Commercial solar calculator
Estimate the cost, generation, annual saving and payback of solar on your commercial property in seconds. Indicative 2026 figures — a full proposal models your actual half-hourly data.
Your inputs
Indicative estimate
- Installed cost (ex-VAT)
- £—
- Annual generation
- — kWh
- Annual saving
- £—
- Simple payback
- — yrs
- CO₂ saved / year
- — t
- 25-year net value
- £—
Indicative only, using 2026 UK benchmarks (£/kWp by scale, 950 kWh/kWp/yr, SEG export ~12p). Excludes tax relief, which shortens payback ~1–2 years. Not a quote.
Get a fixed-price proposal →How the calculator works
The estimate uses the same 2026 benchmarks we model from. Installed cost runs £700–£1,100 per kWp and falls with scale, so the calculator applies a sliding rate from about £1,050/kWp at 50 kWp down to roughly £720/kWp at 1 MWp. Generation is your system size × 950 kWh per kWp per year (central-UK yield). Saving is the part you use on site valued at your electricity price, plus exported surplus valued at a 12p Smart Export Guarantee rate — which is why self-consumption matters so much. Payback is simple cost ÷ annual saving, before the Annual Investment Allowance and the business-rates exemption shorten it further.
For a let building, who captures that saving depends on the lease — see the split incentive solved. For the full cost picture by system size read the commercial solar cost guide, and for the tax levers the funding and tax page. When you are ready, our installation team turns the estimate into a fixed-price proposal.