Renewables projects - will the planning permission fit the project as it evolves?

How can you amend a planning permission?

A common route for securing such amendments is through an application under section 73 of the Town and Country Planning Act 1990 (or its Scottish or Northern Irish equivalents) for non-compliance with conditions attached to the permission. Since the section 73 application is for varying specific existing conditions, it is often more efficient to use this route as opposed to making a full planning application. However, there are important limitations to section 73 which developers and planning authorities can fall foul of, and unsurprisingly a number of challenges have been brought before the courts. 

What approach do the courts take?

Important guidance on the applicability of section 73 emerged from the Court of Appeal in 2019 in Finney v Welsh Minsters [2019] EWCA Civ 1868. That case concerned a section 73 application to vary an approval for two wind turbines where the description (or “operative part”) of the development referred to “a tip height of up to 100m”. The developer sought to vary a condition to increase the tip height to 125m. The Court of Appeal held that s73 did not permit grant of planning permission where the change of condition was then inconsistent with the original description. 

The latest decision of the Court of Appeal in Test Valley BC v Fiske [2024] EWCA Cov 1541 provides further guidance on the scope of section 73 permissions, and whilst the point considered is more subtle than in Finney, it makes for useful reading. 

The Fiske decision

The judgment concerned another challenge against a clean energy project, this time a solar park. In 2017 planning permission was granted for a solar park “to include ancillary equipment, inverters, substation” and other infrastructure. After a somewhat convoluted planning history including a successful challenge against an earlier section 73 permission, a further application under section 73 was granted which amended the layout and, importantly, excluded any substation. 

The planning authority argued that this was permissible because, whilst the description of development referred to a substation, the judgment in Finney only applied where a “fundamental alteration” of the original approval had occurred. In contrast to an increase in height of a wind turbine, the omission of a substation was not in their view such a fundamental change when the permission was read as a whole.  

The Court of Appeal rejected this interpretation. The power in section 73, said the Court, is subject to a clear restriction such that it may not result in a permission where either the new description or conditions are inconsistent with the original description of development. Whether or not the change on the ground was substantial or fundamental did not in itself dictate the outcome of the application.  

Why is this new judgment important?  

The Court has further emphasised the limits of a section 73 application, and in particular the description of the decision notice is critical to the scope of a subsequent section 73 application. It does not matter whether the proposed change is significant or relatively minor; if it deviates from the original development description, a full application will be necessary.

What is TLT’s view? 

Given the varied reasons why a section 73 application might be considered during the detailed design of a project, and the often complex interplay between development description and conditions, this is unlikely to be the last word that the courts have on the issue. 

At the original application stage, care must therefore be given to the description of development in a planning application, particularly for types of development - such as solar parks, wind farms or other clean energy projects - where amendments to layout and design may be needed further down the line. Whilst the description must accurately capture the development proposed, if a need for flexibility is envisaged, the description should avoid being too limiting where possible. Often  projects will be acquired at pre-development stage with the benefit of planning permission, so as a matter of due diligence detailed consideration of the decision notice will be necessary to determine whether likely amendments will require full planning permission rather than a section 73 application, and timelines (plus costs) factored in accordingly.  

Where a section 73 application is being considered, as with many planning legal issues, no two applications are likely to be the same. An understanding of the limitations of the process is therefore critical and advice should be obtained as early as possible on whether such an application is likely to be successful or might fall foul of the rules established in these important judgments. 

This publication is intended for general guidance and represents our understanding of the relevant law and practice as at December 2024. Specific advice should be sought for specific cases. For more information see our terms & conditions.