Renewable energy – technology choices matter for air quality
A new briefing by the European Environment Agency (EEA) describes the use of renewable energy in the EU since 2005 and its contribution to the EU’s climate and energy goals. It also analyses the impacts of renewables growth on air pollutant emissions. The briefing is based on a detailed analysis by the European Topic Centre on Climate change Mitigation and Energy, which is published in their report “Renewable energy in Europe – 2019”.
According to EEA estimates, the share of energy from renewable sources was 18 per cent of gross final EU energy use in 2018, which is twice as high as in 2005. However, this share varies widely among EU countries, ranging from over 30 per cent of gross final energy consumption in Austria, Denmark, Finland, Latvia and Sweden to 10 per cent or less in Belgium, Cyprus, Luxembourg, Malta, and the Netherlands.
In 2018, across the EU, half of all renewable energy sources were used for heating (49%), followed by electricity generation (43%), and a much smaller proportion was used in transport (8%).
About one fifth of all heating consumption in the EU in 2018 originated from renewable energy sources. Biomass supplied about 80 per cent of all renewable heating, mainly as solid biomass burning. But the trend since 2005 is that biogas, heat pumps and solar thermal applications are developing faster than solid biomass burning, albeit starting from a much smaller base.
Of all the electricity consumed in the EU in 2018, more than 30 per cent originated from renewable energy sources. The growth in renewable electricity since 2005 has been driven by increases in onshore and offshore wind power and solar photovoltaic (PV) electricity, as well as by other renewable energy sources, e.g. solid biomass combustion.
In transport, renewable energy made up 8 per cent of all energy used in 2018, and various biofuels accounted for the bulk of this.
Compared with a scenario in which renewable energy would have stayed at the 2005 level, the fossil fuel savings due to the additional use of renewable energy after 2005 helped the EU achieve an estimated reduction in CO₂ emissions of 543 Mt (11%) in 2018. (Note that a zero GHG emission factor was applied to all energy uses of biomass.)
Germany, Italy and the United Kingdom were the countries with the largest absolute reductions in domestic fossil fuel use and GHG emissions between 2005 and 2018. However, national fossil fuel use and GHG emissions were reduced most effectively in Denmark, Finland and Sweden, where the renewable energy share increased fastest during this period.
Renewable energy sources help to improve air quality and human health, for instance by supplying electricity or heat without combustion. Consequently, technologies such as wind power, solar PV electricity, geothermal energy, heat pumps or solar thermal energy are most effective at cutting air pollutant emissions.
When biomass burning replaces fossil fuel combustion, however, the outcomes are mixed. Trade-offs occur particularly when solid biomass is burned in house holds for residential heating. Industrial emissions from combustion processes are more strictly regulated under EU legislation and have lower air pollutant intensities.
Overall, the additional use of renewable energy sources across the EU since 2005 led to a decrease in all SO₂ emissions of 156 kilotonnes (7%) in 2017, and a similar decrease in NOx, of 46 kt (1%). In contrast, the increased burning of biomass since 2005 actually raised EU-wide emissions of PM₂.₅ by 145 kt (11%), PM₁₀ by 149 kt (7%) and VOCs by 296 kt (4%).
The EEA points out that “to maximise the climate and health benefits of the energy transition, policy makers ought to assess carefully the interplay between renewable energy sources and with the wider energy mix, and pay attention to potential impacts from biomass burning”.
EEA Briefing published 19 December 2019: https:// www.eea.europa.eu/themes/energy/renewable-energy/renewable-energy-in-europe-key