By Alex Kirby
BBC News Online environment correspondent
A mini-power station on the roof of many UK homes will soon be possible and affordable, a British think-tank says.
Integrated solar fascia and glass on a London building
The Green Alliance, an independent body which advises policy-makers, says that micropower schemes have come of age.
In a report which will be published on 15 September, it says the Sun, the wind and even the heat in the soil can all provide clean energy for a household.
The report says micropower can help the UK to keep its promises on tackling climate change, and also to save money.
Entitled A Micro-generation Manifesto, it describes the concept as "the generation of low-carbon heat and power by individuals, small businesses and communities to meet their own needs."
The report says: "Bringing energy generation closer to people in this way will forge the vital link between our concern about climate change and our energy consumption in the home...
Heat pumps have great potential
"Homes with micro-generation are also affordable homes, with low or zero energy costs.
"And by curbing the rising demand for imported electricity, home energy generation can avert the need for investment in large new power stations and the aging grid network."
Examples of micropower the report mentions include:
The Green Alliance says that with domestic energy demand increasing almost as fast as that of transport, the government should make micropower a priority.
ground source heat pumps: they extract stored solar energy from the ground to run a home's central heating, and can cost as little as an oil-fired boiler to install. Widely used in the rural US, they produce three or four units of heat for every unit of electricity they use, and can be reversed to provide cooling
systems using solar power to heat water
generating electricity from the Sun by using photovoltaic (PV) panels
micro-turbines to capture wind power: no larger than a TV aerial or satellite dish, they can supply domestic energy and feed back any surplus into the grid. They will be available within a year, and can cost under £1,000 ($1,800)
micro-hydro schemes, which use the force of river currents to drive a small turbine
combined systems (CHP), burning woodchips or gas, designed to provide a household with both heat and power.
Huge increase ahead
It says the 2.4 million new homes planned by 2016 under the Sustainable Communities Plan will increase carbon emissions by 4.2 million tonnes, neatly cancelling out the amount of domestic energy saving the government hopes to achieve by 2010.
A recent review recommended doubling the house-building programme to complete 4.5 million homes by 2016, which would see carbon emissions rising by 7.8 million tonnes.
Wind power - but not as we know it
Carbon dioxide is the main gas produced by human activities which scientists say is exacerbating natural climate change.
Jo Collins of the Alliance said: "Micro-CHP boilers, mini-wind turbines and PV arrays should become familiar household fixtures. Micro-generation must be taken more seriously.
Defraying the cost
"These new technologies cut greenhouse gas emissions, provide reliable energy supplies, and ensure that every home is adequately and affordably heated.
"Installing just six panels of solar PV on a typical new three-bedroom house would reduce that household's carbon emissions by over 20%."
The Alliance says the cost of micropower would be an investment to set against the government's current annual expenditure of £1.85bn ($3.3bn) on winter fuel payments for the elderly.
It also wants micropower to be a condition of private finance contracts in the government's plans to replace or refurbish every secondary school in the country.