How do solar panels work?
When the sun shines on a solar panel, solar energy is absorbed by individual PV cells in the panel. These cells are made from layers of semi-conducting material, most commonly silicon. The PV cells produce an electrical charge as they become energised by the sunlight. This electrical charge creates a direct current (DC) of electricity. The current passes through an inverter to turn it into alternating current (AC) electricity. This is the kind of current needed for household appliances. The cells don’t need direct sunlight to work and can even work on cloudy days. However, the stronger the sunshine, the more electricity generated Solar panel systems tend to be made up of between six and 12 panels, with each panel generating around 400 to 450W of energy in strong sunlight.
Can I put solar panels on a flat roof?
Yes, it’s okay to install panels on flat roofs. Solar panels work best when angled towards the sun, so panels on flat roofs are normally tilted up to help maximise energy production. It’s important that any solar panel system maintains the integrity of the roof covering to keep it watertight. For this reason, many systems are weighted down rather than fixed through the roof covering. If you have a system that’s weighted down, the roof needs to be strong enough to deal with the added weight. If the roof isn’t strong enough, use appropriate fixings to ensure rain can’t cause any damage. Sometimes it might be recommended to renew the roof covering so that you get the best possible roof integrity and solar panel performance. Even though it may add to the cost, the overall solution will be cheaper in the long run.
How much do solar panels cost to install?
The average domestic solar panel system is 3.5kWp and costs around £7,000.
The amount you pay is influenced by:
- the size of solar panel system
- any difficulty accessing your roof
- whether you choose solar panels or tiles
- whether you integrate the solar panels into the building
Some of the installation costs can be shared if you already have scaffolding up for roof repairs or if you’re building a new house.
The cost of ground-mounted solar panel systems is more difficult to predict, as there are more variables such as:
- the type of mounting frame
- how far away it is from your house
Costs can vary between installers and products, so we recommend getting quotes from at least three installers.
How much will I save with a solar panel system?
The amount you could save using a solar panel system depends on a few things:
- How much of the solar electricity you’re able to use yourself.
- Whether you sign up for export payments like the Smart Export Guarantee (SEG).
- Where in the UK you live, as areas further south get more direct sunlight.
How do I maintain a solar panel system?
How do I maintain a solar panel system?
Solar PV systems need little maintenance. Keep an eye on nearby trees and keep them well trimmed to minimise shading of the array where possible. In the UK, rain will clean your panels if they’re tilted at 15 degrees or more. Debris is more likely to build up if you have ground-mounted panels, or if you live in an area with more dust in the air. In these cases, you might need to have the panels cleaned occasionally. Your solar panel installer should leave written details of any maintenance checks that you should conduct to ensure everything is working properly. This should include details of the main inverter fault signals and key troubleshooting guidance. Ideally, your installer should demonstrate this to you once the system has been installed. Speak to your installer for exact maintenance requirements before you commit to installing a solar PV system.