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Agrivoltaics Yield Calculator

Calculate combined PV and crop revenue from a UK agrivoltaic field. Free tool using Solar Energy UK data and Defra crop margins per hectare.

Agrivoltaics Yield Calculator

PV installed
370 kW
Annual generation
295,109 kWh
PV revenue / year
£79,679
Crop retention
95.5%
Crop revenue / year
£4,202
Total revenue / year
£83,881
Total revenue / year per hectare
£41,941
Land Equivalent Ratio
1.96

How to use this calculator

Enter seven values and the calculator returns installed PV capacity, annual kWh generation, PV revenue, crop retention percentage, crop revenue, total revenue per hectare, and the Land Equivalent Ratio:

  1. Parcel area (hectares) — only the area dedicated to dual-use, not the whole holding.
  2. Ground coverage ratio (%) — the share of land surface covered by modules. UK agrivoltaic typical 25–40 percent; utility solar farm typical 60–80 percent.
  3. Peak sun hours per day — local annual average. Use 2.4 in Glasgow, 2.6 in Manchester, 2.8 in Birmingham, 3.0 in London, 3.2 in Cornwall.
  4. System efficiency (%) — derate factor. UK installers default to 78 percent for fixed tilt.
  5. Electricity rate (£/kWh) — for self-consumption use your incoming retail rate; for export use the highest SEG tariff (typically 14–24 p/kWh) or your corporate PPA price.
  6. Crop class — shade-tolerant (lettuce, berries, herbs), moderate (brassicas, pasture, soft fruit), sensitive (wheat, barley, oilseed rape).
  7. Baseline crop revenue (£/ha) — gross margin per hectare before installing panels. Defra’s Farm Business Survey gives sector averages by region.

The output combines first-principles PV physics with shade-tolerance slopes fitted to UK and European pilot data.

Why UK agrivoltaics is finally moving

Until 2022 UK agrivoltaics was effectively confined to sheep grazing under ground-mount solar farms, with no purpose-built dual-use sites. Three things have changed since.

First, Defra’s updated land-use planning guidance in 2024 explicitly recognised that grazing or cropping under elevated panels constitutes ongoing agricultural use. That removes the long-standing risk that solar farms on Grades 1–3a agricultural land would be refused at appeal on Best and Most Versatile farmland grounds.

Second, the Sustainable Farming Incentive (SFI) round opened in 2024 includes options for integrated pest management, low-input grassland, herbal leys, and pollinator strips — all of which combine naturally with panel rows. The income from SFI payments stacks on top of grazing or crop revenue.

Third, Solar Energy UK published a Best Practice Guide for dual-use solar in 2023, giving developers, lenders, and planning officers a common reference document. Combined with MCS certification of agrivoltaic-specific racking and the Contracts for Difference 2024 round (which awarded 3.3 GW of solar at strike prices around £55/MWh), the financial case for UK agrivoltaics is now well-defined.

UK crop shade tolerance — what the trials show

The University of Reading, Cranfield University, and the Centre for Alternative Technology have run multi-year pilots under controlled-shade frames since 2018. The clearest findings:

Shade-tolerant (less than 15 percent yield loss at 35 percent panel cover):

  • Pasture grass and forage legumes — ryegrass, fescue, white clover, red clover
  • Soft fruit — strawberries, blackcurrants, raspberries, blueberries
  • Salad leaves — lettuce, rocket, chard, spinach
  • Culinary herbs — parsley, chives, coriander, mint
  • Soft fruit and herb-orientated sheep grazing systems

Moderate (15–30 percent yield loss at 35 percent panel cover):

  • Brassicas — broccoli, cabbage, kale, brussels sprouts
  • Leeks, onions, garlic
  • Pumpkins and squash
  • Potatoes (early and salad varieties)
  • Conservation grazing under solar (lower stocking rate but higher biodiversity)

Sensitive (30–50 percent yield loss at 35 percent panel cover):

  • Cereal grains — wheat, barley, oats
  • Oilseed rape
  • Sugar beet
  • Maize for forage

For most English and Welsh holdings the economically optimum dual-use design is a 25–35 percent GCR with sheep grazing or soft fruit production. Arable rotation underneath panels is usually not economic in UK conditions because cereal margins are low and the shade penalty bites hard.

A worked example — 10-hectare dairy holding in Devon

A 10-hectare south-facing parcel, 3.0 PSH, 78 percent derate, 25 p/kWh SEG export rate, 30 percent ground coverage ratio, moderate crop class (grazed pasture), £900/ha baseline gross margin (typical Defra SW grazing average).

  • Installed PV: 10 × 617 × 0.30 ≈ 1,850 kW
  • Annual generation: 1,850 × 3.0 × 365 × 0.78 = 1,580,000 kWh
  • PV revenue: 1,580,000 × £0.25 = £395,000 per year
  • Crop retention at moderate × 30%: 1 − 0.40 × 0.30 = 88 percent
  • Crop revenue: 10 × £900 × 0.88 = £7,920 per year
  • Total revenue: about £402,900 per year, or £40,290 per hectare
  • Land Equivalent Ratio: 1.0 + 0.88 = 1.88

Compare to a single-use baseline of 10 × £900 = £9,000 per year for grazing alone. The dual-use case captures about 45× the gross revenue per hectare, before financing. After amortising a £2.5 million installed cost at 5 percent over 25 years (~£175,000 per year) plus annual O&M of £15,000–£20,000, net farm income is roughly £210,000 per year — a fundamentally different scale of business.

