Government subsidies designed to promote renewables have been blamed for pushing up energy costs. Current national targets had not proved the most cost effective option and ditching them would give governments more flexibility over how to meet main emission cutting goal, Barroso said.
The policy outline is not expected to be followed by formal legislative proposals until early next year, and would still require lengthy debate by EU governments and the European Parliament to become law.
(Read more: Energy leaders warn of blackouts across Europe)
The one firm legislative proposal included in Wednesday's announcement was a scheme to prop up Europe's faltering carbon emissions trading market, with the aim of removing carbon permits from circulation to support prices.
Under the proposal, the Commission would set aside up to 12 percent of carbon permits from 2021, as long as certain conditions are met. Among the conditions is that the number of allowances to be set aside must exceed 100 million.
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