A leaked European Commission consultation paper has said EU countries will have to increase their investment in renewable energy if they are to keep their climate pledges.
According to the paper, member states must increase the amount of electricity they produce from renewable sources from a quarter at present to a half by 2030.
Currently, 23 countries around the globe are using renewable generation to produce more than 10% of their total energy consumption.
The commission paper, which will be published next week, says: "Reaching the EU 2030 energy and climate objectives means the share of renewables is likely to reach 50% of installed electricity capacity.
"This means that changes to the electricity system in favour of decarbonisation will have to come even faster."

The paper suggests that immediate cross-border power trading should be introduced to meet demand without the need for storage.
Oliver Joy, a spokesman for the European Wind Energy Association, told The Guardian: "Even with a binding provision, we are seeing the Netherlands, UK and France potentially missing their 2020 target [to source a fifth of energy provision from renewables]."
For the first three months of this year Costa Rica has run entirely on renewable energy, helped by heavy rainfall powering its four hydroelectric plants.
Apple is to invest $1.7bn in data centres in Ireland and Denmark that are run entirely on renewable energy.
Image: Wind turbines along the shore of Bønnerup Strand, Denmark (Dirk Goldhahn/Wikimedia Commons)
