Developers often want to increase the height of windturbines in a consented scheme. A recent court decision has confirmed the circumstances in which a full planning application is not required, saving on time and cost.

Non material variation

Avariation which is "not material" can be approved without a formal planning application(s64 in Scotland; 96A in England and Wales). It is a matter of planning judgment whether the variation is "not material", and there is no specific guidance. As wind farms are often controversial, planning officerscan be reluctant to agree that a variation is "not material".

Variation of condition

Turbineheightis often specified in a planning permissioncondition, or shown on a drawing which is referred to in a condition. There is a formal procedure for varying conditions (s42 in Scotland; s73 in England and Wales). The advantage of this procedure is that it is restricted to the acceptability of the variation, and does not involve any review of the principle of the whole scheme.

Description of development

In Finney v Welsh Ministers, the planning permission description referred to "two wind turbines, with a tip height of up to 100m". The High Court confirmed that did not prevent use of the variation of condition procedure, to vary the approved drawings condition, to refer to a new drawing showing a tip height of 125m.

Previous court decisions had upheld increases in the permitted number of dwellings, and in the size of a multi-screen cinema, but not the replacement ofa superstorewith six units.

The Court's decision was based on principles from previous caselaw:

  • fundamental alteration - would the proposed variationbe a fundamental alteration of the consented development? The Inspector had found there wouldbe no additional planning harm from the increase in height.
  • power to impose conditions - would it have been competent to imposethe proposed (varied) condition when the permission was first granted?This refers to the principle that a planning authority cannot grant planning permission with one hand and then effectively refuse planningpermission with the other by imposing an inconsistent condition.The increase in turbine height did not offend against that principle.

Section 36 schemes

For section 36 schemes (50+MW) the height is specified in the section 36 part of the consent rather than in the deemed planning permission. It is unclear whether the principle in the Finney decision would enable variation of a planning condition, or if the section 36C procedure would need to be used.

Expert advice

Applying these principles in individual projects might not be straightforward. It's worth obtainingexpert planning law advice.


Neil Collar