How much does business solar cost in 2026?
Real UK prices by system size, and the number most cost guides skip: what you pay on day one depends on how you fund it, not on the sticker price.
Business solar cost by system size
Indicative installed cost, cost per kWp and simple payback for the system sizes most UK businesses build, from a small SME rooftop to a large ground-mount. Bigger systems cost less per kWp because the fixed design, scaffolding and commissioning overheads spread across more capacity. Payback is shown before tax relief; the Annual Investment Allowance usually shortens it.
| System size | Typical use | Installed cost | Per kWp | Annual saving | Simple payback |
|---|---|---|---|---|---|
| 30 kWp | Small unit / small SME | £27,000 to £33,000 | ~£1,000 | £6,000 to £8,500 | 4 to 6 yrs |
| 50 kWp | SME / small warehouse | £43,000 to £52,000 | ~£950 | £10,000 to £14,000 | 4 to 6 yrs |
| 100 kWp | Warehouse / office | £78,000 to £92,000 | ~£850 | £20,000 to £27,000 | 3.5 to 6 yrs |
| 250 kWp | Mid-size industrial | £185,000 to £215,000 | ~£800 | £50,000 to £66,000 | 3.5 to 6 yrs |
| 500 kWp | Large industrial | £350,000 to £425,000 | ~£775 | £100,000 to £130,000 | 3.5 to 6 yrs |
| 1 MWp | Large / ground-mount | £650,000 to £850,000 | ~£750 | £200,000 to £260,000 | 3.5 to 6 yrs |
Indicative 2026 ranges. Assumes about 950 kWh per kWp a year and 60 to 80% self-consumption; actual figures depend on roof, orientation, shading, load profile and tariff. Savings gross of tax relief. Last updated July 2026.
The sticker price is not what your business pays on day one
That roughly £85,000 for a 100 kWp system is the cost of owning it outright. What actually leaves your bank account this year depends on how you fund it. Pay from reserves and you meet the whole cost, but you claim up to 100% first-year tax relief through the Annual Investment Allowance and keep every pound of saving for the system's life. Spread it over hire purchase, asset finance or a business loan and you own the same system while paying from the energy it saves, over roughly three to fifteen years. Or take a Power Purchase Agreement, put in nothing at all, and just buy the power a funder generates on your roof. Same panels, three very different effects on your cashflow, balance sheet and tax bill.
See what each funding route costs your business, side by side →
What actually drives the price your business pays
The ladder above gets you to a sensible ballpark, but no two installs price the same way, and the headline figure on a quote is built from several moving parts. Knowing them is the difference between comparing offers on a level footing and being caught out by a low sticker price that quietly climbs once the installer is on the roof. For a business owner working out whether the numbers stack up, the goal is not the cheapest quote, it is the right-sized system at a defensible price that you can fund without straining cashflow.
The main cost drivers
System size is the largest single factor, and it works in your favour as it grows. A small array carries much the same design, scaffolding and commissioning overhead as a bigger one, so cost per kWp falls as capacity scales, from roughly £900 to £1,100 per kWp under 50 kWp down towards £650 to £850 above 500 kWp. That is why sizing the array to your actual daytime demand, not to the roof space you happen to have, matters as much as chasing the lowest rate. Beyond size, these are the variables that move a quote most:
- Roof condition and structure. An older roof may need repair or reinforcement before panels go on, and a structural survey confirms whether the building can carry the load. On a flat roof, the choice between ballasted and penetrative mounting changes the cost too.
- The grid connection. Anything above about 3.68 kW per phase needs a G99 application to your Distribution Network Operator before it can connect, with a statutory 45-working-day response. A straightforward connection is cheap; a constrained local network can mean a connection charge or an export limit that affects both the price and the return.
- Inverter choice. String inverters are the standard, economical option. Optimisers or microinverters cost more but earn their keep on a shaded or awkward roof.
- Cabling, switchgear and electrical works to tie the array into your existing distribution board, occasionally including a board upgrade.
The hidden costs to plan for
A credible quote accounts for scaffolding, the structural survey, the DNO application, and, on larger export, the G99 protection equipment. Watch for any roof remediation the survey flags, and for ongoing operation and maintenance. A quote that leaves these out is not cheaper, it is incomplete, and the gap usually surfaces mid-job. When you compare offers, line them up on the same scope rather than on the bottom-line figure alone.
The sticker price versus what you fund on day one
The capital cost is only half the story, because the way you fund the system decides how much of it you actually pay now. With a capital purchase you meet the full cost from reserves and own the asset outright, which gives the strongest lifetime return but ties up working capital. With hire purchase, asset finance or a business solar loan you spread the same cost across fixed instalments, so the upfront figure can fall close to zero while the total paid over the term is higher because of the finance charge. A no-upfront-cost route such as a Power Purchase Agreement removes the capital outlay entirely and you buy the power instead. The system on the roof is identical; the funding route changes the shape and timing of the payments, and which of those shapes suits you depends on your cash position, your tax profile and how long you will hold the building.
