Solar and battery basics

Solar panels turn daylight into electricity that you can use in your home. A battery stores some of it for later. This guide explains the basics so you can tell whether it's worth looking into for your home.

We're not yet introducing solar and battery specialists. You can register your interest and we'll let you know when we are.

How solar panels work

Panels on your roof produce direct current (DC) electricity when light falls on them. An inverter converts it to the alternating current (AC) your home uses. Your home uses solar electricity first. Anything you don't use goes to a battery, if you have one, or out to the grid.

Panels still work on cloudy days, but produce much less. They produce most in summer and in the middle of the day.

Will it suit your roof?

• Direction. South-facing roofs produce the most. East and west-facing roofs still work well, spreading generation across the morning and evening. North-facing roofs are usually less suitable.
• Shade. Chimneys, trees and neighbouring buildings can reduce output significantly.
• Space and condition. Panels last 25 years or more, so the roof should be in good condition first.
• Your area. The North East gets less sun than the south of England, but solar can still work well here. An installer should give you an estimate for your specific roof.

What a battery adds

Most homes use more electricity in the evening, when panels produce little. A battery stores daytime surplus for the evening, so you buy less from the grid.

Some people also use a battery to store cheaper overnight electricity on a time-of-use tariff. Whether a battery is worth it depends on how much you use, when you use it and your tariff, so ask for figures based on your own usage.

Selling surplus electricity

Under the Smart Export Guarantee, larger energy suppliers must offer a payment for electricity you export to the grid. Rates vary widely between suppliers, so it's worth comparing. To qualify, the installation usually needs to be certified under the Microgeneration Certification Scheme (MCS), so check your installer is MCS certified.

Costs and VAT

At the time of writing, the installation of solar panels and batteries in homes in Great Britain is zero-rated for VAT until 31 March 2027. Check the current position on GOV.UK, as tax rules can change.

Permissions

Solar panels on a house are often allowed without planning permission, but there are conditions. Listed buildings, conservation areas and flats can be different. Your installer should also notify your local electricity network operator, as required.

Questions to ask

1. Are you MCS certified, and will I receive the MCS certificate?
2. How much electricity do you estimate my roof will produce, and how did you work it out?
3. Would a battery make a difference for my usage? Please show me the figures.
4. What do the panels, inverter, battery and workmanship guarantees cover, and for how long?
5. Does the price include scaffolding, the network operator notification and any upgrades to my electrics?