Commercial Solar Panels UK (2026): Costs, Payback, Tax & Installers
Solar on a business roof pays back faster than solar on a house — higher unit rates, daytime consumption, full tax relief and a business-rates holiday all stack up. Here’s what a 20kW to 500kW system costs per kWp in 2026, the real payback maths, the planning and grid rules for commercial buildings, the finance routes if you don’t want the capital cost, and how to choose an installer who’s done it at this scale before.
Get a commercial solar proposal for your building
Free site assessment and a costed proposal from vetted commercial installers — roof survey, generation model, tax and payback figures, no obligation.
Get My Commercial Solar Proposal →★★★★★ Trusted by UK businesses
What commercial solar costs in 2026
Commercial systems are quoted per kilowatt-peak (kWp) of panels, and the rate falls sharply with size because scaffolding, design, grid application and mobilisation are largely fixed costs spread across more panels. Typical 2026 installed prices, excluding VAT:
| System size | Typical building | Panels (approx.) | Cost per kWp | Installed cost |
|---|---|---|---|---|
| 10 – 30 kWp | Shop, small office, workshop, pub | 22 – 65 | £1,000 – £1,300 | £12,000 – £35,000 |
| 30 – 50 kWp | Small industrial unit, GP surgery, garage | 65 – 110 | £850 – £1,050 | £28,000 – £50,000 |
| 50 – 100 kWp | Warehouse, car dealership, school, care home | 110 – 220 | £700 – £900 | £40,000 – £85,000 |
| 100 – 250 kWp | Distribution unit, factory, supermarket | 220 – 550 | £550 – £750 | £65,000 – £180,000 |
| 250 kWp – 1 MW | Large factory, logistics hub, farm complex | 550 – 2,200 | £450 – £650 | £130,000 – £600,000 |
What moves a quote within those ranges: roof type (a trapezoidal steel roof is the cheapest to fit; a flat roof needs ballasted frames; an asbestos-cement roof usually has to be replaced first), roof access and height, the length of the cable run to the main switchboard, whether the switchboard needs upgrading, and whether the DNO asks for an export limiter or a grid study. Panel choice matters less than at home — most commercial jobs use 550–600W bifacial or standard mono modules from Tier 1 makers, and the price difference between brands is a few pence per watt. For a sense of how these compare with domestic prices, see our solar panel cost guide.
Payback: the maths for a business
Three things make commercial payback faster than domestic. Businesses pay more per unit (20–28p/kWh on most 2026 contracts against a domestic cap around 25p, with no standing-charge subtlety). They consume during the day, when the panels are producing, so self-consumption runs at 70–90% rather than the 30–40% of a typical home. And the tax relief in the next section effectively discounts the capital cost by your corporation-tax rate. Worked example for a 100kWp system in the Midlands:
| Line | Figure | Note |
|---|---|---|
| Installed cost (ex VAT) | £75,000 | £750/kWp |
| Annual generation | ~85,000 kWh | 850–1,000 kWh per kWp depending on region and pitch — see output by region |
| Self-consumed (80%) | 68,000 kWh × 24p | £16,300 saved |
| Exported (20%) | 17,000 kWh × 8p | £1,400 earned |
| Annual benefit | ~£17,700 | Before O&M of ~£1,000/yr |
| Corporation tax saved via AIA (25%) | £18,750 | Year one, if profits allow |
| Simple payback | ~4.2 years | ~3.2 years net of the tax saving |
| 25-year benefit | £350,000+ | Assuming 2% annual price inflation, 0.5% panel degradation |
Payback bands by size are roughly 5–7 years at 20–50kWp, 4–6 years at 50–150kWp and 3–5 years above 250kWp. The single biggest variable isn’t the price — it’s your load profile. A bakery, a cold store, a data-heavy office or a manufacturer running day shifts will hit the top of those ranges; a nightclub or a warehouse that’s mostly empty in daylight won’t, and should look at a battery or a smaller system sized to base load. A good installer will ask for half-hourly meter data before quoting; if they don’t, that’s a warning sign.
Want this worked out for your building?
Send your half-hourly data and roof details; a vetted commercial installer will model generation, self-consumption and payback for free.
