Electricity System 2021
The Spanish 
Electricity System

Glossary of terms
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Information prepared with data
available as at 8 April 2022
Published by
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EUROPUBLIC
Other details of the publication
Date of publication: June 2022
This English version is a translation of 
the original and authentic Spanish text 
found in the ‘El sistema eléctrico español 
2021’ report, originally issued in Spanish. 
In the event of discrepancy, the original 
Spanish language version shall prevail.

Electricity 
System Report
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Presentation
Electricity Demand
Electricity Generation
Electricity Markets
Scheduled International 
Electricity Exchanges
The European 
Landscape
Electricity 
Transmission
Regulatory 
Framework
Executive Summary
1
2
10
24
78
54
96
70
102
4
2
5
3
6
4
7
Table of contents

Electricity 
System Report
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PRESENTATION

3
The Spanish Electricity System 2021
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Red Eléctrica, as transmission agent and operator of the Spanish electricity system, 
presents the 2021 edition of the Spanish Electricity System Report, which the Company has 
been publishing annually ever since it was established as Transmission System Operator 
(TSO) in 1985. As in previous years, this publication provides an overview of the main 
operational performance indicators and statistical ratios regarding the Spanish electricity 
system, as well as the evolution of this data over recent years. All of the aforementioned 
in an energy environment which was impacted by the prolonged health crisis resulting 
from COVID-19 and by new conditioning factors at the end of the year which, directly 
or indirectly, were influenced by the evolution of the pandemic. This situation also had 
repercussions on the evolution of economic activity: disruptions in the supply chain of 
intermediate products and the rise in the price of raw materials and fuels.
The information contained in this report is intended to be used as a management and 
reference tool in the current energy transition context, in which the electricity system is 
paramount and where Red Eléctrica, as a key facilitator of this transition, is entrusted the 
mission of achieving the objectives set out in the European Green Deal and in Spain’s 
National Energy and Climate Plan (NECP).
The success of this energy transition will be underpinned by the connection of renewable 
energy generation to the transmission grid at the required pace. An example of this has been 
the high level of connection of renewable energy capacity over recent years. In 2021, our 
power generation fleet incorporated almost 4,500 MW of installed renewable power capacity.
Once again, this year’s report includes the ‘European Landscape’ chapter with information 
coming from the ENTSO-E Transparency Platform that includes data that complies with the 
criteria of Regulation (EU) No 543/2013.
The report is supplemented by Excel files that expand on the information and allow the data 
to be viewed online or downloaded. The digital version of the report along with the new 
‘Renewable Energy in the Spanish Electricity System’ report that provides a greater depth 
of information on renewable energy generation and consumption can be found and viewed 
directly in the REData section of the corporate website: www.ree.es/en, allowing the user to 
access the data in a more interactive and flexible way. These reports can be found along 
with other publications and statistical data that Red Eléctrica periodically makes available 
to the general public for their consultation and use. 
As part of its continued effort to improve, Red Eléctrica’s aim is to offer a quality service for 
all users and for this reason a contact form is also made available in the REData section, as 
a channel through which suggestions and observations may be submitted.

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EXECUTIVE 
SUMMARY

5
The Spanish Electricity System 2021
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In 2021, the demand for electricity in Spain grew 
after two consecutive years of decline.
Executive Summary 2021
The demand for electrical energy 
in Spain during 2021 showed an 
increase of 2.6% compared to 
the previous year, reaching a total 
demand of 256,482 GWh, impacted 
by the prolonged COVID-19 crisis 
which meant that the values prior 
to the pandemic have not yet 
recovered.
Electricity demand  
in Spain 
256,482 GWh
+2.6 %
compared to 
2020

6
Electricity 
System Report
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The demand for electricity in Spain in 2021 showed an increase of 2.6% compared 
to the previous year, reaching a total demand of 256,482 GWh. This is the first year of 
growth after two consecutive years of declining demand.
The evolution of the peninsular electricity system demand, which represents just over 
94% of total demand nationwide, was 2.4% higher than the previous year, with a total of 
242,492 GWh. This demand is at similar levels to those recorded 16 years ago in 2005, 
although similar values were also recorded in 2014 during the period of the strongest 
depression due to the crisis that began in 2009. After having factored in the effects of 
seasonal and working patterns, there is a positive variation of 2.4% compared to the 
previous year, which contrasts with the 5% decline recorded in 2020.
By large sectors of activity, according to the Red Eléctrica Index (IRE) that collects 
data on the electricity demand of large consumers, figures show that they have grown 
with respect to the previous year:  the industry sector increased by 5.1%, the services 
sector registered a slightly bigger growth with an increase of 5.2%, and the grouping of 
other sectors of activity also increased by 0.9%.
The composition of the working calendar and the evolution of temperatures had a 
negative impact on the trend registered by the IRE, with the magnitude of temperature 
having twice the impact as that of the working calendar, subtracting 0.6 percentage 
points and 1.2 percentage points, respectively.
By geographical areas, the continuation of the effects of the pandemic during 2021 
led to a positive variation in demand in most of the Spanish autonomous communities, 
although lower than the average growth nationwide, with the exception of Ceuta and 
Melilla, which showed a negative variation.
Installed power capacity in Spain
113,156 MW
Renewable energy facilities
56.7 %

The Spanish Electricity System 2021
7
Executive Summary 2021
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The maximum demand was recorded on 8 January between 1:00 p.m. and 2:00 p.m. 
with a total of 41,483 MWh, an increase of 3.7% compared to the maximum value 
registered the previous year. 
The installed power capacity of the power generation fleet in Spain increased by 
2.1%, closing 2021 with 113,156 MW. Renewable installed power capacity in the national 
electricity system increased by 4.3 GW, which increased the installed power capacity of 
renewable generation sources to 56.7% of the total installed power capacity.
In terms of electricity generation, there was a new all-time high in peninsular 
renewable generation with a 48.4% share of the total electricity generation mix as a 
result of an increase in wind power and solar photovoltaic production, which were 10% 
and 37.4% higher than the previous year, respectively.
The share of non-renewable generation stood at 51.6% of the peninsular total, a 
decrease of 2.9 percentage points compared to the previous year when non-renewable 
generation represented 54.5%. This decrease in non-renewable generation on the 
Spanish mainland is mainly due to the lower production of nuclear and combined cycle 
power stations, which generated 3.1% and 2% less than in 2020, respectively. 
Maximum renewable generation 
on the Spanish peninsula
48.4 %
of the generation mix

8
Electricity 
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In 2021, the all-time minimum value of  
CO2 equivalent emissions associated with national 
electricity generation was registered, 35.9 million 
tonnes of CO2, 0.6% less than in 2020 and 67.7% 
below the level of emissions recorded in 2007.
The volume of scheduled energy exchanges between Spain and other countries 
registered a 55.7% fall with respect to the previous year. Exports grew by 22.8% to 
16,581 GWh, and imports grew to 18,043 GWh a value 7.4% higher than in 2020. Therefore, 
for the sixth consecutive year, a net import balance was recorded regarding the scheduled 
energy exchanges, registering a value of 1,462 GWh, 55.7% lower than in 2020. 
By interconnection, Spain was, for yet another year, a net importer with France and for 
the third consecutive year as a net exporter with Portugal. The cross-border connection 
with France recorded an import balance of 6,054 GWh (15.4% higher with respect to 
2020) and the cross-border connection with Portugal recorded an export balance of 
4,548 GWh, compared to 1,455 GWh in 2020. With Andorra, the balance was once again 
as an exporter, with 225 GWh, and with Morocco, it went back to being an importer, with 
a value of 182 GWh, compared to the 298 GWh exported last year. 
The electricity transmission grid continued to be bolstered in 2021 with the 
commissioning of 206 kilometres of new line circuit and 134 new substation bays, 
bringing the total length of line circuit in the national grid to 44,769 kilometres and 
there were 6,224 substation bays by the end of the year. In turn, transformer capacity 
increased by 850 MVA, bringing the total installed transformer capacity nationwide to 
93,871 MVA.
In 2021, noteworthy was the commissioning of 16 new substation bays for the expansion 
of renewable power, including the Almaraz, Brovales and Carmonita substations with a 
power capacity ranging between 0.7 and 1 GW. For the connection of railway axes,  
eight new substation bays were commissioned.

The Spanish Electricity System 2021
9
Executive Summary 2021
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The service quality indicators for 2021 remain below the maximum thresholds 
established in Royal Decree 1955/2000.
The Energy Not Supplied (ENS) in 2021 corresponding to the mainland system 
was 188 MWh (95 MWh in 2020) and the Average Interruption Time (AIT) stood at 
0.41 minutes (0.21 minutes in 2020). 
In the electricity system of the Balearic Islands, these indicators showed a clear fall 
over the previous year, with ENS closing the year at 1 MWh (4 MWh in 2020) and 
an AIT of 0.07 minutes (0.47 minutes in 2020). Something similar happened in the 
Canary Islands’ electricity system, with an ENS standing at 33 MWh (corresponding to 
4 electricity supply interruptions) and an AIT of 2.33 minutes.
Regarding the grid availability index (which measures the capacity or possibility of 
use of the different elements of the transmission grid by the system) corresponding to 
the peninsular system was 98.5%, slightly below the 98.57% recorded in 2020, and in 
the Balearic Islands and Canary Islands electricity systems, these indicators stood at 
98.61% (98.66% in 2020) and 99.2% (99.07% in 2020), respectively. 
The average final price of energy in the electricity market stood at 118.65 €/MWh, 
almost three times higher than last year and the highest value ever.
The combined price of the day-ahead and intraday market increased, reaching 
95.3%, which is the highest percentage ever, surpassing the 94.8% registered in 2008. 
The impact of ancillary services on the combined price represents 3.6%, very similar to 
the value in 2018 and capacity payments represent just 1.1%, a value much lower than in 
previous years.
Comparing the impact of the price on the demand served by the system with that of last 
year, it can be seen that the overall price corresponding to the day-ahead and intraday 
market has almost tripled, that of ancillary services increased by 68.5% and capacity 
payments saw a reduction of almost 51%.
At European level and in a context still impacted by the pandemic, in 2021 electricity 
demand in all the European countries belonging to ENTSO-E increased by 3.9% and the 
electricity generation from renewable sources continued to be promoted.

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1

11
The Spanish Electricity System 2021
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The demand for electricity in Spain during 
2021 showed an increase of 2.6% compared to 
the previous year, reaching a total demand of 
256,482 GWh.
Electricity Demand
The demand in the peninsular 
electricity system represented 
slightly more than 94% of total 
Spanish demand, which was 2.4% 
higher than the previous year, with a 
total of 242,492 GWh.
Electricity demanded 
in Spain was 
256,482 GWh
+2.6 %
compared 
to 2020

12
Electricity 
System Report
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The demand for electricity in Spain during 2021 showed an increase of 2.6% compared to 
the previous year, reaching a total demand of 256,482 GWh impacted by the prolonged 
effects of the COVID-19 crisis in 2021, which meant that the pre-pandemic values have 
not yet been recovered. In this regard, it would be necessary to add two new conditioning 
factors that, directly or indirectly influenced by the evolution of the pandemic, could have 
also affected the evolution of the activity, such as the disruptions in the supply chain of 
intermediate products and the rise in the price of raw materials.
The evolution of the peninsular electricity system, which represents slightly more than 94% 
of total Spanish demand, was 2.4% higher than the previous year, with a total demand of 
242,492 GWh. This demand is at similar levels to those recorded 16 years ago in 2005, 
although similar values were also recorded in 2014 during the period of the strongest 
depression due to the crisis that began in 2009.
Compared to the evolution of economic activity, both the electricity demand and GDP 
showed a positive variation, although the variation of GDP was stronger than that of electricity 
demand. In 2020, the opposite was the case, with GDP falling more sharply than demand. 
This joint variation gave rise to an elasticity between both magnitudes of 0.5. That is, activity 
measured through GDP was growing twice as much as electricity demand, this being the 
second consecutive year in which this situation occurred, showing that, both in the fall of 
2020 and in the subsequent rebound, both magnitudes maintained an even behaviour.
Evolution of the peninsular electricity demand 
over the last 10 years
TWh
255
250
245
240
235
230
225
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
252
246
243
248
250
253
254
249
237
242

13
1  Electricity Demand
The Spanish Electricity System 2021
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In any case, the evolution of the elasticity relationship between electricity demand and GDP 
maintains a low rate, as it has shown in recent years: elasticity of 0.1 in the period 2017-2021. 
In other words, in recent years the relationship between these variables has been 
practically negligible, as has become evident following the economic recovery that occurred 
after the 2009 crisis.
After having factored in the influence of seasonal and working patterns, although practically nil 
regarding temperature, the result is a positive variation of 2.4% with respect to the previous 
year, which contrasts with the 5% decrease recorded the previous year, showing a certain 
recovery in 2021, although without reaching the levels seen prior to the start of the pandemic.
Demand at  
substation busbars
 
Working Patterns 
 
Temperature
 
Adjusted value
2012 
-1.3    
-0.3     
0.7     
-1.7    
2013 
-2.3     
0.4    
-0.3    
-2.4    
2014 
-1.1    
0.0    
-1.0    
-0.1    
2015 
2.0    
-0.1    
0.4    
1.7    
2016 
0.7     
0.3     
0.1     
0.3     
2017 
1.1     
-0.1     
-0.2     
1.4     
2018 
0.4     
-0.3     
0.2     
0.5     
2019 
-1.7    
0.7     
0.2     
-2.7    
2020 
-5.0     
-0.1     
0.1     
-5.0    
2021 
2.4    
0.1     
0.0     
2.4     
Annual variation of the peninsular electricity 
demand and Spanish GDP
% year-on-year 
Components of the annual variation in peninsular 
electricity demand
%
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
10
5
0
-5
-10
-15
  GDP           
  Adjusted peninsular demand

14
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As for the trend, this was conditioned by the impact that the successive waves of the 
COVID-19 pandemic had on society and the economy. Thus, between the months of 
March and June, there were strong rebounds in demand, compared to the same months 
of 2020, due to the fact that this was when the most restrictive measures were taken to 
try to contain the pandemic. In the following months, the different waves of the pandemic 
prevented activity from returning to normality, so that positive monthly variations alternate 
with negative ones, in comparison with the previous year, ending the year with the impact 
due to the sixth wave of the omicron variant that has even continued into the first few 
months of 2022. It should be noted that the campaign carried out that vaccinated a high 
percentage of the Spanish population favoured a certain recovery in activity, although 
other factors such as the increase in the price of raw materials or the disruptions in the 
supply chain of certain components had a negative impact on the recovery began after the 
initial effects of the pandemic.
Monthly variation in the adjusted electricity demand 
on the Spanish peninsula in 2021
%
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
20
15
10
5
0
-5
-10
  Month           
  Rolling Year
Compared to the evolution of economic activity, both the 
electricity demand and GDP showed a positive variation, 
although the variation of GDP was stronger than that of 
electricity demand, which has given way to an elasticity 
between both magnitudes of 0.5.

15
1  Electricity Demand
The Spanish Electricity System 2021
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From the point of view of the influence of temperatures on demand, the whole of 2021 
compared to the historical average, showed warmer temperatures in summer and milder 
temperatures in winter. The daytime temperatures with a cooling effect (Cooling Degree 
Days) were 6.2% lower than the average values and the daytime temperatures with a 
heating effect (Heating Degree Days) were 14.8% higher than the average values for the 
period considered. In other words, over the year as a whole, the number of days with 
warmer than average temperatures was higher.
Thus, in 2021, temperatures were much higher than the historical average temperature on 
21% of the days, which were more concentrated in August for the summer months, and in 
December for the winter months. On the other hand, on days with temperatures below the 
historical average, this situation only occurred on 11.7% of the days in the year and these 
days were mainly in January and November. 
Evolution of the daily maximum temperatures 
compared to the historical average
ºC
Monthly evolution of maximum temperatures
ºC
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
40
35
30
25
20
15
10
5
0
35
30
25
20
15
10
5
0
  Historical average           
  2020           
  2021
  Above average           
  Below average
INCREASED NUMBER OF DAYS WITH WARMER TEMPERATURES

16
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Compared to the previous year, 2021 was colder in winter and not as hot in summer 
compared to 2020, registering 19.2% more ‘cold days’ and 13.3% fewer ‘hot days’.  
The combined impact of these temperatures resulted in a slightly negative impact of 
-0.04 percentage points on demand growth.
Elements associated with the variation in monthly 
demand on the Spanish peninsula 2021
%
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
20
15
10
5
0
-5
-10
  Working patterns           
  Temperature           
  Economic activity           
  Increase in demand
2021 was colder in 
winter and not as hot 
in summer compared 
to 2020, resulting in 
temperatures having a 
slightly negative impact of 
-0.04 percentage points 
on demand growth.
Influence of 
temperature on the 
demand
21 %
of the days registered temperatures that 
were much higher than average

17
1  Electricity Demand
The Spanish Electricity System 2021
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The evolution of the IRE during 2021 recovered its growth trend but it too was not immune 
to the effects of the pandemic situation that was experienced as of March 2020 in which 
periods of restrictions on mobility and the limitation placed on certain activities had an 
impact on the IRE, especially with the arrival of the fourth, fifth and sixth waves.
In 2021, the overall IRE was 4.7% higher than in the previous year, an increase that does 
not offset the decline experienced in 2020, which was -7.4%. The index closed the year at 
120.6, compared with a value of 124.4 in 2019.
All the main sectors of activity that make up the IRE (industry, services sector and the 
grouping of other activities), experienced a positive variation compared to the previous 
year, although with different intensities depending on the particular sector of activity:
	
—
Industrial activities grew 5.1%, showing accelerated growth in consumption after the 
substantial fall registered the previous year.
	
—
The services sector had a slightly greater impact, with an increase of 5.2%.
	
—
The grouping of ‘Other’ sectors of activity also increased with a variation of 0.9% over the 
previous year, although to a lesser extent than the main sectors.
Breakdown of the General IRE
%
INCREASED CONSUMPTION IN THE INDUSTRIAL  
AND SERVICES SECTORS
Services 
27 %
Other 
10 %
Energy, Water 
and Waste 
6 %
Industry 
63 %
Extractive 
1 %
Primary sector 
1 %
Construction 
2 %

18
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System Report
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In 2020, both the composition of the working calendar and the evolution of temperatures had a 
negative impact on the evolution of the Red Eléctrica Index, with the magnitude of temperature 
having twice the impact than that of the working calendar.
Temperatures had a negative impact of 1.2 percentage points on the evolution of the IRE, 
noteworthy were May and July, when temperature had a negative impact of 4.9 and 4.8, 
respectively. By main sectors, the most significant impact was in industry, where temperature 
had an influence of -1.7 percentage points on the IRE, followed by the services sector, where 
temperatures had a negative effect of just over 0.1, and that of the ‘Other’ sectors that had an 
impact of slightly less than 0.1%.
Annual variation of the IRE
% year-on-year
2017
2018
2019
2020
2021
6
4
2
0
-2
-4
-6
-8
-10
-12
  General           
  Industry           
  Services           
  Other
Gross  
Working patterns 
Temperature
Adjusted value
General
4.7 
-0.6
-1.2
6.6
Industry
5.1 
-0.5
-1.7
7.4
Services
5.2 
-1.0
-0.1
6.3
Other
0.9 
-0.8
-0.1
1.8
IRE: Breakdown of the variation in 2021
%
Temperatures had a negative impact of 1.2 percentage 
points on the evolution of the IRE, by main sectors, 
the most significant impact was in industry where 
temperature had an influence of -1.7 percentage points.

