Grid-connected solar power

Generating your own household electricity

The cost of solar PV panels has fallen over the last few years, and solar photovoltaic arrays are now affordable for many households. Even better news is that you can now get government subsidies - the 'feed-in tariff' - for generating electricity with solar panels too. So as well as being environmentally friendly they are increasingly making good economic sense!

How a grid-connected solar PV system works

A grid connected solar system is really very simple. An array of solar panels is fixed somewhere where it receives good sunlight - usually on your roof, although ground-mounted panels in the garden may also be worth considering where you do not have a suitable roof.

Solar panels produce DC (direct current) electricity, which is ideal for charging batteries but will not power your household appliances. So a device called an inverter is then used to convert the DC electricity into 240 volts AC (alternating current). The inverter connects to the mains supply via a meter which monitors the total energy produced by the array.

Grid-connect inverters are quite sophisticated (and hence expensive) because they have a number of safety features, and have to ensure that the waveform generated matches precisely the waveform of the electricity of the national grid to which it is being connected.

Various solar panels can be used in grid-connected applications. The amorphous, flexible adhesive backed Unisolar panels are great for metal 'standing seam' roofs, though most installations use conventional framed panels, such as the Powerglaz Solar Panels. Solar tiles, glass laminates and large panels designed for building integration are also available.

Does it make sense financially?

To encourage the use of solar panels for generating domestic electricity, the UK government have brought in a 'Feed-in tariff' subsidy scheme, (they call it the 'Clean Energy Cash Back scheme'), that pays you for each kWh of electricity you generate (whether or not you use it in your own property, or feed it back into the national grid). You also get paid a smaller amount for the proportion that you do feed into the national grid.

This scheme makes domestic solar installations a genuinely attractive financial investment. However, to qualify for the scheme, your solar PV system has to meet strict standards and be installed by a certified installer. We work with certified installers to offer installations both locally in Cambridge (where we are based ourselves), and, through installation partners, through the rest of the UK.

Ultimately what matters to most homeowners is the payback time - how long they will have to wait until the system recoups its own cost. Under the new UK solar feed in tariffs, a payback time of 7-10 years may well be realistic. The calculation is a complicated one - you may be interested in our Grid-connect solar financial calculator to work out whether it makes sense for you.

Alternatively, it is possible to install a small system yourself using our range of carefully selected DIY grid-connect solar products. No wiring work is required, as the inverter simply plugs into a standard household socket. Although you won't qualify for the feed-in tarifs, you will still have free electricity when the sun shines and be doing your bit for the planet!

• Learn about solar feed in tariffs
• Learn about the Microgeneration Certification Scheme
• Find out about our installation service
• See an example of an installation
• Frequently Asked Questions
• Recommended installers