Farm Solar Panel Costs UK 2025
A comprehensive guide to agricultural solar panel costs, ROI calculations, and financing options for UK farmers considering solar installations on farm buildings.
Understanding Farm Solar Panel Costs in the UK
Investing in solar panels for your farm buildings is one of the most effective ways to reduce energy costs and future-proof your agricultural business. However, understanding the true cost of a farm solar installation requires looking beyond the headline price to consider system size, building suitability, grid connection, and long-term returns.
In this comprehensive guide, we break down everything you need to know about farm solar panel costs in the UK for 2025. Whether you are running a 150-cow dairy operation, managing a 1,000-acre arable holding, or operating intensive livestock buildings, the economics of solar have never been more compelling for British farmers.
Agricultural electricity prices have risen sharply in recent years, with many farms now paying 28p to 35p per kWh. At the same time, the cost of solar panels has fallen by over 60% in the last decade, and modern high-efficiency panels generate more electricity per square metre than ever before. This combination means that the return on investment for farm solar has reached historically attractive levels.
Farm Solar Panel Costs by System Size
The total cost of a farm solar installation depends primarily on the system size, which is measured in kilowatts (kW). Larger systems benefit from economies of scale, with the cost per kW decreasing as the system size increases.
50kW System
£45,000 - £60,000
£900 - £1,200 per kW
- 120-140 panels
- ~250m2 roof space
- ~45,000 kWh/year
- Small barns, workshops
100kW System
£80,000 - £120,000
£800 - £1,200 per kW
- 240-280 panels
- ~500m2 roof space
- ~90,000 kWh/year
- Dairy sheds, grain stores
250kW System
£200,000 - £275,000
£800 - £1,100 per kW
- 580-700 panels
- ~1,250m2 roof space
- ~225,000 kWh/year
- Large barns, multiple buildings
500kW+ System
£375,000 - £500,000+
£750 - £1,000 per kW
- 1,150+ panels
- ~2,500m2+ roof space
- ~450,000+ kWh/year
- Estate farms, poultry units
Understanding Cost Per kW for Agricultural Buildings
The cost per kW installed is the most useful metric for comparing farm solar quotes. For agricultural buildings in the UK, the typical range is £800 to £1,200 per kW. This is generally lower than domestic solar installations because farm buildings offer larger, simpler roof areas that are more efficient to install on. The cost per kW decreases with larger systems due to bulk purchasing of panels, shared inverter infrastructure, and proportionally lower labour and scaffolding costs.
When comparing quotes, always ensure you are comparing like-for-like: the same panel efficiency, inverter brand, mounting system, and scope of works. A lower headline price may reflect lower quality components or excluded costs such as grid connection or scaffolding. Use our solar calculator to get an estimate tailored to your specific farm buildings.
What Makes Up the Cost of a Farm Solar Installation?
Understanding the cost breakdown helps you evaluate quotes and identify where savings can be made without compromising on quality or performance.
Solar Panels
~40% of total costThe panels themselves represent the largest single cost component. For farm installations, we typically specify commercial-grade monocrystalline panels rated at 400W to 450W each. Higher efficiency panels cost slightly more per unit but generate more electricity per square metre of roof space, which is particularly important when roof area is limited. Panel prices have fallen significantly and continue to offer excellent value.
Inverters
~15% of total costInverters convert the DC electricity from panels into usable AC electricity. Farm systems typically use string inverters for straightforward roof layouts or optimised string inverters where shading is a concern. For systems over 100kW, central inverters can reduce per-kW costs. Quality inverters from brands like SMA, Huawei, and SolarEdge come with 10 to 25 year warranties.
Mounting and Racking
~15% of total costThe mounting system secures panels to your farm building roof. Costs vary significantly depending on the roof type: profiled metal sheet roofs are the most cost-effective to mount on, while slate or tile roofs require more complex fixings. The mounting system must be engineered to withstand local wind loads, which can be significant on exposed agricultural sites. For farms in exposed locations, additional wind bracing may be required.
Electrical Works
~10% of total costThis covers DC and AC cabling, switchgear, metering, earthing, and connection to your farm's electrical distribution board. Cable runs on farm buildings can be longer than domestic installations, particularly when the inverter location is distant from the panels. G99 or G100 grid connection applications are also included in this cost category.
Labour and Installation
~20% of total costLabour costs include site preparation, scaffolding or access equipment, panel installation, electrical commissioning, and project management. Farm installations often benefit from simpler access requirements compared to domestic properties, but larger systems require more installation days. A typical 100kW farm installation takes 5 to 7 working days on site.
Factors That Affect Your Farm Solar Cost
Roof Type and Condition
Profiled metal roofs are cheapest to mount on (£40-£60/m2 for mounting). Older roofs may need structural reinforcement before panels can be installed. A roof suitability assessment is the essential first step.
Asbestos Cement Roofing
Common on pre-1990 farm buildings, asbestos roofs require over-roofing or removal before solar installation. This can add £15,000 to £40,000 to the project depending on the roof area, but also gives you a brand new roof that will last 30+ years.