19
1  Electricity Demand
The Spanish Electricity System 2021
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Monthly evolution of the adjusted IRE  
% year-on-year
40
30
20
10
0
-10
-20
-30
  General           
  Industry           
  Services
The monthly evolution of the adjusted index was impacted by the recovery after the pandemic 
and its subsequent evolution. It is noteworthy, in any case, that the adjusted IRE had been 
achieving positive rates since the first months of the year, reaching double-digit variations that 
had not been seen since the IRE indicator began, as a consequence of the large falls registered 
in 2020. Thus, in the month of March, still immersed in the second state of emergency at a 
national level and with negative rates until February, the adjusted IRE increased by 4.1% with 
respect to the previous year, but it was in the month of April when it reached a maximum increase 
of 27.9%, taking into account that in April 2020 there was a ‘hibernation of the economy’, linked 
to a general lockdown and the suspension of non-essential activities. In the month of May, the 
index reflected an increase of 18.5% with respect to May of the previous year, when there was still 
a state of emergency and restrictions on mobility. From that month onwards, the index began to 
register positive rates, although moderate, that continued right up until the end of the year.
With respect to the monthly evolution of the adjusted index corresponding to the two main 
sectors (industry and services), it should be noted that although all sectors began to recover at 
the beginning of the year, the progressive recovery of the index did not take place with equal 
intensity, as while the industry sector registered a positive trend from the outset, the services 
sector was slower to recover and subsequently rallied later on in the year, helping the IRE to 
register positive rates in the last months of 2021.
The monthly evolution of the adjusted index registered positive 
rates as of the beginning of the year, reaching double-digit 
variations that had not been seen since the IRE indicator began.
JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV
2016
2017
2018
2019
2020
2021

20
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Monthly evolution of the change in trend of the 
adjusted IRE 
% year-on-year
10
5
0
-5
-10
-15
  General           
  Industry           
  Services
Regarding the trend, it should be noted that in 2020 the IRE was showing a downward 
trend with negative records being set throughout the year, conditioned by the evolution 
of all sectors, especially the services sector. This situation continued during the first two 
months of 2021 until, from March onwards, the trend of the index reached a turning point 
when it started to show positive values in the first months of summer. From that moment 
on, with the more positive evolution of industry, the trend took an upward turn, although 
maintaining negative variation rates in its comparison with 2019.
Since 2020, the services sector had been showing a more negative trend compared to the 
industry sector. The expectations and the relaxation of measures as of the second quarter 
of the year meant that since March the index of this sector show a clear upward trend that 
continued throughout the year without showing signs of weakening, which was motivated 
because this sector includes activities that were more influenced by the relaxation of the 
pandemic containment measures.
JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV JAN MARMAY JUL SEP NOV
2016
2017
2018
2019
2020
2021
Annual adjusted index  
for the services sector
+6.3 %
Annual adjusted index  
for the industry sector
+7.4 %

21
1  Electricity Demand
The Spanish Electricity System 2021
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Electricity demand by autonomous communities 
and variation year-on-year
GWh and % 
ALL AUTONOMOUS COMMUNITIES, EXCEPT CEUTA AND 
MELILLA, SHOWED AN OVERALL INCREASE IN DEMAND
The ongoing effects of the pandemic during 2021 led to an increase in demand in the 
majority of the autonomous communities, although lower than the average growth in Spain 
as a whole, with the exception of Ceuta and Melilla, which showed a negative variation.
On the mainland, the exceptions that caused the growth in demand to be somewhat higher 
were registered in the Basque Country 6.5%; Asturias 6.1%; Navarra 4.3% and the Community 
of Valencia 4%, autonomous communities that in 2020 had higher than average falls. In the 
non-peninsular systems, noteworthy was growth in the Balearic Islands which reached 11.9%, 
although it must be taken into account that the initial impact of the pandemic during 2020 in 
these islands was much higher, with a decrease of 19.2% in that year.
   < 0 %          
   de 0.0 % to 1.5 %          
   de 1.5 % to  4.0 %          
   > 4.0 %
ARAGÓN
10,471 GWh
3.5 %
NAVARRA
5,050 GWh
4.3 %
CATALONIA
44,666 GWh
1.4 %
BALEARIC 
ISLANDS
5,528 GWh
11.9 %
GALICIA
17,510 GWh
0.6 %
ASTURIAS
9,253 GWh
6.1 %
CANTABRIA
4,004 GWh
2.5 %
BASQUE 
COUNTRY
15,901 GWh
6.5 %
COMMUNITY 
OF VALENCIA
26,887 GWh
4.0 %
EXTREMADURA
5,060 GWh
2.2 %
MURCIA
9,333 GWh
1.4 %
CEUTA
197 GWh 
-1.2 %
MELILLA
205 GWh
-1.3 %
CANARY ISLANDS
8,061 GWh
1.4 %
CASTILLA Y LEÓN
13,670 GWh
1.8 %
CASTILLA-LA MANCHA
12,004 GWh
2.1 %
LA RIOJA
1,633 GWh
0.8 %
MADRID
27,413 GWh
1.9 %
ANDALUSIA
39,634 GWh
1.6 %

22
Electricity 
System Report
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After 4 years, the maximum annual demand during 
the winter months grew compared to previous years, 
registering the highest value since 2012.
In 2021, the maximum hourly demand in the winter months (which was actually the highest 
value registered throughout the year), was 3.7% higher than that recorded the previous year, 
reaching a demand of 41,483 MWh on 8 January between 1:00 p.m. and 2:00 p.m. This 
maximum value coincides with the cold wave that swept the peninsula at the beginning of 
January, with the particularity that it broke a run of four consecutive years of a downward trend 
in winter maximums and this maximum was the highest hourly value registered since 2012 
when the maximum value for the winter period was set at 43,411 MWh.
The summer peak occurred on 22 July between 1:00 p.m. and 2:00 p.m. with 36,923 MWh, a 
decrease of 4% compared to the 2020 peak value.
.
Annual maximum for instantaneous power on the 
Spanish peninsula 
MW
44,000
43,000
42,000
41,000
40,000
39,000
38,000
37,000
36,000
35,000
34,000
  Winter           
  Summer
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
Annual maximum
41,483 MWh
8 January
between 1:00 p.m. and 2:00 p.m.
+3.7 %
compared to 
2020

23
1  Electricity Demand
The Spanish Electricity System 2021
Go to table of contents
Breakdown of the maximum hourly electricity demand
8 January 2021
MWh
45,000
40,000
35,000
30,000
25,000
20,000
15,000
10,000
5,000
0
  IRE-Industry              
  IRE-Services              
  IRE-Other              
  Low voltage P≤10kW           
  Other (Small businesses and services)              
  Total energy losses              
  Demand as measured at power station busbars
Hourly profiles applied to the general low-voltage tariff with contracted power of 10 kW or less
At the time of the day when the maximum hourly demand for 2021 was registered, the 
residential sector accounted for 36% of consumption, while the industry sector of the IRE 
accounted for 24% of consumption, the large services sector in the IRE stood at 10% and 
small businesses and services stood at 24%. Throughout the peak day, the greatest impact 
of the industry sector occurred in the early hours of the morning, between 3:00 a.m. and 
5:00 a.m. reaching a total share of 31.5% of the demand (as measured at the power station 
busbars), while for the large services sector, the hourly period with the greatest impact was 
between 6:00 a.m. and 8:00 p.m. with a share in the demand of around 10.3%.
At the time of the day when the maximum hourly demand 
for 2021 was registered, the residential sector accounted 
for 36% of consumption, while the industry sector of the 
IRE accounted for 24% of consumption, the large services 
sector in the IRE stood at 10% and small businesses and 
services stood at 24%.
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021

Electricity 
System Report
www.ree.es/en
2

25
The Spanish Electricity System 2021
Go to table of contents
In the overall electrical energy balance, broken down 
by the type of energy used, renewables increased 
their share in the peninsular electricity generation 
mix reaching a new all-time high with a total share 
of 48.4% compared to 45.5% in 2020, mainly due 
to significant increases in wind power and solar 
photovoltaic energy generation.
Electricity Generation
Non-renewable energy reduced its 
share to 51.6% (54.5% in 2020).
Total generation on the Spanish 
peninsular reached
246,805 GWh
+3 %
compared  
to 2020

26
Electricity 
System Report
www.ree.es/en
In 2021, renewable energy reached new all-time highs 
of electricity generation.
The energy landscape in Spain in 2021 continued to make progress in its recovery after the 
impact of the COVID-19 pandemic. In this context, electricity generation in the peninsular 
system, which represents around 95% of total generation nationwide, increased by 3% in 
2021, reaching 246,805 GWh. The most significant variations with respect to the previous 
year were recorded by solar photovoltaic generation, which increased by 37.4%, while 
nuclear and combined cycle decreased their production by 3.1% and 2%, respectively.
The generation of electricity in the non-peninsular systems (13,100 GWh) grew by 10.4% 
with respect to the previous year, with a notable increase of 22% for combined cycle. 
On the other hand, noteworthy is the fall in coal-fired generation which was 79.9% lower 
compared to the previous year.
With regard to the overall generation balance, broken down by the type of energy used, 
renewable energy increased its share in the peninsular electricity generation mix by 9.6%, 
reaching a new all-time high with a total share of 48.4% compared to 45.5% in 2020, 
mainly due to significant increases in wind power and solar photovoltaic energy generation. 
On the other hand, non-renewable energy reduced its share to 51.6% (54.5% in 2020).
Evolution of renewable and non-renewable 
generation on the Spanish peninsula
%
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
0
10
20
30
40
50
60
70
80
90
100
  Renewables: hydroelectric, wind, solar photovoltaic, solar thermal, renewable waste and other renewables 
  Non-renewable: pumped storage (net supply), nuclear, coal, fuel/natural gas, combined cycle, cogeneration and non-renewable waste
48.4
51.6
54.5
61.1
59.8
66.3
59.6
63.3
57.8
58.1
68,5
45.5
38.9
40.2
33.7
40.4
36.7
42.2
41.9
31,5

27
2  Electricity Generation
The Spanish Electricity System 2021
Go to table of contents
National electrical energy balance (1)
(1) Allocation of generation units based on primary fuel. The net production of non-renewable and non-Hydro Management Units 
(HMU) facilities have their own consumption discounted. In these types of production, negative generation indicates that the 
electricity consumed for the power station’s uses exceeds its gross production.
(2) Includes biogas, biomass, marine and geothermal. 
(3) Pure pumped storage (net supply) + estimate of mixed pumped storage (net supply). 
(4) The Balearic Islands electricity system includes generation with auxiliary generation units. 
(5) Includes operation in open-cycle mode. The Canary Islands electricity system uses diesel as its main fuel.
(6) Positive value: energy input into the system; negative value: energy output from the system. 
(7) Positive value: importer balance; negative value: exporter balance. Increment values are not calculated when exchange balances have 
different signs.	
	
	
	
	
Peninsular system
Non-peninsular system
National Total
GWh
%21/20
GWh
%21/20
GWh
%21/20
Hydro
29,592
-3.4
3
-12.6
29,595
-3.4
Hydro-wind
-
-
23
18.2
23
18.2
Wind
59,184
10.0
1,312
18.9
60,496
10.2
Solar photovoltaic
20,504
37.4
451
19.4
20,954
36.9
Solar thermal
4,706
3.7
-
-
4,706
3.7
Other renewables (2)
4,709
5.3
10
-1.9
4,719
5.3
Renewable waste
751
23.9
127
6.3
878
21.0
Renewable generation
119,445
9.6
1,926
17.9
121,371
9.7
Pumped storage (net supply) (3)
2,649
-3.7
-
-
2,649
-3.7
Nuclear
54,041
-3.1
-
-
54,041
-3.1
Coal
4,941
3.0
45
-79.9
4,986
-0.7
Fuel/Natural gas (4)
0
-
4,049
-3.4
4,049
-3.4
Combined cycle (5)
37,581
-2.0
6,912
22.0
44,493
1.1
Cogeneration
26,036
-3.6
41
22.2
26,078
-3.5
Non-renewable waste
2,110
11.3
127
6.3
2,238
11.0
Non-renewable generation
127,359
-2.5
11,175
9.2
138,534
-1.6
Pumped storage consumption
-4,318
-6.7
-
-
-4,318
-6.7
Peninsula-Balearic Islands link (6)
-890
-37.6
890
-37.6
0
-
International exchange balance (7)
895
-72.7
-
-
895
-72.7
Demand (measured at busbars)
242,492
2.4
13,991
5.2
256,482
2.6

28
Electricity 
System Report
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Breakdown of installed power capacity as at 31.12.2021.
National electricity system
(1) Includes biogas, biomass, marine-hydro and geothermal.
Peninsular system
Non-peninsular system
National Total
MW
%21/20
MW
%21/20
MW
%21/20
Hydro
17,093
0.0
2
0.0
17,094
0.0
Hydro-wind
-
-
11
0.0
11
0.0
Wind
27,772
2.8
563
19.6
28,336
3.0
Solar photovoltaic
14,840
30.0
334
22.7
15,174
29.9
Solar thermal
2,304
0.0
-
-
2,304
0.0
Other renewables (1)
1,087
0.1
6
0.0
1,093
0.1
Renewable waste
132
10.8
38
0.0
170
8.1
Renewable generation
63,227
7.1
954
19.2
64,182
7.2
Pumped storage (net supply)
3,331
0.0
-
-
3,331
0.0
Nuclear
7,117
0.0
-
-
7,117
0.0
Coal
3,523
-35.9
241
0.0
3,764
-34.3
Fuel/Natural gas
8
-
2,400
0.0
2,408
0.0
Combined cycle
24,562
0.0
1,688
0.0
26,250
0.0
Cogeneration
5,613
-0.9
50
0.0
5,663
-0.9
Non-renewable waste
402
3.3
38
0.0
441
3.0
Non-renewable generation
44,557
-4.3
4,418
0.0
48,975
-3.9
Total
107,784
2.1
5,372
2.9
113,156
2.1
Installed power capacity in  
the National Electricity System
113,156 MW
56.7 %
installed renewable 
power capacity 
nationwide

29
2  Electricity Generation
The Spanish Electricity System 2021
Go to table of contents
The peninsular electricity system moved towards a 
more sustainable energy model.
As at 31 December 2021, the power generation fleet of the peninsular system had increased 
by 2.1% with respect to the previous year and had reached an all-time record with an installed 
power capacity of 107,784 MW. 
In recent years, Red Eléctrica has successfully faced the challenge of integrating a large quota 
of new renewable power capacity, as a result of the 2017 renewable auctions carried out by 
the Ministry of Ecological Transition and the Demographic Challenge (MITERD). In 2019, the 
installed renewable power capacity in the peninsular electricity system increased by 6.4 GW 
and 4.7 GW in 2020. Similarly, in 2021, renewable installed power capacity increased by an 
additional 4.2 GW, bringing the total of installed renewable power capacity up to 63.2 GW in the 
peninsular electricity system. This represents a total installed power capacity of 58.7%.  
The integration of this new renewable capacity, mostly wind and solar photovoltaic, represents a 
strong boost to the energy transition and furthermore complies with the integration roadmap set 
out in Spain’s National Energy and Climate Plan (NECP), with a 2030 horizon.
The power generation fleet on the mainland is increasingly renewable due to the increase in 
2021 of installed wind power capacity, 2.8%, solar photovoltaic, 30% and renewable waste, 
10.8%, compared to 2020.
On the other hand, installed non-renewable power capacity in the peninsular system decreased 
by 4.3%, as a result of the 35.9% reduction in installed coal-fired power capacity due to the 
definitive closure of thermal unit 4 of the Lada power station, thermal units 1 and 2 of the Litoral 
de Almería power station and thermal units 2 and 3 of the Narcea power station, which combined 
represent a reduction of 1,969 MW of installed non-renewable power capacity on the mainland.
In the non-peninsular systems, there was an increase of 2.9% in installed power capacity by the 
end of 2021. This increase is mainly explained by the growth in installed wind power capacity of 
19.6% and solar photovoltaic of 22.7% with respect to 2020.
In Spain as a whole, which includes the peninsular and non-peninsular systems, installed 
power capacity increased by 2.1% compared to the previous year, closing 2021 at 113,156 MW. 
Renewable energy facilities account for 56.7% of the total installed power capacity nationwide.
Evolution of the structure of installed power capacity on 
the Spanish peninsula
MW
 Hydro      
 Pumped storage      
 Nuclear      
 Coal      
 Fuel/natural gas      
 Combined cycle      
 Wind      
 Solar photovoltaic 
 Solar thermal      
 Other renewables      
 Cogeneration      
 Non-renewable waste      
 Renewable waste (1)
(1) Power capacity included in other renewables and cogeneration until 31/12/2014. // Source: National Commission on Markets and Competition (CNMC) 
until 2014 regarding: non-Hydro Management Units (HMU), wind, solar photovoltaic, solar thermal, other renewables, cogeneration and waste to energy.
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
0
20,000
40,000
60,000
80,000
100,000
120,000

30
Electricity 
System Report
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Evolution of the Minimum Coverage Ratio (MinCR) 
for the Spanish peninsula
The minimum coverage index for the Spanish peninsula, 
defined as the minimum value of the ratio between 
the power available in the system and the peak power 
demanded from the system, stood at 1.09 in 2021.
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
0.4
0.6
0.8
1.0
1.2
1.4
1.6
MinCR = Min (Pa/Pd)
MinCR: Minimum Coverage Ratio
Pa: Power available in the system.
Pd: Peak power demanded from the system.
12 December
1.38
2 December
1.43
20 October
1.44
23 November
1.37
16 November
1.30
15 November
1.27
19 November
1.28
10 November
1.28
30 November
1.09
8 February
1.46
To enable the operation of an electricity system with such a high penetration of renewable 
energy under safe conditions, the control and supervision work carried out by Red Eléctrica’s 
Control Centre for Renewable Energies (CECRE) is essential. In 2021, CECRE celebrated its 
15th anniversary and, since its commissioning, it has continued to be a pioneering centre of 
worldwide reference for the integration of renewable energy.
The work of CECRE has made it possible that in 2021 the contribution of renewable energy 
to peninsular electricity generation set a new all-time high, reaching a share of 48.4% in the 
generation mix, 2.9 percentage points higher than the previous peak recorded in 2020 when 
renewables accounted for 45.5% of the mix. This higher share of renewable generation in 2021 
is mainly due to the increase in wind and solar photovoltaic production, 10% and 37.4% higher 
respectively than in the previous year, as a result of weather conditions and the increase in 
installed power capacity in the peninsular system.

31
2  Electricity Generation
The Spanish Electricity System 2021
Go to table of contents
This significant growth in the share of renewables in the peninsular generation mix was 
counterbalanced by a reduction in the share of the various technologies that use fossil fuels 
as a primary energy source. The share of non-renewable generation stood at 51.6% of the 
mainland total, a decrease of 2.9 percentage points compared to the previous year, when the 
non-renewable share was 54.5%. This decrease in non-renewable generation is mainly due to the 
lower production of both nuclear and combined cycle power stations, which generated 3.1% and 
2% less than in 2020, respectively.
Maximum renewable generation on the mainland due to the increase 
in the contribution of wind and solar photovoltaic generation.
Evolution of renewable and non-renewable 
electricity production on the Spanish peninsula 
GWh
The net production of non-renewable and non-Hydro Management Units (HMU) facilities have their own consumption discounted. In these 
types of production, negative generation indicates that the electricity consumed for the power station’s uses exceeds its gross production.
 (1) Pure pumped storage (net supply) + estimate of mixed pumped storage (net supply). 
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
0
40,000
80,000
120,000
160,000
200,000
0
40,000
80,000
120,000
160,000
200,000
 Hydro      
 Wind      
 Solar photovoltaic 
 Solar thermal      
 Other renewables      
 Renewable waste
 Pumped storage(1)      
 Nuclear      
 Coal      
 Fuel/natural gas      
 Combined cycle      
 Cogeneration      
 Non-renewable waste
Renewable
Non-renewable
This year saw the highest levels of clean electricity 
being registered since records began.
Peninsular renewable production in 2021 increased by 9.6% over the previous year, standing at 
119,445 GWh and reaching a new all-time high for annual peninsular renewable production and 
a share of 48.4% in the generation mix on the Spanish mainland.
During almost every month of 2021 (except September, October and December) renewable 
generation was higher than the previous year, coinciding with the increase in wind and solar 
photovoltaic production. The highest increases in renewable energy occurred during the first 
half of the year, with the highest growth recorded in February with a value of 42.7%, and in 
the same month, a new all-time high share of renewable energy in the peninsular generation 
mix was set at 60.5%. In addition, the highest values to date for renewable generation were 
recorded for the months of January, June, July and August.

