The government needs to multiply investment in clean energy four-fold to avoid breaking laws on renewables and climate change, official advisers say.
This would raise the annual energy bill of a “typical household” by £100 by 2020, says the Committee on Climate Change (CCC).
But it says that is a cheaper option than a new “dash for gas”.
It says the potential advent of a shale gas boom in Europe is not a “game-changer” for energy policy in the UK.
The committee’s annual report to Parliament confirms that greenhouse gases fell in the UK by 7% in 2011, but says most of this was down to the warm winter, rising fuel costs and falling incomes.
Only 0.8% of the CO2 cut was due to policies from government.
“We have to move from good intentions and we need to do it very quickly,” said David Kennedy, chief executive of the CCC.