Nearly 30% told us that their solar panels provided between a quarter and a half of the total electricity they needed over a year. There's a huge seasonal variation in how much of your power solar panels can provide. Read our buying advice for solar panels to see how much of your power solar panels could generate in summer.
The newest monocrystalline solar panels can have an efficiency rating of more than 20%. Additionally, monocrystalline solar cells are the most space-efficient form of silicon solar cell. In fact, they take up the least space of any solar panel technology that is currently on the market.
Exactly how much a solar panel costs per kilowatt depends on the type of solar panel you are talking about. Monocrystalline solar panels are the most expensive, and their cost per kW is somewhere around £1,000 – £1,500 whereas polycrystalline solar panels cost about £900 per kW.
Whether they'll generate enough electricity for your home year-round will depend on: if your solar panel system works in a power cut. It may be more realistic to think about whether you can be self-sufficient for the brighter parts of the year, and then top up your energy use from the grid at other times.
Household solar panel systems are usually up to 4kWp in size. That stands for kilowatt 'peak' output – ie at its most efficient, the system will produce that many kilowatts per hour (kWh). A typical home might need 2,700kWh of electricity over a year – of course, not all these are needed during daylight hours.
Polycrystalline panels are also known as multi-crystalline panels. Similar to monocrystalline solar panels, polycrystalline solar panels are also made from silicon. However, instead of a pure single crystal, many silicon fragments are melded together using high temperature to form the wafers.