Solar farms and ground-mounted arrays: the policy tests

A ground-mounted solar array on farmland needs planning permission from the local planning authority unless it is large enough to fall into the nationally significant infrastructure regime, and solar farm planning policy then turns on three questions: the quality of the agricultural land, the landscape effect, and what happens at the end of the operating life. Permitted development rights for solar in England are essentially about building-mounted panels and small standalone installations, so a commercial field array is a full application whatever its size. The policy support for renewable energy is real, and it does not remove the need to answer those three questions properly.

Which consent route applies by scheme size

Below the nationally significant infrastructure threshold, an onshore solar generating station is determined by the local planning authority as a normal planning application. Above it, the scheme goes to the Secretary of State through the development consent order process, with a very different timetable and cost.

The threshold for onshore solar in England has been changed by secondary legislation, so check the current figure before assuming which route applies. A scheme designed close to the line should be tested against the current position early, because the two routes need entirely different evidence bases.

Permitted development under Part 14 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015 covers domestic and non-domestic building-mounted installations and limited standalone equipment within a curtilage, with conditions on siting, size and prior approval in some classes. None of it delivers a field array.

Local plan renewable energy policies and their tests

Most adopted local plans carry a renewable energy policy, and most of them are permissive in principle subject to impacts. The usual tests are landscape and visual effect, effect on heritage assets and their settings, residential amenity, highways and construction traffic, ecology and biodiversity, agricultural land quality, and cumulative effect with other schemes.

Read the criteria and answer them in the same order in the planning statement. Officers write reports against policy criteria, and a submission that mirrors the policy structure is far quicker to assess than one organised around the applicant's own headings.

Some authorities also have a supplementary planning document on renewable energy or a landscape sensitivity study identifying areas where large arrays would be difficult. Those documents carry weight and they are usually available on the council's website. Discussing them at pre-application stage is worth the fee on a scheme of any size, though an officer cannot bind the council to a view.

Agricultural land quality and the best and most versatile argument

The Agricultural Land Classification system grades land from 1 to 5, with grades 1, 2 and 3a together forming best and most versatile land. National guidance encourages the use of previously developed land and poorer quality agricultural land for solar, and where a proposal uses best and most versatile land the applicant is expected to justify it.

Published grade maps are indicative and drawn at a coarse scale. Grade 3 is not subdivided into 3a and 3b on the older national maps, and that subdivision is precisely the line that matters. A site-specific soil survey by a suitably qualified soil scientist, following the published classification guidelines, is the only way to establish the grade properly.

An Agricultural Land Classification survey involves auger borings and soil pits on a grid, assessment of soil texture, depth, stoniness, wetness and gradient, and a report classifying each part of the site. It is a report type where councils expect a suitably qualified author, and professional review is strongly advised.

Two arguments help where some best and most versatile land is unavoidable. Continued agricultural use between and beneath the panels, typically sheep grazing, keeps the land in agricultural production. And the reversibility of the development, with pile-driven frames rather than concrete foundations, means the soil resource is not lost.

Landscape, screening and cumulative impact

Landscape is the reason most field arrays are refused. A landscape and visual assessment following the recognised methodology should identify the landscape character areas, the sensitive receptors, the viewpoints agreed with the officer, and the effects at year one and at year fifteen once planting has grown.

Screening deserves honesty. New hedgerow planting takes a decade to do anything, and a photomontage showing a mature hedge in year one is the fastest way to lose an officer's confidence. Show the year one condition as it will actually look.

Cumulative effect is now a standard question in areas with several consented schemes. Map the operational, consented and submitted arrays within a defined study area and assess sequential views along the roads and rights of way that connect them. A Landscape and Visual Impact Assessment that ignores a consented neighbour is an easy target for objectors.

Practical design responses that consistently help:

• Setting the array back from ridge lines and skylines, and keeping panels below the height of existing boundary vegetation where possible.
• Reinforcing existing hedgerows and field boundaries rather than creating new linear screens that read as artificial.
• Non-reflective panel finishes and dark, unobtrusive fencing set inside the boundary vegetation rather than outside it.
• Leaving margins around the array for wildlife corridors and access.
• Grouping inverters, substations and storage compounds together and screening them as a unit.

Glint and glare, grid connection and access tracks

Glint and glare assessment is a specialist study modelling reflection towards aviation receptors, road users, railways and dwellings across the solar year. Aerodrome safeguarding consultation applies where a site falls within a safeguarding zone, and the aviation authority and airport operators have established procedures for it. Commission this early, because the outcome can move panel rows.

Grid connection is the practical constraint that decides many sites. The point of connection, the cable route, whether it is underground or overhead, and the substation compound all need to be within the application or covered by a separate consent. Applications that leave the connection vague invite conditions that are difficult to discharge.

Construction traffic on rural lanes is the issue neighbours raise most often. Panel deliveries arrive over a compressed period, and abnormal loads for transformers need a route assessment. A Construction Traffic Management Plan setting out routes, timing, wheel washing and passing places addresses it before the objections arrive rather than after.

Decommissioning conditions and restoration

Permissions for solar farms are usually temporary, commonly for a period of several decades, with a condition requiring removal of all equipment and restoration of the land within a set period after generation ceases. Some authorities also seek a decommissioning bond or an obligation in a section 106 agreement.

The restoration condition should be drafted against a soil management plan. Compaction from construction traffic and cable trenching is the real risk to agricultural quality, and a plan that specifies working only in suitable ground conditions, tracked plant, defined haul routes and post-construction decompaction protects the land better than any wording about panel removal.

Biodiversity net gain applies to most development in England, and a solar site is unusually well placed to deliver it, because the land between and beneath the rows can be managed as grassland for the life of the scheme. Design the habitat plan and the grazing regime together, rather than treating the metric as a form to fill in at the end.

This is general guidance, not legal advice, and renewable energy policies, landscape studies and consent thresholds vary and change, so check the adopted local plan and current legislation with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.

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