Heating houses by sunlight
How sustainable is the PV part of the Oxford solar house?
Think about the following:
- Just four hours of sunshine provide the building with enough electricity for the day.
- Any surplus electricity produced during daytime is sold to the National Grid. Dr Roaf sells about 500 kilowatt-hours of electricity per year.
- At night and in winter, when extra electricity is needed, this is imported into the house from the National Grid. This means that the house doesn't use a set of batteries, which would not be sustainable because of the polluting chemicals used in them.
- Power generated by the PV cells is used to power an electric car, as well as household appliances.
- Carbon dioxide emissions are very much lower than for comparable non-solar houses elsewhere (this is a result of all the different features of the house).
- The PV system takes the place of a normal roof, but costs £25,000 more than a tiled one.
How sustainable is solar power generally?