With a battery, you’ll use about 80% of it. The table below shows how much electricity different sizes of solar panel systems can produce for different types of homes. You can also read more about 5 kW solar panel systems and see if they suit your home.
Solar panels are usually around 2m², which means the typical 430-watt model will produce 372kWh across a year. A solar panel system will need space on either side, so finding out your roof's area is only one part of working out how much solar electricity you can generate, but it's a great first step.
This means the whole solar panel system can generate 7.2 kWh of electricity in a day. This is calculated by multiplying the number of panels by the output per panel: 10 x 0.72 = 7.2kWh. The output per m² of an average 350W solar panel in the UK is about 132.5kWh.
If you know that your home uses less energy per year, you may find a smaller solar panel system more suitable. For example, a 2kW solar system is great for small homes with 1 – 2 bedrooms with energy use of up to 1,700kWh. If it's more energy you need, however, a 5kW solar system will generate around 4,250kWh.
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.
Solar panels are capable of powering all of your home appliances and, on super sunny days, even more! A 4kW system is likely to generate around 9.3kWh of energy each day, or approximately 3,400kWh per year. Typically a home with 2 – 3 bedrooms will use 2,700kWh each year, so a 4kW system is the most suitable size to choose.