120 kW Cotswolds mixed farm — workshop and grain store

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: 650-acre mixed arable and sheep farm Location: Cotswolds (Gloucestershire) Vertical: Farm Workshops System size: 120 kW across workshop and grain store Annual generation: 110,000 kWh Annual saving: £24,500 Simple payback: 6.7 years

A 650-acre mixed arable and sheep farm in the Cotswolds AONB, running cereals on the heavier ground and sheep finishing on the lighter chalk grassland. Multiple farm buildings — main grain store, machinery workshop, hay barn, fleet shed, two open-front livestock houses. Annual electricity spend before install: £36,000 across grain drying (seasonal), workshop tools (compressors, welding, refurbishment work), and farmhouse-adjacent farmyard loads.

120 kW rooftop PV split 70 kW on the machinery workshop and 50 kW on the grain store. 220 modules in total, two string inverters, single G99 application covering both buildings on the same DNO supply. Cotswolds AONB designation required a 6-week planning consultation but no formal planning permission — Class A Part 14 GPDO permitted development applied.

Modelled year-one generation: 110,000 kWh. Self-consumption averages 52% — high during grain drying season (October–November), lower during summer when workshop activity is moderate. The remainder exports under SEG, modelled here at 10.5p/kWh (flat tariffs run roughly 4–12p/kWh as at July 2026). A farm in this position exploring fleet electrification (farm EVs and light electric pickups) would lift on-site self-consumption further over the following 2–3 years.

Modelled annual savings of roughly £24,500 in year one. Simple payback at 6.7 years; 100% AIA applied year one. On a long-term estate tenancy, a project like this would run through a standard tenant-PV lease addendum — most institutional and estate landlords now have one.