Range of technologies

Air source heat pumps absorb heat from the outside air. This is usually used to heat radiators, underfloor heating systems, or warm air convectors and hot water in your home.

An air source heat pump can extract heat from the air even when the outside temperature is as low as minus 15° C.

Ground source heat pumps use pipes buried in the garden to extract heat from the ground. This is usually used to heat radiators or underfloor heating systems and hot water.

Beneath the surface, the ground stays at a fairly constant temperature, so a ground source heat pump can be used throughout the year - even in the middle of winter.

Hydroelectricity systems generate electricity from running water - usually a small stream.

Small or "micro" hydroelectricity systems can produce enough electricity for lighting and electrical appliances in an average home.

'Micro-CHP' stands for micro combined heat and power. It is a heating technology which generates heat and electricity simultaneously from the same energy source, such as oil or bio fuels.

While gas and oil are not renewable energy sources, the technology is still considered to be a ‘low carbon technology’ because it is more efficient than just burning the fossil fuel for heat and getting electricity from the national grid.

Solar electricity systems capture the sun's energy using photovoltaic (PV) cells. The cells convert the sunlight into electricity, which can be used to run household appliances and lighting.

PV cells don't need direct sunlight to work - you can still generate some electricity on a cloudy day.

Solar water heating systems use free heat from the sun to warm domestic hot water.

A conventional boiler or immersion heater is then used to make the water hotter (if necessary), or to provide hot water when solar energy is unavailable.

Wind turbines harness the power of the wind and use it to generate electricity.

Small systems known as "microwind" or "small-wind" turbines can produce electricity to help power the lights and electrical appliances in a typical home.

Wood fuelled heating systems generally burn wood pellets, chips or logs to power central heating and hot water boilers or to provide warmth in a single room.

Wood fuelled systems are considered a very low carbon option because the carbon dioxide emitted when wood fuel is burned is the same amount that was absorbed over the previous months and years as the plant was growing.