CO2 intensity of heat and electricity generation

Indicator Assessment
Prod-ID: IND-213-en
Also known as: ENER 002
expired Created 22 Sep 2011 Published 07 Oct 2011 Last modified 25 Aug 2017
12 min read
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This content has been archived on 25 Aug 2017, reason: A new version has been published
Renewable energy contributed significantly to reduction in CO 2 intensity of the energy sector. In 2008, renewables contributed 10% in final energy consumption (see ENER28). Adding biomass to the traditional fossil fuel mix reduced the amount of CO 2 (electricity-only) emitted per KWh electricity produced by 8% in 2008. Combining fossil fuels, nuclear and renewables led to a reduction of 44% in CO 2 (electricity-only) emissions per KWh electricity produced in 2008. Between 1992 and 2007 g CO 2 emission per kWh of electricity and heat output decreased by 17% within the EU27 compared to the USA and China, where g CO 2 emissions per kWh decreased by 6% and 5% respectively.  However, looking at the global trend CO 2 emissions per kWh have increased by 8%.

Key messages

Renewable energy contributed significantly to reduction in CO2 intensity of the energy sector. In 2008, renewables contributed 10% in final energy consumption (see ENER28). Adding biomass to the traditional fossil fuel mix reduced the amount of CO2 (electricity-only) emitted per KWh electricity produced by 8% in 2008. Combining fossil fuels, nuclear and renewables led to a reduction of 44% in CO2 (electricity-only) emissions per KWh electricity produced in 2008.

Between 1992 and 2007 g CO2 emission per kWh of electricity and heat output decreased by 17% within the EU27 compared to the USA and China, where g CO2 emissions per kWh decreased by 6% and 5% respectively.  However, looking at the global trend CO2 emissions per kWh have increased by 8%.

How fast are we shifting towards a less carbon intensive electricity system in Europe?

CO2 Emissions per kWh of Electricity and Heat Output

Note: The figure shows the CO2 emissions per kWh of Electricity and Heat Output for the EU-27 level compared to the world, United States, the Russian Federation and China

Data source:


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CO2 (g) per KWh in 2009 (electricity only)

Note: The figure shows the CO2 generated electricity per kilo-Watt hour in 2009 per member country

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Reduction in CO2 public electricity (g) per kWh 2000 to 2008

Note: The figure shows the CO2 public electricity reduction per kilo Watt hour from 2000 to 2008

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Estimated CO2 emission factors for public electricity production in EU-27, 2008

Note: The figure shows the estimated CO2 emission factor for public electricity production in EU-27

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Over the period 1990 to 2008 total electricity production increased by 35% whereas CO2 emissions from public electricity plant decreased by 4.3% in EEA 32 Member States. The electricity production from fossil fuel increased by 38%. Nuclear and renewables energy increased by 18% and 54% over the same period (see ENER27).

In 2008, a combination of high coal and carbon prices accompanied by a drop in natural gas prices in induced heat and electricity producers to replace more polluting coal by gas and as a result, reduce their GHG emissions. The use of biomass and other renewable sources (wind and hydroelectric power) has also increased significantly in 2008. The economic recession, which started in December 2007 also contributed to emission reductions from several sectors including the manufacturing and construction, and road transport sectors. Road transport emissions were also affected by high oil prices, the continued decline in gasoline consumption and a reversal of the upward trend in diesel sales.

Figure 2 shows the CO2 intensity of electricity production in the EEA32 countries. Iceland and Norway have the lowest CO2 emissions (in g) per KWh produced due the very high share of geothermal and hydro electric and wind power used respectively.  Estonia and Malta have a very CO2 intense electricity production sector due to the high share of fossil fuels in electricity production.

In January 2008, the European Commission proposed a new directive that mandates a 20% share of renewable energies in the EU's energy mix by 2020.  By the 30th June 2010 EU states have to present their National Renewable Energy Action Plans showing how they will meet their 2020 target sourcing 20% of energy from renewable sources.

What is the contribution of various non-fossil generation capacities to the decarbonisation of the electricity system in Europe?

