Infrastructure Planning Blog

This week’s entry looks at four planning appeal decisions – three for solar farms and one for a data centre – plus a brief round-up of other infrastructure news.

Not a prayer

The first appeal concerns a solar farm with a generating capacity of up to 49.9MW (just below the NSIP threshold) on land south of the M20 Motorway, straddling the Channel Tunnel Rail Link. Planning permission was refused by Ashford Borough Council. The developer, EDF, appealed that decision. The appeal was dismissed. The decision notice can be found here.

At the heart of the case were competing views about the effects of the scheme on the setting of two designated heritage assets: the Church of St Martin, a Grade I listed building, and Court Lodge Farm, a Grade II* listed building. These are now a Parish Church and a farmhouse but were once a chapel and associated hunting lodge serving the Archbishop of Canterbury.

The inspector found that the presence of the solar arrays in views from these assets would be “most incongruous”. He therefore concluded that harm, albeit less than substantial harm, would be caused to the significance of the assets.

That finding engaged paragraph 215 of the NPPF, which explains that where a development proposal will lead to less than substantial harm to the significance of a designated heritage asset, this harm should be weighed against the public benefits of the proposal. There is then a need to balance this less than substantial harm against the public benefits of the proposal.

Whilst the public benefits of the scheme would be substantial, the Inspector concluded that those public benefits “do not outweigh the less than substantial harm that would be caused to the significance of the Church of St Martin and Court Lodge”.

Three things jump off the page of relevance to that conclusion:

• The Inspector was clearly not sold on scheme design: “I am firmly of the view that a better designed scheme using the appeal site in a way that avoided these impacts, could bring forward most, if not all, of the same benefits.”
• The temporary nature of the scheme was not sufficient to tip the balance in favour of the public benefits of the proposal “ I reach that conclusion notwithstanding the fact that the impact of the proposal would be temporary, albeit I note that 40 years is a relatively long time, and reversible ”.
• The public benefits of renewable energy attract substantial weight in the planning balance but won’t always prevail: “ … while Government policy generally … are supportive of renewable energy projects, there is no carte blanche ” .

Touch of Grey

Next up is a recovered appeal (that’s where the SoS makes the decision, taking into account an Inspector’s recommendation, rather than an Inspector) relating to a hyperscale data centre of up to 72,000 sqm in Buckinghamshire. Planning permission was refused by Buckinghamshire Council. The appeal was allowed and planning permission granted. The Secretary of State’s decision letter can be found here.

Of most interest is the discussion relating to development in the Green Belt, or rather the grey belt. The grey belt is a subset of the Green Belt that is considered less vital to the original purposes of the Green Belt designation. It includes previously developed land or land that does not strongly contribute to preventing urban sprawl, the merging of towns, or preserving the character of towns.

The distinction is important because showing that development would utilise grey belt land and would not fundamentally undermine the purposes of the remaining Green Belt across the area of the local plan potentially enables a proposal to dodge the stringent test under paragraph 153 of the NPPF (i.e., inappropriate development in the Green Belt should not be approved except in very special circumstances). This is on the basis that development in the grey belt is not to be regarded as inappropriate provided that all other limbs of the test in paragraph 155 of the NPPF are met.

It was noted that the pattern of built development surrounding the site meant that it did not contribute strongly to checking unrestricted urban sprawl. Nor would the site result in a material loss of visual separation between Uxbridge and Slough. Overall, the Secretary of State therefore found that the site was grey belt.

Turning to the other limbs of the test in paragraph 155 of the NPPF:

• taking into account the extent of the development site in the context of the remaining Green Belt in the area, the development would not undermine the purposes of the remaining Green Belt across the plan;
• there was a demonstrable need for this type of development and no alternative sites or search areas were available because none had been allocated in the local plan; and
• the development would be in a sustainable location by offering a genuine choice of transport modes, including a minibus service from the site and Uxbridge Underground Station for the use of workers.

Paragraph 155 of the NPPF was met, so the development was not inappropriate development for the purposes of paragraph 153. No weight was therefore attributed to Green Belt harm in the planning balance.

