The government must resist a second "dash for gas" if it wants to tackle climate change and rising energy costs.
Greenhouse gas emissions fell by 7 per cent last year, but climate change measures led to a drop of just 0.8 per cent, with most of the reduction due to milder weather, higher energy prices and lower incomes, the Committee on Climate Change said.
Emissions should be falling by around 3 per cent a year if the UK is to meet legally binding targets to tackle climate change.
Much greater investment is needed in low carbon energy, including onshore and offshore wind, nuclear and technology which captures the carbon from gas and coal and stores it permanently underground, the committee said.
More progress is needed to insulate cavity and solid walls for homes and very few households are currently switching to renewable heating, while consumer response to electric vehicles remains "cautious".
As the committee published its fourth annual report to Government on progress made to tackle climate change, chief executive David Kennedy warned that the need for action was urgent.
Companies are currently putting in just a third of the annual investment needed for onshore and offshore wind, the pipeline for new nuclear power plants was "very weak" and the timeline for demonstrating carbon capture and storage had slipped.
Recent government announcements, including emissions performance rules that would allow gas power stations with unchecked emissions to operate until 2045 and measures to encourage some new gas plants to maintain secure electricity supplies, have raised the possibility of a new dash for gas to keep the lights on.
The first dash for gas in the 1990s drove down the UK's emissions as power generation switched from dirtier coal.
But the committee warned that relying on gas would be more expensive than investing in low carbon technology, such as nuclear power, due to gas costs and the rising "carbon price" electricity generators have to pay for their pollution.
It would also make it difficult to meet legally binding targets to cut carbon.
"There should not be a second dash for gas and the government should say that confidently," Kennedy said.
"There have been mixed messages coming from government about the role for gas, and they've got to provide the clarity that it's not a sensible thing to do for carbon and it's not a sensible thing to do for security of supply."