640 kW Lincolnshire arable — rooftop and ground-mount hybrid

Modelled worked example. The figures below are modelled from typical 2026 UK costs, yields and tariffs for this building type and system size — this is an illustrative scenario, not a named client project.

Scenario: 2,200-acre family arable farm Location: North Lincolnshire Vertical: Grain Stores System size: 640 kW (380 kW rooftop + 260 kW ground-mount) Annual generation: 612,000 kWh Annual saving: £94,000 Simple payback: 6.4 years

A 2,200-acre family arable farm in north Lincolnshire with three grain stores totalling 4,500 sqm clear-span roof area, heavy autumn drying load, and 14 acres of marginal pasture unsuitable for cropping. Mixed motivation: grid electricity cost reduction, SFI income diversification, and retailer supplier-audit positioning ahead of contract renewal.

The modelled scope is a hybrid system: 380 kW rooftop PV across two of the three grain stores (the third had a roof condition issue scheduled for replacement in 2027), and 260 kW ground-mount on the 14 acres of marginal pasture with continued sheep grazing under the panels. A 220 kWh battery system supports peak-shaving during the October–November grain drying season.

Modelled year-one generation: 612,000 kWh across the three system components. Self-consumption averages 48% across the year (high during harvest and drying season, lower during summer when crops are in the field). The 220 kWh battery cycles approximately 250 times per year, primarily time-shifting summer generation to support autumn drying peak loads.

Modelled annual savings of roughly £94,000 in year one — cost avoidance on directly-consumed generation plus SEG export income modelled at 11p/kWh. Simple payback at 6.4 years; 25-year IRR modelled at 13.8%. The SFI biodiversity bundle now stacks under the ground-mount section, generating an additional £8,500/year in environmental income.

For a producer on a major-retailer contract, an install of this scale provides exactly the credible Scope 2 reduction evidence supplier audit teams now look for at renewal.