Commercial solar for farms

Most commercial solar economics come down to one thing: how much of the free electricity you generate you can use on site, rather than exporting it cheaply. Farms tend to score well on all the factors that drive that.

• Large, unshaded roofs. Barns, grain stores, livestock sheds and workshops often have big, simple, south-facing or east–west pitches with little shading — ideal for a low-cost array.
• A ground-mount option. If roof space is limited or the structure is not suitable, a field-edge or paddock ground-mount can host the same capacity, subject to planning and grid capacity.
• High daytime demand. Dairy, poultry, pig and horticulture operations run pumps, fans, chillers and lighting through the day, so a large share of generation is used on site at full retail value.
• Income diversification. Solar adds a predictable, long-life revenue and cost-saving line alongside farming income — covered in the diversification section.

This page focuses on rooftop and small ground-mount systems for your own use (behind-the-meter), not utility-scale solar farms leased to a developer. For the wider picture see the commercial solar hub, or compare owning versus a funded system on the buy vs PPA page.

As a planning rule of thumb, allow roughly 7 m² of usable roof per kWp of panels, and assume a UK yield of about 950 kWh per kWp per year for a well-orientated array.⁵ A ground-mount needs more room for row spacing — very roughly 1–1.25 acres per 250 kWp. Use these to sanity-check what your buildings can carry:

Size the system to your daytime demand, not just your roof. See the matching cost pages for 30 kW, 50 kW, 100 kW and 250 kW, or the full farm sector guide.

Solar generates during daylight, so its value depends on how much of your load lands in those hours. Commercial self-consumption typically runs 60–85% depending on the operation, and farms sit across that range by type:

• Dairy, poultry and pig units — near-continuous milking, milk cooling, ventilation and lighting give a strong, steady daytime base load, often at the top of the 60–85% band.
• Arable and grain — demand is more seasonal (grain drying in late summer/autumn, irrigation in summer), so self-consumption can be lower unless the system is sized to the year-round base load.
• Horticulture and packhouses — refrigeration and grading equipment run through the day and match generation well.

Every kilowatt-hour you generate and use on site avoids the full delivered grid price — commonly in the region of 24–26p/kWh for smaller non-domestic and farm contracts in 2026 once standing and policy charges are included.⁴ Exported units earn far less, so higher self-consumption is what drives the returns below.

Installed cost per kWp falls as systems get larger, because fixed costs — survey, scaffolding, grid application, project management — spread across more panels. Independent 2026 UK guidance puts small commercial systems around £900–£1,200/kWp and 100–500 kW systems around £750–£950/kWp.⁶ The table below applies a consistent, conservative method so you can compare sizes.

On these assumptions a farm array returns its cost in roughly 4–6 years and then delivers largely free electricity for the remaining 20-plus year panel life — a long-run internal rate of return that many farms find compares well with other capital projects. The single biggest variable is self-consumption: drop it and payback lengthens; add well-matched load (or storage) and it shortens. Before committing, weigh buying versus a PPA/funded route, which trades day-one savings for zero upfront cost.

Two tax points are widely misunderstood on farm solar, so treat these as a prompt to check with your accountant rather than advice:

• VAT is 20% on commercial solar, not 0%. The 0% VAT rate applies to domestic installations of energy-saving materials only.³ A commercial farm installation is standard-rated at 20%. A VAT-registered farm business normally reclaims that input VAT in the usual way, but it is a cash-flow item to plan for.
• Solar PV is special-rate plant. Because solar qualifies as a special-rate asset, it is eligible for the 50% first-year allowance for companies within Corporation Tax — not the 100% full expensing that applies to main-rate plant.¹² The remaining balance is written down in the special rate pool at 6% a year. Unincorporated farm businesses use the Annual Investment Allowance instead. Rules change, so confirm current allowances and your own eligibility with your accountant.

Beyond cutting your own bill, solar can broaden a farm's income base:

• Export income. Surplus generation is sold under a Smart Export Guarantee tariff, commonly around 12–15p/kWh in 2026 depending on the supplier — modest per unit, but a steady credit on top of on-site savings.
• Ground-mount with continued farming. Where roofs are full, a field-edge array can be combined with sheep grazing beneath the panels (agrivoltaics), keeping the land in agricultural use while it also generates.
• Predictable long-life asset. A 20–30 year generating asset hedges your single biggest controllable cost against future electricity-price moves.

For a farm, prioritise an MCS-certified installer with genuine agricultural experience: structural sign-off on older or portal-frame buildings, DNO grid application, and honest self-consumption modelling against your half-hourly data.⁵ A good proposal shows its working — assumed yield, self-consumption, tariff and export rate — so you can sanity-check payback against the table above.

• Pull 12 months of half-hourly consumption data before you quote.
• Ask for self-consumption modelled on your load, not a generic profile.
• Confirm whether a battery is genuinely justified or optional.
• Decide ownership route early — see how to choose and buy vs PPA.

PlutoHome is a neutral introducer. We are not an installer and we do not install, finance or own systems. We match your farm with one MCS-certified commercial installer suited to your site — not a list of five chasing calls. Request your farm solar quote and we will make a single, relevant introduction.