High Court Delivers Judgment on Solar Farm Development Planning Permission, Emphasizing Key Legal Principles.

Citation: [2024] EWHC 367 (Admin)
Judgment on


In the case of Ian Galloway, R (on the application of) v Durham County Council, the High Court renders a judgment that touches upon several legal principles pivotal in planning law. The case primarily concerns a judicial review of a planning permission for a solar farm development. Central to this case is the interpretation of planning conditions, the statutory threshold for the capacity of energy generating stations, and the principle of strict adherence to approved plans. This article explores the nuances of these principles as they have been applied in the case, offering clarity to legal professionals on their implications.

Key Facts

The planning permission in question was for a development described as a solar farm intended to provide clean energy for up to 13,861 homes. The developer, related to Lightsource bp, put forward a planning application that underwent amendments influencing the layout and, potentially, the capacity of the solar farm. Mr. Galloway, the claimant, lives in the area where the development was proposed and submitted a judicial review against the planning permission granted by Durham County Council.

The case’s complication arose predominantly from the issue of whether the planning permission granted was for a solar farm with a capacity exceeding the statutory 50 megawatts (MW) threshold—which requires government consent rather than local planning permission—and whether it approved more panels and larger areas than required for producing the mandated energy capacity.

The court assessed several legal principles, as follows:

Statutory Capacity Threshold

The critical legal consideration was the statutory capacity threshold under which local planning authorities can approve developments without government consent. Any solar farm expected to produce energy exceeding a 50MW capacity is deemed a nationally significant infrastructure project (NSI Project), requiring development consent from the Secretary of State. The core question was the measurement method for this capacity: whether the Combined-Panels Method—measuring the capacity of solar panels—or the Combined-Inverters Method—measuring capacity of inverters—should be used.

Planning Conditions Interpretation

The case emphasized the interpretation of planning conditions, specifically the “strict accordance” condition (Condition 4) requiring development to adhere rigidly to the approved plans and the details-approval condition (Condition 12) necessitating subsequent approval of precise details for above-ground structures. The court examined whether the latter allowed for variations from the strict requirements of the approved plans.

Material Consideration

The court also evaluated whether the size of the solar farm was a material consideration, touching upon the principle of whether the Council failed to consider approving more panels over a larger area than required for a 50MW capacity. This assessment involved calculations of capacity and the Council’s duty to assess landscape harm versus benefits of renewable energy production.


The High Court arrived at the following conclusions:

  1. The Court rejected the claim that the Planning Permission unlawfully approved solar panels exceeding the 50MW capacity threshold, as the Combined-Panels Method was not the sole lawful mechanism for determining capacity.

  2. It rejected the proposition that the planning permission unlawfully incorporated a specific panel model—Trina 685 Wp—on the basis that electronic metadata should not determine a planning permission’s interpretation.

  3. The Court found that the Planning Committee should have considered whether the development involved approving a larger area than required for a 50MW capacity. This omission was determined to be an “obviously material” oversight in the planning decision-making process.

  4. As the original Planning Permission was found to be flawed due to the failure to address the material consideration of size and layout efficiency, the Court quashed the permission and the non-material amendments made thereto. The case was remitted to the Planning Committee for reconsideration.


The High Court’s judgment in Galloway v Durham County Council delineates important principles concerning the limits of local planning authority and the factors that must be considered in the planning permission process. It underscores that the combination of planning conditions entailing “strict accordance” must be viewed in light of their natural and ordinary meaning, and any amendment to planning conditions requires precise legal justification. Moreover, the ruling serves as a reminder of the imperative for planning authorities to give due regard to all material considerations, particularly when such considerations have the potential to alter the outcome of planning decisions significantly. The judgment thus provides a significant interpretive guide on planning law, reinforcing the necessity for comprehensive and transparent planning analyses.