Structural Reinforcement
Older farm buildings may need structural assessment and reinforcement to support the additional weight of solar panels (approximately 12-15kg per square metre). Structural works can add £5,000 to £15,000 depending on the extent required.
Grid Connection
Systems under 50kW typically connect under the simpler G99 process. Larger systems require G100 applications to the DNO, which can take 3 to 6 months and cost £2,000 to £10,000+ depending on local grid capacity. In constrained areas, grid reinforcement costs can be significant.
Scaffolding and Access
Farm buildings often have good ground-level access, reducing scaffolding costs. However, tall grain stores or multi-storey buildings may require full scaffolding at £3,000 to £8,000. Cherry pickers or MEWPs may be used as a more cost-effective alternative on appropriate buildings.
Planning Permission
Most farm solar installations fall under agricultural permitted development rights, but listed buildings, conservation areas, or systems over 1MW may require full planning applications at £500 to £2,000+. See our planning permission guide for details.
ROI and Payback Periods for Farm Solar
The return on investment from farm solar panels is driven by two factors: electricity you consume directly (saving the full retail rate) and surplus electricity exported to the grid under the Smart Export Guarantee.
Typical Payback: 5-8 Years
Farm solar installations in the UK typically achieve payback within 5 to 8 years, with the exact timeframe depending on your self-consumption rate, electricity tariff, and system cost. After payback, the system generates essentially free electricity for its remaining 17 to 20+ years of productive life.
Key ROI Drivers:
- Self-consumption rate: Every kWh you use directly saves you 28p-35p. Aim for 50-80% self-consumption for best returns.
- Export income: Surplus electricity earns 3p-15p/kWh under the Smart Export Guarantee, depending on your chosen supplier.
- Electricity price inflation: Your savings increase each year as grid electricity prices rise, while your solar generation cost is fixed.
- System degradation: Modern panels degrade at just 0.3-0.5% per year, maintaining over 85% output after 25 years.
25-Year Financial Summary
Over a 25-year period, farm solar panels typically return three to five times the initial investment. Here is a simplified example for a 100kW system costing £95,000:
Based on 30p/kWh electricity cost, 6p/kWh SEG rate, 5% annual electricity price increase, and 0.4% annual panel degradation. Actual figures will vary.
Real Cost Examples for UK Farms
Every farm is different. Here are two detailed cost examples based on common agricultural operations we install for across the UK.
Dairy Farm: 100kW Installation
150-cow dairy operation in Somerset
Annual generation: 90,000 kWh
Self-consumption: 70% (milking twice daily aligns well with solar production)
Annual saving: £19,800 (electricity) + £1,620 (SEG export)
Payback period: Approximately 4.5 years
Arable Farm: 250kW Installation
1,200-acre arable holding in Lincolnshire
Annual generation: 225,000 kWh
Self-consumption: 55% (grain drying peaks align with summer solar, lower base load in winter)
Annual saving: £37,125 (electricity) + £6,075 (SEG export)
Payback period: Approximately 5.2 years
How to Finance Your Farm Solar Installation
There are several ways to fund a farm solar project. The right choice depends on your cash position, tax situation, and appetite for ownership versus simplicity.
Cash Purchase
Buying your solar system outright delivers the highest financial returns. You own the system from day one, benefit from all the electricity generated, and can claim capital allowances against taxable profits. With typical payback of 5 to 8 years and a 25+ year lifespan, the long-term returns are substantial.
- Highest long-term ROI (15-20%+)
- Full ownership and capital allowances
- No interest or ongoing financial commitments
Hire Purchase / Asset Finance
Hire purchase allows you to spread the cost over 5 to 10 years while still benefiting from energy savings from day one. The system becomes yours at the end of the term. Monthly repayments can be structured to be less than your energy savings, making the system cash-flow positive from month one. Agricultural lenders understand seasonal income patterns and can offer flexible terms.
- Preserve working capital
- Often cash-flow positive from month one
- Seasonal repayment plans available
Power Purchase Agreement (PPA)
With a PPA, a third party installs, owns, and maintains the solar system on your farm buildings at zero cost to you. You purchase the electricity generated at a discounted rate (typically 8p to 14p/kWh versus 28p to 35p/kWh from the grid). This is ideal for farms that want to reduce costs without any capital outlay but is typically available only for systems of 100kW and above.
- Zero upfront cost
- Immediate 10-30% savings on electricity
- All maintenance included
Government Grants and Incentives for Farm Solar
Several government schemes can significantly reduce the effective cost of farm solar installations. Understanding and accessing these programmes is essential for maximising your return.
Farming Investment Fund
The Farming Investment Fund provides grants of up to 25% towards the cost of solar panels installed on productive farm buildings. The scheme is designed to help farmers improve productivity and reduce environmental impact. Eligible items include solar PV panels, inverters, mounting equipment, and associated electrical works. The minimum grant is £15,000 (representing a project cost of £60,000), making it most relevant for systems of approximately 60kW and above.