32
Electricity 
System Report
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Regarding daily production, on the mainland on Saturday 30 January 2021 the all-time high was 
beaten for renewable generation reaching 544,980 MWh and, during that same day, 71.1% of the 
peninsular electricity production came from renewable sources.
Lastly, the hourly renewable production registered the all-time maximum level regarding its share 
in the generation mix on Saturday 30 January 2021 between 1:00 p.m. and 2:00 p.m. with a total 
of 76.6% of the peninsular production. The maximum hourly generation for the year was registered 
between 1:00 p.m. and 2:00 p.m. on Wednesday 8 December 2021 with a total of 27,826 MWh.
Wind power was the leading technology in the 
peninsular generation mix.
With regard to wind power, noteworthy was the 2.8% increase in installed power capacity 
registered during 2021, so wind power continued to be the generation technology with the most 
installed power capacity nationwide, with a total of 27,772 MW and represented more than a 
quarter of all the installed power capacity in the mainland electricity system.
In this way, in 2021 the peninsular power generation fleet added nearly 750 new MW of wind 
power capacity, which paved the way for several all-time records to be beaten during the year. 
Firstly, peninsular wind power production in 2021 set a new record with an annual total of 
59,184 GWh, which is 10% more than that recorded the previous year. This increase occurred 
mainly in the first and second quarters of the year, when wind generated 31.8% and 13.2% more 
than in the same periods of 2020, with January registering a 53.7% increase in production 
compared to the same month in 2020. In addition, January, February and July recorded the 
highest monthly wind power production to date for each of these months.
As a consequence of this growth, wind power was the leading technology in the peninsular 
generation mix with a share of 24%, the highest percentage registered since records began. 
This situation had only occurred previously in 2013 when wind shared the leading role in the 
peninsular generation mix with nuclear, with both technologies registering a share of 20.9%.
Wind was the technology with the highest share in the mainland generation mix during half of 
the months of 2021, specifically in January (30.1%), February (30.8%), March (26.1%),  
May (23.7%), November (28.9%) and December (30%).
Installed wind power capacity
27,772 MW
+2.8 %
Compared 
to 2020

33
2  Electricity Generation
The Spanish Electricity System 2021
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Annual generation mix of renewable energy in the 
peninsular system in 2021 
% 
With regard to daily wind power generation, during 2021 the all-time maximum record for 
peninsular wind power production was beaten on several occasions registering a new all-time 
record of 423,224 MWh on Wednesday 8 December, which represents an increase of 6.5% 
compared to the previous record high registered on Friday 13 December 2019.
Also on Wednesday 8 December 2021, a new maximum value for hourly generation was set 
between 1:00 p.m. and 2:00 p.m. with a value of 20,293 MWh and at 1:34 p.m. the record for 
instantaneous power for wind generation in the peninsular electricity system was beaten with 
a value of 20,130 MWh. This new maximum value represented an increase of 2.8% over the 
previous record of 19,588 MW, registered on Monday 28 December 2020 at 2:28 p.m.
During the month of December 2021, the all-time maximum value for instantaneous demand 
coverage using wind power generation on the peninsular was beaten twice. The first time took 
place on Wednesday 8 December at 5:07 a.m. when instantaneous wind power generation 
accounted for 81.9% of instantaneous demand in the mainland electricity system. This new 
maximum value represented an increase of 6 percentage points compared to the previous 
maximum value recorded on Sunday 3 November 2019 at 5:20 a.m. The second occasion 
on which the record was broken in 2021 was on Tuesday 28 December at 3:03 a.m. with a 
percentage of instantaneous demand coverage with peninsular wind power generation of 83.6%.
Wind power continues to be the most relevant renewable technology in the peninsular system, 
as in 2021 its production accounted for 49.5% of total renewable energy.
3.9 %
49.5 %
0.6 %
17.2 %
24.8 %
3.9 %
 Wind          
 Solar photovoltaic          
 Solar thermal          
 Other renewables          
 Renewable waste          
 Hydro

34
Electricity 
System Report
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Maximum, average and minimum daily coverage in 
2021 using hydro, wind and solar 
%
The enormous variability of wind power generation is evident as can be seen in the 
graph shown below of maximum and minimum daily coverage of renewable hydro, wind 
and solar technologies. During 2021, daily wind power production had a share in the 
generation mix that ranged from a minimum of 2.8% registered on 3 September to a 
maximum of 53.5% recorded on 8 December.
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
60
50
40
30
20
10
0
  Hydro           
  Wind           
  Solar
DAILY MAXIMUM AND MINIMUM
 values of wind power in the peninsular generation mix
MAXIMUM
  53.5 %
8 December
MINIMUM
  2.8 %
3 September

35
2  Electricity Generation
The Spanish Electricity System 2021
Go to table of contents
Peninsular hydroelectric generation 2020-2021 
compared to average generation
GWh
Hydroelectric generation on the mainland in 2021 reached 29,592 GWh, a decrease of 3.4% 
compared to 2020, which was a slightly wet year. Its contribution to the peninsular generation 
mix was 12% and this was 0.8 percentage points lower than the share this technology had in 
the energy mix the previous year. In 2021, the total electricity generated by hydroelectric power 
stations ranked this technology as the fourth source of generation in the peninsular total,  
as was the case in 2020.
The comparative graph, shown below, regarding peninsular hydroelectric generation 2020-2021 
shows how during all the months of 2021 hydroelectric production was only higher than that 
generated in 2020 in the period of January to March and during the month of July. The months in 
which hydroelectric production registered the greatest increases were February, with a growth of 
59.2%, and July, with generation 20.1% higher than in the same period of the previous year.  
On the contrary, the largest reduction in monthly hydroelectric production took place in November 
when hydroelectric power stations generated 51.5% less than in the same month of 2020.
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
5,000
4,000
3,000
2,000
1,000
0
  Hydroelectric generation in 2020           
  Hydroelectric generation in 2021           
  Historical average (1)
(1) Average monthly hydroelectric generation for the last 20 years.
In 2021, hydroelectric 
power stations on the 
mainland reduced their 
production compared to 
the previous year.
Peninsular  
hydroelectric generation
29.592 GWh
-3.4 %
Compared  
to 2020

36
Electricity 
System Report
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This decrease in hydroelectric generation was in line with the producible hydroelectric 
energy (maximum amount of electricity that theoretically could be produced considering 
the water reserves available), which in 2021 reached a value of 26,852 GWh, 12.2% 
less than that recorded in 2020 and 9.4% more than the annual historical average 
value. Therefore, we can consider that 2021 as a whole was a dry year as the producible 
hydroelectric index, defined as the quotient between producible energy and average 
producible energy, registered a value of 0.91.
Hydroelectric reserves during 2021 registered values 
below the statistical average.
In terms of the amount of precipitation, 2021 was a dry year overall. It started with a wet 
January, with precipitation 19% above average, and with an episode of heavy and persistent 
rains in which Storm Filomena gave rise to heavy precipitation in the form of snow in many 
areas of the interior of the peninsula on the 8th and 9th of the month. February was also 
wet, with an average rainfall 35% above the normal value for the month. The rest of the year 
had a very dry spring, a wet summer and a dry autumn. Finally, the months of October and 
November were dry while the month of December was normal in terms of rainfall.
In 2021, hydroelectric reserves were above the statistical average (calculated with the 
values of the last twenty years) only in the months of January, February and March. From 
April onwards, reserves began to fall every month until reaching the lowest point of the year 
between October and November with a fill level of 32.1%, a value that is around 13 percentage 
points lower than in the same months of the previous year.
Daily producible hydroelectric energy during 2021 
compared to the historical average producible
GWh
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
500
400
300
200
100
0
  Wet           
  Dry           
  Historical average producible           
  Producible 2021

37
2  Electricity Generation
The Spanish Electricity System 2021
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In the last month of the year, overall hydroelectric reserves rose slightly and registered a 
volume of water in hydroelectric reservoirs in Spain on 31 December 2021 that stood at 36% of 
their fill capacity, a value that is still 14.8 percentage points lower than that of the previous year.
In 2021, renewable energy once again improved its production values, especially in the 
case of solar photovoltaic. Thus, in 2021, the installed power capacity of this technology was 
the one that increased the most, incorporating almost 3,500 MW to the peninsular power 
generation fleet representing 13.8% of the mainland total.
This growth enabled its electricity production during 2021 to increase by 37.4%, reaching 20,504 
GWh, which represented a new record for annual generation. The annual share of this technology 
in the peninsular mix also registered a maximum value with a share of 8.3%, representing a 
growth of 2.1 percentage points compared to the share of solar photovoltaic a year earlier.
During all the months of 2021, solar photovoltaic production was higher than in the previous 
year, reaching 67% more in November than in the same month of 2020. Furthermore, during 
the month of July solar photovoltaic produced the highest monthly amount ever recorded with 
2,565 GWh and reached the highest share in the generation mix since records began with a 
value of 12.1%.
Regarding daily production, on Sunday 6 June 2021, solar photovoltaic production reached the 
highest share in the peninsular generation mix with 15.5% and on Tuesday 29 June 2021,  
the maximum value for solar photovoltaic production reached an all-time high of 90,594 MWh.
In terms of hourly generation, on Friday 14 May 2021, between 2:00 p.m. and 3:00 p.m. 
hourly solar photovoltaic energy broke the all-time record with a value of 9,351 MWh and 
on the same day, a new all-time high of instantaneous photovoltaic power generation in the 
peninsular electricity system was reached, with 9,337 MW recorded at 2:34 p.m.
Lastly, on Sunday 6 June 2021, between 1:00 p.m. and 2:00 p.m. peninsular solar photovoltaic 
production accounted for 32.8% of all peninsular generation and at 4:06 p.m. a new all-time 
high of instantaneous demand coverage using photovoltaic generation was reached in the 
peninsular electricity system with a value of 36.8%.
With regard to solar thermal generation on the Spanish peninsula, in 2021, a total of 
4,706 GWh was generated with this technology, 3.7% more than the previous year, and it 
contributed 1.9% to the total generation on the peninsula.
Production from ‘Other renewables’ (biogas, biomass, marine-hydro and geothermal) 
increased by 5.3% in 2021, reaching a new record high of 4,709 GWh of annual generation 
and contributing a share of 1.9% to the peninsular generation mix.
Solar photovoltaic 
generation reached 
all-time highs in 2021.
Peninsular solar 
photovoltaic generation
20,504 GWh
+37.4 %
Compared 
to 2020

38
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System Report
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Non-renewable energy in the peninsular system registered a total generation of 127,359 GWh 
in 2021, 2.5% lower than in 2020. This decrease in non-renewable generation resulted in a 
fall of 2.9 percentage points in its contribution to total peninsular generation, only reaching a 
share of 51.6% in 2021, compared to 54.5% in 2020.
Among non-renewable energy technologies, nuclear generated a total of 54,041 GWh in 2021, 
3.1% less than the previous year. This drop occurred mainly during the first and last quarter 
of 2021, when nuclear production fell 6.2% and 15.3%, respectively. In February nuclear 
generation decreased by 10.8% due to the operational unavailability of the Trillo power station, 
and in March the decrease was 6.6%, coinciding with the unavailability of the Almaraz II 
power station, which started the work corresponding to its twenty-sixth refuelling. The sharpest 
decreases in nuclear production occurred in November (23.2%) and December (25.6%) due to 
the refuelling stoppages at the Ascó 1, Cofrentes and Almaraz I power stations.
As a consequence of this lower level of production, nuclear power stations were for the 
first time the second source of peninsular generation after ten consecutive years of having 
occupied the leading spot in the peninsular generation mix (in 2013 they shared the leading 
position with wind). In 2021, nuclear reached an overall share in peninsular generation of 
21.9% (23.3% in 2020).
The utilisation rate (the ratio between actual production and the production that could have 
been achieved if the power stations had operated at their rated power for the entire time that 
they were available) was 97.5%.
Non-renewable generation fell due to lower production 
from nuclear and combined cycle power stations.
Peninsular electricity generation mix in 2020 and 2021
%
	
2020	
2021
Wind	
22.5 %	
24.0 %
Hydro	
12.8 %	
12.0 %
Solar photovoltaic 	
6.2 % 	
8.3 %
Solar thermal 	
1.9 % 	
1.9 %
Other renewables 	
1.9 % 	
1.9 %
Pumped storage (net supply)(1)	 1.1 %	
1.1 %
Nuclear	
23.3 %	
21.9 %
Coal	
2.0 %	
2.0 %
Combined cycle	
16.0 %	
15.2 %
Cogeneration 	
11.3 % 	
10.5 %
Non-renewable waste 	
0.8 % 	
0.9 %
Renewable waste	
0.3 % 	
0.3 %
(1) Pure pumped storage (net supply) + estimate of mixed pumped  
storage (net supply). 
2021
RENEWABLE 
48.4 %
NON_RENEWABLE 
51.6 %
2020
RENEWABLE 
45.5 %
NON-RENEWABLE 
54.5 %

39
2  Electricity Generation
The Spanish Electricity System 2021
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Regarding coal-fired power stations on the peninsular in 2021, after the drafting of the 
pertinent decommissioning reports their installed power capacity was reduced by 35.9% due 
to the definitive closure of the following thermal units:  in January, unit 4 (348 MW) of the Lada 
power station located in Langreo (Asturias), in February, units 2 (154 MW) and 3 (347 MW) of 
the Narcea power station located in Tineo (Asturias) and in December, units 1 (558 MW) and  
2 (562 MW) of the Litoral de Almería power station located in Carboneras (Almería). 
As a result, coal represented just 3.3% of the peninsular installed power capacity at the end 
of 2021, compared to the 5.2% share it had in 2020, and continues to be ranked in seventh 
position in the structure of the entire power generation fleet.
The peninsular coal-fired power stations in 2021 generated 4,941 GWh, which represented 
an increase of 3% compared to the previous year. In line with the energy transition, this 
technology maintains a reduced presence in the generation mix with a share of only 2% of 
all mainland generation.
During the first quarter of 2021, coal-fired production fell by 54.9% compared to the same period 
of the previous year, and in February, with 177 GWh, it recorded the sharpest decrease of the 
year, 78.5% lower than in February 2020, registering the lowest monthly production since records 
began. On the contrary, in the fourth quarter of the year, coal-fired power stations increased their 
production by 130.3% and in December it increased 224.8% due to the fact that December of the 
previous year was the second lowest record of coal-fired production registered to date.
Generation from coal-fired power stations registered 
its all-time low in February 2021.
The challenges of decarbonisation set by the European Union with the aim of reducing CO2 
emissions have meant that coal production, which is more polluting than other technologies, 
maintains a reduced share in the energy mix, representing 2% of total generation in 2021. 
In addition, in February, coal recorded the lowest monthly share since 1990 with 0.9% of the 
peninsular generation mix.
Monthly coal-fired generation  
all-time low
177 GWh
February 2021

40
Electricity 
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Utilisation rate of peninsular thermal power stations (1) 
MW
100
80
60
40
20
0
  Nuclear           
  Coal           
  Combined cycle
(1) The utilisation rate is the quotient between actual production and the available production or maximum production that the power 
station could achieve by operating at its rated power during the entire time it is are available.
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
In 2021, combined cycle power stations on the mainland 
reduced their output by 2%.
In line with the rest of the non-renewable technologies, combined cycle generation fell 
by 2% in 2021. Its annual production was 37,581 GWh, which is similar to the amount 
produced in 2012.
There was also a repetition of the situation of a ‘zero-day’ regarding coal in 2021, that is, an 
entire day without production using this fossil fuel, which occurred for the first time ever on  
14 December 2019. Specifically, in 2021 between 23 and 25 of January the peninsular electricity 
system was without coal-fired generation for a consecutive period of 50.5 hours, a situation that 
occurred again between 30 January and 1 February on this occasion for a consecutive period of 
54 hours when there was no production from coal-fired power stations on the mainland.
As a direct consequence, 31 January was also the day with the lowest emissions associated with 
peninsular electricity production since records began, with a total of 30,667 tCO2 equivalent, 
and February 2021 was the month in which CO2 equivalent emissions set all all-time minimum 
value in the peninsular electricity system, with a 23.2% decrease compared to the previous 
monthly minimum recorded in April 2020.
The coal utilisation rate in 2021 was 41%, up from 14.6% the previous year.

41
2  Electricity Generation
The Spanish Electricity System 2021
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New renewable energy records in the electricity system in 
the Balearic Islands.
The electricity produced in the Balearic Islands increased for the first time after three consecutive 
years of decreases, reaching 4,637 GWh in 2021, 31.9% more than the previous year. This is the 
highest growth since 2007.
In 2021, the installed power capacity of the power generation fleet of the Balearic Islands’ 
electricity system increased 2.3%. The installed solar photovoltaic generation capacity in the 
Balearic Islands in 2021 grew to 149 MW compared to 103 MW in 2020, representing an increase 
of 44.2%, the largest increase in renewable installed power capacity in recent years.
Annual electricity generation in 
non-peninsular systems
13,100 GWh
+10.4 %
Compared  
to 2020
In 2021, combined cycle production was lower than in 2020, especially during the first and third 
quarters of the year. In the month of February, combined cycle recorded the lowest monthly 
generation in 2021, while in contrast, in November these power stations produced 76.9% more 
than in the same month of the previous year. In addition, on Tuesday 30 November 2021, the 
all-time record for combined cycle daily generation was broken with a value of 368,131 MWh and 
on the same day between 8:00 a.m. and 9:00 a.m. combined cycle generation reached a new 
maximum hourly production value with 17,579 MWh.
The lower annual production of combined cycle power stations resulted in a reduction of their 
share in the energy generation mix of 0.8 percentage points, reaching a share of 15.2% in the 
peninsular mix in 2021 (16% in 2020). Despite this lower share, combined cycle was the third 
largest source of generation in the mix for the third consecutive year.
The utilisation rate in 2021 was 21.2% (21.8% in 2020).
Electricity generation increases in the Balearic Islands and 
the Canary Islands.
Annual electricity production in the non-mainland systems as a whole in 2021 reached 13,100 
GWh, 10.4% higher than in the previous year. The Balearic Islands registered the highest increase 
with 31.9% and in the Canary Islands production increased by 1.4%, while in Ceuta and Melilla 
production fell by 1.2% and 1.3%, respectively.

