Heating houses by sunlight
The design of the solar house
Dr Roaf's solution was the Oxford solar house. Her design for the south-facing side of the house includes:
- photovoltaic cells on the roof, which capture energy from the sun and produce electricity. These meet about 77% of the household's electrical needs
- 5 square metres of solar panels, which collect energy to heat water
a glazed sun space, where air is heated by the sun to provide warmth to heat the house.
Other features of the house that help conserve energy and reduce carbon dioxide emissions include:
- triple-glazed windows
- low-wattage light bulbs
- energy-efficient domestic appliances
- extra insulation for walls, made from 150mm thick mineral wool batts
- a wood-burning stove to heat the ground floor (wood is a renewable energy resource)
- a conservatory and porch that let in natural light and keep out cold winds.
Gas-fired appliances are used for cooking and to heat water for the dishwasher and washing-machine in winter. Although gas is a fossil fuel, it produces far less emissions than oil or coal.