How much do solar panels for agriculture cost?

The honest answer to "what does farm solar cost" is that it depends almost entirely on what kind of farm you are. A 30 kW dairy parlour install and a 5 MW ground-mount scheme on marginal pasture are both "farm solar", and they sit at opposite ends of a very wide range. What follows is the real picture, drawn from how we actually price and deliver agricultural installs across the UK.

Cost per kW: the headline figures

For rooftop installs, the cost per kilowatt falls as the system gets bigger, because the fixed costs of scaffolding, design, grid application and commissioning are spread across more panels. As a rough guide, rooftop systems above 100 kW typically come in at around £750 to £1,000 per kW installed. Ground-mount schemes above 500 kW are cheaper per kW again, usually £600 to £800, because the racking is simpler and there is no roof to work around. Smaller installs below 100 kW carry a higher per-kW cost, often £1,000 or more, simply because the same setup costs sit on a smaller system.

To put that in money: a 100 kW system to suit a mid-sized dairy or livestock unit lands somewhere around £80,000 to £100,000 before tax relief. A 250 kW array on a large poultry shed or arable grain store sits closer to £190,000 to £240,000. A megawatt-scale ground-mount scheme runs into the hundreds of thousands or millions, though those are usually delivered under a developer-lease model where the farm does not carry the capital cost at all.

What you actually pay by farm type

Dairy farms are the clearest case. The combination of around-the-clock milk cooling and parlour load means a well-sized array gets consumed on site rather than exported, so the savings are strong and the payback is among the fastest in UK commercial solar, typically five to six years. Arable farms are more variable: the big grain-drying load is seasonal, so the question is whether to size for that autumn peak and export the rest, or build a smaller system and add battery storage. Livestock units with large clear-span sheds and high ventilation loads, broiler and layer poultry especially, behave a lot like dairy, with high self-consumption and good payback. Horticulture and glasshouse sites, with their heavy lighting and pump loads, sit at the fast-payback end too. The cards lower down this page give the indicative figures for each.

How farms pay for it

There are three main routes, and they suit different farms. The first is a cash purchase paired with capital allowances. Most farm installs fall well within the £1m Annual Investment Allowance, which means a limited-company farm can write off the full cost of qualifying solar plant against tax in the year it is installed, an effective saving of up to 25% for companies at current corporation tax rates, with comparable relief for sole-trader and partnership farms. You can read more about the rules on the government's capital allowances guidance. For a farm with the cash and a tax bill to offset, this is usually the lowest-cost route over the life of the system.

The second route is asset finance, where the system is paid off over five to ten years. Done well, the energy saving is larger than the monthly finance payment from early on, so the install is broadly cash-flow positive without tying up the farm's own capital. The third route is a power purchase agreement or land lease, where a third party funds and owns the array and the farm either buys the power at a discount or takes a rent for the land. Ground-mount lease income on marginal land typically runs £900 to £1,300 per acre per year, well above arable rental value, and the developer carries all the capital and operational risk.

Measuring the return: payback, IRR and the export question

Simple payback, the number of years for savings to repay the capital, is the figure most farmers ask for first, and it is a fair starting point. But it ignores everything after the system has paid for itself, and a good farm array runs for 25 years or more. Internal rate of return and net present value give a fuller picture of lifetime value, and we model all three in every proposal. The single biggest variable is self-consumption: every unit you use on site is worth the full retail grid price you avoid, often 20p or more, while every unit exported earns the Smart Export Guarantee tariff, currently somewhere between 4 and 15p depending on supplier. That is why sizing the system to your real load matters so much, and why we always start from your half-hourly meter data rather than a rule of thumb.

The costs people forget

A few items sit outside the headline panel-and-inverter price, and being upfront about them avoids unwelcome surprises. Grid connection is the main one: anything above 17 kW per phase needs a G99 application to the network operator, and on capacity-constrained rural feeders that can mean both a connection charge and a wait of several months to well over a year. Where export capacity is tight, a no-export design sized for self-consumption can avoid much of this cost and delay. Structural survey and any roof strengthening, scaffolding or access equipment, and the cost of an upgraded incoming supply or new switchgear can all feature depending on the site.

The big one specific to farms is roofing. Many farm buildings from before 2000 carry asbestos cement sheeting, which cannot take panels and must be removed by a licensed contractor before any install. The usual approach is a combined strip-and-reclad to profiled steel followed by PV on the new roof. It adds cost, but the solar business case often helps fund a re-roof the farm needed anyway, so it is worth treating as one project rather than two.

Timeline and cash flow

From first conversation to commissioning, a rooftop farm install typically takes four to nine months, with the grid connection usually the longest single item. The physical install itself is short, a week or two for most rooftop systems, scheduled around your busy seasons so it does not clash with calving, lambing or harvest. Once the system is live, the savings start immediately, and for a daytime-load farm on asset finance the install is often cash-flow positive from the first or second month. Set against grid electricity prices that have stayed high since 2021, the case for farm solar is about as strong as it has been in a decade.