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As a consequence of this increase in installed power capacity, in 2021 renewable technologies 
reached an all-time record for annual production with 313 GWh, 32.2% higher than the 
renewable production value of the previous year. 6.8% of energy generation in the electricity 
system on the Balearic Islands came from renewable sources.
In May 2021, renewable production reached 10.6% of the Balearic Islands’ generation mix and 
on Saturday 29 May renewable generation reached its maximum value with 14% of the total 
generation. With regard to the summer months, renewable generation broke the all-time record 
high on several occasions reaching its new maximum in August with 35,020 MWh, 51.3% above 
the same month of the previous year.
Noteworthy among the renewable generation sources is the increase in solar photovoltaic,  
which in 2021 grew 58.9% to reach an all-time record with 188,247 MWh. This technology 
accounted for 4.1% of the annual production of the Balearic Islands, occupying the fourth 
position in the generation mix and overtaking coal for the first time ever.
In May 2021, solar photovoltaic facilities reached their highest monthly share ever, generating 
8.3% of the entire Balearic Islands’ mix, reaching 10.6% of all the energy generated on Saturday 
8 May. During July 2021, the highest amount of solar photovoltaic energy recorded to date was 
produced, with 22,966 MWh.
In January 2020, units 1 and 2 of the 227 MW Alcudia coal-fired power station in Majorca were 
definitively decommissioned following the drafting of the pertinent decommissioning report. In 
addition, according to Order TEC/1258/2019, from 1 January 2020, the operation of units 3 and 4 
of the Alcudia power station was limited to 1,500 hours/year until 16 August and to 500 hours/year 
as of 17 August.
The closure of units 1 and 2 of the Alcudia power station and the limitation of the operating hours 
of groups 3 and 4 led to a major change in the generation mix in the Balearic Islands, due to the 
fact that during the first 8 months of 2020 the Balearic Islands’ system did not produce electricity 
with coal and in 2021 coal-fired generation was only used in the months of June and July.
.
Annual electricity 
generation from renewable 
energy technologies
313 GWh
As a consequence of the 
increase in installed power 
capacity in 2021 in the 
Balearic Islands, renewable 
energy technologies set 
an all-time record for its 
contribution in the annual 
generation mix.
+32.2 %
Compared 
to 2020

43
2  Electricity Generation
The Spanish Electricity System 2021
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As a result, coal-fired generation in the Balearic Islands in 2021 fell by 79.9%, reaching 
an all-time low of 44 GWh. The share of coal in the Balearic Islands’ generation mix was 
only 1%, while in 2019 this technology was responsible for almost half of the production 
in the Balearic Islands, as its share was 45.2%. Coal is no longer the main source of 
generation in the archipelago, occupying the seventh position in the generation mix on 
the Balearic Islands.
 
On the other hand, diesel engines and gas turbines increased their production with 
growths of 41.3% and 6.5%, respectively. These increases in generation have favoured 
the use of diesel engines as the second source of generation in the Balearic Islands’ 
generation mix with a share of 8.6%, while gas turbines moved up to the third position in 
the Balearic Islands’ generation mix with a share of 4.8%.
In 2021, the combined cycle power stations of the Balearic Islands’ electricity system 
generated 3,482 GWh, 44.4% more than in 2020, registering the highest production 
level since 2007. This technology was the leading source of generation in the Islands’ 
generation mix, with a share of 75.1%, which represented an increase of 6.5 percentage 
points compared to the previous year.
The energy transferred from the mainland in 2021 
covered 16.1% of the Balearic Islands’ demand.
The energy transferred from the peninsula to the Balearic Islands through the HVDC 
Peninsula-Balearic Islands link covered 16.1% of the demand in the archipelago in 2021, 
reaching peaks of up to 37% of the hourly consumption, which made it possible to cover 
13% of the demand with renewable energy generation.
Demand covered with  
renewable energy generation
13 %

44
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System Report
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This increase in the amount of energy transferred from the mainland via the link to help cover 
the demand on the Balearic Islands took place mainly at the beginning of the year, with the 
highest amount being registered in February with a 31.4% share in the generation mix.
Maximum share of renewables in the Canary Islands’ 
energy mix.
Electricity production in the Canary Islands electricity system in 2021 increased by 1.4% 
compared to the previous year, reaching 8,061 GWh.
The installed renewable power capacity in the Canary Islands increased in the last year 
from 652 MW to 761 MW, representing an increase of 16.6%. This very high increase in 
installed renewable power capacity in the archipelago, particularly wind power, led to a 
review of the operating criteria for the electricity systems on the Islands, in order to ensure 
the integration of energy under safe conditions for the Canary Islands’ electricity systems. 
Specifically, the increase in installed power capacity was a result of the growth of 19.7% in 
wind power and a 9.5% rise in solar photovoltaic.
Evolution of the electricity demand coverage on the 
Balearic Islands
GWh
 Coal         
 Diesel engines         
 Gas turbine         
 Combined cycle (1)         
 Ancillary generation (2)         
 Wind             
 Solar photovoltaic         
 Other renewables         
 Cogeneration          
 Non-renewable waste         
 Renewable waste 
 Peninsula-Balearic Islands link(3)    
The net production of non-renewable and non-Hydro Management Units (HMU) facilities have their own consumption discounted. In these types of 
production, negative generation indicates that the electricity consumed for the power station’s uses exceeds its gross production. 
(1) Includes operation in open cycle mode. 
(2) Emergency generators installed temporarily in specific zones to cover a deficit in generation.
(3) Peninsula-Balearic Islands link working at the minimum technical level until 31/08/2012.
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000

45
2  Electricity Generation
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Due to this higher installed power capacity, 2021 was a year of records regarding maximum 
renewable production registered in the Canary Islands’ system. Specifically, renewable 
generation in the archipelago in 2021 was 15.4% higher than in 2020, reaching an annual 
record high of 1,606 GWh. The share of this renewable generation in the energy mix on 
the Canary Islands also beat the all-time record with a value of 19.9% compared to 17.5% 
registered the previous year.
In May 2021, this renewable generation achieved the highest share in the mix recorded to 
date with 30.7% of the energy produced that month in the Canary Islands. Regarding daily 
production, renewable energy reached a new maximum share in the Canary Islands’ generation 
mix on Sunday 23 May with 46.6%, and on Tuesday 28 September renewable generation beat 
all previous records with a value of 9,523 MWh.
The installed wind power capacity on the Canary Islands grew from 467 MW in 2020 to 560 
MW in 2021 and is the second source of generation ahead of gas turbines, diesel engines and 
steam turbines. By 31 December 2021, wind power represented 17.7% of the installed power 
capacity in the island system (15.3% in 2020). In this regard, wind power production continued 
to drive the energy transition in the archipelago and was the technology that on more occasions 
broke its own records during 2021.
May 2021 saw the highest share of this technology in the generation mix with 25.8% of the total 
produced in the Canary Islands. In addition, on Sunday 23 May wind power produced 41.8% of 
all the energy in the archipelago and on Tuesday 28 September wind power generation broke 
the all-time record with a value of 8,720 MWh.
Generation from renewable sources on the Canary Islands 
during 2021 was 15.4% higher than in 2020, setting an annual 
all-time high of 1,606 GWh.
Installed wind power capacity 
on the Canary Islands
560 MW
+19.7 %
Compared 
to 2020

46
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Throughout 2021 on the island of Gran Canaria, wind power repeatedly set new records in 
terms of instantaneous power, representing 55.9% of the demand on Tuesday 25 May at 23:55 
and on Saturday 6 November at 3:33 p.m. a new maximum value was set at 197.57 MWh.
For its part, Tenerife reached its highest record on Thursday 9 December at 3:00 p.m., 
generating 208.6 MW with wind power. Also in 2021, Tenerife’s solar photovoltaic 
generation beat its own record regarding its share in the generation mix by covering 28.6% 
of the island’s demand on Tuesday 10 August at 3:45 p.m.
The Lanzarote-Fuerteventura unified system broke its own record for instantaneous 
production using wind power technology, registering its highest ever value of 70.35 MW on 
Friday 23 July at 4:27 p.m.
On the other hand, generation from fossil fuel power stations fell by 1.5%, due to the lower 
production from diesel engines and the 20.1% decrease in the use of steam turbines, 
which in both cases registered the lowest production since 2006. Combined cycle power 
stations generated 5.4% more than in 2020 and were once again, after ten consecutive 
years, the leading technology in the generation mix with a share of 42.6%, the highest 
value recorded to date.
Evolution of the electricity generation mix on the 
Canary Islands
GWh
 Hydro         
 Diesel engines         
 Gas turbine         
 Steam turbine         
 Combined cycle (1) 
 Hidro-wind            
 Wind         
 Solar photovoltaic         
 Other renewables         
 Cogeneration
(1) Includes open cycle operation. It uses fuel oil and diesel as the main fuel.
(2) Emergency generating units that are installed temporarily in certain areas to cover a deficit in generation.
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000

47
2  Electricity Generation
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Monthly renewable integration on the island of  
El Hierro reached 48.3% for the year as a whole.
For the island of El Hierro, a particularly important electricity system due to the Gorona del Viento 
hydro-wind power station, the continuous review of its operating criteria has made it possible to 
achieve very high levels of renewable integration. Thus, in July 2021, the monthly integration of 
renewables into this system reached 81%, achieving 48.3% for the year as a whole.
Red Eléctrica is, in accordance with Law 17/2013, the company responsible for developing 
energy storage projects through pumped-storage hydroelectric power stations with 
the main purpose of helping to ensure the electricity supply, system security and the 
integration of non-manageable renewable energy in electrically isolated systems.
The Salto de Chira project is a key element to promote the energy transition in the Canary 
Islands and will allow steps to be taken toward a new, safer, more efficient, decarbonised 
and environmentally friendly energy model.
The Salto de Chira pumped-storage hydroelectric power station, being built on the island 
of Gran Canaria, was designed by Red Eléctrica and involves the development of a facility 
capable of maximising the integration of renewable energy into the electricity system 
by storing the surplus of non-manageable renewable generation that will occur when 
the production of this type of energy is high. In this way, maximum use and efficiency of 
resources is obtained and this avoids or reduces the need for non-renewable sources to 
supply electricity at times when renewable energy sources are scarce.
In addition to storing a large amount of energy, the facility, through its flexibility and 
capacity to regulate, will be able to meet the objectives that drove its design:  
the integration of renewables, system security and the guarantee of supply.
The Salto de Chira pumped 
storage hydroelectric 
power station project is  
a key element of the  
energy transition in the  
Canary Islands.
Integration of renewable 
energy on the island of 
El Hierro
48.3 %

48
Electricity 
System Report
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With an investment of more than 400 million euros, Salto de Chira includes the 
construction of a 200-MW pumped-storage hydroelectric power station (equivalent to 
approximately 36% of the peak demand of Gran Canaria) which will have an energy storage 
capacity of 3.5 GWh. Additionally, the project includes the construction of a seawater 
desalination plant and the associated marine works, as well as the necessary facilities for 
connection to the transmission grid.
The new power station will be a facility to serve Gran Canaria’s society and will promote the 
progress of society by strengthening the water-energy binomial and will integrate the four 
functions necessary to establish a sustainable and ecological development of the island, as 
it stores energy, desalinates water, cares for the territory, uses and produces clean energy 
while respecting the environment. In short, this type of facility, especially in isolated or 
weakly interconnected systems such as the Canary Islands, enables progress to be made 
towards a more sustainable and efficient energy model.
The last quarter of 2021 saw the start of both 
preliminary and construction works for the Salto de 
Chira power station.
The year 2021 has seen a milestone in the development of the project, as once the 
Environmental Impact Statement (EIS) had been obtained, which has taken into account 
the strict environmental criteria adopted in the design phase, in addition to all the rest of 
the relevant permits, the preliminary and implementation works for the construction of the 
seawater desalination plant have begun.
The processing and subsequent issuance of the EIS and the terms under which this statement 
has been drafted constitutes an endorsement of the Red Eléctrica Group’s commitment towards 
the Canary Islands society regarding sustainable development, respect for the environment and 
the conservation of biodiversity as priority axes adopted in the design of the project.
Salto de Chira  
hydroelectric power station
200 MW
+36 %
of the demand of 
Gran Canaria

49
2  Electricity Generation
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In 2021, the energy transition process marked a new milestone towards an emission-free 
model by recording a historic low in CO2 equivalent emissions associated with national 
electricity generation: 35.9 million tonnes of CO2 equivalent, 0.6% less than in 2020 and 
67.7% below the emissions recorded in 2007.
This reduction in emissions is primarily due to the significant increase in the share of clean 
energy in the national energy mix. In 2021, renewable energy sources produced 46.7% of 
national generation and technologies that do not emit CO2 equivalent accounted for 68.2% 
of the national total.
In addition, the decrease in production from coal-fired and fuel/natural gas power stations 
in the national electricity system that took place during 2021 meant that CO2 equivalent 
emissions associated with these technologies were 0.4% and 4.6% lower, respectively, 
compared to 2020.
Looking at national data since 2007, February 2021 was the cleanest month in terms of CO2 
emissions since records began with 1.8 million tonnes of CO2 equivalent and 31 January 
was the day with the lowest emissions associated with national electricity production, with a 
total of 42,995 tCO2 equivalent.
In 2021, the all-time minimum record of CO2 equivalent 
emissions associated with electricity generation was set.
Emissions and CO2eq emission factor associated 
with national electricity generation (1) 
MW
160
0.40
140
0.35
120
0.30
100
0.25
80
0.20
60
0.15
40
0.10
20
0.05
0
0.00
  Coal             
  Fuel/natural gas             
  Combined cycle            
  Cogeneration             
  Non-renewable waste 
 Emission factor (tCO2eq./MWh)
(1) Includes the Spanish Peninsula, the Balearic Islands, the Canary Islands, Ceuta and Melilla.
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
tCO2eq./MWh
tCO2eq.
Million

50
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Significant steps taken by the autonomous 
communities towards achieving the green transition.
Among the most relevant aspects of electricity generation during 2021 by autonomous 
community, the following are noteworthy:
	
— Andalusia is one of the regions 
leading the way in renewable energy in 
Spain. In 2021, generation from these 
technologies reached 55%, the highest 
annual share recorded to date. With a 
total of 16,265 GWh, 12.9% more than 
in 2020, it became the third region 
with the highest amount of green GWh 
produced in 2021, only surpassed by 
Castilla y León and Galicia.
This boost to the green transition in 
Andalusia has been possible thanks to the 
progressive renewable transformation of 
its power generation fleet. For yet another 
year, in 2021 it was the autonomous 
community with the second highest 
renewable installed power capacity in 
Spain, reaching a total of 8,609 MW of 
green energy, surpassed only by Castilla y 
León. Thus, half of the Andalusian power 
generation fleet is already renewable 
(51.3%). In 2021, Andalusia added 374 
new MW of solar photovoltaic and 44 new 
MW of wind power and decommissioned 
1,120 MW of coal-fired capacity.
The development of solar thermal in 
Andalusia is particularly noteworthy as it 
has 1,000 MW in service, and therefore 
it continues to be the leading region for 
this technology in Spain, accounting for 
43.4% of the national total.
	
— 77.4% of power generation in Aragón in 
2021 came from renewable resources, 
an increase of 20.6% over the previous 
year, driven largely by the increase 
in wind and solar photovoltaic, which 
produced 40.2% and 27.7% more than 
in 2020, respectively.
In 2021, Aragón was the Spanish 
community with the highest proportion 
of wind generation in its energy mix, 
with 53.4%, and it was the second in 
terms of production from this technology 
(10,253 GWh).
Furthermore, 2021 was the first year in 
the history of the region in which coal 
disappeared from the generation mix as 
it no longer has installed power capacity 
in the region.
	
— In Asturias, 28.6% of generation was of 
renewable origin, thanks to the boost of 
hydro and wind power, two technologies 
which, with respect to the previous year, 
increased their production by 14% and 
9.6%, respectively.
Installed power capacity, which 
reached 3,800 MW at the end of the 
year, fell by 15.8% in 2021, due to the 
decommissioning of 850 MW of coal 
power capacity. Wind power, on the 
other hand, increased its capacity in 
2021 with 139 new MW.
	
— Castilla-La Mancha is making steady 
progress in the green transition, and 
this is reflected in the data: in 2021, 
57.9% of the energy generated in 
the autonomous community was of 
renewable origin, with wind power, 
with 7,681 GWh, being the leading 
technology and generating 33.2% of the 
electricity. Solar photovoltaic increased 
its generation by 21.5% compared to 
the previous year, reaching a share of 
16.2% of the total.

51
2  Electricity Generation
The Spanish Electricity System 2021
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In 2021, Castilla-La Mancha 
consolidated its position as the 
community with the third largest 
renewable installed power capacity 
(8,140 MW), only surpassed by Castilla y 
León and Andalusia.
Wind power is the technology with the 
largest production capacity in Castilla-
La Mancha, with more than 4,000 MW, 
representing a share of 38.6% of the 
total. For its part, solar photovoltaic, with 
1,035 new MW installed during 2021, is 
the technology that has most increased 
its presence in the region’s power 
generation fleet, 53.3% more than 
the previous year. Castilla-La Mancha 
is the region with the second largest 
share of solar photovoltaic capacity in 
Spain, accounting for 19.6% of the total 
installed power capacity nationwide.
	
— Castilla y León closed 2021 as the 
autonomous community with the 
highest renewable generation in Spain: 
24,068 GWh, which accounted for 
89.1% of the region’s total production, 
an all-time maximum share since 
records began. Both generation 
and coverage in the mix were the 
highest figures in Spain in 2021, 
which consolidated Castilla y León’s 
leadership role in renewable energy 
nationwide. In 2021, 8.7% more green 
energy was produced in the region than 
in the previous year.
In 2021, wind power was the leading 
technology in the generation mix of 
Castilla y León, contributing almost 
half of the mix (49.1%). Thanks to 
this volume, it was the community 
that produced the most electricity 
from wind power (13,255 GWh). Wind 
is followed by hydro, responsible for 
32.4% and which this year generated 
9% more than in 2020. 
Furthermore, 2021 was the first time 
ever in this community in which coal 
disappeared from the generation mix as 
it no longer has installed power capacity 
in the region. 
Thus, the power generation fleet of 
Castilla y León reached 12,486 MW 
last year, of which 95.4% is renewable, 
the highest installed capacity figure in 
Spain. Wind power, with 51.1% of the 
total, is the technology with the greatest 
presence in the region and solar 
photovoltaic is the technology that has 
registered the greatest increase, putting 
174 new MW into service and increasing 
its generation capacity by 20.5% with 
respect to 2020.
	
— In Catalonia, 17% of generation came 
from renewable sources, with hydro, with 
8.5% of the total, being the renewable 
energy in Catalonia that registered the 
most GWh in 2021.
In terms of installed power capacity 
in the region, at the close of 2021, 
renewables accounted for 30.3%.
	
— Extremadura has reconfirmed its national 
leadership in solar photovoltaic energy 
in 2021, both in terms of installed power 
capacity and electricity generation. Last 
year, it installed more than 1,300 new 
MW of this technology, 51% more than 
the previous year. Thus, the region closed 
the year with more than 3,879 MW in 
service, the largest installed photovoltaic 
capacity in the country. This momentum 
allowed production from this source to 
double, reaching a volume of more than 
4,900 GWh.
The progress in photovoltaic energy 
in Extremadura enabled the region to 
close the year with a 55.9% increase 
in renewable generation compared to 
2020 data. In this regard, the share of 
green energies in the mix stood at 38%.

52
Electricity 
System Report
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All this data gives the region a 
predominant position at a national 
level in the energy transition process. 
This is possible thanks to the 
spectacular transformation of its 
power generation fleet. By year-end, 
77.8% of its installed power capacity 
was renewable. In total, more than 
7,000 MW of green power, an 
increase of 22.7% compared to the 
previous year.
	
