Estimate your commercial solar savings
Four short steps. You'll get an indicative view of system size, annual benefit and financed cashflow — then a Solar Britain specialist can take it forward.
- 1Site details
- 2Energy usage
- 3Roof details
- 4Finance interest
This calculator provides an initial estimate only. A full proposal requires site-specific checks including roof suitability, electricity usage, planning considerations, grid connection, export permissions and finance eligibility.
Solar panel cost & savings — common questions
How UK commercial solar savings are calculated, typical costs and what to expect from the figures above.
How do you calculate solar panel savings?
Annual solar savings = annual generation (kWh) × the share you use on site × your electricity rate (p/kWh), plus any surplus exported to the grid at the export tariff. This calculator runs that maths using your roof area, postcode, electricity rate and usage profile.
How much will solar panels save me per year in the UK?
Indicative savings range from roughly £8,000–£15,000/yr for a small commercial roof (around 50 kWp) up to £150,000+/yr for large industrial roofs (500 kWp+). The bigger the daytime self-consumption, the better the return.
How much do commercial solar panels cost in the UK?
Typically £700–£1,000 per kWp installed in 2024–25. A 100 kWp system usually lands in the £70k–£100k range. Final pricing depends on roof type, electrical works, access and inverter choice.
How accurate is this solar savings calculator?
It's indicative only — designed to show whether your site is worth investigating. A full proposal involves a site survey, structural and electrical checks, half-hourly usage data, DNO/G99 review and a tailored finance model.
How much do solar panels save per month?
Roughly your annual saving ÷ 12, weighted toward summer months when generation peaks. Most UK commercial sites generate around 60% of annual output between April and September.
What information do I need to use the calculator?
Just your postcode, approximate roof area in square metres, and ideally your electricity rate (p/kWh) or monthly bill. Annual kWh usage gives the most accurate estimate but is optional.