Are solar panels worth it in 2026?
The honest answer to the question everyone asks. Real install costs, current SEG rates, and three UK roofs where solar genuinely doesn't pay back.
The short version: for a south or south-east facing roof in southern or central England, with average household electricity usage and no significant shading — yes, solar panels pay back in roughly 6 to 9 years and generate £15,000–£25,000 over their 25-year warranty. For north-facing roofs, heavily shaded roofs, or homes with very low electricity usage, the maths is much weaker.
What does solar actually cost in 2026?
A fully installed 4 kW system — the typical size for a 3-bedroom UK home, around 10–12 panels — costs roughly £6,000 to £8,000. That includes panels, inverter, mounting hardware, wiring, scaffolding, and labour from an MCS-certified installer.
Costs scale roughly proportionally with system size. A 3 kW system runs around £5,000–£6,500. A 6 kW system, suitable for larger homes or households with an EV, costs £8,500–£11,000.
One important point: 0% VAT applies to solar installations until 31 March 2027. That's roughly a 20% saving versus the standard rate. After that, unless extended, the standard 20% VAT returns — adding £1,200–£2,200 to a typical install.
Where the savings come from
Solar generates two streams of value:
- Bill savings — every kWh you generate and use yourself is a kWh you don't buy from your energy supplier. At Ofgem cap rates of around 24.5p/kWh, every self-consumed kWh saves you 24.5p.
- Smart Export Guarantee (SEG) income — every kWh you generate but don't use yourself is exported to the grid, and your supplier must pay you for it. Rates currently range from about 4p to 15p per kWh depending on the supplier.
This is where most calculator sites mislead people. They assume 60–70% self-consumption, when the real figure for a household without a battery is usually closer to 40%. Why? Because solar generates during the day when most households are at work, and most consumption happens in the evening when there's no sun.
The four variables that determine your payback
1. Roof orientation
South-facing is best. South-east and south-west are nearly as good (within 5%). East and west typically lose 15% versus south. North-facing roofs lose roughly a third — and at that level, payback periods stretch beyond 15 years, which is rarely worth it.
2. Region
The Cornwall coast generates roughly 30% more annual solar than central Scotland. Our calculator uses regional yield factors from PVGIS data: 1.10 for the south-west, 1.00 for the Midlands, 0.92 for north England, 0.85 for Scotland.
3. Your electricity usage
Higher usage means more self-consumption, which means more value from each kWh generated. A household using 4,500 kWh/year (perhaps with an EV) gets noticeably faster payback than one using 2,200 kWh.
4. Whether you add a battery
A battery raises self-consumption from ~40% to 70–80% by storing daytime generation for evening use. It costs £3,000–£5,500 installed and adds 4–6 years to total payback — but if you can pair it with a time-of-use tariff like Octopus Go, it pays back faster.
Three roofs where solar isn't worth it
We're a calculator, not a sales site. Here are the cases where the maths genuinely doesn't work:
The north-facing roof in Scotland
A 4 kW north-facing system in Glasgow generates roughly 1,700 kWh/year — under half what a south-facing system in Plymouth produces. With 40% self-consumption and standard SEG rates, year-one savings come in around £230. On a £6,800 install, that's a 25-year payback. Not worth it.
The very low-usage household
If you only use 1,800 kWh of electricity a year (older retired couple, gas heating, no EV), most of your generated solar exports at 4–7p — not the 24.5p you'd save by self-consumption. A 4 kW system on a south roof generates ~3,400 kWh, of which only ~1,400 is self-consumed. Year-one saving: ~£500. Payback: ~14 years. Marginal at best.
The "moving in 3 years" house
Solar adds value to a property — research suggests around £1,500–£2,500 of resale uplift on a typical home — but nowhere near recovering the install cost in the first 3–4 years. If you're planning to move soon, solar is a poor investment unless you specifically value the energy independence or are doing it for environmental reasons.
What about grants?
The Feed-in Tariff closed in 2019 — there's no national grant scheme for solar at full retail anymore. But:
- 0% VAT on installation applies to everyone until April 2027 (saves ~20%).
- ECO4 can fund free or heavily subsidised solar for low-income households with EPC D-G properties — closing 31 December 2026, so apply now if you might qualify.
- Warm Homes Local Grant (England) covers solar within wider energy upgrade packages for low-income households.
- Home Energy Scotland offers interest-free loans toward solar installations.
- Consumer Loan Scheme launches April 2027 with 0% interest loans for solar — useful for households who can't afford the upfront cost but don't qualify for grants.
Use our grants eligibility checker to see what applies to you.
So — should you do it?
Run the numbers for your specific roof. Generic calculators assume south-facing perfection; the reality is that orientation, shading, your usage pattern, and your local solar yield combine to give very different payback periods.
Use our solar ROI calculator to model your roof. It accounts for postcode-based regional yield, orientation, pitch, shading, current import rate, your local SEG rate, and battery configuration. Run my numbers →
And before signing anything: get at least three quotes from MCS-certified installers, verify their certification at mcscertified.com, and read our guide on how to read a solar quote (coming soon) before committing.
Updated 28 April 2026. Figures based on Ofgem Q2 2026 price cap data, PVGIS irradiance estimates, and current MCS installer pricing surveys. This article is general information, not financial or installation advice.