— In 2021, 74.3% of the electricity 
generated in Galicia came from 
renewable sources, with wind as 
the number one source of Galician 
generation with 39.5%. It is followed 
by hydro, which, with 7,692 GWh was 
the second technology that produced 
the most, reaching 31.8% of the 
total. Production with this technology 
is very significant with respect to 
the rest of Spain. In fact, one out 
of every four GWh of hydroelectric 
power produced in Spain originates 
in Galicia. Once again, in 2021 wind 
and hydroelectric power together 
accounted for more than 70% of the 
region’s electricity production.
The decrease experienced by coal 
is significant, with a reduction in its 
generation of 65.8% with respect 
to 2020.
In terms of installed power capacity, 
renewables now account for 7,717 
MW and 70.5% of the total Galician 
power generation fleet.
	
— In 2021, the Balearic Islands 
experienced an important boost in 
electricity generation from renewable 
energy, consolidating the practical 
disappearance of coal in the Balearic 
Islands’ mix, initiated in 2020, thus 
confirming its progress in the energy 
transition. In this context, renewables 
on the Balearic Islands produced 
32.2% more than in 2020 and beat 
its annual record of green energy 
achieving a share of 6.7% of the total.
Efforts to advance in the green 
transition are also reflected in the 
increase in renewable production 
capacity: at the end of the year, the 
Balearic Islands had a total of 149 
MW solar photovoltaic capacity 
installed, 44.2% more than in 2020. 
In this way, renewable capacity 
accounted for 9.4% of the total 
Balearic Islands’ power generation 
fleet in 2021. 
While renewable generation grew, 
in 2021, the use of coal declined to 
become a residual energy source: 
this technology only integrated 
into the system 1% of the Balearic 
Islands’ total. This means a decrease 
of almost 80% compared to the 
previous year, when the drop in the 
use of coal was already drastic (it 
only contributed 6.3% in 2020), due 
to the hourly limitations established 
for this type of generation in the 
archipelago since December 2018 
and the reduction of its installed 
power capacity. At year-end, this 
technology accounted for only 
6.4% of the Balearic Islands’ power 
generation fleet.

53
2  Electricity Generation
The Spanish Electricity System 2021
Go to table of contents
Electricity generation/Demand ratio (%) and 
generation (GWh) in 2021 per autonomous community
   < 80 %          
   80 % to 100 %          
   101 % to  180 %          
   > 180 %
ARAGÓN
183.5 %
19,218 GWh
NAVARRA
171.9 %
8,678 GWh
CATALONIA
89.2 %
39,860 GWh
BALEARIC 
ISLANDS
83.9 %
4,637 GWh
GALICIA
138.3 %
24,211 GWh
ASTURIAS
121.6 %
11,255 GWh
CANTABRIA
42.3 %
1,693 GWh
BASQUE 
COUNTRY
42.9 %
6,814 GWh
COMMUNITY 
OF VALENCIA
66.7 %
17,924 GWh
EXTREMADURA
487.7 %
24,677 GWh
MURCIA
99.1 %
9,248 GWh
CEUTA
100 %
197 GWh 
MELILLA
100 %
205 GWh
CANARY ISLANDS
100 %
8,061 GWh
CASTILLA Y LEÓN
197.6 %
27,016 GWh
CASTILLA-LA MANCHA
192.7 %
23,129 GWh
LA RIOJA
132.3 %
2,161 GWh
MADRID
4.9 %
1,334 GWh
ANDALUSIA
74.6 %
29,586 GWh
	
— In 2021, the Canary Islands generated 
15.4% more renewable energy than 
in 2020, driven mainly by wind power 
generation, which reached its annual 
production peak (1.310 GWh) and 
accounted for 16.3% of all electricity 
in the Canary Islands.
These maximum values reached in 
the archipelago allowed renewables 
to cover almost 20% of the total, thus 
demonstrating the progress made in 
the energy transition in the Islands.
As for installed power capacity, in 
2021 it increased by 3.6% thanks to 
the commissioning of 108 new MW 
of renewable power, 92 MW of wind 
and 16 MW of solar photovoltaic. Thus, 
green energies already represent 
24.1% of the Canary Islands’ power 
generation fleet.

Electricity 
System Report
www.ree.es/en
3

55
The Spanish Electricity System 2021
Go to table of contents
For the sixth consecutive year, Spain’s electricity 
exchange programmes with other countries 
closed 2021 with an import balance.
Scheduled International 
Electricity Exchanges
Scheduled export electricity exchanges 
were 22.8% higher than in the previous 
year, while imports were 7.4% higher.
Import balance in 2021
1,462 GWh
-55.7 %
Compared 
to 2021

56
Electricity 
System Report
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The total volume of energy scheduled through the interconnections reached 34,623 GWh, 14.2% 
higher than in 2020. A total of 16,581 GWh was scheduled for export, 22.8% more than the 
previous year, and a total of 18,043 GWh was scheduled for import, 7.4% more than in 2020.  
As in the previous year, the net balance is again as an importer, with a value of 1,462 GWh, 55.7% 
less than the previous year.
In 2021, the net monthly balance of scheduled energy exchanges in the Spanish cross-border 
connections was as an importer in January and from March to October. In February, December 
and November, the net balance was as an exporter due to a higher contribution of the energy 
exchange export programmes to the French system and in the last two months of the year 
also to the Portuguese system. February was the month that registered the highest level of 
renewable energy production in the year. In November and December, high prices in France 
meant a greater contribution from export programmes to the French system, so the net balance 
was also as an exporter. The maximum net import balance took place in June (1,073 GWh) and 
the maximum export balance occurred in November (1,322 GWh).
Annual evolution of scheduled international energy exchanges
GWh
Monthly evolution of scheduled international energy 
exchanges in 2021
GWh
25,000
20,000
15,000
10,000
5,000
0
-5,000
-10,000
-15,000
-20,000
2,500
2,000
1,500
1,000
500
0
-500
-1,000
-1,500
-2,000
-2,500
  Andorra          
  France          
  Morocco          
  Portugal          
  Balance
  Andorra          
  France          
  Morocco          
  Portugal          
  Balance
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
JAN ‘21
FEB ‘21
MAR ‘21
APR ‘21   MAY ‘21 
JUN ‘21 
JUL ‘21 
AUG ‘21 
SEP ‘21 
OCT ‘21 
NOV ‘21   DEC ‘21
IMPORT
EXPORT
IMPORT
EXPORT

57
3  Scheduled International Electricity Exchanges
The Spanish Electricity System 2021
Go to table of contents
Scheduled international energy exchanges by 
cross-border connection in 2021
TWh
The total volume of energy scheduled through the 
cross-border connections reached 34,623 GWh, 
14.2% higher than in 2020.
4.1
8.7
0.5
0.3
PORTUGAL
Spain balance
18.04
16.58
EXPORTS
IMPORTS
FRANCE
ANDORRA
MOROCCO
13.4
7.4
0.2
Saldo
1.46

58
Electricity 
System Report
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FRANCE
The net annual balance of electricity exchanges through the cross-border connection with France 
was as an importer with 6,054 GWh, 15.4% higher than in 2020. Scheduled cross-border imports 
totalled 13,442 GWh, 15.2% higher than the previous year, and exports totalled 7,388 GWh, 35.6% 
higher than the previous year. With the exception of February, November and December, the net 
monthly balances were as an importer in all months.
In 2021, a high utilisation rate of this cross-border connection was registered, most of the time 
in the direction from France to Spain (62% of the hours), a figure that is similar to that of 2020. 
The average utilisation rate of the cross-border capacity during 2021 stood at 81.9%. The change 
in the direction of the balance towards an exporter is generally due to two causes: the surplus 
of renewable energy in the Spanish system or high prices in France, generally due to the high 
non-availability of its nuclear power stations. This first scenario occurred in February, where there 
were 576 hours with an export balance with an average capacity utilisation of 87.3%. The second 
scenario was the one that has occurred most in the last two months of the period, with France 
reaching a maximum hourly price of 620 €/MWh. In those last months, the average utilisation of 
exchange capacity reached a value of 80.7%.
In 2021, the cross-border connection with France 
registered a high utilisation rate, most of the time in 
the direction from France to Spain (62% of the hours), 
a figure that is similar to that of 2020.
Exchange capacity and net balance of scheduled exchanges 
at the cross-border connection with France in 2021  
MW and MWh
5,000
4,000
3,000
2,000
1,000
0
-1,000
-2,000
-3,000
-4,000
-5,000
  Balance          
  Import capacity          
  Export capacity
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC

59
3  Scheduled International Electricity Exchanges
The Spanish Electricity System 2021
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With regard to the use of energy exchange capacity, congestion was registered for 35.7% of the hours 
in the import direction, while 20% of the hours were congested in the export direction  Both of these 
values are higher than those registered in 2020. This fact confirms the lack of exchange capacity 
that exists with the European system through the existing interconnections with France. From June 
to October, the use of the cross-border connection was mainly as an importer (69% of the hours 
registered a utilisation rate above 85%), with 58% of hours being congested in the import direction. 
In February, November and December, the use was mainly as an exporter (81% of the hours) due to 
high non-availability of nuclear power in France and high renewable generation in Spain in February. 
In these months there was congestion in the export direction in 53.7% of the hours. 
The shift in the flow of the balance towards that of an 
exporter is generally due to the surplus of renewable 
energy in the Spanish system and high prices in France due 
to the high non-availability of its nuclear power stations.
Utilisation rate of exchange capacity in the 
interconnection with France in 2021
%
  Export          
  Import
100
90
80
70
60
50
40
30
20
10
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
Utilisation of the cross-border connection 
with France was in the import direction  
for a total of 5 months
69 %
The hourly utilisation 
rate for this cross-border 
connection was greater than 
85 %

60
Electricity 
System Report
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Wind power production influences day-ahead market prices and has an impact on the direction of 
energy exchanges. Thus, in the month of March, the balance of the energy exchange schedules with 
France was as an importer when low levels of wind power production were recorded in Spain, while 
the balance became mostly as an exporter when there were high levels of wind power production.
With regard to the level of utilisation of exchange capacity in the day-ahead horizon, a high rate 
of utilisation of this interconnection was recorded, slightly more than last year. Thus, in 42.3% 
of the hours it was congested in the direction from France to Spain, with an average price 
difference of 27.2 €/MWh; in 22.9% of the hours, it was congested in the direction from Spain 
to France, with an average price difference of 38.1 €/MWh, and in the remaining 34.9% of the 
hours there was no congestion in this cross-border connection.
Net scheduled balance for the cross-border connection 
with France and wind power generation in Spain
15 to 27 March 2021
MWh
Hours with and without congestion in the 
interconnection with France in 2021
%
5,000
4,000
3,000
2,000
1,000
0
-1,000
-2,000
-3,000
-4,000
20,000
16,000
12,000
8,000
4,000
0
-4,000
-8,000
-12,000
-16,000
-20,000
  Balance with France          
  Wind power generation in Spain
15M
16M
17M
18M
19M
20M
21M
22M
23M
24M
25M
26M
27M
Balance with France
Wind power generation
Import
Export
42.3 %
34.8 %
22.9 %
  Hours without congestion          
 Hours with congestion S  F          
 Hours with congestion F  S

61
3  Scheduled International Electricity Exchanges
The Spanish Electricity System 2021
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Hours with and without congestion in the 
interconnection with France and difference in 
prices of the day-ahead market in 20211
% and €/MWh
  Hours without congestion          
 Hours with congestion S  F          
 Hours with congestion F  S 
 Price differential in absolute terms (€/MWh)
100 %
50.0
90 %
45.0
80 %
40.0
70 %
35.0
60 %
30.0
50 %
25.0
40 %
20.0
30 %
15.0
20 %
10.0
10 %
5.0
0 %
0.0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
ANNUAL
In 2021, only two full days without congestion on the day-ahead horizon were recorded in 
the interconnection with France. On 70% of the days, congestion was registered for more 
than 12 hours, compared to 62% the previous year. 
The average price differential in absolute terms in 2021 was 
equal to 20.2 €/MWh, more than three times higher than 
the previous year This value is 10 times higher than the 
threshold considered by the European Union to qualify a 
cross-border connection as weak.
Congestion levels of exchange capacity on the day-ahead horizon were higher in the 
direction from France to Spain every month, except in February, March November and 
December when prices in Spain were lower than in France. It was precisely in February 
November and December that the highest percentage of hours with congestion in the 
direction from Spain to France was recorded. The highest rates of hours without congestion 
were registered in April and March (with more than half of the hours without congestion). 
It can be seen that the price differential in absolute terms is above 2 €/MWh at all times.

62
Electricity 
System Report
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Congestion rents resulting from the cross-border 
management mechanisms
€ Million
Congestions rents come 51% from auctions (20.7% from annual and 30.3% from monthly 
auctions), 47.3% from the day-ahead horizon and 1.7% from the Replacement Reserves.
With regard to the prices resulting from the exchange capacity auctions, the marginal price of 
the annual capacity auction for 2021 in the direction Spain  France was equal to 5.03 €/MW, 
which represents an increase of 48% in the price compared to the annual auction for 2020 
(3.40 €/MW). In the direction France  Spain, the resulting marginal price was equal to  
4.36 €/MW, which represents a drop of 17% compared to the price registered in this direction 
in the annual auction for 2020 (5.25 €/MW).
The maximum price of allocated capacity in the monthly auctions was registered in 
September, in the direction France  Spain with a value of 14.10 €/MW, much higher than the 
5.00 €/MW in February 2020 and very similar to the 14.05 €/MW recorded in May 2019.  
In the direction Spain  France the maximum price was reached in December with  
25.67 €/MW, more than 4 times the value registered in January 2020. 
 
The exchanges of balancing energy through the cross-border connections with France through 
the European platform for the management of balancing energy from Replacement Reserves, 
registered an import value of 340.9 GWh and an export value of 212.3 GWh. 
In 2021, it was necessary, to a much greater extent than in the previous year, for the Spanish 
and French electricity system operators to implement coordinated counter-trading actions 
(exchange programmes in the opposite direction to the existing flow established to guarantee 
the firmness of commercial programmes when faced with capacity reductions) by the operators 
of the Spanish and French electricity systems, for a total value of 1,062 GWh, a figure higher 
than the 646 GWh scheduled the previous year, thus setting a new all-time high. 35% was 
scheduled in the import direction and 65% in the export direction.
France  Spain
France  Spain
Total
Annual auction
30.6
35.3
65.8
Monthly auction
56.7
39.8
96.5
Day-ahead horizon
89.3
61.4
150.7
Replacement Reserves
3.8
1.6
5.3
Total
180.3
138.0
318.4
Congestion rents generated in 2021 in this interconnection totalled 318.4 million euros  
(180.3 million in the import direction and 138 million in the export direction), with 50% of this 
total corresponding to the Spanish electricity system. This is 135% higher than the revenue 
generated in 2020 (as a result of a 115% increase in imports and a 168% increase in exports).

63
3  Scheduled International Electricity Exchanges
The Spanish Electricity System 2021
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PORTUGAL
The net annual balance of scheduled energy exchanges in the interconnection with Portugal 
was once again as an exporter, with a value of 4,548 GWh, compared to 1,455 GWh in 2020. 
This is the third consecutive year with an export balance, previously not recorded since 2015. 
Scheduled imports totalled 4,124 GWh, showing a drop of 16.5% with respect to the previous 
year, while those for export totalled 8,673 GWh, a value that was 36% higher than last year.
The net balance of the scheduled exchanges was as an exporter except for the months of 
February and March. In the year as a whole, 65.1% of the hours registered an export balance, 
with August being the month with the highest number of hours (644). February was the month 
with the highest number of hours with an import balance (582).
Regarding the final daily use of the exchange capacity, in this interconnection there were no 
days when there was congestion throughout the whole 24-hour period.
Exchange capacity and net balance of scheduled exchanges 
in the cross-border connection with Portugal in 2021
MW and MWh
6,000
4,000
2,000
0
-2,000
-4,000
-6,000
  Balance          
  Import capacity              
  Export capacity    
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
Utilisation rate of exchange capacity in the 
interconnection with Portugal in 2021
%
  Export          
  Import
100
90
80
70
60
50
40
30
20
10
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC

64
Electricity 
System Report
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The import balances are largely due to high hydroelectric and wind power generation in 
Portugal. In 2020, the producible hydroelectric power index was 0.93 and the wind power 
index was 1.01 . February was the month with the highest import balance, being the month 
with the highest producible hydroelectric power index and the second highest in the wind 
power index in the Portuguese system. October, July and December were the months with 
the fewest hours of congestion (1 hour in October, 4 hours in July and 5 hours in December).
Both hydroelectric and wind power generation significantly influenced the scheduled 
balances in the interconnection with Portugal. As an example, it can be seen how in a 
month with high wind and hydroelectric power production in Portugal (such as February), 
the balance is as an importer, while in months with low production it is as an exporter, or 
with a low importer balance. 
In the day-ahead horizon, the convergence levels registered in the interconnection 
with Portugal in 2021 were high, resulting in a percentage of hours with congestion in 
the day-ahead market of slightly lower than 3%. Consequently, prices in one system or 
the other were very similar, with the hourly price differential in absolute terms being 
0.20 €/MWh.
Balance of scheduled exchanges for the  
cross-border connection with Portugal and wind 
power generation in Portugal
February 2021
MWh
7,000
6,000
5,000
4,000
3,000
2,000
1,000
0
-1,000
-2,000
-3,000
  Balance with Portugal          
  Wind power generation in Portugal          
  Wind power + hydroelectric generation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Portugal  Spain
Spain  Portugal

65
3  Scheduled International Electricity Exchanges
The Spanish Electricity System 2021
Go to table of contents
Hours with and without congestion in the 
interconnection with Portugal in 2021
%
97.4 %
1.3 %
1.3 %
  Hours without congestion          
 Hours with congestion S  P          
 Hours with congestion P  S
Monthly congestion levels and difference in prices 
in the interconnection with Portugal in 2021
% and €/MWh
  Hours without congestion          
 Hours with congestion S  P          
 Hours with congestion P  S 
 Price differential in absolute terms (€/MWh)
100 %
0.60
90 %
0.54
80 %
0.48
70 %
0.42
60 %
0.36
50 %
0.30
40 %
0.24
30 %
0.18
20 %
0.12
10 %
0.06
0 %
0.00
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
ANNUAL
The monthly evolution shows that August and October were the months with the highest 
coupling rate, while January saw the highest percentage of hours with congestion, with 
almost 8% of the hours of the month and a price difference of 0.58 €/MWh, which is the 
highest price difference ever registered. September, with slightly more than 2% of the hours 
with congestion, is the month with the second largest price difference (0.42 €/MWh).

