On 

Vehicles

Charging Maintenance

59.5 56

37.1% 10.08 17.2% 42.42

*Loading points derived from DOE test data. 

EERE-2008-BT-STD-0005 COMMENT 31
7A-6

Table 7A.2 Daily Usage Values Used to Calculate Energy Consumption for Battery Chargers 

Application

Active + Maintenance No Battery Unplugged Off

Charges/ Day

[hrs/day] [hrs/day] [hrs/day] [hrs/day]

Wireless Speakers 1.00 23.00 0.14

MP3 Speaker Docks 1.00 23.00 0.14

MP3 Players 7.50 8.50 8.00 0.29

Personal Digital Assistants 3.50 8.50 12.00 0.29

Netbooks 18.00 0.00 6.00 0.71

Notebooks 20.23 0.17 3.60 0.51

Uninterruptible Power Supplies 24.00 0.00

Portable Printers 1.00 23.00 0.14

E-Books 1.00 23.00 0.14

In-Vehicle GPS 1.00 23.00 0.14

Handheld GPS 1.00 23.00 0.14

Bluetooth Headsets 13.00 11.00 0.43

Consumer Two-Way Radios 4.63 5.38 14.00 0.55

Mobile Phones 6.00 7.00 11.00 0.71

Cordless Phones 21.84 2.16 0.71

Answering Machines 21.84 2.16 0.71

Baby Monitors 23.50 0.50 0.14

RC Cars (Hobby Grade) 1.00 23.00 0.14

RC Toys 1.00 23.00 0.14

Portable Video Game Systems 7.50 8.50 8.00 0.29

Handheld Vacuums 23.90 0.10 0.20

Robotic Vacuums 23.50 0.50 0.50

Stick Vacuums 23.90 0.10 0.20

Home Security Systems 24.00 0.02

Blenders 1.00 23.00 0.14

Can Openers 1.00 23.00 0.14

Electric Knives 1.00 23.00 0.14

Mixers 1.00 23.00 0.14

Camcorders 0.27 0.27 23.46 0.04

Digital Cameras 1.03 1.17 21.80 0.09

Portable DVD Players 4.00 20.00 0.04

EERE-2008-BT-STD-0005 COMMENT 31
7A-7

Application

Active + Maintenance No Battery Unplugged Off

Charges/ Day

[hrs/day] [hrs/day] [hrs/day] [hrs/day]

Air Mattress Pumps 1.00 23.00 0.14

Flashlights/Lanterns 12.50 0.01 11.50 0.09

Universal Battery Chargers 16.00 4.00 4.00 0.07

Weed Trimmers 6.15 0.05 17.80 0.05

Hedge Trimmers 6.15 0.05 17.80 0.05

Lawn Mowers 22.00 2.00 0.05

Rechargeable Toothbrushes 23.90 0.10 0.26

Rechargeable water Jets 23.90 0.10 0.26

Beard and Mustache Trimmers 1.00 23.00 0.14

Hair Clippers 1.00 23.00 0.14

Shavers 14.15 2.03 7.82 0.19

DIY Power Tools (Integral) 12.30 0.10 11.60 0.10

DIY Power Tools (External) 6.78 1.10 15.32 0.80 0.64

Professional Power Tools 8.00 16.00 2.70

Electric Scooters 15.50 8.50 0.43

Motorized Bicycles 15.50 8.50 0.43

Golf Carts 7.74 8.13 8.13 0.36

Toy Ride-On Vehicles 3.91 0.10 20.00 0.70

Wheelchairs 12.00 12.00 0.70

Mobility Scooters 12.00 12.00 0.70

Marine/Automotive/RV Chargers 22.00 2.00 0.05

Sleep Apnea Machines 24.00 0.02

Medical Nebulizer 12.00 12.00 1.00

Portable O2 concentrator - Higher Output 1.00 23.00 0.14

Portable O2 concentrator - Others 1.00 23.00 0.14

Wireless Headphones 23.50 0.50 0.14

EERE-2008-BT-STD-0005 COMMENT 31