Image caption The government says its priority is to keep household energy bills as low as possible

Government energy policy changes since the election are likely to increase CO2 emissions, according to BBC analysis.

The government said subsidies had become over-generous and changes were needed to keep energy bills down.

But opposition parties say the changes overturn a decade of consensual energy policy and are furious they have not been subject to parliamentary debate.

The BBC's audit suggests some moves will save consumers money, but others will actually increase bills.

The chancellor's vehicle excise duty changes, for instance, will make motoring more expensive for the drivers of small clean cars.

And ministers' political decision to reject onshore wind energy and solar power in the countryside is likely to stem the growth of two of the UK's cheapest sources of clean energy.

These may need to be replaced by more expensive types of clean power if the UK is to meet its long-term climate change targets.

Affordability

Adrian Gault, chief economist for independent government advisory body the Committee on Climate Change, told BBC News that even changes designed to reduce bills might indirectly increase them in the long run.

He said the uncertainty generated by the U-turns in policy would increase the risk to lenders and so increase the cost of borrowing, which could push bills up.

Many analysts say the changes made since the election appear to be shifting the UK away from the broad energy policy consensus which sought to promote as many different energy sources as possible.

Previous policy sought to find a balance between keeping the lights on, bills low and emissions down - but the Financial Times newspaper reports a Department for Energy and Climate Change (DECC) contact saying affordability had now taken precedence over emissions.

Our energy policy audit asks whether policy changes are likely to increase carbon emissions and whether they are likely to raise or lower bills.

Planned Conservative policy changes since election Is this likely to cut or increase bills? Is this likely to increase CO2 emissions? Block solar in the countryside Increase Yes Cut industrial solar subsidy Cut Yes Cut solar subsidy on homes Cut Yes Cut biomass subsidy Cut Yes Cut biogas subsidy Cut Yes Scrap Green Deal Increase Yes Cut zero carbon homes Increase Yes Impose carbon tax on renewables Debatable Yes Block onshore wind Increase Yes Increase tax on small cars Increase Yes Tax breaks for oil and gas industry Neutral Yes Cut zero carbon offices Increase Yes Cut support for community energy Cut Yes Sell Green Investment Bank No impact Debatable Freeze fuel duty escalator Cut Yes Diesel generator subsidy increase Increase Yes

It is impossible to put detailed figures on the impact of all the policy changes, so our audit table is indicative, and some of its broad judgments are open to debate.

Prof Jim Watson, research director for the UK Energy Research Centre, called the audit table "a very useful exercise" and agreed that most of the policy changes were likely to increase CO2 emissions just as the prime minister is preparing for a UN summit at which more than 150 nations have promised to reduce emissions.

Dustin Benton, head of energy and resources at Green Alliance, said the audit was broadly right, while Adrian Gault said he also largely agreed with the analysis.

"It's very hard to quantify precisely the impact of individual policies," he said.

"Some will have a small impact on CO2 emissions, but others will have a bigger effect.

"Probably the bigger impact will come from the large amount of policy uncertainty which will lead to reduction in low carbon development. Industry is very, very unhappy about the uncertainty that's been created."

Image copyright PA Image caption Subsidies for solar energy are among those to have been cut

A spokesman for the DECC said: "We are fully committed to getting a global deal to tackle climate change in Paris.

"However, our priority at home is to keep bills as low as possible for hard-working families and businesses, while reducing our emissions in the most cost-effective way.

"Government support has driven down the cost of renewable energy significantly."

A government advisor did not comment on whether changes so far would put up emissions, but said the government was committed to carbon targets and would be introducing new UK energy policies before the climate summit in Paris.

'Shameful'

The government says that under the influence of the Liberal Democrats, subsidies - particularly to solar power - were lavish.

But Lib Dem peer and former coalition government minister Lynne Featherstone said: "Huskies will be turning in their graves.

"For five years we fought sceptical Tories to invest billions in renewables, set out ambitious climate change targets and create the Green Investment Bank.

"In six months since (the election) we have seen an unravelling of all these positive changes in favour of short-term financial gain. It is shameful."

Labour's Lisa Nandy, shadow energy and climate change secretary, said: "This reckless set of decisions by ministers to unravel energy policies designed to get new, cleaner power stations built is damaging our energy security at a time when we urgently need investment to keep the lights on.

"They also mean we will see higher levels of carbon pollution right at the time when Britain should be leading the way to achieve a strong climate agreement at the Paris Summit."

David Cameron pledged before the election to keeping to the Climate Change Act, which demands step-by-step reductions in C02 in five-year budgets.

The UK has been praised by the UN for its work on securing an international climate treaty, but the organisation's Environment Programme's chief scientist, Prof Jacquie McGlade, recently told BBC News she was alarmed by policy changes within the UK itself.

Follow Roger on Twitter @rharrabin