The UK is on track to exceed targets to slash emissions by a third by 2020 - and would have met the goal even without the recession, the Government said today.
The "carbon plan", detailing progress on and future plans for reducing greenhouse gases, suggests that even without the economy contracting, green policies would be delivering a 34% emissions cut by the end of the decade.
Speaking before he travels to South Africa for the latest UN climate talks, Climate Change Secretary Chris Huhne said the plan showed the UK was "walking the walk" on global warming, and tackling the issue was "achievable and affordable".
And after George Osborne's autumn statement included little on the low-carbon economy and used language seen in some quarters as "anti-green", Mr Huhne insisted the Chancellor backed efforts to tackle climate change.
"He is absolutely committed to dealing with the problem of climate change, precisely because he is convinced of the science. He is not in the position like Nigel Lawson who is clearly sceptical of the science," Mr Huhne said.
The Climate Change Secretary said Mr Osborne had brought in green policies including the green investment bank and a carbon floor price and had agreed the fourth carbon budget which will slash emissions by half by the mid 2020s.
Mr Huhne said that the UK was absolutely committed to meeting its targets to cut emissions and that such a move would present big business opportunities.
So far progress has been made on "easy wins" such as replacing millions of boilers with more efficient, condensing models, which save householders around £95 on their bills a year, and insulating lofts and cavity walls.
Over the coming decade, cost-effective measures will continue, including more loft and cavity wall insulation, more efficient boilers and power stations switching from coal to gas.
The Government predicts there will be no extra costs in this Parliament on making progress towards halving emissions by 2025.
But meeting the goal in the 2020s will require large scale deployment of technology such as electric vehicles and heat pumps to warm homes, renewables, nuclear power and measures to capture and store emissions from power stations.
The cost to the economy of meeting the fourth carbon budget range from a benefit of £1 billion to costing £20 billion over the lifetime of the measures implemented - many of which will be in place long after the 2020s.
High fossil fuel prices would see savings from meeting the legally-binding goal to cut emissions by 80% by 2050.
Mr Huhne said the move to a low carbon economy could leave the UK depending on imports of fossil fuels for just 7% of its energy by 2050, compared to 88% if it did nothing.
It would also open up opportunities and jobs in a "thriving" green technology sector.
He said: "The carbon plan sends out a strong signal just before I head off to the Durban global talks that the UK is walking the walk on climate change and shows other economies that with the right planning it is achievable and affordable."
And he said: "To the public and businesses at home, rightly worried about the cost of living and the state of the economy, the carbon plan shows that the gradual rebalancing of our economy away from carbon is achievable and, in the long run, highly desirable.
"Every bit of progress we make is one more step away from import dependency, away from price volatility and from the emissions that threaten our way of life."