BrightGridFarm energy use looks nothing like a household's, and a farm solar system that's simply sized to "cover the roof" often misses where the real value is. This guide covers how agricultural solar is actually planned, and what tends to make the biggest difference to the numbers.
Why farm solar is a different exercise to residential solar
A house has a fairly predictable daily electricity pattern. A farm's load depends entirely on what's happening on-site — refrigeration running continuously, irrigation pumps cycling with the season, milking parlours drawing heavily at specific times of day, grain dryers pulling large loads for short intensive periods. Sizing a system well means understanding that pattern, not just measuring roof area.
The first question that shapes everything else
Before sizing anything, it's worth deciding: do you want to prioritise on-site consumption, export income, or a balance of both? The answer changes the ideal system size, whether a battery makes sense, and how the whole proposal is structured.
| Priority | What this usually means for system design |
|---|---|
| Maximise consumption | System sized closer to your actual daytime load, often with battery storage to cover morning/evening milking or refrigeration peaks |
| Maximise export | Larger system sized to roof capacity, less reliant on matching your own load pattern, revenue driven by export tariff rates |
| Balanced | Mid-sized system with modest storage, covering the bulk of daytime load with a manageable export surplus |
Where farm electricity actually goes
- Refrigeration and cold storage — often the single largest continuous load, and the best match for solar since it runs all day
- Water pumps and irrigation — seasonal, but can be very high-draw during summer months
- Milking parlours — concentrated, predictable daily peaks, well suited to battery-backed solar
- Workshops and machinery — variable, harder to predict but usually daytime-weighted
- Grain drying — short, very high-intensity seasonal loads that are difficult to fully offset with solar alone, but still worth accounting for in sizing
Refrigeration is usually the best starting point
Because cold storage runs continuously through daylight hours, it's often the single easiest load to offset almost entirely with solar — a good anchor point for sizing the rest of the system around.
What system sizes actually look like
Farm systems vary enormously — a smallholding might install 10–20kWp on a single barn roof, while a larger dairy or arable operation with multiple large roof spans might install 100–500kWp across several buildings. Unlike residential solar, farm systems can often qualify for different connection and export arrangements depending on scale, which is worth discussing with your District Network Operator (DNO) early in planning.
Funding and finance considerations
Commercial and agricultural solar is typically financed differently to residential — options can include equipment finance, asset finance through agricultural lenders, or in some cases capital allowances that offset installation cost against tax. This is genuinely worth discussing with your accountant alongside your installer, since the right structure varies a lot by farm business setup.
How a farm assessment actually works
- Site assessment — roof condition, orientation, available land if ground-mount is being considered
- Load profile review — ideally using actual half-hourly consumption data if available, not just an annual total
- System design against your stated priority (consumption, export, or balance)
- DNO application for grid connection approval, which for larger systems can take longer than the installation itself
- Installation, commissioning, and ongoing monitoring
Request a farm assessment
Tell us about your buildings and your priority — consumption, export, or a combination — and we'll scope a system around it.
Request a farm assessmentFrequently asked questions
How much roof space does a farm need for a meaningful solar system?
It varies hugely by ambition — a single large barn roof (500m²+) can often support 50–100kWp on its own. The more useful starting question is your actual electricity consumption and priority, not just available roof area.
Can solar work well with grain drying's short, intense power demand?
Solar can offset a portion of grain drying load if drying happens during sunny periods, but the very high, short-burst nature of drying loads means it's rarely fully covered by solar alone — it's usually planned as a partial offset rather than the primary target.
Do farms need planning permission for solar?
Rooftop solar on agricultural buildings often falls under permitted development, though large ground-mounted arrays may need planning permission depending on scale and location. This is confirmed during the site assessment.
Is battery storage worth it for a farm?
Often yes, particularly where there are predictable daily peaks like milking times that fall outside peak solar generation hours — storage lets you shift midday solar to cover those peaks directly.
Sarah Kimani
Systems Designer at BrightGrid Energy
