The North East’s farm sheds are some of the best solar sites in the region — big, unshaded steel roofs, often helpfully oriented, sitting above businesses that genuinely use electricity. But “farm solar” done from the roof inward is how the sector got its share of bad installs: arrays sized to fill the shed rather than to serve the holding. We design the other way round. Start with what the meter does, then let the roof carry as much of that as pays.
Start with the meter, not the roof
Farms differ more than almost any other commercial client, because the load profile is the enterprise. What the wires are doing at 11am decides the payback, so that is where the survey starts:
- Dairy is the strong case: milking, milk cooling and washing cycles draw power every day of the year, much of it in daylight. Refrigeration alone gives a dairy the kind of steady daytime base load that makes solar arithmetic straightforward.
- Poultry and pigs run ventilation, feeding, lighting and climate control around the clock — high self-consumption, and a genuine argument for battery storage to carry the evening load on stored daytime generation.
- Grain and potato stores are intense but seasonal: drying and cooling hammer the meter for weeks, then idle. Solar still works, but the honest design conversation is about what the array does the other forty weeks — export, other loads, or a deliberately smaller system.
- Livestock and arable holdings with modest base load are the ones we will sometimes talk out of a big array. A shed roof that could carry 100 kWp is not a reason to build 100 kWp if the holding uses a fraction of it.
On yield: a well-oriented North East shed roof generates in the 800–950 kWh per kWp band a year — we plan at 850, from modelling Durham specifically rather than quoting a national average. A south-facing shed at a typical shallow pitch models at about 841; even an east–west ridge line still returns around 770 per face.
The shed itself
A modern box-profile steel shed takes a clamp-and-bracket-mounted array with no wet trade and an install measured in days — the full engineering detail is in our sheet-roof article. Two farm-specific cautions belong here.
First, fibre cement and asbestos. Plenty of older agricultural sheds are roofed in asbestos cement sheet, and our position is the same one we hold on every building: we do not drill or fix into asbestos sheet under any circumstances. The workable answers are re-sheeting first — often the sensible moment, since a new steel roof and a solar array have similar working lives — using a different building on the holding, or a small ground array beside it.
Second, structure. Agricultural buildings vary from engineered portal frames to sheds that grew in stages, and panels plus mounting add roughly 12–20 kg per square metre. The purlin and fixing check is part of the survey, and “this bay, not that one” is sometimes the answer — cheaper to know before the scaffold arrives.
The rural grid is the constraint nobody budgets for
Farms sit at the ends of long rural feeders, and the electrical connection — not the roof — is where farm solar projects most often need real engineering judgement. Almost any array worth building exceeds the small-scale G98 threshold, so it needs a G99 connection application to Northern Powergrid, the North East’s network operator, agreed before the system can legally export. We submit it first, because on a constrained rural network the application can take longer than the installation.
Two pieces of good news that rule-of-thumb installers skip. A weak connection is not a dead end: an export-limitation scheme under the G100 standard caps what the system pushes onto the network while leaving on-site use untouched. And where the holding’s supply genuinely is the bottleneck — single-phase to the yard, a transformer at capacity — we are an electrical contractor first, thirty-plus years in, so supply upgrades, distribution boards and private wiring across the yard are our own work rather than a subcontracted mystery.
Planning: easier than most farmers expect
Rooftop solar on agricultural buildings in England is, in most cases, permitted development — the old 1 MW cap on that right was removed in November 2023 — with systems above 50 kW involving a prior-approval application to the council covering siting and glare, a lighter process than full planning permission. The exceptions are the ones you would guess: listed farmhouses and their curtilage, and some conservation-area situations. Ground-mounted arrays sit outside those rooftop rights and normally need a planning application, which is one more reason the shed roof usually wins.
Rates and tax, farm edition
Business rates first, because farms sit differently: agricultural land and buildings are generally exempt from business rates altogether, so for most working sheds the question never arises. Where a holding does have rateable premises — a farm shop, offices, diversified units — eligible onsite solar and storage is itself 100% exempt from rates in England until 31 March 2035, applied automatically at valuation. And if an array is conceived mainly to export rather than to serve the holding, the rating and planning picture changes — raise it at the survey and we will flag what needs professional advice.
On capital allowances, the farm-relevant fact is structural: many farming businesses are partnerships or sole traders, and the headline first-year allowances are for companies within the charge to corporation tax — they do not apply to income-tax businesses. What partnerships and sole traders can use is the Annual Investment Allowance: a 100% deduction on qualifying plant, solar included, up to £1 million a year. The full picture — including the special-rate classification that catches solar and the 50% first-year allowance route for companies — is in our capital allowances article; confirm your own position with your accountant, and we will give them the figures.
Batteries, backup and the honest caveat
Evening milking, overnight ventilation, cold stores that never switch off: farm loads are exactly where storage earns its place, shifting daytime surplus to the hours the holding actually uses. We install Fox ESS battery systems sized from metered consumption, and we plan around a 10–12 year working life for any battery or inverter — the panels above them are designed for 25 to 30 years, and any payback case we show has the replacement in it. And as the FAQ above says, backup through a power cut is a design decision, never a default — a standard grid-tied system disconnects in an outage by law.
Walk the yard with us
Every holding is its own case: the meter, the roofs, the supply, the plans for the next twenty years. Tell us about the farm — or start with the commercial solar page for the costs and rules in one place. If the honest answer for your holding is a smaller array than the shed could carry, or a re-roof first, or “not yet”, that is the answer you will get.