Tory plans for energy efficiency grants for more than three million homes would be piloted by 14 English councils and London's mayor, David Cameron says.

The party leader told the BBC the green message had to sound less "miserable", in an effort not to "depress" people.

The Tories say the grants would be worth up to £6,500 per home, with the standard upgrade worth about £1,500.

Households would repay costs via energy bills over 25 years. Labour said the plan was "unfunded" and a "green con".

Discussing the Tory plans, a Labour spokesperson said: "This is a green con. At the same time as saying they will cut the deficit, the Tories are making yet more unfunded commitments with no idea how they would find the billions their proposals would cost."

clashes inside and outside climate summit

China, India and their allies in the Third World were in open revolt at the UN climate summit in Copenhagen today as police fired tear gas and made at least 200 arrests to head off a march on the conference venue by environmental activists.

Lars Rasmussen, the Danish Prime Minister, personally took charge of the negotiations for a global climate accord as the conference entered its final three days, but the scale of the task he faces in bringing agreement to the cacophony of plans, promises and special pleading was clear.

Mr Rasmussen immediately faced concerted interventions from the floor, led by China's Vice Foreign Minister, He Yafei, at a decision to publish two new negotiating texts designed to move the process up a gear.

The party leader told the BBC the green message had to sound less "miserable", in an effort not to "depress" people.

What a complete w**ker! Now they want to jazz-up climate change to get "down with the kids". Oh please. This reminds me of those times when Microsoft tries to be "cool", but ends up looking like your grandmother after discovering text speak.

What a complete w**ker! Now they want to jazz-up climate change to get "down with the kids". Oh please. This reminds me of those times when Microsoft tries to be "cool", but ends up looking like your grandmother after discovering text speak.

What a complete w**ker! Now they want to jazz-up climate change to get "down with the kids". Oh please. This reminds me of those times when Microsoft tries to be "cool", but ends up looking like your grandmother after discovering text speak.

He has a point. All we hear about the green message is how badly it will affect us:
• More taxes = Govt agenda
• Less freedom to travel = Govt control
• Power shortages = lack of investment
• Fuel prices rising = greedy barstewards

…and more. If you want people to actually take the agenda on board and willingly follow, you have to emphasise the positive. At the moment this is not happening.

It’s all doom, gloom and misery, which is just added to the doom, gloom and miser caused by all the other bad things that are going on at the moment.