Renewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are renewable (naturally replenished). In 2008 about 19% of global final energy consumption came from renewables.
Air Heat Source Pumps are relatively easy and inexpensive to install and are the most widely used heat pump type. They work by extracting heat from the outside ambient air, even when the temperature is as low as minus 15 degree centigrade and delivering it to where it is required. It uses very little energy, typically for every unit of electricity used, several units of heat are delivered. So relating the energy purchased to the energy delivered, heat pumps can be 300% to 400% efficient.
Ground Heat Source Pumps only require the electricity to power the pumps and will typically deliver three to four times as much thermal energy (heat) as is used in electrical energy to drive the system. It works by extracting heat from the ground. Beneath the surface the ground stays at a constant temperature and a ground heat source pump can be used all year round – even in the middle of winter.
Ground heat source pumps have been used in other parts of the world, including North America and Europe, for many years.