Why polytunnel solar makes economic sense around Plymouth
Plymouth sits at the heart of south Devon dairy (4% of England's milk), Dartmoor commoned grazing, South Hams horticulture and emerging vineyard estates. The region's working farms — many tenanted from institutional landlords like Duchy of Cornwall — typically run multi-building holdings with significant on-farm electrical demand. Polytunnel installations near Plymouth benefit from year-round daytime baseload that aligns well with PV generation: Heated glasshouses and protected horticulture have massive supplementary lighting and heating loads. For a typical polytunnel in the Plymouth area in 2026, expect a system in the 100 kW–2 MW range, project value £90,000–£1.8m, and simple payback of 5.5 years — pulled to roughly 4.0–5.0 years after 100% Annual Investment Allowance tax relief for incorporated farms.
Typical polytunnel install specification for the Plymouth region
A representative polytunnel install for a working farm near Plymouth delivers around 100 kW of capacity across roughly 600 square metres of roof area. The system would generate approximately 90k kWh per year and offset 20 tonnes of CO2 annually. Agrivoltaic translucent-panel installs need agronomic trial alongside structural assessment. Polytunnel structural reinforcement often required for rooftop PV — typically frame upgrade or perimeter ground-mount alternative. Defra and NFU horticulture engagement increasing.
Indicative polytunnel install around Plymouth
- System size range
- 100 kW–2 MW
- Panel count
- 185–3,700
- Roof area needed
- 600–12,000 sqm
- Project value
- £90,000–£1.8m
- Typical simple payback
- 5.5 years
- Annual generation
- 92,000–1.85m kWh
- Grid connection DNO
- National Grid Electricity Distribution
Plymouth-area planning and grid context
Polytunnel solar installations near Plymouth typically fall under Class A Part 14 GPDO 2015 Permitted Development — no formal planning permission is required for rooftop PV on agricultural buildings. Plymouth City Council planning officers handle any required pre-application consultations efficiently, particularly for buildings outside Conservation Areas and AONBs. Grid connection is via National Grid Electricity Distribution, with G99 study timelines of 65–90 working days and full connection windows of 6–14 months on most rural feeders around Plymouth. We submit G99 applications immediately after structural survey to start the clock; for export-constrained sites we design "no-export" self-consumption systems that connect in 6–8 weeks.
Polytunnel solar in Plymouth — key features
- Heated glasshouses and protected horticulture have massive supplementary lighting and heating loads
- Vertical farming and CEA sites exceptionally good PV fit
- Agrivoltaics over polytunnels emerging quickly (translucent panels, semi-shade-tolerant crops)
- Soft fruit, salads, ornamentals — supermarket-facing producers under Scope 3 pressure
Combined re-roof and PV for older Plymouth-area polytunnel buildings
Many polytunnel buildings around Plymouth pre-date 2000 and carry asbestos cement roof cladding. Under Control of Asbestos Regulations 2012, asbestos cement cannot be retrofitted with PV. The right move is a combined re-roof + PV project: HSE-licensed asbestos removal (£30–£50/sqm), profiled steel re-cladding (£45–£80/sqm), then PV install on the new roof. We've delivered combined re-roof + PV across South West on polytunnel buildings, with the PV business case routinely paying for 60–100% of the re-roof cost over the 25-year system life.
How we deliver polytunnel solar in Plymouth
Every project starts with a free desk-based feasibility study. Send us your half-hourly meter data and building dimensions (or aerial drone images), and 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 the Plymouth-area farm for a one-day structural and electrical survey. We deliver a fixed-price proposal with full PVSyst yield modelling and DCF financial model. From contract, typical timeline is 4–7 months for rooftop installs and 6–9 months for combined re-roof + PV. We schedule physical works around the farming calendar — calving, lambing, harvest, and shift patterns specific to your operation.
See more detail on our polytunnel solar specialist page or our wider Plymouth farm-building solar coverage.
Frequently asked questions
How much does a polytunnel solar install cost in Plymouth?
A typical polytunnel install in Plymouth ranges from £90,000–£1.8m, depending on roof area, electrical capacity and whether re-roofing is required first. Cost per kW: £800–£1,000 for sub-100 kW, £750–£900 for 100–250 kW, £700–£850 for above 250 kW. We provide a fixed-price proposal within 7 working days of receiving your half-hourly meter data.
How long does a polytunnel install take in Plymouth?
From contract to commissioning, typically 4–7 months for a rooftop install — including the 6–14 month G99 grid connection process from National Grid Electricity Distribution, which runs in parallel. Combined re-roof + PV adds 1–3 months. Physical install work on a single building is 1–4 weeks scheduled around your farming calendar (calving, lambing, harvest).
What grants are available for Plymouth-area farm solar?
100% Annual Investment Allowance (universal, up to 25% effective tax saving year one), Smart Export Guarantee at 8–15p/kWh on surplus, Sustainable Farming Incentive 2025 actions for biodiversity-paired installs. Farming Investment Fund grants are sometimes available when solar is paired with other capital items (robotic milking, grain dryers). Welsh and Scottish farms have additional devolved schemes.
Do I need planning permission for polytunnel solar in Plymouth?
Most rooftop installs on agricultural buildings near Plymouth fall under Class A Part 14 GPDO 2015 Permitted Development — no planning permission required. Listed buildings, AONB designations, and ground-mount above 9m × 9m × 4m height need full planning. Plymouth City Council planning officers are familiar with farm-building PV — we handle any consultation as part of the project.
Can we install solar on asbestos cement roofs near Plymouth?
No — asbestos cement must be removed by HSE-licensed contractors first under Control of Asbestos Regulations 2012. The standard solution is a combined re-roof + PV project, where the PV business case routinely pays for 60–100% of the re-roof over the 25-year system life. We deliver this routinely across South West.
How long does a G99 grid connection take from National Grid Electricity Distribution?
National Grid Electricity Distribution typically quotes 65–90 working days for the technical study, with full connection timelines of 6–14 months on most rural feeders (up to 18 months on capacity-constrained networks). We submit G99 immediately after structural survey to start the clock. For export-constrained sites we design "no-export" systems sized for self-consumption that complete in 6–8 weeks instead.