Why pig units & finisher houses are an excellent fit for commercial rooftop PV
UK pig finisher houses and farrowing units have some of the most consistent commercial electrical demand profiles we encounter on working farms — climate-controlled finisher houses run continuous ventilation, heating in cold months, and lighting around the clock; farrowing houses add creep heating, infrared lamps, and feed-system pumps. Modern indoor pig operations to Red Tractor Pork and RSPCA Assured standards typically run 3–6 climate-controlled finisher houses on a single yard, each 60–80 metres long and 14–18 metres wide. The aggregate baseload is significant and well-aligned to PV generation — most pig finisher installs achieve 80–90% self-consumption ratios. Outdoor and free-range pig operations have lower baseload but typically still support 40–100 kW per building roof.
System sizing for pig units & finisher houses
Pig unit PV sizing: indoor finisher houses with climate control typically support 60–120 kW per building roof (depending on roof area), with strong self-consumption thanks to continuous ventilation and lighting baseload. Farrowing houses with intensive creep heating in cold months can support similar capacity. Multi-building intensive operations often support combined installs of 200–500 kW. Outdoor pig operations sit at the smaller end, typically 30–80 kW per building. Many UK pig operations also run biogas/anaerobic digestion (AD) infrastructure on the same yard — PV complements rather than competes with AD, since AD typically runs on slurry-derived gas while PV captures rooftop solar resource that would otherwise be unused.
Typical pig units & finisher houses install at a glance
- System size range
- 40–250 kW
- Panel count
- 75–460
- Roof area needed
- 250–1,500 sqm
- Project value
- £36,000–£225,000
- Typical simple payback
- 6 years
- Annual generation
- 37,000–230,000 kWh
- Annual CO2 avoided
- 9–53 tonnes
Cost and economics
Pig unit install economics in 2026: £36,000–£225,000 typical project value, 6-year simple payback, 37,000–230,000 kWh annual generation. The economic case is strengthened by 100% AIA tax relief and increasingly material supermarket supplier-audit positioning — Tesco Stronger Starts, Sainsbury's Plan for Better, M&S Plan A, Waitrose First Generation all flow through to pig supplier Scope 2 expectations. AHDB Pork's sustainability framework increasingly references on-farm renewables in producer-level scorecards.
Compare these numbers against the wider cost of farm-building solar in 2026 and the grants and finance routes available. We provide full DCF financial models with PVSyst yield modelling and 25-year IRR projections in every fixed-price proposal.
Compliance and regulation
African Swine Fever biosecurity (Pig Health Scheme, AHDB protocols) is observed throughout install — boot dips, restricted vehicle access, full crew decontamination, AHDB-approved access permissions. NVZ slurry-management and water-protection compliance unaffected by rooftop PV. Welfare of Farmed Animals Regulations 2007 unaffected. Red Tractor Pork and RSPCA Assured schemes welcome PV. Listed buildings are uncommon in pig units (most are post-1970 builds) but where present require Listed Building Consent. Modern climate-controlled houses with sealed ventilation systems require careful coordination of cable penetration to maintain biosecurity integrity.
Install programme and timeline
Pig unit install timeline: weeks 1–3, survey and biosecurity planning; weeks 3–5, design and proposal; weeks 5–7, contract and DNO G99 application; weeks 7–14, procurement and biosecurity coordination; weeks 14–18, install — 2–5 weeks for a multi-building 200–400 kW install in full ASF biosecurity protocol; week 18, commissioning. Pig batch cycles run roughly every 16–20 weeks for finishers; we schedule physical install work to coincide with empty-house cleaning windows between batches whenever possible.
A representative recent pig units & finisher houses install
A typical south Shropshire indoor pig finishing operation processing 4,500 finishers at peak across three climate-controlled finisher houses each 80m × 18m. Annual pre-install electricity spend £74,500 across continuous ventilation, climate control, feed-system pumps, and farrowing-house creep heating. We delivered 240 kW rooftop PV across all three finisher house roofs — 440 modules, three string inverters, integrated with auto-changeover to protect critical ventilation load. Full African Swine Fever biosecurity protocol observed throughout install. The system achieves 86% self-consumption thanks to year-round high ventilation and lighting baseload. Annual saving £52,000 in year one. Simple payback 5.8 years. The operation supplies a major UK retailer and the install supported retention of contract terms in the 2025 supplier review.