66
Electricity 
System Report
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Congestion rents resulting from the cross-border 
management mechanisms with Portugal
€ Million
Congestion rents reached 4 million euros, with 56.9% coming from the day-ahead market, 
3% from the intraday market, 1.9% from Replacement Reserves and 38.2% from the auctions 
(13.6% in the annual, 7.5% in the quarterly and 17.1% in the monthly). 50% of this amount 
corresponds to the Spanish electricity system.
A total of 526.5 GWh of imports and 572 GWh of exports were allocated through the European 
platform for the management of balancing energy from Replacement Reserves.
In 2021, coordinated counter-trading actions were required for a total of 7.3 GWh, lower 
than the 14.2 GWh programmed in the previous year. In the import direction, 94.7% were 
programmed in the import direction and the remaining 5.3% were in the export direction.
Portugal  Spain
Spain  Portugal
Total
Annual auction
0.25
0.30
0.54
Quarterly auction
0.12
0.18
0.30
Monthly auction
0.40
0.28
0.68
Day-ahead coupling
0.60
1.67
2.28
Intraday market
0.07
0.04
0.12
Replacement Reserves
0.01
0.07
0.08
Total
1.46
2.54
4.00
Congestion rents reached 
4 million euros, with 
56.9% coming from the 
day-ahead market, 3% 
from the intraday market, 
1.9% from Replacement 
Reserves and 38.2% from 
the auctions.
Implementation  
of coordinated  
counter-trading actions
7.3 GWh
-48.6 %
Compared 
to 2020

67
3  Scheduled International Electricity Exchanges
The Spanish Electricity System 2021
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MOROCCO
The annual balance of the scheduled exchanges with Morocco was again as an importer 
this year, with a value of 182 GWh, compared to 298 GWh exported last year. The months of 
February, July to September and November showed a net balance as an exporter, while the 
rest of the months the net balance is as an importer. The total volume of energy exchanged 
was 772 GWh, 11.7% more than last year, but far from the values of other years. 
The average utilisation rate of the exchange capacity of this interconnection changed last 
year, exporting 14% in 2021 compared to 24% the previous year, while imports stood at 
24% compared to 13% the previous year. The interconnection was used for only 38.1% of 
the hours, compared to 37,1% the previous year.
The average utilisation of the interconnection two-way energy flows (import-export) in 2021 
was 13.9% while in 2020 it was 12%. If only days are taken into account when scheduled 
exchanges were programmed, the average utilisation rate in 2021 was 36.5%, compared to 
32% in 2020, but still far from the 50.5% registered in 2019.
Exchange capacity and net balance of scheduled 
exchanges in the interconnection with Morocco in 2021
MW and MWh
800
600
400
200
0
-200
-400
-600
-800
-1,000
  Balance          
  Import capacity              
  Export capacity 
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC

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The following graph clearly shows that the daily interconnection exchange capacity with 
Morocco in 2021 was only congested for 2 hours in the import direction (capacity reduced 
to 400 MW), while in the previous year the interconnection was not congested at any time, 
and in 2019 it was congested for 18 hours in the import direction and for 12 hours in the 
export direction.
The reductions in the exchange capacity through this cross-border connection were due 
to the non-availability of one of the two links that make up this interconnection that had a 
significant impact on exchange capacity. For 287 hours (3.3% of the hours) the exchange 
capacity was 0 MW due to the unavailability of both links. In 1,607 hours (18.3% of the 
hours) the capacity on this interconnection was limited to 400 MW in both directions, as 
one of the circuits was inoperative. 
Although the energy traded through this interconnection was slightly higher than last year, 
there was a significant reduction compared to previous years, which shows that Morocco is 
becoming more and more self-sufficient, with a consequent reduction in the energy traded 
through this border.
Daily interconnection capacity utilisation in the cross-
border connection with Morocco in 2021 
%
Evolution of the volume of scheduled energy at the 
cross-border connection with Morocco
GWh
  Export          
  Import
100
90
80
70
60
50
40
30
20
10
0
70
60
50
40
30
20
10
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
JAN MAR MAY JUL SEP NOV JAN MAR MAY JUL SEP NOV JAN MAR MAY JUL SEP NOV JAN MAR MAY JUL SEP NOV JAN MAR MAY JUL SEP NOV
2017
2018
2019
2020
2021

69
3  Scheduled International Electricity Exchanges
The Spanish Electricity System 2021
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A change in trading was also observed. The following table shows trading in the day-ahead 
markets (DM) and intraday markets (IM), in GWh and the % traded in each market with 
respect to the total volume scheduled.
It can be clearly seen how a greater volume of energy has usually been managed in the 
intraday market, although in the first years shown in the table, the IM values ranged 
between 40-60%; in 2018 it changed, with just over 70% of the energy traded in the 
intraday market; in 2019 it was 90%, in 2020 there was 100% traded in this market and in 
2021 the value stood at 97%.
The monthly invoicing of access tolls for the Moroccan interconnection registered a total 
income of 4.1 million euros, 8.5% lower than last year’s value.
Monthly invoicing for access tolls for the Andorran interconnection totalled 1.6 million 
euros, 35.5% higher than the previous year.
ANDORRA
The annual balance of the electricity exchanges scheduled in the interconnection with 
Andorra was as an exporter, with a value of 225 GWh, which represented an increase of 
15.1% with respect to 2020. The average utilisation rate of the exchange capacity of this 
interconnection in the export direction was 17.9% compared to 18.5% the previous year.
%MI
%MD
MD Contracted
MI Contracted
Scheduled volume
2017
58%   
42%   
2,389        
3,352        
5,747       
2018
73%    
27%    
986       
2,653       
3,640       
2019
90%   
9%    
124       
1,211       
1,351       
2020
100%    
0%    
0       
691        
691        
2021
97%   
3%   
20        
749       
772       
Exchange capacity and net balance of scheduled 
exchanges in the interconnection with Andorra in 2021
MW and MWh
150
10
50
0
-50
-100
-150
  Balance          
  Import capacity              
  Export capacity 
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC

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4

71
The Spanish Electricity System 2021
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In 2021, the transmission grid continued to be 
strengthened, increasing investment in the grid 
to 391 million euros, 2.1% higher than in the 
same period of the previous year.
Electricity 
Transmission 
206 km of line circuit and 134 
substation bays were commissioned 
in 2021, bringing the total length of 
line circuit in the national transmission 
grid to 44,769 km, an increase of 0.5% 
compared to 2020.
Installed transformer 
capacity nationwide
93,871 MVA
Total length of line circuit 
in the national grid 
44,769 Km

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In 2021, in a context still impacted by the pandemic, the transmission grid continued to 
be strengthened, increasing investment in the grid to 391 million euros, 2.1% higher than 
in the same period of the previous year. In this regard, facilities were commissioned that 
contribute to help integrate as much renewable generation as possible, improve grid 
meshing and promote electrification, to guarantee the security of supply and the levels of 
service quality.
There were 206 km of line circuit and 134 substation bays commissioned in 2021, bringing 
the total length of line circuit in the national transmission grid to 44,769 km, an increase 
of 0.5% compared to 2020. In regard to transformer capacity, this increased by 850 MVA, 
bringing the total transformer capacity nationwide to 93.871 MVA (an increase of 0.9% 
compared to 2020).
Electricity transmission grid facilities in Spain
400 kV
   
 ≤ 220 kV
Peninsula
Peninsula
Balearic Islands 
Canary Islands
Total
Total line circuit (km)
21,768
19,493
1,929
1,578
44,769
Overhead lines (km)
21,651
18,702
1,141
1,237
42,731
Submarine cable (km)
29
236
582
30
877
Underground cable (km)
88
556
206
311
1,161
Transformer capacity (MVA)
84,790
1,363
3,838
3,880
93,871
Provisional data pending audit (currently underway).
Cumulative figures regarding kilometres of line circuit and for transformer capacity as at 31 December 2021.
Evolution of the electricity transmission grid in Spain 
km of circuit
  Peninsula ≤ 220 kV          
  Balearic Islands ≤ 220 kV          
  Canary Islands ≤ 220 kV          
  Peninsula 400 kV
Provisional data pending audit (currently underway).
Cumulative figures regarding kilometres of line circuit as at 31 December of each year. Includes the transmission grid assets of those utility 
companies whose electricity distribution facilities are considered as an integral part of the overall transmission grid infrastructure nationwide.
25,000
20,000
15,000
10,000
5,000
0
2017
2018
2019
2020
2021 (1)
44,015
44,264
44,446
44,563
44,769

73
4  Electricity Transmission 
The Spanish Electricity System 2021
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Among the projects carried out in 2021 in the transmission grid, the following are noteworthy 
and are listed according to the geographical area in which the work was carried out: 
	
— Andalusia: The Gabias-Orgiva, the Arroyovalle-
Montecillo Bajo and the Cártama-Los Montes 
220 kV lines had their power transmission 
capacity increased to provide greater security 
of supply in the area and provide support for 
the distribution network. The enlargement 
works for the 220 kV Torrearenillas line were 
carried out and the 220 kV El Zumajo (Nueva 
Parralejo) substation was commissioned 
to contribute to the resolution of technical 
constraints, provide support for the distribution 
network, evacuate renewable energy 
generation, and improve security of supply.
	
— Aragón: Progress continued on the bolstering of 
the transmission grid around the metropolitan 
area of Zaragoza with the commissioning of the 
200 kV Los Leones-Villanueva double circuit line. 
In addition, the new 400 kV Cariñena substation 
and its incoming/outgoing feeder lines for the 
400 kV Almazán-Fuendetodos line will enable 
the Zaragoza-Teruel high‑speed railway axis to 
be powered. On the other hand, progress was 
made in strengthening the transmission grid in 
different areas with the commissioning of the 
220 kV Mezquita‑Valdeconejos and the 220 kV 
Valdeconejos-Escucha lines, and the 220 kV 
T Foradada-Escalona, the 220 kV Escalona-T 
Escalona and the 400 kV Aragón-Mequinenza lines 
had their power transmission capacity increased.
	
— The Balearic Islands: Noteworthy was the 
enlargement of the 132 kV Bossa substation to 
improve the security of supply in the area and of 
the 66 kV San Martin and the 132 kV Ciudadela 
substations, which will enable the evacuation of 
renewable energy generation.
	
— The Canary Islands: The new 220/66 kV 
El Rosario (Nueva Geneto) substation was 
commissioned, which together with the two 
250 MVA combined capacity transformers, 
will improve the security of supply in the 
northern area of Tenerife. In Fuerteventura, the 
integration of renewable generation has been 
improved with the enlargement of the 66 kV 
Puerto del Rosario substation. Finally, on the 
island of Gran Canaria, the 66 kV Barranco de 
Tirajana dual node has been enlarged, which will 
improve the security of supply in the area.
	
— Castilla La Mancha: To promote the evacuation 
of renewable energy, the 220 kV Torrijos, the 
220 kV Villares de Saz and the 400 kV Olmedilla 
substations were commissioned, continuing 
with the ambitious plan for the integration of 
this type of energy in the area. Similarly, and 
to facilitate the transit of energy flows through 
the area, works were completed to increase 
the power transmission capacity of the 220 kV 
Villares del Saz-Olmedilla1 line.
	
— Castilla y León: Construction work continued 
on the 400 kV Tordesillas-Galapagar-San 
Sebastián de los Reyes (SUMA) axis for the 
meshing between Castilla y León and Madrid, 
in the section between Segovia and the 
Community of Madrid. Similarly, in order to 
increase the security of supply, the 220 kV T 
Renedo was dismantled and the new 220 kV 
Renedo-Mudarrita line was commissioned. 
Lastly, the enlargement of the 220 kV Zamora 
substation was completed to promote the 
generation of renewable energy.
In 2021, 16 new substation bays were commissioned to 
increase the overall renewable power capacity. Noteworthy 
are those in the Almaraz, Brovales and Carmonita substations, 
with a capacity that ranges between 0.7 and 1 GW.

74
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— Catalonia: The 220 kV Begues and Puigpelat 
substations were enlarged to facilitate support 
for the distribution networks, industrial 
consumers and to contribute to the resolution 
of technical constraints. On the other hand, 
progress was made in the development of the 
220 kV grid by commissioning the enlargement 
of the Hospitalet substation that will connect up 
to the future Cerdá substation.
	
— Extremadura: Special mention should be 
made of the new 600 MVA transformer in the 
400 kV Almaraz CN substation, which will 
increase support to the distribution network 
and contribute to the resolution of technical 
constraints in the area. The 220 kV Jose 
María Oriol substation received a new reactor, 
which will improve voltage control in the area. 
Similarly, the new 220 kV Arenales substation 
with its connection to the 220 kV Jose María 
Oriol substation was commissioned and work 
continued to connect this substation with 
the 220 kV Cáceres and the 220 kV Trujillo 
substations. Lastly, the 66 kV Riocaya-Alcaçova 
interconnection line has replaced the previous 
66 kV Badajoz-Alcaçova line, and the new 400 
kV Carmonita substation was completed, along 
with the incoming/outgoing feeder lines for the 
400 kV Almaraz CN-San Serván line,  
which will facilitate the supply of the  
Toledo-Cáceres-Badajoz railway axis and 
improve the evacuation of renewable energy.
	
— Levante: The commissioning of the  
new 400 kV Montesa substation  
and its incoming/outgoing feeder lines  
for the 400 kV Benejama-Catadau line  
has enabled the powering of the  
Albacete-Alicante-Valencia railway axis.  
In the Murcia region, the enlargement of the 
400 kV Carril substation will promote the 
integration of new renewable generation.
	
— The central area: Progress was made on the 
actions proposed in the 2015-2020 Planning 
regarding permitting processes and works.
	
— The northern area: In the Basque Country, 
the construction of the 400 kV Güeñes-Ichaso 
double circuit line continued, noteworthy 
being the commissioning of the enlargement 
of the 400 kV Ichaso substation.  
This action is part of the axis that will 
connect the west of the Basque Country 
(Abanto-Güeñes axis) with the 400 kV grid 
in Navarra (Muruarte-Castejón axis) and 
will increase the evacuation of renewable 
generation and ensure the committed 
values of exchange capacity between 
Spain and France are met. In Cantabria, 
construction continued on the 220 kV line 
between Astillero and Cacicedo, which 
will significantly strengthen the security of 
supply in the entire city and the port area 
of Santander. Works were completed for 
the increase in the power transmission 
capacity of the 220 kV Garoña-Puentelarrá 
and the 220 kV Cillamayor-Mataporquera 
lines, which will allow greater integration 
of renewable energy and will mean an 
improvement in the resolution of technical 
constraints in the area. In Galicia,  
the new 220 kV Tomeza substation was 
commissioned in order to help power the 
high-speed train, with connections to the 
220 kV Lourizán-Pazos and the 220 kV 
Lourizán-Tibo lines. Lastly, to increase the 
connection of renewable generation, the 
new 220 kV Lousame-Mazaricos line was 
commissioned. 
For the connection of railway 
axes, new substation bays were 
commissioned at the Carmonita 
substation (Plasencia-Badajoz 
axis), Tomeza substation 
(La Coruña-Vigo line), Montesa 
substation (Játiva-La Encina line)  
and Cariñena substation 
(Zaragoza- Zaragoza line).

75
4  Electricity Transmission 
The Spanish Electricity System 2021
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INTERNATIONAL CROSS-BORDER CONNECTIONS
Cross-border connections continue to be key elements in the energy transition in order 
to achieve greater integration of renewable energy and to advance along the road to 
decarbonisation. The strengthening of interconnections will continue to be a priority in the 
development of the transmission grid in the coming years.
The last interconnection commissioned between Spain and France (Baixas-Santa Llogaia) 
at the end of 2014 doubled the electricity exchange capacity between Spain and France 
(from 1,400 MW to 2,800 MW), which has contributed to strengthening the security of the 
two electricity systems and to boosting the integration of a greater volume of renewable 
energy. However, despite this increase, the degree of interconnection of Spain still 
continues to be far below the targets set by the European Union of 10% and 15%,  
for 2020 and 2030, respectively.
Spain’s National Energy and Climate Plan (NECP) 
makes this clear and proposes increasing the 
exchange capacity with Portugal up to 3,000 MW 
and up to 8,000 MW with France, by means of 
three new electricity interconnections.  
The interconnection between Gatika (Spain) 
and Cubnezais (France) will basically be the first 
underwater interconnection between Spain and 
France (‘Bay of Biscay’ project), and there are two 
other projects via the Pyrenees(1).
Spain’s National Energy and Climate Plan (NECP) proposes 
increasing the exchange capacity with Portugal up to 
3,000 MW and up to 8,000 MW with France, by means of 
three new electricity interconnections.
(1) The three projects were endorsed by the Heads of State and the Governments of Portugal, Spain and 
France, as well as by representatives of the European Commission (EC) and the European Investment 
Bank (EIB) within the framework of the two Summits on cross-border connections held in 2015 (Madrid 
Declaration) and in Lisbon in 2018 (Lisbon Declaration). The three projects are included in the 5th list of 
Projects of Common Interest (PCIs), adopted by the European Commission on 19 November 2021. This list 
is to be approved through the Commission Delegated Regulation after the deadline for scrutiny by the  
co-legislators (Parliament and Council). For the time being, the European Parliament already gave its 
approval on 9 March after an objection was rejected.
2030 European Union Target
15 %
interconnection exchange capacity 
over the total installed capacity nationwide

76
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System Report
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SERVICE QUALITY
The service quality indicators for 2021 remain within the acceptable values set out in Royal 
Decree 1955/2000.
The key performance indicators of global quality according to Royal Decree 1955/2000 are 
Average Interruption Time (AIT) and Energy Not Supplied (ENS).
In the peninsular electricity system, 17 supply interruptions were registered in 2021, 42% 
more than in 2020. This rise is reflected in the increase in the ENS compared to the 
previous year (188 MWh in 2021 compared to 95 MWh in 2020). Similarly, an AIT value of 
0.41 minutes was recorded (0.21 minutes in 2020), despite this result, it is still well below 
the reference value of 15 minutes established in article 26.2 of Royal Decree 1955/2000. 
The main incident occurred at the 220 kV Dos Hermanas facility with an ENS of 81 MWh.
In the Balearic Islands electricity system, the continuity of supply indicators for 2021 also 
showed a clear improvement over the previous year. One supply interruption was recorded, 
resulting in an ENS of 1 MWh (4 MWh in 2020) and an AIT of 0.07 minutes (0.47 minutes in 
2020). Something similar occurred in the Canary Islands’ electricity system, with an ENS of 
33 MWh (corresponding to 4 supply interruptions) and an AIT of 2.33 minutes. 
The quality of the transmission grid is also assessed on the basis of the availability of 
its facilities. Availability measures the capacity or possibility of use by the system of 
the various elements of the transmission grid, these being the electricity line circuits, 
transformers and active or reactive power control elements (reactors and capacitors).  
The availability rate is calculated as the difference between 100 and the non-availability 
rate of the transmission grid.
Energy not supplied (ENS) and average 
interruption time (AIT) of the transmission grid
ENS (MWh)
   
 AIT (minutes)
Peninsula
Balearic Islands    
Canary Islands
Peninsula
Balearic Islands   
Canary Islands
2017 
60 
33      
47      
0.13 
2.88    
2.75    
2018 
250 
38     
63     
0.52 
3.27    
3.77    
2019 
47 
1      
2,626     
0.10 
0.09 
155.52    
2020 
95 
4      
65     
0.21 
0.47     
4.29    
2021 (1)
188 
1     
33      
0.41 
0.07     
2.33     
ENS: Energy not supplied. AIT: Average interruption time.
Average Interruption Time (AIT) = Energy Not Supplied (ENS) / Average System Power. 
(1) Provisional data pending audit (currently underway).