Common mistakes when sizing a UK agrivoltaic project

  • Ignoring Best and Most Versatile farmland grading. Grades 1, 2, and 3a get extra scrutiny under NPPF paragraph 174. Commission a soil survey before committing planning costs.
  • Overspecifying ground coverage. Pushing GCR above 45 percent eliminates the dual-use planning argument and converts the site into a conventional solar farm in the eyes of the LPA. Stay below 45 percent if dual-use planning consent matters.
  • Forgetting Section 73 condition reviews. Most UK solar consents include a condition requiring continued agricultural use. Make sure the consented use matches what you actually intend to do underneath.
  • Underestimating sheep-friendly racking cost. Elevated racking with 2.4 m clearance for shepherding adds about 15 percent to install cost vs ground-hugging utility-style racks. Quote both and price accordingly.
  • Missing the SFI deadline window. SFI agreements open in defined windows. Aim to time the panel install around an SFI uplift application so the new ground-cover regime qualifies for biodiversity and herbal-ley payments.

UK incentive stacking

A typical 1.85 MW Devon dual-use project in 2026:

  • Smart Export Guarantee export at 24 p/kWh: about £380,000/year on 1.58 GWh
  • Sustainable Farming Incentive uplift (herbal leys + integrated pest management): about £5,500/year
  • Capital allowances (full expensing on PV machinery): about £350,000 first-year tax relief on £2.5M install
  • Business rates exemption for renewables on agricultural holdings (per VOA practice note): full

Contracts for Difference allocations at 5 MW+ deliver inflation-linked revenue at strike prices around £55–£60/MWh in 2024. Below 5 MW the SEG plus self-consumption route usually outperforms CfD. Always run both scenarios with a chartered renewables accountant before signing offtake.

Sources

Frequently asked questions

Is agrivoltaics allowed under UK planning rules?
Yes, but the planning route depends on size. Projects up to 1 MW can usually proceed under permitted development on agricultural land if they meet schedule 2 of the Town and Country Planning (General Permitted Development) Order. Larger schemes need full planning permission from the local authority and, above 50 MW, a Nationally Significant Infrastructure Project consent from the Planning Inspectorate. The Department for Environment, Food and Rural Affairs (Defra) updated NPPF guidance in 2024 to explicitly recognise dual-use solar — sheep grazing in particular has clear planning precedent at sites such as Larks Green and Bauchland.
How much electricity can a UK agrivoltaic field produce per hectare?
At a 30 percent ground coverage ratio — the typical UK design for sheep grazing or pasture — a south-facing fixed-tilt array delivers roughly 185 kW per hectare of installed capacity. In a 2.8 to 3.0 peak sun hour climate (most of England outside the Highlands) that produces about 145,000 to 165,000 kWh per hectare per year. Higher coverage ratios up to 50 percent can almost double the kW per hectare but reduce light to pasture and rule out most arable crops underneath.
Which UK crops work under solar panels?
Sheep grazing is the dominant model — Solar Energy UK's 2023 Land Use Report counted more than 60 commercial UK sites grazing sheep under solar. Native pasture grasses and forage legumes (white clover, red clover, ryegrass) tolerate 30–40 percent shade with less than 15 percent yield loss. Soft fruit (strawberries, blackcurrants, raspberries) does well at moderate shade. Salad crops, herbs, leeks, and brassicas have shown promise in pilot work by the University of Reading and Solar Energy UK. Cereals (wheat, barley, oats) lose 25–40 percent yield at 35 percent panel cover and are usually not economic to dual-use.
What is the Land Equivalent Ratio for UK agrivoltaics?
Dupraz et al. 2011 first quantified LER for crop-and-PV at 1.35 to 1.73 for French wheat trials. Fraunhofer ISE's APV-RESOLA Heggelbach pilot in southern Germany — climate similar to southern England — measured LER between 1.6 and 1.86 for celeriac, potato, winter wheat, and clover-grass. UK sheep-grazing case studies from the Centre for Alternative Technology and the University of Lancaster have reported LER values close to 1.3 to 1.5. Anything above 1.0 means the dual-use parcel produces more total economic output than splitting solar and farming onto two separate parcels.
Does agrivoltaics qualify for the UK Smart Export Guarantee?
Yes for systems up to 5 MW. The Smart Export Guarantee requires Ofgem-licensed suppliers to pay for excess generation exported to the grid; agrivoltaic arrays qualify on the same terms as any other PV system, provided they hold an MCS certificate and meet metering requirements under BS EN 50438. Larger projects (above 5 MW) sell power under a Contracts for Difference auction or a corporate Power Purchase Agreement. Defra's Sustainable Farming Incentive (SFI) is being updated through 2026 to add agrivoltaic-specific payment options for biodiversity and soil health under the panels.

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