Why pig farms are ideal for solar PV
Pig units have one of the most favourable energy demand profiles of any farm sector for solar PV. Unlike arable farms where energy demand is seasonal, or some livestock farms where loads are light and variable, pig units carry continuous, predictable electrical loads all year round:
- Ventilation fans — the single largest load on most pig units, running 24/7. Pig welfare regulations require controlled atmospheric conditions, so fans cannot be switched off. Summer ventilation peaks coincide with solar peaks, maximising self-consumption.
- Heat lamps and underfloor heating — farrowing areas and weaner accommodation need supplementary heat year-round. These loads run during daylight hours, consuming solar generation directly.
- Feed augers and automated feeding — regular feed delivery throughout the day is electrically powered on most commercial units. Concentrated in daylight hours.
- Pressure washers and building services — cleaning between batches creates regular short-duration high-demand peaks, typically during working hours.
- Slurry management — pumping, agitating and moving slurry is an energy-intensive operation on most pig units, usually managed during the day.
Together, these loads create strong daytime demand throughout the year. On a well-matched system, pig farms typically achieve 65–80% self-consumption — meaning 65–80% of all electricity generated is consumed on-site rather than exported at the lower SEG export rate. This is materially higher than arable farm self-consumption (typically 40–55%) and is the primary driver of the fast payback periods achievable on pig units.
System sizing for pig farms
Correct system sizing starts with actual half-hourly meter data — not rule-of-thumb estimates based on pig numbers or building area. We request 12 months of smart meter export data as the first step of every feasibility study. That said, typical system sizes give a useful starting benchmark:
| Pig unit type | Annual kWh | Typical system | Gross cost | After FETF + AIA | Payback |
|---|---|---|---|---|---|
| 500-head finisher unit | 120,000–180,000 | 80–100 kWp | £55–£75k | £29–£40k | 1.8–2.2 yr |
| 1,000-head combined unit | 200,000–280,000 | 120–160 kWp | £84–£115k | £45–£62k | 1.7–2.1 yr |
| 1,500-head farrow-to-finish | 280,000–400,000 | 160–220 kWp | £110–£155k | £59–£83k | 1.7–2.0 yr |
| Breeding herd 200 sows | 90,000–130,000 | 65–90 kWp | £45–£65k | £24–£35k | 1.8–2.3 yr |
Assumes south-facing roof, no major structural issues, 70% self-consumption, 30p/kWh grid tariff, FETF at 40% capital, 100% AIA at 25% corporation tax. Actual figures require half-hourly meter data analysis.
Battery storage for pig farms
Battery storage can significantly improve pig farm solar economics for units with high overnight loads — farrowing houses with 24-hour heat lamps, continuous ventilation on fully enclosed buildings, and overnight feeding automation. A 30–60 kWh LiFePO4 system adds £15,000–£28,000 to project cost but typically increases self-consumption from ~65% to 80%, adding £3,000–£6,000 to annual savings. Payback on battery storage in pig applications is typically 3–4 years on top of a 1.7–2.2 year solar base payback.
For units with gas heating, smaller battery systems may suffice — the most cost-effective configuration tends to be a 20–30 kWh battery sized to absorb overnight ventilation load rather than full-site demand.
Planning and biosecurity for pig farm solar
Rooftop solar on existing pig buildings typically qualifies as permitted development under the General Permitted Development Order (GPDO) for agricultural buildings in England, Scotland and Wales. No planning application required for most barn-roof retrofits up to 1 MW.
Key pig farm-specific installation considerations:
- Biosecurity protocols — all installation teams must comply with farm biosecurity requirements including vehicle disinfection, foot dips, PPE, and restricted zone protocols. We brief every team on the specific biosecurity level before site mobilisation.
- Batch scheduling — installations are coordinated around batch clearance and cleaning periods between pig groups. Most pig buildings can accommodate a 2–4 week installation window during the clean/disinfection phase.
- Ammonia exposure — high ammonia environments in enclosed pig buildings accelerate corrosion of panel mounting components. We specify marine-grade stainless fasteners and protected cable management as standard on all pig unit installations.
- Structural assessment — older pig building steel frameworks may need load calculations before solar is added. We carry out structural assessments on every survey.
Grants for pig farm solar in 2026
Pig farms across the UK access the same grant landscape as other agricultural operations:
- ✓ FETF (England) — 40% capital, £100k cap, Feb–Mar application window. We write every application as standard. See 2026 calendar.
- ✓ Welsh FBG-E — 40% capital, £12k–£100k, quarterly windows
- ✓ Scottish CARES + SACG — interest-free loan to £150k + 40% capital grant
- ✓ NI DAERA Farm Energy Efficiency Scheme — 40% capital, annual window
- ✓ 100% Annual Investment Allowance — writes down residual cost in year one
- ✓ Smart Export Guarantee — 4–15p/kWh for surplus generation
What's included in every pig farm solar quote
- ✓ Half-hourly meter data analysis — full 12-month demand profile, self-consumption forecast
- ✓ Structural roof survey — load calcs, asbestos check, purlin inspection
- ✓ FETF / FBG-E / CARES grant application written and submitted
- ✓ DNO G99 grid connection application managed end-to-end
- ✓ MCS-certified Tier-1 panels (Trina, JA Solar, REC, LONGi)
- ✓ Marine-grade stainless fixings for ammonia environments
- ✓ 25-year panel warranty, 10-year inverter, 5-year workmanship
- ✓ IWA insurance-backed warranty — 10 years cover even if we cease trading
- ✓ Monitoring with mobile dashboard and livestock systems alert integration