77
4  Electricity Transmission 
The Spanish Electricity System 2021
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The following graphs show the evolution of the non-availability rate indicator over the last five years. The availability 
rate of the peninsular transmission grid in 2021 reached a value of 98.50%, slightly lower than the rate of 98.57% 
registered in 2020. In the Balearic Islands and the Canary Islands systems, the grid availability rate stood at 
98.61% (98.66% in 2020) and 99.20% (99.07% in 2020) respectively. In general, 2021 showed an increase in the 
non-availability rate due to preventive and predictive maintenance carried out during the year, which contrasts with 
the decrease in scheduled non-availability of facilities as a result of improvement actions carried out on grid assets.
Annual evolution of the non-availability rate of the 
peninsular transmission grid 
%
Annual evolution of the non-availability rate of the 
Balearic Islands transmission grid 
%
Annual evolution of the non-availability rate of the 
Canary Islands transmission grid 
%
 Programmed for predictive and preventative maintenance         	
 Programmed for causes not due to maintenance 
 Non-programmed due to corrective maintenance             	
 Non-programmed due to fortuitous circumstances
Note: Classification according to RD 1955/2000. 
The total non-availability rate of the transmission grid does not include non-availabilities due to force-majeure or third-party actions. 
(1) Provisional data pending audit (currently underway).
4
3.5
3
2.5
2
1.5
1
0.5
0
4
3.5
3
2.5
2
1.5
1
0.5
0
4
3.5
3
2.5
2
1.5
1
0.5
0
2017
2018
2019
2020
2021 (1)
2017
2018
2019
2020
2021 (1)
2017
2018
2019
2020
2021 (1)
1.71
1.86
1.76
1.43
1.50
2.15
3.18
2.65
1.34
1.39
1.88
1.21
1.10
0.93
0.80

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5

79
The Spanish Electricity System 2021
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The average final price of energy registered 
an all-time high in 2021. It is almost triple that 
of last year and doubles the figures registered 
between 2017 and 2019.
Electricity Markets 
The average final energy price in 
the electricity market in 2021 was  
118.65 €/MWh, the highest  
price ever. 
Impact of the day-ahead and  
intraday market on the composition  
of the final price of energy
95.3 %
FINAL ENERGY 
IN THE ELECTRICITY 
MARKET
+ 2.4 %
Compared 
to 2020

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In 2021, the total energy managed in the electricity market (reference supply plus free 
contracting) was 2.4% higher than the previous year.
The average final energy price in the electricity market in 2021 was 118.65 €/MWh, the highest 
price ever. The previous all-time high was registered in 2008 when it reached a value slightly 
below 70 €/MWh, with the price this year being 70.6% higher. This is nearly triple the price 
registered in 2020 and double that of the figures registered between 2017 and 2019.
A month-on-month comparison shows that, with the exception of February, prices were higher than in 
the same months of the previous year. The previous year, due to the pandemic, prices were very low from 
March to June, registering an all-time monthly low in April, but the biggest increases compared to the 
previous year did not occur in these months, but in the last four months of the year. In those last months 
of the year, the variation was more than 200% compared to the same month of the previous year.
Components of the average final price of energy
€/MWh
Components of the average final price of energy in the 
electricity market
€/MWh
140
120
100
80
60
40
20
0
300
250
200
150
100
50
0
  Day-ahead and intraday market          
  Ancillary services          
  Capacity payments          
  Interruptible Load Program
  Day-ahead and intraday market        
  Ancillary services        
  Capacity payments        
  Interruptible Load Program      
  Average final price
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
2020
2021

81
5  Electricity Markets 
The Spanish Electricity System 2021
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The weight of the day ahead and intraday market component increased in 2021, reaching 
95.3%, which is the highest percentage ever, surpassing the 94.8% of 2008. The share 
of ancillary services represents 3.6%, very similar to that of 2018 and below the 6.3% 
registered in 2020. The share of capacity payments represents only 1.1%, much lower than 
in previous years, and only comparable to the 1.5% in 2008.
Comparing the impact of the price on demand served showed that the price of the day-ahead 
and intraday market almost tripled compared to the previous year, the price of ancillary 
services increased by 68.5% and capacity payments were reduced by almost 51%.
Components of the average final price of energy in 
the electricity market in 2021
€/MWh
The weight of the day ahead and intraday market 
component increased in 2021, reaching 95.3%, which is the 
highest percentage ever, surpassing the 94.8% of 2008.
Day-ahead and intraday market 
113.09 €/MWh 
95.3 %
Capacity payments  
1.30 €/MWh 
1.1 %
Secondary  
control energy
1.08 €/MWh 
0.9 %
Other 
1.35 €/MWh 
1.1 %
Ancillary services 
4.26 €/MWh 
3.6 %
Daily base operating 
schedule (PDBF)  
technical constraints 
1.83 €/MWh 
1.6 %

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DAY-AHEAD MARKET
Energy in the day-ahead market stood at 248 TWh in 2021 (176 TWh in the spot market without 
bilateral contracts), an increase of 2.9% compared to 2020. 71.1% of energy was traded in the 
spot market and the remaining 28.9% through bilateral contracts, the same values as those 
registered in the previous year. These percentages have remained quite similar since 2015.
The share of energy supplied by market traders who are not classified as reference 
suppliers grew slightly this year, reaching a market share of 89% in 2021, compared to 
88.2% in the previous year. The share is very similar to that registered in 2019.
Evolution of purchases in PDBF from Reference 
Traders (RT) and Other Traders (OT)
TWh
Percentage of energy purchased in the day-ahead 
market and through bilateral contracts
%
300
250
200
150
100
50
0
  OT-bilateral          
  OT-day-ahead          
  RT-bilateral          
  RT-day-ahead          
The share of energy supplied by market traders who are not classified as reference suppliers grew slightly this year, reaching a market 
share of 89% in 2021, compared to 88.2% in the previous year. The share is very similar to that registered in 2019. 
2017
2018
2019
2020
2021
88.2 %
11.8 %
88.2 %
11.8 %
88.5 %
11.5 %
88.8 %
11.2 %
89.0 %
11.0 %
Bilateral contracts  
28.9 %
Spot market  
71.1 %

83
5  Electricity Markets 
The Spanish Electricity System 2021
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The average day-ahead electricity market price in 2021 was 111.93 €/MWh, the highest ever, 
much more than the maximum value registered in 2008 (76 €/MWh). The price is more 
than triple that of last year’s price (which was very low due to the pandemic). This price 
increase, shown in the graph, which was mainly as of August, actually started earlier with 
prices already above 90 €/MWh as of the end of May.
The year began with high values in January, but in February they were quite low, the 
following months, although high, were stable, and as of August, they had been rising 
steadily, registering a small fall in November and in the last few days of the year.
It can be seen in the graph how the minimum prices were quite high. Worth highlighting was 
the month of September, whose minimum hourly value was almost 100 €/MWh. In the graph 
we can see how prices were rising, repeatedly exceeding the maximum registered values 
until, on 23 December it reached the all-time daily maximum all-time high (383.67 €/MWh) 
and the hourly record (409.00 €/MWh between 7:00 pm and 8:00 pm).
Evolution of maximum and minimum prices in the 
day-ahead market 
€/MWh
  2020          
  2021
450
400
350
300
250
200
150
100
50
0
01/01 15/01 29/01 12/02 26/02 12/03 26/03 09/04 23/04 07/05 21/05 04/06 18/06 02/07 16/07 30/07 13/08 27/08 10/09 24/09 08/10 22/10 05/11
19/11 03/12 17/12
31/12
Average day-ahead  
electricity market price
111.93 €/MWh
230 %
Compared 
to 2020

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As of April monthly prices set all-time highs and June registered the all-time monthly 
maximum since the start of the market. As of June, each month saw a new monthly record 
high, with the exception of November, finishing the month of December with a monthly 
record high of 239.16 €/MWh. However, February’s price was low, the eighth lowest price 
ever registered for the month of February.
If we take into account the generation mix in the day-ahead market, an important factor in 
the calculation of the price, it can be seen that the month of February 2021 was the month 
with the lowest price, as it was the month with the highest share of renewables and with 
the lowest share of combined cycle.
The share of renewable energy in the electricity generation mix for the energy matching process 
for 2021 was 62.6%, up from 57.6% the previous year. Nuclear saw its share in the mix reduced 
by 2.1 percentage points, as this year more energy was again managed through bilateral 
contracts, whereas during the pandemic much less was negotiated via bilateral contracts (down 
1.7 percentage points in 2020 compared to the previous year). The share of combined cycle 
decreased by 2.1 percentage points, while that of coal increased slightly (0.8 percentage points). 
Wind and solar increased by 1.3 and 3.1 percentage points, respectively. This scenario would 
have led us to expect a reduction in prices, however, this was not the case. 
Generation structure in the matching process and 
price of the day-ahead market and of natural gas
% and €/MWh
100 %
250
90 %
225
80 %
200
70 %
175
60 %
150
50 %
125
40%
100
30%
75
20%
50
10%
25
0
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
  Hydro          
 Pumped storage (net supply)              
 Nuclear            
 Coal            
 Combined cycle            
 Wind           
 Solar photovoltaic          
 Solar thermal          
 Other renewables          
 Cogeneration          
 Non-renewable waste          
 Renewable waste          
 Average day-ahead price          
 Price of natural gas using 2011 as a base year
2020
2021

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Evolution of the price of fuel and CO2 emissions
Another factor influencing the price is fuel reserves. These were above historical average 
levels until April. In February, reserves almost reached their maximum levels, a situation 
that also influenced the fall in prices in that month. In the last few months of 2021, fuel 
reserves were below the average values, which caused an increase in prices.
The increase in the market price during most of 2021 was mainly due to the increase in fuel 
prices and for CO2 emissions.
The graph below shows the sharp increase in fuel prices. The price of European natural gas, 
after reaching its lowest price ever in May 2020 (during the pandemic), began to rise which 
led it to repeatedly reach the highest prices since August, with the exception of November, 
reaching a value of 129.65 $/MWh in December, a value which is much higher than the 
19.97 €/MWh in December 2020. The price of coal followed a similar trend, reaching its 
maximum prices in October, as after the fall in November (stronger than that of gas) prices 
did not reach the maximum again. The price of Brent Crude Oil, which during the pandemic 
was also low, reached values that had not been seen since 2002, increasing throughout 
the year and exceeding the values of 2018, but this was still far from the prices recorded 
between 2011 and 2014.
With regard to the price of CO2 emissions, a slight fall was recorded from March to May 
2020, which was below the values registered the previous year, and then it began to rise 
and repeatedly beat the all-time monthly maximum prices as of December 2020. The 
annual price was 120% higher than in 2020 and 119% higher than in 2019.
  Brent Crude Oil ($/BBL)          
  Coal ($/MT)          
  Natural Gas – Europe ($/MWh)           
  Emissions ($/tCO2)
210
180
150
120
90
60
30
0
JAN´13 MAY´13 SEP´13 JAN´14 MAY´14 SEP´14 JAN´15 MAY´15 SEP´15 JAN´16 MAY´16 SEP´16 JAN´17 MAY´17 SEP´17 JAN´18 MAY´18 SEP´18 JAN´19 MAY´19 SEP´19 JAN´20 MAY´20 SEP´20 JAN´21 MAY´21 SEP´21

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Generation mix in the Day-Ahead Market (DAM) 
energy matching process in 2021 (annual minimum 
and maximum hourly price)
%
If the energy matching process of the generation mix is represented in a graph showing 
the times of the day in which the day-ahead market price set the annual minimum and 
maximum values, it can be seen how these are quite different. Regarding the time of day at 
which the minimum price was set, it can be seen how wind power was the technology that 
had an impact on the marginal price (with a percentage higher than 43%), with renewable 
energy matched at that time being nearly 80%. Looking at the mix during the hour of the 
day in which the maximum price was registered, it can be seen that hydro determined the 
marginal price, although it was combined cycle that had the highest percentage in the mix 
(around 35%). At that time of the day, renewables represented a share of just under 40% of 
the generation mix. On that day, the greatest volume of energy matched with prices close to 
the marginal price corresponds to combined cycle followed by hydro.
The maximum day-ahead price was recorded on 23 December (383.67 €/MWh) and the 
minimum on 31 January (1.42 €/MWh). 
	
Minimum price	
Maximum price
Hydro	
4.3 %	
11.6 %
Pumped storage (net supply)       	0 %	
7.7 %
Nuclear	
4.9 %	
3.4 %
Coal	
0 %	
0.4 %
Combined cycle	
0 %	
35.9 %
Wind	
44.5 %	
21.9 %
Solar photovoltaic 	
25.6 % 	
0.2 %
Solar thermal 	
2.7 % 	
0 %
Other renewables 	
2.4 % 	
2.6 %
Cogeneration 	
13.5 % 	
15.0 %
Non-renewable waste 	
1.5 % 	
0.9 %
Renewable waste 	
0.6 % 	
0.4 %
Minimum price (DAM) 
9 May (4:00 pm) 
Maximum price (DAM) 
23 Dec (7:00 pm)
  Energy technology that sets the marginal price

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European prices recorded the same behaviour as those of Spain, all setting annual and 
monthly record highs. A comparison between the Spanish day-ahead market price and 
the European market prices shows that prices in Italy, Spain and the United Kingdom are 
among the highest in Europe. In February, the prices in Spain were the lowest in Europe.
European market prices 
€/MWh
350
300
250
200
150
100
50
0
  OMIE             
 APX Netherlands             
 IPEX Italy (PUN)             
 EPEX Germany            
 NordPool           
 EPEX France               
 N2EX United Kingdom
INTRADAY MARKET 
Energy trading in the intraday market auctions stood at 31 TWh (includes all transactions in 
which at least one Spanish agent participated), which represents 17.6% of what was traded 
in the day-ahead market.
The arithmetic average price of the intraday market in 2021 stood at 112.58 €/MWh, a value 
that was 0.6% higher than the day-ahead market.
On the other hand, energy trading in the continuous intraday market stood at 6.5 TWh, compared 
to 5.2 TWh the previous year. The average weighted price in Spain stood at 113.73 €/MWh, 
fluctuating between 37.35 €/MWh in February and 234.84 €/MWh in December.
Energy sales in the  
intraday market auctions
31 TWh
+5.9 %
Compared 
to 2020
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
2020
2021

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ANCILLARY SERVICES
The energy needs managed through the ancillary services in 2021 were 5.8% higher than in 
the previous year. Energy scheduled for security reasons was 6.2% lower, as a result of the 
decrease in energy for technical constraints of the Daily Base Operating Schedule (PDBF), 
which stood at 19.4%, while the energy for real-time technical constraints doubled. Balancing 
energy increased by 21.4%, mainly as a result of the increase in secondary control power and 
the coming into force at the end of 2020 of the International Grid Control Cooperation  
(IGCC - imbalance netting process that avoids the need for secondary control power).
The volume of energy for technical constraints of the Daily Base Operating Schedule 
represented 38.9% of the total, a percentage that is lower than the value of 51% registered 
the previous year. 
Energy requirements covered through ancillary 
services
GWh
January-December 2021
January-December 2020
%2021/2020
Upward 
energy
Downward 
energy
 
Total
Upward 
energy
Downward 
energy
 
Total
Upward 
energy
Downward 
energy
 
Total
Energy scheduled for  
security reasons
9,475
912
10,386
10,159
914
11,074
-6.7
-0.3
-6.2
Technical constraints (PDBF)
7,789
253
8,042
9,431
548
9,979
-17.4
-53.8
-19.4
Real-time technical constraints
1,686
659
2,345
728
366
1,094
131.5
80.0
114.3
Balancing energy used
5,824
4,480
10,305
4,890
3,599
8,490
19.1
24.5
21.4
Replacement Reserve (RR)
2,168
852
3,020
2,107
872
2,979
2.9
-2.2
1.4
Secondary control
1,300
1,541
2,840
1,212
1,631
2,843
7.2
-5.5
-0.1
Tertiary control
2,160
1,322
3,482
1,543
1,061
2,603
40.0
24.7
33.7
IGCC (1)
197
765
962
28
36
64
599
2.023
1.398
Total energy managed
15,299
5,392
20,691
15,050
4,514
19,563
1.7
19.5
5.8
(1) Secondary control power avoided thru the use of the European platform for secondary control imbalance netting.

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5  Electricity Markets 
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Average weighted prices of ancillary services
GWh
Cost of ancillary services in m€
2020
2021
%21/20
Upward 
energy
Downward 
energy
Upward 
energy
Downward 
energy
Upward 
energy
Downward 
energy
Daily base operating schedule (PDBF)  
technical constraints
75.3
30.7
145.9
89.0
93.8
189.5
Real-time technical constraints
146.1
7.4
269.7
37.6
84.6
405.8
Secondary control
35.8
29.0
112.1
100.5
213.1
246.8
Tertiary control 
42.6
19.3
137.4
59.1
222.6
206.4
Replacement Reserves (1)
43.1
22.0
144.3
70.2
235.0
218.4
(1) Balancing energy from replacement reserves (RR) has a single price. The value represented in the table corresponds to the weighted 
average price according to the activated upward or downward balancing energy needed to cover the need of the Spanish Electricity 
System. Up to and including February 2020, the figures correspond to the weighted average price of the energy managed through the 
generation-consumption deviation management service.
2020
2021
Daily base operating schedule (PDBF) technical constraints
501
724
Real-time technical constraints
423
443
Technical constraints
78
281
Secondary control 
95
262
Deviation management
40
107
Other*
-19
-46
Power control factor
-17
-15
Total Ancillary services
601
1,032
∆2021/2020
71.7%
(*) Includes non-fulfilment of balancing energy, deviation balancing and deviations between systems.
In 2021, the cost of the ancillary services was  
1,032 million euros, 71.7% higher than in  
the previous year.

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Weight of the impact of the ancillary services on 
the final price
%
The impact of ancillary services on the average final price of energy was  
4.26 €/MWh, higher than the 2.54 €/MWh of 2020. This increase was due to the high 
prices registered in all markets. If we compare the impact of this service in the final 
average price, we can see that this year’s price was reduced (3.6% compared to 6.3% 
the previous year).
In April 2020, ancillary services accounted for 20% of the average final price of energy, 
when they are usually below 5%. The exceptional situation in the operation of the system 
due to COVID-19 led to a greater need for the use of ancillary services. In February 2021, 
the month with the highest percentage of renewables during the year, its weight is the 
highest this year.
  Ancillary Services (AS)           
  Average price of Ancillary Services
25
20
15
10
5
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
2020
2021

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The impact of ancillary services on the average final 
price of energy was 3.6%, a value that is lower than 
the impact of 6.3% registered in 2020.
Replacement Reserves Markets
The average hourly band of secondary regulation assigned to upward energy was 580 MW, 
compared to 593 MW the previous year, with an impact of 1.08 €/MWh on demand served, 
170% higher than the previous year. The annual weighted average price stood at  
24.5 €/MW, and the highest monthly price was registered in October with 41.45 €/MW).
Secondary control power and price  
MW and €/MW
650
45
600
40
550
35
500
30
450
25
400
20
350
15
300
10
250
5
200
0
  Average upward energy          
  Average downward energy          
  Price
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC

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Pumped storage  
consumption 
0.1 %
Hydro 
0.2 %
Coal 
20.2 %
The energy scheduled in phase I for resolving technical constraints of the Daily Base 
Operating Schedule corresponded mainly to combined cycle and coal-fired technologies. 
The downward energy in phase I was all but negligible.
Energy scheduled for security reasons
The energy scheduled to resolve technical constraints amounted to 10,386 MWh, 6.2% less 
than the previous year. Upward energy scheduled accounted for 91.2% of the total energy.
The energy scheduled to resolve technical constraints of the Daily Base Operating Schedule 
(PDBF) was 7,789 GWh of upward energy (17% less than the previous year) and 253 GWh of 
downward energy (half that of the previous year). The average value of the price of upward 
energy was 135.8 €/MWh, 80.4% higher than in 2020, and that of the price of downward 
energy was 82.8 €/MWh, nearly three times that of 2020. The impact on the average final 
price of energy was 1.83 €/MWh compared to 1.79 €/MWh the previous year. 
Monthly evolution of energy scheduled for security reasons 
GWh
Upward Energy in phase 1 
%
1,200
1,000
800
600
400
200
0
0
200
400
600
800
  Technical constraints of the PDBF           
  Real-time technical constraints
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
Combined cycle 
79.5 %

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The energy scheduled for technical constraints in real time totalled 2,345 GWh, slightly 
more than double the value of the previous year. 71.9% corresponds to allocations of upward 
energy and the remaining 28.1% to downward energy. The impact on the average final price 
was 1.16 €/MWh compared to 0.33 €/MWh the previous year.
Balancing markets
The balancing markets (secondary control, tertiary control, replacement reserve and secondary 
control power avoided through the use of the European platform for secondary control imbalance 
netting) had total energy requirements of 10,305 GWh. Of this total, 56.5% corresponded to 
upward energy managed and the remaining 43.5% to the downward energy managed.
The largest energy requirements were covered by tertiary and replacement reserve. 
Noteworthy is the significant share of renewable generation in these services.
Evolution of energy requirements covered through balancing energy
GWh
800
700
600
500
400
300
200
100
0
0
200
400
600
800
  Secondary control         
  Tertiary control          
  Replacement Reserves         
  IGCC
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
The energy scheduled for 
technical constraints in real 
time totalled 2,345 GWh, 
slightly more than double  
the value of the previous year.
Total energy requirements covered  
by the balancing markets
49.8 %
of the total energy required

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VOLUNTARY PRICE FOR SMALL CONSUMERS 
In the following graph, it can be seen how the voluntary price for small consumers (VPSC), 
known as PVPC in Spain, is conditioned by the day-ahead market. For this reason, the highest 
VPSC price was registered in December, while the lowest was registered in February.
The price of surplus energy from self-consumption is paid at a price very similar to the day-ahead 
market price.
Evolution of the VPSC, Day-ahead market and 
surplus energy from self-consumption
General tariff 2.0TD and 2.0A, prior to June
€/MWh
350,00
300,00
250,00
200,00
150,00
100,00
50,00
0,00
 Price of surplus energy from self-consumption           
  VPSC           
  Day-ahead market
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
On 1 June, the tariffs were modified, reducing their number and modifying the tolls and charges 
(which had remained unchanged since 2014). From that moment on, practically all domestic 
consumers are now covered by the 2.0 TD access tariff, which now includes hourly discrimination 
broken down into three periods each day for energy (peak, standard and off-peak) and two for 
the contracted power (peak and off-peak).
The new tolls and charges make the VPSC on weekdays much more expensive during peak 
hours. Thus, depending on the distribution of the percentage of consumption in the different 
periods, the cost of the access toll concept is affected and, therefore, this affects the total 
cost of the electricity bill.

