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The numbers

Five numbers. That’s the whole decision.

Cost after tax relief, the yearly saving, the payback and what you could be ahead after 25 years. Move the sliders and watch them change. Your full business case uses your own half-hourly data.

Get these numbers for my site
Offices, shops, factories, care homes, farms and leisure, 10 kWp upwards.
£8,000It is on the front of your last bill. Ex VAT is fine. Over £12,000 a month, we price it with you: custom pricing.
2How much roof do you have?
What we would fit100 kWp of solar
  • About 149 panels (Aiko, about 670 W each)
  • About 500 m² of roof, roughly 2 tennis courts
  • Makes about 95,000 kWh a year, 27% of what you use
  • With a 215 kWh battery for the 4pm to 7pm peak
What is a kWp, and can I change it?

kWp (kilowatt peak) is the size of a solar system: what the panels produce in full sun. Each kWp is about one and a half commercial panels and 5 m² of roof, and makes about 950 kWh a year in the UK. We size it to your bill and roof; your survey confirms the real figure.

Your estimate

100 kWp business solar with a 215 kWh battery
AThe kit costs£129,750£173,000 before tax relief, ex VAT
BIt saves you£31,130/yrestimated, in year one
COver 25 years£642,000estimated savings and income
DPays for itself in4.2 yrswhen savings cover the cost
EThen it’s profit£486,000estimated, after the kit and replacement parts

The kit costs £129,750. On these assumptions it could save about £31,130 a year, adding up to £642,000 over 25 years. It pays for itself in about 4.2 years, leaving you an estimated £486,000 ahead. Once it’s paid off, that’s about £1,920 a month back into the business.

Where the savings come from

Year one
  • Solar power you use on sitePower you no longer buy at about 27p£20,260
  • Spare solar you sellSold back at about 6p£230
  • Battery covers the 4pm to 7pm peak215 kWh charged at 13.3p, used instead of 47p power£7,650
  • Capacity MarketPaid for the battery being available to the grid£2,990
Total a year£31,130

Your money over 25 years

Cumulative
ProfitStill paying offPaid back

Business survey

Want these numbers for your site? We’ll bring this estimate with us.

Send us your details and we’ll call within one working day to arrange a free survey.

The kit costs
£129,750
It saves you
£31,130/yr
Pays for itself in
4.2 yrs

100 kWp business solar with a 215 kWh battery

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The assumptions, in full

Calibrated to our reference case, a holiday park in Kent on an £8,000 a month bill: 100 kWp of solar and a 215 kWh battery, £173,000 ex VAT, £129,750 after the 100% Annual Investment Allowance at 25%, saving £31,130 in year one and paying back in 4.2 years. Other sizes scale from it: solar at our published price per kWp, the battery at the same price per kWh, about 950 kWh per kWp a year from EU PVGIS falling 0.5% a year, power used on site worth about 27p, exports 6p, the battery charged at 13.3p and used instead of 47p peak power, and Capacity Market payments. On-site solar use is capped at 45% of your bill. A new inverter in year 12; the battery is retired after 15 years. Prices stay flat unless you tick the box. Tax relief depends on your profits, so check with your accountant. Estimates, not guarantees: your business case uses your own half-hourly data and roof.