How Much Do Commercial Solar Panels Cost in the UK? (2026 Guide)
If you run a business with a large roof and rising energy bills, commercial solar is one of the most reliable ways to cut costs and carbon. But what does it actually cost, and how quickly does it pay for itself? Here's a straightforward guide from the One Energy Projects team.
Typical commercial solar costs in 2026
Most fully installed rooftop systems in the UK currently fall somewhere between £700 and £1,200 per kWp (excluding VAT). The bigger the system, the lower the cost per kW, because fixed costs like design, scaffolding and grid applications are spread across more panels.
As a rough guide:
30kWp (small office, shop or farm building): around £25,000 to £36,000
50kWp (larger unit or school): around £40,000 to £55,000
100kWp (warehouse or factory roof): around £75,000 to £100,000
250kWp and above: typically £700 to £850 per kWp
These are ballpark figures. Your actual price depends on your roof, your site and your energy use, which is why we always start with a site survey.
What affects the price?
Roof type and condition: metal, tiled and flat roofs need different mounting systems, and an older roof may need checks or repairs first.
Access and scaffolding: tall buildings or tricky sites add cost.
Grid connection: larger systems need approval from your District Network Operator (DNO), and some sites need upgrades.
Panels and inverters: higher-efficiency equipment costs more but produces more from the same roof space.
Battery storage: adds upfront cost but lets you use more of your own solar power.
How long does it take to pay back?
For a well-designed system, payback is typically between 4 and 8 years. The biggest factor is how much of the electricity you use on site. Businesses that operate during daylight hours, such as manufacturers, warehouses, farms and schools, usually see the fastest returns, because every unit they generate replaces electricity they would otherwise buy at full price.
Any surplus can be exported to the grid through a Smart Export Guarantee (SEG) tariff, but export rates are much lower than what you pay for electricity, so we design systems around your usage rather than simply filling the roof.
With panels lasting 25 years or more, most businesses enjoy many years of very low-cost electricity after the system has paid for itself.
Tax relief and VAT
Commercial solar is generally treated as plant and machinery, so businesses can often claim capital allowances. Many can use the Annual Investment Allowance to deduct the full cost from taxable profits in the first year. VAT-registered businesses can usually reclaim the VAT. Rules depend on your circumstances, so check with your accountant before you invest.
Can you get solar with no upfront cost?
Yes. With a fully funded Power Purchase Agreement (PPA), a funder pays for and owns the system, and you buy the electricity it generates at a fixed rate that is usually lower than your grid price. It's a good option if you want lower bills without using capital.
Get an accurate quote
The only way to get a reliable figure is a site assessment. Our team will look at your roof, your half-hourly energy data and your goals, then give you a clear quote with expected savings and payback.
Contact One Energy Projects today for a free, no-obligation feasibility study.