Staunch resistance

This appeal decision relates to a solar farm with a generating capacity of up to 49.9MW near Thrapston in Northamptonshire. Planning permission was refused by North Northamptonshire Council. The appeal was dismissed. A copy of the decision letter is here. Opposition to the proposal was led by the Save Titchmarsh, Thrapston and Upper Nene Valley Countryside and Habitats group (i.e., STAUNCH).

This one is all about habitats. The Inspector accepted STAUNCH’s evidence that the site would encroach on land used as foraging grounds by golden plover and lapwing (known as functionally linked land (FLL)). These are qualifying species of the Upper Nene Valley Gravel Pits SPA.

The development would be likely to have a significant effect on the integrity of the features for which the SPA has been designated. It was therefore incumbent on the applicant to put forward mitigation, which it did, but there were serious doubts about the efficacy of that mitigation. In particular, there was evidence that the land was used for other purposes, such as equestrianism, which would be likely to conflict with its use as FLL. Some of the land would also be crossed by a public right of way, which would be likely to interfere with its use as FLL.

The Inspector shared these concerns: “In total I have doubts as to whether it would be realistically possible to bring forward a scheme which would suitably mitigate for the loss of FLL at the appeal site”.

The scheme also fell down on highway access and safety. The Inspector noted that the traffic flows predicted seemed to be based on a significantly smaller scheme elsewhere. Accordingly, the Inspector said “I am not satisfied that in this case the evidence has demonstrated that the access to and egress from the proposed development site has been shown to be safe for the traffic likely to be generated during the construction phase of the project”.

More on grey belt

The final appeal relates to a solar farm with a generating capacity of up to 49.9MW in North Hertfordshire. Planning permission was refused by North Hertfordshire Council. The appeal was allowed and planning permission granted. A copy of the decision letter is here.

This one also engages the Green Belt tests. The parties did not agree on whether the site was grey belt. Whilst the Inspector found that the site made a moderate contribution to preventing urban sprawl, it was not a strong contribution because there were physical features around its boundary (e.g., roads, rear gardens of properties and Darley Wood) that can restrict and contain further development. The site was therefore grey belt. It was not disputed by the parties that, if the site was grey belt, the development met all of the tests in paragraph 155 of the NPPF.

Accordingly, the development would not be inappropriate development in the Green Belt, so no weight was attributed to Green Belt harm in the planning balance. This case and the data centre case highlighted above clearly show that the introduction of the concept of grey belt, via the revisions to the NPPF in December 2024, is having a tangible impact on decision making and the application of the planning balance in cases where there is an interface with the Green Belt.

Other news

Last week saw the publication of an updated National Policy Statement for Water Resources Infrastructure, in line with the Government’s ambition to update relevant NPSs within its first year. It can be found here.

I have run a comparison against the April 2023 version and there is little to set the pulse racing. There is more emphasis on the need for extra water capacity to address population growth and climate changes (section 2.2), a clarification about the scope of the alternatives assessment (section 3.5), an update on BNG (para 4.3.20), nationally designated landscapes (para 4.9.10 et seq.) and green belt (para 4.10.2).

On 9 July, PINS published its updated advice on the preparation and submission of application documents for NSIPs. It can be found here. The updates are quite narrow in scope, limited to the process for submitting an application and a new Appendix 1: Application index.

Finally, the National Infrastructure and Service Transformation Authority (NISTA) Infrastructure Pipeline went live yesterday. It can be found here and supports the Government’s UK Infrastructure: a 10 Year Plan. It provides information on public and privately delivered infrastructure projects in construction, under development or in pre-project stages where a clear strategic need has been prioritised by Government. There are 780 plans and programmes in the Pipeline at the moment. It looks like a useful tool; we’ll do some foraging over the next week and might share some observations in next week’s entry.

This publication is intended for general guidance and represents our understanding of the relevant law and practice as at July 2025. Specific advice should be sought for specific cases. For more information see our terms & conditions.