See more examples in our case studies library — we publish full project narratives across every sub-vertical we work in.
Key features and capabilities for pig units & finisher houses
- Climate-controlled finisher houses have high year-round ventilation and heating loads
- Farrowing-house heat lamps and creep heaters major winter loads
- Often paired with biogas/AD on intensive sites — PV complements rather than competes
- Red Tractor Pork and RSPCA Assured scheme alignment
Get a fixed-price proposal for your pig units & finisher houses install
Every quote starts with a free desk-based feasibility study from your half-hourly meter data and building dimensions. We share an indicative system size, generation forecast, self-consumption ratio, and 25-year financial model within 7 working days. If the numbers work, our engineers visit for a one-day structural and electrical survey, after which we deliver a fixed-price proposal with full PVSyst yield modelling and DCF financial model. Most pig units & finisher houses installs commission in 4–7 months from contract; combined re-roof + PV programmes add 2–3 months. Send your meter data via our quote form or contact us directly to get started.
Common questions
How much do solar panels for farm buildings cost in the UK?
For a typical UK farm-building PV install in 2026, cost per kW is roughly £900–£1,100 for systems under 50 kW (small barn, dairy parlour, equestrian arena), £800–£950 per kW for 50–250 kW systems (typical livestock shed, mid-size grain store, poultry shed), and £700–£850 per kW for systems above 250 kW (large multi-bay barns, intensive poultry or pig units, big grain stores). Combined re-roof and PV (asbestos replacement) adds £25–£45/sqm to capex but is often the only viable path on pre-2000 buildings. We provide a fixed-price proposal within 7 working days of receiving meter data and roof dimensions.
Can we put solar panels on asbestos cement barn roofs?
No — asbestos cement roofs must be replaced before any rooftop PV install. The Control of Asbestos Regulations 2012 prohibits drilling, fixing, or load-imposing on asbestos cement sheeting. The standard approach is a combined re-roof + PV project: a licensed asbestos contractor removes the cement sheets, the structure is upgraded if needed, profiled steel or membrane is installed, then PV mounts to the new roof. The PV business case routinely pays for 60–100% of the re-roof cost over the 25-year system life.
Which farm building should we install solar on first?
Prioritise by three criteria: (1) roof area and orientation — the biggest south-facing clear-span roof in sound structural condition wins; (2) on-site daytime load — dairy parlours, grain stores during harvest, intensive livestock houses, and farm workshops all have year-round or seasonal daytime baseload; (3) install access and biosecurity complexity — workshops and grain stores typically have lower biosecurity friction than poultry or pig units, but the latter often have much larger roofs. We rank each building during feasibility on payback, self-consumption, and complexity.
Will solar panels work on a curved or arched barn roof?
Generally no — modern PV requires a structural surface with adequate purlin spacing and slope (typically 5° to 35°). Curved Dutch-barn or hooped sheds need either a separate flat or pitched roof to be installed (rare), a ground-mount alternative, or — most commonly — a different building on the farm chosen as the PV host. We assess every farm holistically rather than fixating on a single building.
What grants are available for farm-building solar in 2026?
Headline schemes: 100% Annual Investment Allowance (universal — up to 25% effective tax saving year one), Sustainable Farming Incentive (SFI 2025 actions for biodiversity and agrivoltaic pairings), Farming Investment Fund (capital grants on solar-paired investments like robotic milking or grain dryers), Smart Export Guarantee (8–15p/kWh on surplus export). Welsh and Scottish farms have additional devolved schemes (Rural Investment Schemes) often with higher intervention rates than English equivalents.
Do we need planning permission for solar on agricultural buildings?
Most rooftop installs on agricultural buildings fall under Class A Part 14 GPDO 2015 Permitted Development — no planning permission needed. The exceptions are: listed agricultural buildings (Listed Building Consent required), National Parks and AONBs (sometimes Article 4 directions in force), Conservation Areas, and ground-mount above 9m × 9m × 4m height. We handle planning consultation as part of every project — typically a 4–8 week timeline if planning is required.