Solar panel electricity systems capture the sun's energy using photovoltaic (PV) cells which are made from layers of semi-conducting material, usually silicon, and convert the sunlight into electricity. The stronger the sunshine, the more electricity is produced, but the cells can still generate some electricity on a cloudy day.
PV cells come in a variety of shapes and sizes. Most systems are made up of panels that fit on top of an existing roof, or you can fit solar tiles which are designed to be used in place of ordinary roof tiles, although these are not normally as cost-effective as panel systems.
As of October 2019 there were around a million PV installations in the UK, ranging from small domestic systems to the large solar farms which supply around half of all UK solar power.
Costs and benefits
With the rising costs of electricity, installing a solar PV system on the roof of your property could bring significant financial benefits.
As the power of the sun is free, once you have paid for the installation of your system, the electricity it generates is free, although you will still need to pay for any additional electricity you use from the grid. Some installation companies will also offer additional servicing packages to ensure your system keeps running safely and efficiently.
The cost of solar panels has plummeted in the last ten years due to advancements in technology but the cost of the solar panel system you need for your property will depend on its size and power needs.
According to the Energy Saving Trust, the average domestic solar PV system with a capacity of 3.68kW costs around £6,200 to install and can generate between 3,400 – 4,200 kilowatt hours of electricity a year – enough to power an average home.
The most popular systems for businesses have a 5 – 9kW output for small offices costing around £8,000 but a larger commercial operation such as a factory may require a system with an output of 25kW – 200kW and cost significantly more.
Solar power does not release any harmful CO2 into the atmosphere, so a small domestic PV system could help you reduce your carbon footprint by around 1.3 to 1.6 tonnes of CO2 per year, the same as the emissions produced from an average passenger car driving 4,000 miles.