A Conservative Government will cut Britain's greenhouse gas emissions with a £1 billion investment in a high-tech National Grid network with a "smart meter" in every home, David Cameron said.
In an interview with The Guardian, the Tory leader said that the new smart grid technology was capable of delivering a "genuinely low-carbon world".
The project will form the centrepiece of a Green Paper setting out the Tory vision of a low-carbon economy, which Mr Cameron will unveil in an Internet-based launch event today.
The proposed smart grid would allow energy companies to tell people when they can buy electricity at the cheapest rates, as well as allowing consumers to feed power from solar panels back into the network.
It is hoped that the changes would significantly reduce electricity use, cutting customers' bills and slashing Britain's contribution to the carbon dioxide emissions which are blamed for global warming.
Mr Cameron described the new technology - also expected to form part of incoming US President Barack Obama's massive infrastructure programme - as "the internet for electricity".
"It is the thing that brings our plans all together, that makes it all possible and will deliver a genuinely low-carbon world," said the Tory leader.
Mr Cameron said that the Tories have already had discussions with National Grid officials about the practicalities of installing the new technology and will be able to approve the investment as soon as they come to office.
Of the Green Paper, Mr Cameron said: "The document brings together all the low carbon economy things we have said about green cars, about metering, about waste, about biogas, about renewables. All that is brought together in one place because we believe that if you are going to deliver a low-carbon economy you have got to have a vision, you have actually got to have a plan."
Shadow energy and climate change secretary Greg Clark said energy firms should pay for home insulation improvements and recoup the costs - plus interest - through bills.
Households would not notice the repayments, tied to a property for 25 years, as the reduction in energy costs would outweigh them, he suggested.
"The energy companies should be required to offer proven energy-saving insulations immediately. You would pay it back over your bill over a very long period," he told BBC Radio 4's Today programme.
"But because the savings would be immediate you would never see a charge because you always save from day one.
"The energy companies should advance that and they should get it underwritten by the Government for a commercial fee - much like our national loans guarantee scheme."
He said the interest rate would be around 5% or 6% but a basic package of £1,700 of improvements would save £160 a year in energy costs.