The tax that lowers your real cost
Tax relief materially cuts the net cost of an owned system, and getting the position right is where a finance-literate buyer gains an edge. Solar PV is classed as special-rate plant, so it does not qualify for 100% full expensing, which is main-rate only, nor for the 40% first-year allowance introduced from January 2026. It does qualify for the Annual Investment Allowance, giving 100% first-year relief on qualifying spend up to £1,000,000 a year, which covers most business installs outright. Above that cap, a company can use the 50% special-rate first-year allowance, with the balance written down at 6% a year in the special-rate pool. VAT on business solar is charged at 20%, and a VAT-registered business reclaims it through the normal return, so for most firms it is a timing item rather than a real cost. Rooftop solar for self-consumption is 100% exempt from business rates in England from April 2022 to March 2035, and exported units earn income under the Smart Export Guarantee. This is general information, not tax advice, so confirm your position with your accountant before you rely on any figure.
Where this site fits, and where to go next
We are independent business-solar-funding specialists, not a lender, installer or financial adviser. Our job is to help you understand the price, model it against your own bill and pick a funding route before you talk to anyone. To turn the ladder above into figures for your building, weigh the routes on the funding options compared page, put your own electricity spend into the finance calculator, and read how the numbers behave over time on the payback and ROI page. For a deeper look at the sticker price itself, the specialists at commercialsolarcostuk.co.uk break down system cost in detail, while solarpanelsforbusinesses.co.uk covers the panels and installation side. When you are ready for a costed quote on your actual roof, we pass you to vetted MCS-certified installer and funder partners.
Up to 100%
First-year tax relief on most installs via the Annual Investment Allowance (up to £1m).
Reclaimable
The 20% VAT is reclaimable if you are VAT-registered, so it is a timing cost, not a net one.
£0 rates
Rooftop self-consumption solar is business-rates exempt in England to March 2035.
Sources and official guidance
Figures on this page are based on the following primary sources. This is general information, not tax advice.
Further reading
Cost and funding questions
How can a business finance solar panels?
There are six main routes: buy outright from cash, a business or green loan, hire purchase, asset finance, an operating lease, or a Power Purchase Agreement. Owning the system, through cash, a loan or hire purchase, keeps all the savings, export income and tax relief. A PPA or lease needs little or no capital but the funder keeps the asset and the relief. The right one depends on your cash position, tax profile and how long you will hold the building, which is what the comparison and calculators here are for.
Can my business get solar with no upfront cost?
Yes. Either a PPA, where a funder owns the system and you buy the cheaper power, or 100% finance, a green loan, hire purchase or lease repaid from the energy saving. Both aim to be cash-flow positive from day one. The trade-off is that zero upfront usually means giving up some ownership, tax relief or lifetime return, so it is worth modelling the true cost of each rather than just chasing the £0 headline.
Will the monthly finance payment be less than my energy saving?
Often yes, if the annual saving plus any export income beats the annual finance or PPA cost, which is the whole self-funding case. Whether it works for you depends on system size versus your consumption, your unit price, how much power you use on site and the finance rate, so it has to be modelled for your building. The finance calculator here shows the monthly payment next to the monthly saving so you can see the net position before you commit.
What tax relief can my company claim on solar panels?
For most installs the Annual Investment Allowance gives 100% first-year relief up to £1m, which at 25% corporation tax returns about 25p per £1 spent in year one. Solar is special-rate plant, so above the £1m cap a company can use the 50% first-year allowance with the balance written down at 6% a year. Solar does not qualify for 100% full expensing, which is main-rate only, so plan around the AIA and confirm with your accountant.
With hire purchase, do I still get the tax relief even though I pay monthly?
Yes. Under hire purchase you are treated as the owner from the start, so you claim the AIA or 50% first-year allowance on the full cost in year one even though you pay in instalments. The interest element is separately deductible. It is one of the main reasons owners choose HP over a lease or PPA when they want both the relief and a spread cost.
Can I reclaim the VAT on a business solar installation?
If you are VAT-registered, yes. The 20% input VAT is reclaimable through your normal VAT return, provided the system is for business use and you hold a valid VAT invoice. The 0% domestic rate does not apply to business installs, so for most firms the VAT is a timing item rather than a real cost.
What are typical finance terms and rates for business solar?
It depends on the route: hire purchase and asset finance are commonly 3 to 7 years, business and green loans 3 to 15 years, PPAs 10 to 25 years, and leases about 5 to 15 years. Rates are priced off the Bank of England base rate plus a margin for your business's credit strength, so live pricing moves with rates and your covenant strength and is worth quoting close to the decision.
Will putting solar on the roof increase my business rates?
No. In England, qualifying rooftop solar for self-consumption is 100% exempt from business rates from April 2022 to March 2035, so it will not raise your rateable value in that window. Scotland and Wales run separate regimes, so check the local position.