The Green House at Wicken, Ely, Cambridgeshire
This house was finished in 1999 / 2000 and since then it has been a net exporter of electricity to the grid each year. It demonstrates the integration of renewable technologies with a design to achieve maximum benefit from orientation and sunlight.
Background
Our client wished to build a house outside Cambridge, in a rural location which was to include stabling and a paddock. The building was to be first and foremost a house, and secondly to be designed to minimize the requirements for energy use. The energy saving measures include:
- PV electricity generation
- Solar water heating
- Re-use of the heat gained from the conservatory
- Additional thickness of insulation.
Construction
The house is constructed with a highly insulated external shell. Thermal mass is increased by having heavyweight construction materials inside the insulation. The mass is provided by 150mm thickness dense blockwork inner leafs to the walls and precast concrete ground and first floors. High levels of internal thermal mass will act as a heat store when coupled with large south glazing apertures, and the south facing conservatory.
Systems
The 3.7kW PV electricity generation system has been designed to contribute its surplus electricity to the Grid with 24m² poly-crystalline silicon PV panels. The south west facing are incorporated in the outbuilding roofs.There is a 3.5m² solar water pre-heating system to minimise the energy demand for hot water.
With the conservatory there is an air de-stratification system to distribute solar warmed air to the North rooms of the house.
Ventilation is by the Passive stack system.
There is a grey water recycling system, which includes rainwater capture.
Space heating when required is by an oil fired condensing boiler with underfloor heating. The space heating is complete with sophisticated zone controls and an external weather compensator, to increase efficiency.
