The building is heated by a system known as a heat pump.
A heat pump works by virtue of the fact that the temperature a metre or two underground is at a fairly constant temperature, while the air temperature varies considerably during the day.
Brockweir and Hewelsfield Village Shop and Cafe
The Heat Pump
Water leaves the heat pump at a low temperature and after circulating through the pipes below the field adjacent to the shop, arrives back at the heat pump about 5 degrees Celsius warmer.
As there is about 230 litres of water in the pipes this represents a considerable amount of energy.
Heat from this water is transferred to the heat pump. The heat pump raises the temperature to useable value.
The heat is now transferred to water, this being circulated in the heating pipes within the building.
A full explanation of the technology can be found at Wikipedia here
Since the shop opened, the average annual consumption has been 7236 kWh.
Compare this with an average house using economy 7 heating:
Low user 3,300 kWh
Medium user 6,600 kWh
High user 9,900 kWh
And the average house user, unlike the shop, is not opening the front door many times throughout the day.
Even during long cold spells, the ground source heat pump keeps the shop very warm. To do that using oil or electricity (there is no piped gas supply in brockweir) would be considerably more expensive.