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Cost in the electricity bill (in €)
€
200
150
100
50
0
  Initial           
  VAT reduced           
  Reductions
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
The high day-ahead market prices, which as has already seen have an impact on the 
regulated electricity bill, led to exceptional measures being taken to reduce the cost. Thus, 
in June, VAT was reduced (from 21% to 10%) if the contracted power does not exceed 
10 kW and if the wholesale market price exceeds 45 €/MWh. As of 16 September, charges 
were reduced by 96% and the electricity tax was reduced from 5.11% to 0.5%.
The graph shows how the one-off measures affected the cost of the electricity bill. With the 
first VAT reduction measure, a 9% reduction in the bill was achieved, while all the measures 
together reduced the bill by 23%.
In order to calculate the cost of the regulated tariff, if a comparison were made with the old 
2.0A tariff, considering a contracted power of 4.6 kW and a consumption of 3,900 kWh/year, 
with the consumption scenario published on the CNMC website, which is weighted as follows: 
45% off-peak hours, 26% standard hours and 29% peak hours. The cost of a typical electricity 
bill for 2021 as a whole would be €1,023, a value that is 43% higher than what would have been 
paid for the same consumption in 2020, i.e., almost €308 more per year. This would be the 
highest electricity bill ever (even though the calculation takes into account the tax reduction 
measures put in place by the Government).
Of the 1,023 euros that this typical customer would have paid for their electricity consumption 
in 2021, 561 euros would correspond to the purchase of energy in the market (55% of the bill), 
311 euros (30%) would correspond to the regulated part of tolls and system charges and the 
remaining €151 would correspond to taxes (15%). Thus, although the cost of energy purchased 
on the electricity market would have increased by 178.7% compared to 2020, the total bill 
would only have increased by 43%.
The high prices of electricity experienced during 2021 meant that the final cost of energy had 
an ever-increasing impact on the cost of the electricity bill.
23 %

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97
The Spanish Electricity System 2021
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European Landscape
Energy generation from renewable sources 
(excluding pumped storage hydroelectric 
generation) continues to grow for yet another year, 
and despite the circumstances associated with 
the pandemic, it represented 38.7% of the energy 
produced in the ENTSO-E countries as a whole. 
The purpose of this chapter is to 
establish a comparison between the 
European countries belonging to 
ENTSO-E in the different areas of 
the electricity system. Comparisons 
are based on information that is 
publicly available on the ENTSO-E 
Transparency Platform. The information 
used is governed by Regulation (EU) 
No 543/2013, which establishes the 
common and standardised criteria that 
must be followed by member states 
when submitting data. For this reason, 
certain discrepancies may arise with 
the rest of the chapters of this report 
for the specific case of Spain, where 
consolidated data at a national level  
is obtained using a power 
measurement system.

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In a context still marked by the pandemic, ENTSO-E countries as a whole, showed an increase 
of 3.9% in electricity demand in 2021 compared to the previous year, an increase that offsets 
the decrease of 3.6% in 2020 compared to 2019. The majority of ENTSO-E member states 
registered increases in their demand, while only the Netherlands, Bosnia-Herzegovina and 
Serbia recorded a decrease in demand. The most significant increases have occurred in some 
of the most relevant European countries such as Finland or Italy.
Increase in electrical energy demand in ENTSO-E 
member states 2021/2020
%
   ≤ 0 %          
   > 0 % to  ≤  3 %          
   > 3 %
Source: data obtained from the ENTSO-E Transparency Platform as at 26/1/2022. The data is governed by Regulation (EU) No 543/2013, 
and is obtained from real-time systems and therefore differs from the consolidated data used for the specific case of Spain at national 
level, which is obtained using a power measurement system.
(1) Data not available.
SPAIN
2.5 %
IRELAND
4.7 %
ICELAND(1)
-
FRANCE
4.8 %
SWITZERLAND
     1.8 %
GERMANY
4.0 %
LUXEMBOURG
8.2 %
AUSTRIA
2.7 %
HUNGARY
3.8 %
POLAND
5.7 %
THE CZECH REPUBLIC 3.7 %
THE SLOVAK REPUBLIC  5.5 %
REPUBLIC OF NORTH 
MACEDONIA(1)  
CYPRUS(1) -
BELGIUM
4.0 %
NETHERLANDS
-1.6 %
NORWAY
4.6 %
SWEDEN
4.9 %
FINLAND
8.1 %
ESTONIA  6.0 %
LATVIA 3.6 %
LITHUANIA 4.5 %
SLOVENIA
3.6 %
MONTENEGRO
3.2 %
ALBANIA(1)
-
CROATIA 7.2 %
BOSNIA
-8.3 %
GREECE 
4.7 %
BULGARIA
5.2 %
SERBIA
-11.1 %
ROMANIA
1.9 %
PORTUGAL
1.4 %
DENMARK
6.4 %
ITALY
5.9 %

99
6  European Landscape
The Spanish Electricity System 2021
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THE SHARE OF RENEWABLE ENERGY CONTINUES ITS 
GROWTH PATH
Energy generation from renewable sources (excluding pumped storage hydroelectric generation) 
continues to grow for yet another year, and despite the circumstances associated with the 
pandemic, it represented 38.7% of the energy produced in the ENTSO-E countries as a whole. The 
variation in renewable energy in 2021 stood at 0.4% compared to the previous year, with solar 
energy experiencing the greatest growth compared to other technologies with a variation of 10.4% 
compared to 2020. In 2021, Spain occupied the tenth position in terms of coverage with renewable 
energy, being the fifth country in terms of coverage with wind energy and second in terms of 
coverage with solar energy, both calculated as a percentage of total electricity production.
Origen of the total energy production in ENTSO-E 
member states
TWh and %
2020
2021
%21/20
Nuclear
673.4
716.3
6.4
Classic thermal
927.1
974.5
5.1
Pumped storage (Net Supply)
44.3
46.3
4.6
Hydro
490.6
488.0
-0.5
Wind
388.0
380.7
-1.9
Solar
122.2
134.9
10.4
Other renewables
90.6
92.4
2.0
Total
2,736.2
2,833.3
3.5
Source: data obtained from the ENTSO-E Transparency Platform as at 26/1/2022. The data is governed by Regulation (EU) No 543/2013, 
and is obtained from real-time systems and therefore differs from the consolidated data used for the specific case of Spain at a national 
level, which is obtained using a power measurement system.
  Nuclear       
  Classic thermal       
  Pumped storage (Net Supply)       
  Hydro       
  Wind       
  Solar       
 Other renewables
2,833.3
TWh
2021
25.3 %
3.3 %
4.8 %
13.4 %
34.4 %
1.6 %
17.2 %

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System Report
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100
The following map shows the contribution of renewable generation to total demand 
coverage in each of the countries, with the Nordic countries, for yet another year, being 
ranked in the first positions.
Renewable energy structure over total production in 
ENTSO-E member states 
%
  < 20 %         
  ≥ 20 % to < 40 %         
  ≥ 40 % to < 60 %          
  ≥ 60 %
Source: data obtained from the ENTSO-E Transparency Platform as at 26/1/2022. The data is governed by Regulation (EU) No 543/2013, 
and is obtained from real-time systems and therefore differs from the consolidated data used for the specific case of Spain at a national 
level, which is obtained using a power measurement system.
(1) Data not available.
SPAIN
49.4 %
IRELAND
43.2 %
ICELAND(1)
-
FRANCE
21.1 %
SWITZERLAND
37.9 %
GERMANY
42.6 %
LUXEMBOURG(1)
-
AUSTRIA
72.5 %
HUNGARY
13.9 %
POLAND
14.6 %
THE CZECH REPUBLIC 12.7 %
THE SLOVAK REPUBLIC  21.0 %
REPUBLIC OF NORTH 
 MACEDONIA(1) -
CYPRUS(1) -
BELGIUM
19.1 %
NETHERLANDS
13.3 %
NORWAY
94.8 %
SWEDEN
62.8 %
FINLAND
45.5 %
ESTONIA  27.5 %
LATVIA 58.6 %
LITHUANIA 50.2 %
SLOVENIA
33.6 %
MONTENEGRO
61.7 %
ALBANIA(1)
-
CROATIA 67.8 %
BOSNIA
36.4 %
GREECE 
32.8 %
BULGARIA
16.9 %
SERBIA
33.1 %
ROMANIA
44 %
PORTUGAL
59.1 %
DENMARK
68.6 %
ITALY
37.2 %

6  European Landscape
The Spanish Electricity System 2021
Go to table of contents
101
ENERGY EXCHANGES IN 2021 WERE MOSTLY AS AN EXPORTER
A country’s energy exchanges fluctuate every year, depending on factors such as exchange capacity, 
market coupling and the influence of energy prices. In 2021, the net balance of electricity exchanges 
among ENTSO-E countries and with their neighbouring countries (who are non-member states) was 
as an exporter with more than 8 TWh. The largest exporters include France, Sweden, Germany and 
Norway, with export balances of 43 TWh, 25 TWh, 20 TWh and 17 TWh, respectively. On the other 
hand, the largest importers were Italy and Finland, with 43 TWh and 18 TWh, respectively.
Balance of energy exchanges among ENTSO-E member 
states and with neighbouring non-member states
TWh
  > 0  to  < 5 TWh    
  ≥ 5  to  < 10 TWh    
  ≥ 10 TWh           
  < 0  to  > -5 TWh    
  ≤ -5  to  > -10 TWh    
  ≤ -10 TWh           
  Electrically isolated
Source: data obtained from the ENTSO-E Transparency Platform as at 26/1/2022. The data is governed by Regulation (EU) No 543/2013, 
and is obtained from real-time systems and therefore differs from the consolidated data used for the specific case of Spain at a national 
level, which is obtained using a power measurement system.
SPAIN
0.8 TWh
IRELAND
0.5 TWh
ICELAND
-
FRANCE
-42.8 TWh
SWITZERLAND
3.6 TWh
GERMANY
-19.5 TWh
LUXEMBOURG
3.9 TWh
AUSTRIA
8.3 TWh
HUNGARY
12.8 TWh
POLAND
1.0 TWh
THE CZECH REPUBLIC -11.2 TWh
THE SLOVAK REPUBLIC  0.7 TWh
REPUBLIC OF NORTH 
MACEDONIA 2.5 TWh
CYPRUS  -
BELGIUM
-7.6 TWh
NETHERLANDS
0.4 TWh
NORWAY
-17.1 TWh
SWEDEN
-25.2 TWh
FINLAND
17.5 TWh
ESTONIA  2.6 TWh
LATVIA 1.8 TWh
LITHUANIA 9.2 TWh
SLOVENIA
-0.3 TWh
MONTENEGRO
-0.5 TWh
ALBANIA
0.0 TWh
CROATIA
4.3 TWh
BOSNIA
-5 TWh
GREECE 
3.7 TWh
BULGARIA
-8.6 TWh
SERBIA
0.7 TWh
ROMANIA
2.1 TWh
PORTUGAL
4.8 TWh
DENMARK
5.0 TWh
ITALY
43.4 TWh

System
report
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7

The Spanish Electricity System 2021
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103
Regulatory Framework
In the European context, 2021 was marked by the further development of the European Green 
Deal. An important milestone was the publication of Regulation (EU) 2021/1119 of the 
European Parliament and of the Council of 30 June 2021 establishing the framework for 
achieving climate neutrality (known as the European Climate Law), which sets a greenhouse 
gas emission reduction target of 55% by 2030 (compared to 1990 levels) and climate 
neutrality by 2050. To meet this 55% reduction target, the European Commission presented 
the ‘Fit for 55’ package on 14 July 2021. This new package consists of a roadmap entitled 
‘Fit for 55: delivering the EU’s 2030 Climate Target on the way to climate neutrality’, published 
together with a package of legislative initiatives, which are still in the approval phase,  
among which the following are noteworthy:
	
— Proposal for a Directive revising the Renewable Energy Directive.  
Among the main novelties of this proposal, the European Commission proposes to 
increase the EU’s renewable energy target for 2030 to 40% compared to the current 
target of 32%.
	
— Proposal for a Directive revising the Energy Efficiency Directive. 
The proposal seeks to raise the level of ambition for energy efficiency for the EU: 
proposing energy efficiency targets of 39% and 36% for primary and final energy 
consumption, respectively. 
	
— Proposal for a Regulation establishing the Carbon Border Adjustment Mechanism. 
The proposed mechanism would work as follows: EU importers will be required to buy 
carbon certificates corresponding to the carbon price that would have been paid if the 
goods had been produced under the EU’s carbon pricing rules.
	
— Proposal for a Directive amending Directive 2003/96/EC restructuring the 
Community framework for the taxation of energy products and electricity. 
The main purpose of the proposal for a Directive is to meet the climate change and 
energy targets of the EU and is based on the need to adapt the taxation of energy 
products and electricity contained in Directive 2003/96/EC to current EU policies.

104
System
report
www.ree.es/en
Beyond the ‘Fit for 55’ package, but within the European Green Pact, the agreement 
reached on 22 December 2021 between the European Parliament and the Council on the 
proposed revision of Regulation 347/2013 on guidelines for trans-European energy 
infrastructures was very important. Key elements of the political agreement include the 
introduction of mandatory sustainability criteria for all projects, the need to simplify and 
speed up the permitting and authorisation procedures, creating a reinforced framework 
for non-binding cooperation in the field of offshore grid planning, and strengthening the 
governance process.
Lastly, on 10 December, Commission Delegated Regulation 2021/2139 of 4 June 2021 was 
published, setting out the technical screening criteria for determining the conditions 
under which an economic activity qualifies as contributing substantially to climate 
change mitigation or climate change adaptation.
Regarding the national regulatory framework, one of the main regulatory milestones in the 
first half of 2021 was the publication on 21 May 2021 of Law 7/2021 on Climate Change 
and Energy Transition. This Law, which applies to various sectors, sets minimum energy and 
climate targets for Spain for 2030, in alignment with Spain’s 2021-2030 National Energy and 
Climate Plan (NECP). Additionally, in line with the provisions of the European Climate Law, a 
net-zero emissions target has been set for 2050.
As of June 2021, the new regime applicable to access tolls and fees came into force. 
This was established in Royal Decree 148/2021, published on 9 March, which sets out the 
methodology for calculating the fees related to the electricity system, and in CNMC Circular 
3/2020, of 15 January, which establishes the method for calculating the access tolls for 
electricity transmission and distribution. These new regulations allow all consumers to have 
a toll price that is based on hourly discrimination in terms of power and energy consumption, 
increasing the price difference between peak and off-peak consumption periods.
An important milestone in 2021 as a continuation of 
the development of the European Green Pact was 
the publication of Regulation (EU) 2021/1119 of the 
European Parliament and of the Council of 30 June 
2021 establishing the framework for achieving 
climate neutrality.

105
7  Regulatory Framework
The Spanish Electricity System 2021
Go to table of contents
As of last summer, as a result of the escalation of prices in the electricity and gas sectors, 
the Government began to introduce a series of measures aimed at reducing the cost of the 
electricity bill and protecting consumers:
	
—
Royal Decree-Law 12/2021 of 24 June 
adopting urgent measures in the field of 
energy taxation and energy generation, 
along with the management of the 
regulatory levy and the water-use tariff. This 
Law introduces certain tax measures, such as 
the reduction of VAT, applied to the electricity 
bill, from 21% to 10% up until 31 December 
2021, or the suspension of the Tax on Electricity 
Production (IVPEE), which is applied in Spain.
	
—
In September, an even more relevant Royal 
Decree-Law was published due to the scope 
of the measures adopted; Royal Decree-
Law 17/2021, of 14 September, on urgent 
measures to mitigate the impact on 
the gas and electricity retail markets of 
the steep rise in natural gas prices. The 
proposed temporary measures include the 
reduction of the Special Tax on Electricity 
(IEE) from 5.1% to 0.5%, the introduction of a 
mechanism to reduce the excess remuneration 
caused by the high price of natural gas on 
international markets (subsequently clarified 
in Royal Decree-Law 23/2021) and a 96% 
reduction in electricity system fees.
	
—
A month later, Royal Decree-Law 23/2021 
of 26 October on urgent energy 
measures to protect consumers and 
introduce transparency in the wholesale 
and retail electricity and natural gas 
markets was published. In this decree, the 
government has introduced new measures 
aimed at mitigating the impact of the price 
of electricity and natural gas on consumers, 
especially the most vulnerable ones,  
as well as increasing transparency in  
these markets.
	
—
A few days before the end of the year, 
Royal Decree-Law 29/2021 of 21 
December was published, adopting 
urgent measures in the field of energy 
to promote electric mobility, self-
consumption and the deployment of 
renewable energies, which extends 
until 30 April 2022 the application of the 
reduced VAT rate of 10%, as well as the 
application of the reduced rate of 0.5% of 
the IEE. For its part, the IVPEE will remain 
suspended until 31 March 2022.
Lastly, it should be noted that 2021 saw the start of the new Remuneration Framework for 
Renewable Energy in Spain (REER), established at the end of 2020 through Royal Decree 
960/2020, of 3 November, which regulates the remuneration scheme for the generation of 
electricity from facilities that use renewable energy sources. 
Throughout 2021, two auctions were held under this new remuneration framework: the first in 
January and the second in October. With the holding of these two auctions, a total of 2,902 MW 
of photovoltaic energy and 3,256 MW of wind power were allocated, thus complying with the 
indicative calendar for allocating the new REER, which established a planned aggregate capacity 
of 2,500 MW from wind power technology and 2,800 MW from photovoltaic technology by 2021.
With the escalation of prices in the electricity and gas sectors, 
the government began to introduce a series of measures aimed at 
reducing the cost of the electricity bill and protecting consumers.

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