Solar Panels for Farm Buildings

Every farm building type covered — grain stores, livestock sheds, dairy units, poultry houses and machine stores. MCS-certified installation with Class R planning support included.

Solar Panels for Farm Buildings: Every Building Type Covered

Modern UK farming operations use electricity across a diverse range of building types — from grain stores and livestock sheds to dairy units, machinery stores, farm offices and processing facilities. Each building type has different energy demands, structural characteristics and planning considerations that influence solar system design.

The common factor is opportunity. Rising grid electricity prices, strong capital allowance tax relief and Class R permitted development rights have made solar installation one of the most financially compelling investments available to farm businesses. A farm that spends £50,000/year on electricity and installs 300kW of solar across its buildings could reduce that bill by £35,000–£42,000 annually — often achieving full payback within 5–6 years.

Solar by Farm Building Type

Our surveyors have assessed farm buildings across all regions and building types. We understand the specific structural, planning and operational constraints of agricultural buildings and design systems that work within them — not against them.

Agricultural Permitted Development: Class R in Detail

Class R of the Town and Country Planning (General Permitted Development) (England) Order 2015 grants permitted development rights for ground-mounted solar on agricultural units of 5 hectares or more. The legislation also supports roof-mounted solar on farm buildings under wider agricultural PD rights. Key requirements for Class R:

• Agricultural unit must be 5 hectares or more
• Total installed capacity on the unit must not exceed 1 megawatt
• No single array may exceed 0.5 hectares in area
• Arrays must be at least 5 metres from the perimeter of the unit
• Prior approval from the local planning authority (LPA) is required
• The LPA has 56 days to determine the prior approval application
• Arrays must be removed and land restored if no longer needed for energy generation

Prior approval applications under Class R require a site plan, location plan, method statement and assessment of landscape, heritage and ecology impact. Most well-prepared applications on open agricultural land are approved. We prepare and submit Class R applications as part of our project management service.

Structural Considerations for Farm Buildings

Not all farm buildings are structurally adequate to carry a solar panel array. Steel portal frame buildings from the 1980s onwards are typically robust enough for standard panel loadings (10–15 kg/m2 for panels and racking). Older buildings — particularly traditional timber-framed barns, Victorian Dutch barns with wrought iron frames, and concrete-framed grain stores built in the 1960s — may require structural assessment.

A structural engineer's assessment is recommended for buildings over 30 years old, any building where purlins show signs of deflection or corrosion, and all timber-framed buildings. The cost of a structural assessment (typically £500–£1,500) is well justified against the cost and risk of installing a 100kW+ array on a building that proves inadequate.

Where roof mounting is not feasible — structurally weak roof, north-facing orientation, excessive shading — ground-mounted systems adjacent to farm buildings can deliver equivalent or superior generation. See our ground-mounted solar guide for full details.

Farm Energy Audit: Maximising Self-Consumption

The financial return from farm solar depends critically on self-consumption — the proportion of generated electricity consumed directly on the farm rather than exported to the grid. Solar electricity used on-site is worth the full grid import price (28–32p/kWh). Exported electricity earns the Smart Export Guarantee rate (4–15p/kWh) — significantly less valuable.

We carry out an energy audit as part of every farm solar survey. This maps each significant load — milking machinery, ventilation fans, grain dryers, refrigeration, workshop tools, EV charging — against the time of day it runs, and models how much of each load can be covered by solar generation. The output is a self-consumption forecast for each month, showing the financial return from the proposed system.

Load management strategies — running grain dryers, irrigation pumps and EV charging during peak solar hours, and shifting non-time-critical loads to morning rather than evening — can increase self-consumption from 55% to 80%+ on most farms, significantly improving financial returns.

Combining Multiple Farm Buildings

The most efficient solar projects at farm scale combine multiple buildings on a single electrical installation. A shared AC bus or DC network allows the output of arrays on several buildings to be combined at a central inverter/battery system, rather than installing separate systems per building. This reduces inverter, metering and protection relay costs significantly.

For farms approaching the 1MW Class R limit, the optimal design often involves separate grid connections per agricultural unit, allowing each unit's 1MW PD allocation to be used independently. We work with DNOs and planning authorities to structure multi-unit applications correctly.

Case Studies

Frequently Asked Questions

Optimising Solar for Different Farm Energy Patterns

The greatest return from farm solar comes from matching generation to the farm's specific energy consumption patterns. Different farming enterprises use electricity at different times and in different volumes — understanding these patterns before system design ensures maximum self-consumption and minimum export.

Dairy farms have a particularly interesting energy profile. The morning milking shift starts at 4–5am — before solar generation begins — using 50–80kW for milking and cooling simultaneously. A battery system charged from previous afternoon's solar can cover the pre-dawn milking shift, extending effective solar coverage to 80%+ of daily dairy electricity.

DNO Considerations for Rural Farm Connections

Rural farms often face the most challenging DNO connection situations in UK commercial solar. Single-phase 63A services, long cable distances from substations, and limited rural substation capacity can make export-oriented solar projects uneconomical.

The key solution is designing for maximum self-consumption. A farm system sized to match its own peak daily demand — rather than maximum roof area — typically connects to the existing supply without DNO reinforcement. A 200kW system at a farm with a 200kW peak demand on a three-phase 250A service can usually connect under G99 without additional network investment.

For farms where the grid connection genuinely cannot support export, we design battery-first systems where all generation is stored and self-consumed rather than exported. The SEG income is lost, but the capital cost saving on DNO works more than compensates on most rural sites.

Insurance and Maintenance for Farm Solar Systems

Building Insurance

Adding solar panels to farm buildings increases the insured value of the structure. Notify your building insurer before installation to ensure the solar installation is covered from day one. Most agricultural insurance policies can be extended to cover solar panels under a standard endorsement — typically adding 5–10% to the annual premium.

System Monitoring and O&M

All commercial farm solar systems are monitored via inverter data portals (SolarEdge, SMA, Fronius, Huawei). Modern monitoring systems identify underperforming strings, inverter faults and soiling losses in real time, allowing rapid maintenance dispatch. Annual yield guarantees backed by our monitoring team ensure performance over the system's design life.

Roof Cleaning

Agricultural environments — particularly livestock sheds and grain stores — produce dust, chaff, bird droppings and other soiling that can reduce panel output by 5–15% if not managed. Annual panel cleaning is recommended for farm installations, either by specialist solar cleaning contractors or with farm-based equipment (a gentle roof wash using a telescopic pole and soft brush).