Farm and estate solar plays by very different rules to domestic roof solar. A 50kW ground-mount on the corner of a Suffolk field has different grants, different planning, different electricity tariffs, different payback, and different tax treatment to a 4kW roof on a Chelmsford semi. Across rural the UK that distinction matters more every year.
Where the thresholds actually sit in 2026
Up to 50kW — permitted development ceiling
50-500kW — commercial rooftop or modest ground-mount
Moves into the commercial scale. Planning consent usually required (though many local authorities in Essex, Suffolk and Cambs have permissive policies for rural businesses). Install cost £0.75-£0.90 per Wp. Connection agreement with the DNO (UKPN across most of our region) typically takes 6-10 weeks. ROI 6-8 years.
500kW-1MW — full planning + G99 connection
Commercial ground-mount or large rooftop. Full planning consent, full G99 connection application (not G98), typical DNO study adds 12-20 weeks to the programme. Cost per Wp drops to £0.65-£0.75. ROI 5-7 years. Almost always private-wire with a long-term PPA (power purchase agreement) where generation exceeds self-consumption.
Above 1MW — utility scale
Beyond typical farm-scale into utility territory. Requires a Section 36 consent for anything over 50MW (England). Full DNO or transmission-system connection study, often competitive tender for grid capacity. Cost per Wp £0.55-£0.65. ROI 4-6 years, almost entirely export-based. We partner with specialists for anything above 1MW — most of our direct work sits in the 50kW-1MW band.
Grants and funding for rural solar
Domestic PV no longer carries direct grant funding — the Feed-in Tariff closed in 2019, the SEG replaced it with an export-only mechanism. Farm and rural business solar, though, has several routes.
Farming Investment Fund
Under the Rural England Prosperity Fund, grants and funding between £5,000 and £50,000 cover up to 50% of approved project cost. Solar PV for on-farm use is eligible where it supports agricultural operations. Application windows open and close annually — our farm clients typically apply in September for spring installation.
Business Electricity Tax allowances
A registered farm or rural business can claim Annual Investment Allowance on solar PV capex — 100% first-year deduction up to £1M capital spend. For a farm paying 25% corporation tax, a £200,000 solar install effectively drops to £150,000 after tax relief. This is tax timing rather than a new grant, but it shortens payback by 18-24 months on the paper cashflow.
Private wire and PPA models
For installations above 500kW, the private-wire PPA model is increasingly common: a developer funds the install, the landowner hosts it on a 25-year lease, the landowner buys the generated electricity at a sub-grid rate. Zero capex, immediate energy-bill saving. We introduce clients to PPA providers where the scheme sense-checks.
Planning — the rural reality
Rural East Anglia planning authorities have generally been supportive of on-farm solar, with caveats. Grade 1 and Grade 2 agricultural land is now a higher bar — DEFRA guidance issued in 2024 pushes commercial solar onto Grade 3b or worse. Rooftop applications almost always pass; ground-mount on prime arable is harder. Ground-mount on lower-grade land (e.g. east-facing Suffolk clay, Cambs peat) passes routinely.
- Rooftop under 50kW on agricultural building — often permitted development.
- Rooftop 50-200kW — planning likely needed but rarely refused.
- Ground-mount below 1 hectare, Grade 3b land — straightforward.
- Ground-mount on Grade 1/2 land — expect challenge; consider alternative sites.
- Sites within AONB, SSSI or conservation area — expert input needed, typically 12-20 week consent cycles.
What we install at farm scale
For farm-scale work the kit shifts. Panels move from the 435-470W tier we put on UK roofs (JA Solar, REC) up to 550-600W commercial-tier modules (Trina Vertex TSM-NEG21C, Longi Hi-MO 7). Inverters step up from GivEnergy or Fronius hybrid to Huawei SUN2000 commercial string or SMA Sunny Tripower CORE. Mounting moves from on-roof slate hooks to GSE In-Roof or ground-mount piled-steel systems. Same physics, different scale.
The build cycle is longer too. Twelve to twenty weeks end-to-end against 2-6 weeks for a domestic install. MCS certification at farm scale comes from a different scope of the scheme — commercial MCS — but the outcome is the same. The installation is listed, the kWh generated is metered, and the export contract kicks in on commissioning day.
A worked example — 200kW grain store, Cambridgeshire
A Cambs grain-drying business we quoted in Q1 2026: 200kW south-facing rooftop on a 2020-built grain store. Capex £172,000 including scaffolding, G99 DNO connection, 15-year performance warranty, and 25-year panel warranty. Self-consumption modelled at 58% (grain drying is power-hungry in August-October peak). Annual saving £21,800 (£17,500 displaced grid + £4,300 SEG export). Paid payback: 7.9 years. Tax-relieved payback (25% CT relief): 6.0 years.
That is the kind of farm where the maths works hard. Dairy parlours, cold stores, poultry units, commercial greenhouses, and grain-drying operations all carry similar load profiles and similar payback windows.
Agricultural solar FAQs
- Is farm solar still worth doing without the Feed-in Tariff?
- Yes. Self-consumption savings alone often justify the install on a farm with steady daytime load. Add SEG export on surplus and the numbers improve further. The FiT only ever accelerated the decision; it was never the sole reason.
- Does farm solar count for business rates?
- Solar PV on agricultural buildings is currently exempt from business rates under the Non-Domestic Rating (Renewable Energy) regulations. This exemption is subject to review but has been in place since 2017 and is politically stable.
- What is G98 vs G99?
- G98 is the DNO connection agreement for installations under 16A per phase (broadly up to 11.04kW single-phase, 50kW three-phase). G99 is for anything larger. G99 requires a DNO study, costs £800-£3,500 in DNO application fees, and adds 8-20 weeks to the programme.
- Can I get grants on farm battery storage?
- Battery storage is eligible under the Farming Investment Fund on the same terms as solar, provided it supports an agricultural operation. Grants of 40-50% on eligible capex. We have seen 100-500kWh battery grants approved at Suffolk and Cambs farms in 2025.
- What maintenance does farm solar need?
- Quarterly visual inspection, annual cleaning (every 2 years minimum in East Anglia — dust accumulation affects yield by 3-6% a year if left), biannual inverter firmware check. Most systems carry 10-year inverter warranties and 25-year panel warranties. Our maintenance contract is typically 1.5-2% of capex per year.
- Can I add battery later to a farm solar install?
- Yes. Most modern commercial solar inverters (Huawei SUN2000, SMA Tripower) support battery addition via the AC-coupled route. Adding 100kWh of storage to a 200kW farm system is typically £45,000-£60,000 at 2026 prices.
Book a farm solar assessment
Farms, estates and rural businesses UK-wide can book a free site survey. We 3D-model the roof or ground footprint, pull 12 months of grid consumption, and quote a full install package in writing within two weeks. Ring freephone 0800 229 4094. Same approach, every install.
Want to find out how much you could save?
Book a free 45-minute survey. We’ll check every active grant, measure every wall, and write you a plan. Yours to keep whether you book or not.
The plan is yours to keep. Take it to two other installers if you like.