Under the IPCC guidelines CO2 emissions from combustion of biomass fuels are not included in totals for the energy sector if the biomass is sustainably produced because it is assumed that the CO2 would have been released anyway from natural processes. If biomass is harvested at an unsustainable rate (e.g. faster than annual re-growth) the emissions will have to be reported in MS Inventories under Energy, creating an incentive for MS to firstly use biomass to reduce CO2 emissions and secondly use sustainably produced biomass. Figure 3 clearly indicates that the penetration of biomass into the fuel mix reduces overall CO2 emissions from electricity production.

The switch towards less polluting fuels was driven by a combination of factors including market liberalisation, an extended gas infrastructure and environmental legislation. The liberalization of the EU energy sector enables the consumer to choose more freely between suppliers increasing the competitiveness amongst energy providers. The EU has made even further proposals to separate the production and distribution of large energy firms to further dilute the monopoly status of large ERYU energy providers.

Figure 4 clearly indicates that an update of biomass within the fuel mix reduces the CO2 emissions/kWh by 8%. CO2 emissions reduce even further by 44% per kWh when mixing fossil fuels with nuclear and renewable to generate electricity.

Electricity produced in the EU-27 from nuclear fuels continued to grow in absolute terms from the 1990s through to 2004 and has declined since then. Nevertheless, it grew at a slower rate than total electricity production. This meant that by 2008 its share of total production was 27.5%, down from 30% in 2005. More recently, environmental concerns and concerns over security of supply and high energy prices led to a new debate in Europe over the prospects of nuclear power. 
Another important contributor to electricity production came from renewable sources, whose share grew over the period to reach 17.6% in 2008, up from 14% in 2005. The drop in 2002 and 2003 was due primarily to low hydro production, from lower than average levels of rainfall. Coal and gas maintain a high share in electricity production of about 50%, with natural gas increasing at a fast pace. For more information see EEA2010 draft report (insert link once published).


How can the decarbonisation of the electricity system help the shift towards a more sustainable transport sector?

The decarbonisation of the electricity system will become more and more important with the increasing use of electric cars. Emissions from electricity consumption in the transport sector are currently not allocated to the transport sector but rather to the utilities according to UNFCCC GHG inventory guidelines. One of the climate mitigation options in the transport sector, the only sector in Europe where GHG emissions continue to increase at accelerated pace, is a switch to electric and hybrid cars. Therefore decarbonisation of the electric network, together with increase in energy efficiency and energy savings, is essential if we aim to achieve substantial GHG emissions reductions in the transport sector. The iTREN-2030 project showed that the contribution of electric cars to the EU27 car fleet will increase in the future[1]

Indicator specification and metadata

Indicator definition

Annual emissions of CO2 in UNFCCC reporting format (In Mt = million tonnes).

For CO2 only, the (national) totals do not include emissions from biomass burning or emissions or removals from land-use change and forestry (LUCF). The energy sector is responsible for energy-related emissions, such as those arising from fuel combustion activities and fugitive emissions from fuels. Fuel combustion activities include: energy industries, manufacturing industries and construction, transport, other sectors and other stationary or mobile emissions from fuel combustion. Fugitive emissions from fuels include: solid fuels and oil and natural gas.



Emission of pollutants:  Mt = Megatonnes

Policy context and targets

Context description

Emissions of CO2 from fossil combustion in electricity and heat production contribute significantly to total greenhouse gas emissions in the EU. The indicator estimates to what extent changes in efficiency, fuel mix and pollution abatement have influenced the CO2 intensity of electricity and heat production. These changes cannot directly be associated with the policies and measures introduced, but can provide an indication of their aggregate impact.

The trends evident in this factsheet, together with projections in other factsheets (e.g. see EN01), indicate that additional policy measures will need to be implemented in order to meet the EU’s longer-term emissions reduction targets, particularly for CO2. In addition to the EU’s commitments to reduce greenhouse gas emissions (of which CO2 is the main gas) under the Kyoto Protocol, In March 2007, the Council of the European Union decided that EU would make a firm independent commitment to achieving at least a 20 % reduction of greenhouse gas emissions by 2020 compared to 1990. It also endorsed an EU objective of a 30 % reduction in greenhouse gas emissions by 2020 compared to 1990 provided that other developed countries commit themselves to comparable emission reductions.

The total emissions of CO2 from electricity and heat production depend on both the amount of electricity and heat produced as well as the CO2 intensity per unit produced (which are also fuel specific). Therefore the policies and measures to reduce emissions need to address both demand (e.g. through improvements in the energy efficiency of buildings and appliances) to stem the rapid increase in electricity and heat production, as well as CO2 intensity per unit of electricity and heat produced (e.g. by fuel switching, generation efficiency).

