Free tool
What does solar electricity really cost?
Divide a kit’s price by everything it will make over its life and you get the real cost of its electricity. Here’s that figure for every compliant kit in stock today, against what you pay the grid.
- middle kit in stock, over 20 years
- 5.0p /kWh
- grid price cap, West Midlands
- 25.60 p/kWh
- compliant kits in stock compared
- 16
Solar electricity over 20 years
4.3p
per kWh made, against 25.6p from the grid
About 6.0× cheaper than grid electricity, if you use every kWh.
- Made in 20 years
- 22,522 kWh
- Used at home
- 9,815 kWh
- Pays for itself in
- 7.4 yrs
- Saved after 20 years
- £1,550
The kit pays for itself over 20 years as long as the grid rate stays above 9.8p per kWh.
£963.04 at iHelios Living1,181 kWh in year one from 1,260 Wp near Birmingham, after the 800 W output cap and shading, losing 0.5% a year. “You use” assumes medium daytime use; exported electricity is unpaid. The unit rate is held at today’s level.
Today’s prices
Cost per kWh of every compliant kit in stock
Cheapest in-stock price, divided by the output facing south at 30° near Birmingham, cheapest per kWh first. Prices .
Only kits listed as Compliant on the ENA register and in stock now. Output from PVGIS for Birmingham, after the 800 W output cap, losing 0.5% a year. “You use” assumes you’re home some of the day and aren’t paid for export. Grid rate: West Midlands price cap, 25.60p per kWh, 1 Oct to 31 Dec 2026.
How it works
Three numbers to compare
A kit’s price is paid up front; grid electricity is paid as you go. Dividing the price by lifetime output puts them on the same footing.
5.0p
Per kWh made
Price ÷ everything the kit makes in 20 years. The UKSOL Pro Max 1260W Hybrid Mount Kit is the lowest today at 4.3p. This is the figure if you could use every kWh.
8.6p
Per kWh you use
Price ÷ only the electricity you use as it’s made. Export is usually unpaid, so this is the fairer comparison with your bill.
25.6p
The grid
The West Midlands price-cap unit rate. Every kWh of solar you use is a kWh you don’t buy at this price.
Lifetime matters. The middle kit costs 9.7p per kWh over 10 years and 5.0p over 20. If you expect to move house, or the inverter fails out of warranty, the 10-year figure is the safer one.
Every compliant kit in stock today costs less per kWh you use than the 25.60p grid rate over 20 years. The calculator shows the yearly saving and payback for your own home.
Cost per kWh: questions
How much does electricity from plug-in solar cost per kWh?
Spread over 20 years, the compliant kits in stock today cost between 4.3p and 8.1p per kWh they make, with a middle figure of 5.0p, facing south at 30° near Birmingham. Grid electricity on the West Midlands price cap is 25.60p per kWh.
Why is the cost per kWh you use higher than the cost per kWh made?
Plug-in solar only saves money on electricity you use while it's being made. The rest goes to the grid, and a self-fitted kit usually isn't paid for export. If you're home some of the day you use about 44% of the output, so each kWh you actually use carries about twice the cost. That still works out at 8.6p for the middle kit over 20 years, against 25.60p from the grid.
How long does a plug-in solar kit last?
Panels usually come with a performance warranty of 25 years or more, and microinverters with 10 to 15 years. We show 10 and 20 years in the table. If the inverter fails after its warranty, a replacement adds to the cost, so the 10-year figure is the cautious one.
Does the cost per kWh include degradation?
Yes. We assume panel output falls by 0.5% a year, the same assumption as the rest of the site. Over 20 years that means the kit makes about 10% less in its last year than its first.
What does the levelised cost leave out?
Installation or electrician costs, a new socket, inverter replacement, and changes in the grid price. We also don’t discount future savings. If you’re paying for any electrical work, add it to the price in the tool.
Sources
Free tools
Plan the rest of your setup
- Price trackerPrice history, drops and lows for every product
- Price per wattKits, inverters and batteries ranked by value
- Bundle vs buildKit price vs its parts bought separately
- Battery paybackIs a battery worth adding to your kit?
- Export earningsWhat your spare solar is worth
- Tariff matcherWhich tariff gives the lowest bill with solar