Get My Payback Figures →Tax relief, VAT & business rates
This is where commercial solar quietly beats every other energy-saving investment a business can make, and where most guides get the detail wrong.
| Relief | What it does | Detail |
|---|---|---|
| Annual Investment Allowance (AIA) | Deduct 100% of the cost from taxable profits in year one | Up to £1m of qualifying spend per year — covers almost any rooftop system. At 25% corporation tax, a £75,000 system saves £18,750 in year one. |
| 50% first-year allowance | For spend above the AIA limit | Solar is a special-rate asset, so it gets the 50% FYA — not 100% full expensing, whatever a salesperson tells you. The remaining 50% is written down at 6% a year. |
| Business rates exemption | Solar and batteries add nothing to your rateable value | Applies to onsite renewables from April 2023 to 31 March 2035. Before 2023 a big array could add thousands to a rates bill. |
| VAT | 20% on commercial installs | The 0% rate is domestic only. VAT-registered businesses reclaim it as normal; charities, schools and some care settings may qualify for reduced rates — take advice. |
| Climate Change Levy | Self-generated power isn’t subject to CCL | A small extra saving for energy-intensive users. |
Two practical points. AIA only helps if you have taxable profits to set it against in that year — a loss-making business or a start-up should model this carefully, and a lease or PPA (below) may suit better. And sole traders and partnerships get the same allowances against income tax, which at 40% can make the year-one saving larger than for a company. This isn’t tax advice; run the numbers past your accountant before signing.
Grants, loans & regional funding
Honest answer first: there is no national commercial solar grant in England or Wales. The government’s support for business solar is delivered through the tax system above, not cash. What does exist:
- Regional pots. Growth Hubs, combined authorities and the UK Shared Prosperity Fund run time-limited business energy-efficiency grants — schemes like Low Carbon Workspaces (Thames Valley and beyond) have covered a third of costs up to around £5,000–£10,000. Small, but real; call your local Growth Hub before you commit.
- Scotland. Business Energy Scotland offers interest-free SME loans for solar and batteries, sometimes with cashback. It’s why “commercial solar panels Scotland” is one of the cheapest projects in the UK to finance.
- Farms. Agricultural businesses have their own grant rounds — see solar panels for farms.
- Schools and public sector. Salix / Public Sector Decarbonisation Scheme funding and the GB Energy schools programme — see solar panels for schools.
- Industrial Energy Transformation Fund. For heavy energy users only, competitive rounds.
Anyone offering you “free commercial solar panels from the government” is describing a PPA — which is a perfectly good product, but it isn’t free and it isn’t a grant.
PPA, lease or buy?
| Route | Upfront cost | Who owns it | Best for | Catch |
|---|---|---|---|---|
| Buy outright | Full | You | Profitable businesses with cash or a bank facility; owner-occupiers | Capital tied up; you carry O&M |
| Asset finance / hire purchase | £0–10% | You (after term) | Keeping AIA benefits while spreading cost over 5–7 years | Interest; repayments usually still below the energy saving |
| Operating lease | £0 | Funder | Off-balance-sheet, fixed monthly cost | No capital allowances for you |
| Power Purchase Agreement (PPA) | £0 | Funder, 15–25 years | Tenants, large roofs, businesses that want cheaper power without a project | You buy the power at a fixed rate (typically 30–50% below grid); long contract; roof rights; landlord consent |
Rule of thumb: if you own the building and pay corporation tax, buying or asset-finance almost always wins on total return because of the AIA. If you’re a tenant, a charity or you’d rather not own a power station, a PPA gives you most of the saving with none of the hassle — just read the roof-rights and exit clauses carefully.
Planning rules for commercial roofs
In England, solar on a non-domestic building is permitted development up to 1MW under Class J of the General Permitted Development Order. Within that:
- Up to 50kW: no application of any kind, provided you meet the physical limits below.
- 50kW to 1MW: a prior approval application. The council has 56 days to decide whether it wants to control design and appearance, mainly the risk of glare on neighbours; if it doesn’t respond, approval is deemed granted. It’s a light process and your installer should handle it.
- Physical limits: no more than 200mm proud of a pitched roof; no more than 1m above a flat roof; not within 1m of a flat roof’s edge; not higher than the roof’s highest point.
- Listed buildings and scheduled monuments: permitted development doesn’t apply — listed building consent needed. Conservation areas and National Landscapes are allowed, including roof slopes facing a highway since the December 2023 change.
- Ground-mounted arrays over 9m² and solar carports need a full application — see ground-mounted solar and solar carports.