A number of EU policies have contributed to efforts to curb total electricity and heat produced and CO2 intensity per unit produced. For example, the Directives establishing rules for the common market for electricity (2003/54/EC) and gas (2003/55/EC) have encouraged switching to cheaper and more efficient technologies, in particular to gas. The market liberalisation and competition resulting from these Directives also contributed to cheaper energy prices in the 1990s which may have encouraged energy consumption. However the steep increases in energy prices since 2000 and particularly after 2004, may help to constrain energy demand.

Another important policy is the integrated pollution prevention and control (IPPC) Directive (96/61/EC) which requires plants of less than 20MW to meet a set of basic energy efficiency provisions. For larger plants energy efficiency is covered by the plants’ participation within the EU greenhouse gas emissions trading scheme established by Directive 2003/87/EC. Under the Directive, each Member State was required to draw up a National Allocation Plan that included caps on CO2 emissions from all thermal electricity generating plant greater than 20 MW. A shift to less carbon intensive fuels for electricity generation, such as gas, and improvements in efficiency are important options to help generators meet their requirements under the directive.

The EC’s Green Paper on Energy Efficiency (COM(2005)265 final) highlighted opportunities to improve the efficiency of electricity and heat production by ensuring that: the most efficient CCGT technology is used; research is expanded to improve the efficiency of coal generation; the use of distributed generation is expanded particularly to make greater use of waste heat, and that in combination with this a greater use of combined heat and power (cogeneration) technology is realised. The Green Paper identified that 20% of EU energy use could be saved. The EC’s recent Action Plan for Energy Efficiency (COM(2006) 545 final) moved towards realising these savings and includes initiatives to make energy appliances, buildings, transport and energy generation more efficient, and introduces stringent new energy efficiency standards and financing mechanisms to support more energy efficient products. The EC also proposes to create a Covenant of Mayors of the 20 to 30 most pioneering cities in Europe and an international agreement on energy efficiency.


No targets have been specified

Related policy documents


Methodology for indicator calculation

CO2 emissions data are annual official data submissions to the United Nations Framework Convention on Climate Change (UNFCCC) and EU Monitoring mechanism. Combination of emission estimates based on volume of activities and emission factors. Recommended methodologies for emission data collection are compiled in the Intergovernmental Panel on Climate Change (IPCC). Guidelines for National Greenhouse Gas Inventories (IPCC, 2006). supplemented by the Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories (IPCC, 2000) and UNFCCC Guidelines (UNFCCC, 2000). Energy data collected annually by Eurostat.

Eurostat definitions for energy statistics

Eurostat metadata for energy statistics

Methodology for gap filling

Where data is not available for EU Member States, the data gap filling procedure has been used as agreed under the Monitoring Mechanism (EEA. 2007a).

Methodology references

No methodology references available.


Methodology uncertainty

Energy data have been traditionally compiled by Eurostat through the annual Joint Questionnaires, shared by Eurostat and the International Energy Agency, following a well-established and harmonised methodology. Methodological information on the annual Joint Questionnaires and data compilation can be found in Eurostat's web page for metadata on energy statistics:

Emissions: Officially reported data following agreed procedures. E.g. CO2 data are based upon annual submissions under the UNFCCC.

Data sets uncertainty

For energy related greenhouse gas emissions the results suggest uncertainties between ± 1 % (stationary combustion) and ± 11 % (fugitive emissions). For public electricity and heat production specifically, which is the focus of the indicator, the uncertainty is estimated to be ± 3 %. For the new Member States and some other EEA countries, uncertainties are assumed to be higher than for the EU-15 Member States because of data gaps.

Rationale uncertainty

No uncertainty has been specified

Data sources

Generic metadata


information.png Tags:
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DPSIR: State
Typology: Efficiency indicator (Type C - Are we improving?)
Indicator codes
  • ENER 002
Temporal coverage:

Contacts and ownership

EEA Contact Info

Cinzia Pastorello

EEA Management Plan

2010 2.8.1 (note: EEA internal system)


Filed under: , ,
European Environment Agency (EEA)
Kongens Nytorv 6
1050 Copenhagen K
Phone: +45 3336 7100