With the feed-in tariff due to start in April 2010 (after a short consultation period to October) the benefits of installing a solar photovoltaic (PV) system on our houses before the end of the 2009 are probably better than we will ever have again.

Simply put, if you have a PV installation before the grant pot runs out, you will benefit from the Low Carbon grant of £2,000 to £2,500 now, then reap the benefits of next year's feed-in rates.

Having a PV system under 4kWp installed on an existing dwelling will attract a feed-in payback of 36p a kWh of electricity you generate. Whether you use your PV power or export it to the national grid as surplus, you will still get paid 36p for each unit.

The Feed In Tariff is only the Government subsidy. Your electricity company will probably top that up by 5p to 41p a unit (rates vary depending on whether they just pay for the electricity you export, or all the units that you generate).

To give a basic example of a standard 2.14kWp PV installation, your annual 'earnings' will be: 1800 units X 41p = £738 every year. Your hidden benefits will be a third or more of your electricity use will be free.

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About the Author: Chris Rudge is a qualified electrician who specialises in renewable energy.

About the author: Chris Rudge is a qualified electrician who specialises in renewable energy.

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