- Over 1MW: full planning application.
Wales and Scotland have their own (broadly similar) rules; check with the local authority. Airports are the one commonly missed issue: a big array inside an aerodrome safeguarding zone can trigger a glint-and-glare assessment. Our planning permission guide covers the domestic rules if you also have a home in mind.
Grid connection: G99, export & limits
Any commercial system needs approval from your Distribution Network Operator before installation under G99 (the small-system G98 route only covers 3.68kW per phase). For systems up to about 200kW on a three-phase supply this is usually a form and a few weeks. Above that, or on a weak rural network, the DNO may require a grid study, an export limit (you can generate what you like but only push so much back), or occasionally a contribution to network reinforcement — which can run to tens of thousands and needs to be known before you sign anything. Ask for the DNO response as a condition of the contract.
Export income is the smaller part of the return. Systems up to 5MW can access the Smart Export Guarantee; commercial rates are typically 5–15p/kWh depending on supplier and whether you’ll sign a fixed-term export deal. Some businesses do better with a private-wire or sleeved PPA, selling to a neighbour. Either way, the design goal is to size the system so you use 70–90% on site and treat export as a bonus — the same logic as our domestic export tariff guide, at scale.
Roof types, batteries & carports
Steel profile roofs (most industrial units) are ideal: rail or clamp systems, no penetrations, quick to fit. Flat roofs take east-west ballasted frames, which give up a little yield per panel but fit more panels and avoid drilling — see flat roof solar. Asbestos-cement roofs can’t legally be drilled into by most installers and are usually replaced, often with an insulated steel roof that improves the building anyway; our asbestos roof guide explains the options. Every commercial job should include a structural loading check — panels and frames add 12–20kg/m², and older portal-frame buildings were designed with little spare capacity.
Batteries make sense in three cases: a load that runs into the evening (hospitality, care homes, 24-hour operations), a site with an export limit, or a business that can earn from peak-shaving and grid-balancing services on a 100kWh-plus unit. Otherwise, commercial solar without storage usually has the better payback. See solar batteries explained and battery backup for power cuts if resilience is the driver. Solar carports over staff or customer parking combine generation with EV charging and are increasingly common on dealerships, supermarkets and offices — costlier per kWp than a roof, but they use land you already have.
Roof, carport or ground mount — which suits your site?
A free site assessment from a vetted commercial installer tells you what fits, what it yields and what it costs.
Book My Free Site Assessment →By sector: offices, warehouses, farms, schools
| Sector | Typical system | Why it works | Watch out for |
|---|---|---|---|
| Warehousing & logistics | 100kWp – 1MW | Huge simple roofs, low cost per kWp | Low daytime load — size to base load or add a PPA with a neighbour |
| Manufacturing | 50 – 500kWp | High daytime load, high unit rates, CCL saving | Roof condition; three-phase capacity; export limits |
| Offices | 20 – 100kWp | 9–5 load matches generation exactly | Flat roofs with plant; landlord/tenant split |
| Retail & supermarkets | 50 – 300kWp | Refrigeration is a perfect daytime load | Car-park carports often better than the roof |
| Hospitality & care homes | 20 – 100kWp | Seven-day load; hot water via diverter | Evening peaks — batteries pay here |
| Farms | 30 – 250kWp | Big barn roofs, cold stores, dairies; grant rounds | Weak rural grid — get the DNO answer first. See farm solar |
| Schools & public sector | 30 – 150kWp | Funding routes; strong educational case | Summer-holiday export; procurement rules. See school solar |
Choosing a commercial installer
- Commercial specialists, not domestic firms scaling up. Ask how many 50kWp-plus systems they’ve commissioned in the last two years and for generation data from three of them.
- Structural sign-off in the process. A roof-loading assessment by an engineer should be standard, not an extra.
- They handle G99 and prior approval. And they’ll tell you the DNO position before you sign, not after.
- Accreditation. MCS is required under 50kW for export payments; above that look for NICEIC or NAPIT, CHAS or SafeContractor, and ideally RECC membership. Our installer checklist applies at any scale.
- Performance guarantee and O&M. A written generation guarantee, remote monitoring, and an operations and maintenance option with response times.
- Warranties that survive. 25-year panel product warranties from a Tier 1 maker, 10-plus on inverters — see what solar warranties really cover.
