The building has 300 to 350 mm of Rockwool insulation in walls, roof and floor. The overall heat loss of the 400 m2 building is only 15 kW.
An Eco Diplomat heat pump uses the lake as a heat source using two 200 m loops of plastic pipe carrying a water-anti-freeze mixture and achieving a COP of at least three.
Hot water from the heat pump is supplied direct to the manifolds of the underfloor heating system, which serves the entire building.
The heat pump also provides domestic hot water for the kitchen, toilets and classrooms. It is aided by roof-mounted solar panels to pre-heat hot water in winter and meet the entire load in summer.
Over the lifetime of the building, the Eco heat-pump system is expected to reduce fuel costs by £27 000 and carbon emissions by 225 t.
