Is solar worth it in the UK?
Tom and Aisha (an illustrative couple, not real people) live in a semi in Derby. Their roof faces roughly south, the quotes keep coming through the door, and they're asking the question everyone asks: will panels actually pay for themselves?
How much sun does a UK roof get?
More than most people expect. The EU's PVGIS solar model puts a 4kWp system at about 4,090kWh a year in London and roughly 3,630kWh in Edinburgh. The north gets less, but not dramatically less, and a well-angled roof matters as much as the postcode.
What it costs, and why now
Installing panels on a home currently carries 0% VAT, under HMRC Notice 708/6. That relief runs until 31 March 2027, and the rate then goes up to 5%. You may need planning permission if you live in a listed building or a conservation area, and the Planning Portal sets out the rules. Most homes don't.
Getting paid for what you export
Under the Smart Export Guarantee, run through Ofgem, larger suppliers must pay you for power you send back to the grid. Rates vary a lot from one supplier to another. Suppliers may ask for MCS certification before they'll pay, so check before you choose an installer.
The battery question
A battery stores daytime power for the evening. It costs a lot, though. The Energy Saving Trust puts a 5kWh unit at about £4,600 with a life of 10 to 12 years, so for some homes the battery won't pay for itself before it needs replacing.
What about the car?
If you have an EV, you can charge it from the panels or run it on a cheap overnight tariff instead. Which works out better depends on what your supplier pays for exports compared with its off-peak rate, so it's worth running both.
An example from our calculator
Our calculator ran an example for a driveway house in Leeds. Solar alone cost £8,436, saved £596 in the first year, paid back in year 15 and came out about £3,065 ahead over 20 years. Adding a battery took the cost to £13,036. It didn't pay back within 20 years and ended about £2,636 down, and that includes one battery replacement in year 12. These are illustrations only, and your home will differ. You can run your own postcode in the SolarSums calculator.
So, is it worth it?
Maybe, and that's the honest answer. For many homes, panels on their own pay back, but it takes well over a decade, not a few years. A battery often doesn't. For Tom and Aisha, the sensible first step is to put their own roof into the numbers before they sign anything.
Sources: PVGIS (European Commission JRC); HMRC VAT Notice 708/6; Ofgem, Smart Export Guarantee; Planning Portal; Energy Saving Trust.
Illustration and general information only, not financial advice.