Solar energy is already used in a million UK homes for both solar electricity and thermal power. Last September, more power was generated by solar panels located on homes and in fields than by fossil fuels, which is a new record. Experts now predict that by 2020 10 million British homes will have solar panels.

There are two types of panel to consider: photovoltaic and solar thermal. The latter uses the sun's energy to heat water. The former uses solar PV cells that transform sunshine into electricity.

If you are tempted to invest, there are other considerations too. One of the main ones relates to sunlight access and whether your roof is shaded at all by neighbouring properties or trees.

An initial survey by a registered micogeneration specialist is the first step in establishing which system is right for you. The assessor will also confirm that your roof is of the right structural type and can support a solar system. For domestic properties, a mid-range 4kW system costs c. £6,000. It can be installed in as little as half a day.

The cost of solar power has dropped by 85pc since 2000. Now that costs are more attractive, researchers from the Imperial College London found that solar panels could be providing nearly a quarter of the world's needs by 2040 and almost a third just ten years later.

It's also worth noting that there is very little service and maintenance required with solar panels. However, dust build-up needs to be treated, as it can lessen energy production by a significant 7pc. This can be done with a hosepipe, so it's not a big job.

Solar PV panels also last for a good 25 years, so the investment is a solid one.