- Three quotes on the same spec. Commercial pricing varies by 20–30% for identical systems; that’s £15,000 on a 100kWp job.
The bottom line
For a business that owns its building and uses electricity in the daytime, commercial solar is one of the highest-returning capital investments available in 2026. Payback of 4–7 years, a 25-year life, 100% first-year tax relief and no business rates until 2035 add up to an internal rate of return most businesses can’t get anywhere else — and the electricity price risk it removes is worth something on its own.
The process is more involved than a domestic install — half-hourly data, structural checks, G99, sometimes prior approval — which is exactly why the installer matters more than the panel brand. Start with a free site assessment and a properly modelled proposal, get three of them, and take the tax numbers to your accountant.
Get commercial solar quotes for your business
Free site assessment and costed proposals from vetted UK commercial installers — roof survey, generation model, tax and payback figures, no obligation.
Get My Commercial Solar Proposal →★★★★★ Trusted by UK businesses
Commercial solar panels: frequently asked questions
How much do commercial solar panels cost in the UK?
Commercial solar is priced per kWp and the rate falls as systems get bigger. In 2026 a 10–30kWp system on a small business roof costs roughly £1,000–£1,300 per kWp (£12,000–£35,000), 50–100kWp around £700–£900 per kWp (£40,000–£85,000), 100–250kWp around £550–£750 per kWp, and 250kWp-plus around £450–£650 per kWp. All figures exclude VAT, which is charged at 20% on commercial installations and reclaimed by VAT-registered businesses.
Are commercial solar panels worth it?
For most businesses that use electricity during the day, yes — and the case is stronger than for a home. Businesses pay 20–28p/kWh, use most of what they generate on site rather than exporting it, can deduct the full cost against profits through the Annual Investment Allowance, and pay no business rates on the installation until 2035. Payback is typically 4–7 years on a system that lasts 25–30, so a 100kWp system costing £75,000 usually returns £250,000–£350,000 over its life.
Do I need planning permission for solar panels on a commercial building?
Usually not. Roof-mounted solar on a non-domestic building is permitted development up to 1MW in England. Systems up to 50kW need nothing at all; systems over 50kW need a “prior approval” application, where the council has 56 days to consider design and glare on neighbours and approval is deemed granted if they don’t respond. Panels can’t protrude more than 200mm from a pitched roof or sit more than 1m above a flat roof or within 1m of its edge. Listed buildings always need consent, and ground-mounted arrays over 9m² need a full application.
What tax relief is there on commercial solar?
Three things. The Annual Investment Allowance lets you deduct 100% of the cost from taxable profits in year one, up to £1 million of qualifying spend — enough to cover almost any rooftop system. Above that, solar qualifies for the 50% first-year allowance as a special-rate asset (it is not eligible for 100% full expensing). And rooftop solar and batteries are exempt from business rates from April 2023 until March 2035. VAT is charged at 20% but recovered in the normal way if you’re VAT-registered.
Are there grants for commercial solar panels?
There is no national commercial solar grant in England or Wales; the support comes through tax (AIA and the business-rates exemption) rather than cash. Some regions run time-limited pots through Growth Hubs, the UK Shared Prosperity Fund and schemes like Low Carbon Workspaces, which typically cover 20–40% of costs up to a few thousand pounds — worth a call to your local Growth Hub. In Scotland, Business Energy Scotland offers interest-free SME loans for solar, which is why commercial solar is so cheap to finance there. Farms have a separate route through agricultural grant rounds.
How do I choose a commercial solar installer?
Look for a firm that specialises in commercial, not a domestic installer scaling up: they should have a structural engineer’s roof-loading assessment in their process, handle the G99 grid application and any prior-approval planning themselves, offer O&M (operations and maintenance) contracts, and show you comparable installs with generation data. MCS certification is required for systems under 50kW to access export payments; above that, look for NICEIC or NAPIT electrical accreditation, Safe Contractor or CHAS, and a performance guarantee written into the contract. Get three quotes on identical specs.
Figures are typical 2026 UK estimates for guidance only; commercial pricing, generation, payback and grid costs vary widely by site, load profile, roof and region. Tax treatment is summarised from GOV.UK capital allowances guidance and is not tax advice — confirm your position with an accountant. Planning rules describe England’s Class J permitted development as amended December 2023; Wales, Scotland and Northern Ireland differ. Always use accredited installers and obtain DNO approval before contracting.