Solar savings calculator
Enter your electricity bill to estimate a sensible system size, the installed cost, annual saving and payback. Instant, indicative, and no details needed.
Indicative estimate
- Sensible system size
- 6 kWp
- Indicative installed cost
- £9,540
- Annual saving
- £1,055
- Simple payback
- 9.0 years
- CO₂ saved
- 1.1 t/yr
- 25-year saving
- £26,377
That bill suggests a larger building — see the commercial installation process for how bigger systems are sized.
Get a precise figureAssumptions, all dated: ~900 kWh per kWp per year (UK typical range 850–1,050 by region), installed cost ~£1,590 per kWp (MCS-reported England average, spring 2026, incl. 0% VAT), exported units at a 12p Smart Export Guarantee rate (rates vary by supplier and move on short notice), import price default 26p (Ofgem cap level, summer 2026). Illustrative only; your figures depend on roof, orientation, shading, usage and tariff. This tool does not store anything you enter.
Calculator FAQs
How accurate is this calculator?
It gives an indicative estimate from transparent UK assumptions: roughly 900 kWh generated per kWp per year, an installed cost near £1,590 per kWp (the MCS-reported England average as at spring 2026), and a 12p Smart Export Guarantee rate for exported units. Your real figures depend on your roof, orientation, shading, usage pattern and tariff — which is exactly what a survey establishes.
What is self-consumption and why does it matter?
Self-consumption is the share of solar you use at home rather than export. A used unit saves your full import price (around 26p as at summer 2026); an exported unit earns only your SEG rate (roughly half that). More daytime use — or a battery — means a shorter payback. The slider lets you set your daytime share.
Does the estimate include VAT?
Domestic solar installation is currently zero-rated for VAT, so the £1,590/kWp assumption is the price you would actually pay. The 0% rate runs to 31 March 2027, after which it reverts to 5%.
Is this a quote?
No. It is an indicative estimate to help you scope the idea, and it deliberately asks for no contact details. A real fixed price needs a survey of your roof, consumer unit and shading — free, and with no obligation, via the quote page.