Applications are made through the Rural Payments Agency, and our team can assist with the application process to ensure your project meets all eligibility criteria. Grant funding is competitive, so early application is advisable.
Smart Export Guarantee (SEG)
The Smart Export Guarantee requires licensed electricity suppliers with 150,000 or more customers to offer a tariff for small-scale renewable electricity exported to the grid. SEG rates currently range from 3p to 15p per kWh, depending on the supplier and tariff type. Some suppliers offer fixed-rate tariffs for a set period, while others offer variable rates linked to wholesale electricity prices.
For a 100kW farm system generating 90,000 kWh per year with 35% export, this could provide £1,890 to £4,725 in annual income, adding to the electricity savings you make from self-consumption. We help all our customers register for the most competitive SEG tariff available.
Capital Allowances and Tax Relief
Agricultural businesses can claim capital allowances on solar panel installations, providing significant tax benefits. The Annual Investment Allowance (AIA) allows 100% first-year tax relief on qualifying capital expenditure up to £1 million. This means the full cost of a solar installation can be deducted from taxable profits in the year of purchase, substantially reducing your effective cost.
For a farm paying corporation tax at 25%, a £100,000 solar installation effectively costs £75,000 after tax relief. We recommend discussing the specific tax implications with your agricultural accountant, as the benefits can be very significant.
VAT on Farm Solar Panels
VAT-registered farming businesses can reclaim VAT on solar panel installations as a business input. Solar panels installed on farm buildings used for agricultural purposes attract the standard VAT rate of 20%, which is fully recoverable for VAT-registered businesses. This effectively reduces the cost by 20% compared to the gross price.
It is important to ensure the VAT treatment is correctly applied. Panels on buildings with mixed agricultural and domestic use may attract different VAT rates on each portion. Our quotations always clearly separate the net and VAT amounts to make reclaiming straightforward for your accountant.
Running Costs and Maintenance
One of the great advantages of solar panels is their exceptionally low running costs. With no moving parts and highly durable construction, modern solar panels require minimal ongoing expenditure.
Annual Inspections and Monitoring
We recommend annual visual inspections and performance checks for all farm solar systems. This includes checking panel condition, verifying inverter operation, inspecting cable connections, and reviewing monitoring data for any performance anomalies. Most modern systems include remote monitoring as standard, allowing real-time performance tracking via a smartphone app or web dashboard. Annual inspection costs typically range from £150 to £300 for systems up to 100kW, and £300 to £600 for larger systems.
Panel Cleaning
Farm buildings are often in dusty environments, and panels near livestock can accumulate bird droppings, straw dust, and pollen. Dirty panels can lose 5 to 15% of their output. Professional cleaning once or twice a year costs £200 to £500 depending on system size and access requirements. In many cases, natural rainfall keeps panels reasonably clean, but farms with poultry or grain drying operations typically benefit from scheduled cleaning. Some farms invest in automated cleaning systems for very large installations.
Inverter Replacement
While solar panels typically last 25 to 30 years, string inverters usually have a lifespan of 10 to 15 years. Budget for one inverter replacement during the system's lifetime, at a cost of approximately £1,000 to £2,000 per inverter unit. Some inverter manufacturers now offer 15 to 25 year warranties, which can eliminate this cost entirely if specified at the time of installation. Microinverters and power optimisers typically carry longer warranties of 20 to 25 years.
Insurance
Solar panels should be added to your farm buildings insurance policy. Most agricultural insurers cover solar panels as part of the building structure, with the additional premium being modest, typically £100 to £300 per year depending on the system value. This covers damage from storms, fire, theft, and accidental damage. We recommend obtaining a written confirmation from your insurer before installation to ensure seamless coverage.
Total Annual Running Costs
For a typical 100kW farm solar system, expect total annual running costs of approximately £500 to £1,200 per year, including inspection, cleaning, insurance, and a sinking fund for eventual inverter replacement. This represents less than 5% of the annual financial benefit generated by the system. Many of our customers opt for comprehensive maintenance packages that bundle all these services for a fixed annual fee, providing peace of mind and budget certainty. View our service packages for more details.
Get an Accurate Quote for Your Farm Solar Installation
Every farm is different. Contact our agricultural solar specialists for a free, no-obligation site assessment and detailed cost breakdown tailored to your buildings.
Frequently Asked Questions About Farm Solar Costs
Find answers to the most common questions about the costs and financial aspects of installing solar panels on farm buildings.
Get a Detailed Cost Estimate for Your Farm
Ready to find out exactly how much solar panels would cost for your specific farm buildings? Our agricultural solar specialists provide free, no-obligation site assessments and detailed quotations.
Your Free Assessment Includes:
- Detailed roof survey and structural assessment
- Custom system design optimised for your energy usage
- Full cost breakdown with no hidden charges
- ROI projections and payback calculations
- Grant eligibility check and application support
- Financing options comparison for your situation