The Ministerial decision on a Recovered appeal for a ‘hyperscale’ data centre in West London shows the challenges of meeting data needs in a policy vacuum and contains some lessons for anyone promoting development on a Very Special Circumstances case.
The West London Technology Park proposed a 163,000sqm, 147MW, data centre on a 52-hectare former landfill site alongside the M25, in the Green Belt. The Parliamentary Under Secretary of State (Department for Levelling Up, Housing and Communities, SoS) refused permission on appeal against refusal by Buckinghamshire Council. The reasons for doing so included harm to Green Belt, harm to the character and appearance of the area and the availability of alternative sites.
Need For Speed – Some Data
The decision recognises the significant need for short term hyperscale data centre capacity in both the specific ‘Availability Area’ (Slough AZ, SAZ) and the wider UK, driven by the rise in cloud computing, the rapid growth in Artificial Intelligence (AI)/machine learning and the rise of data analytics. ‘Hyperscaling’ means accommodating distributed computing requirements for ‘mission/business-critical’ functions in a way that can be rapidly scaled up.
The urgent need for new hyperscale data centres both in the UK and within the SAZ was not in dispute at the Inquiry – with a need for c.2,665MW of additional London data centre capacity 2022-2027. That equates to 12-15 new hyperscale data centres in the SAZ alone. The appeal scheme is one of three major data centre applications in the former South Buckinghamshire area, two of which are in the Green Belt.
The SoS gave significant weight to the substantial demand for new data centres and contribution that provision would make a significant contribution to the UK economy but refused on Green Belt harm grounds.
Hyperscale data centres need to be developed in clusters with access to high-speed connections and a resilient power network. These ‘Availability Zones’ are therefore defined by the market according to ‘power, position, and ping’. The SAZ itself lies close to digital connections running from London to the south west and across the Atlantic.
As the Council pointed out in its evidence, there is no national policy for data centres or any Government guidance on where they should be located. The Inspector acknowledged that the market has therefore dictated the strategy and sought to focus growth in areas best suited to its needs.
Alternatives and Very Special Circumstances: ‘locational demand vs locational imperative’
The availability of alternative, non Green Belt, sites was therefore a critical issue. The SoS unsurprisingly agreed that development would harm the Green Belt purposes of checking unrestricted sprawl of large built-up areas and safeguarding the countryside from encroachment. The site was within an area recently assessed as performing strongly against the 5 policy purposes for Green Belt. The M25 alongside (“a relatively new piece of infrastructure”) made little difference to the impact on openness and sense of unrestricted sprawl.
It was common ground at the Inquiry that there were no alternative sites in the SAZ, but the Inspector and the SoS accepted the Council’s line that while there is locational demand, the ‘need’ (i.e. at a London and UK level) could be met on sites in Availability Zones with land outside the Green Belt. The developer had not carried out such a wide-ranging assessment of alternative sites.
As a result the SoS also gave only moderate weight to:
- the site’s locational advantages – because its advantages could apply to any sites within wider AZs
- the absence of identified and readily available alternative sites within the SAZ.
Along with the heavy weight given to the existing character and appearance of the area, this seems to have tipped the balance in deciding to kill off the scheme.
The Inspector characterised the need for data centre capacity as short term – up to 2027 – because the speed of behavioural and technological change makes it difficult to reliably forecast beyond that point. That was accepted by the developer’s witness, but seems destined for reconsideration – notably, the SoS seems to have avoided relying on it.
One oddity of the Inspector’s decision was the weight given to the “fact that the appeal site is part of the land that was first designated as Green Belt around London in the mid 1950’s, as an essential characteristic of Green Belts is their permanence. The appeal proposal would, should it be allowed, give the impression that long standing Green Belt land can be developed. That would conflict with this essential characteristic as they would no longer be seen as permanent”. Green Belt land can be developed, as long as there are VSC. His approach would seem to be a gloss not found in the NPPF, which the SoS wisely steered clear of in agreeing with the other conclusions on Green Belt harm.
There is sometimes hand-wringing on whether data centre use is Class B8 (storage/ distribution) or something else, which can make a difference when applying Local Plan policies. The Magna Park appeal decision was clear almost 15 years ago that storage means storage in that sense. The SoS simply accepted that the West London Technology Park scheme was B8, even with the inclusion of a whopping 171 backup generators.
Local Labours Lost
Local Labour requirements have become prevalent – and sometimes financially eye watering – requirements for the grant of all sorts of planning permissions. The SoS agreed with the Inspector that the obligations requiring the use of local labour during construction, and when the site is operational and equipping local young people with the skills to be able to take advantage of the employment opportunities the appeal proposal would offer, were simply not necessary to make the scheme acceptable in planning terms.
This appears to be driven by the finding that there was insufficient direct requirement for such obligations in the adopted Local Plan itself. Although an unwelcome corollary of the Green Belt win for the Council, if applied more widely it will ensure that the specific Employment & Training requirements are more clearly set out in Local Plans when they are promoted and examined – so that the associated cost burden are properly factored into the Local Plan viability assessment (rather than being slid under the door in a post-Plan Supplementary Planning Document).
Interestingly, it was these kinds of obligations that the Inspector in the Link Park Heathrow case considered so crucial to the decision that he refused permission on the basis that they were by not properly secured by condition (wrongly, according to High Court, quashing his decision). That scheme – half the size of the West London Technology Park proposals, one junction along the M25 – has been revised and will be back with the same authority shortly.
 Appeal APP/Y0435/X/09/2103771, 2009
 Inspector’s Report paragraph 244
 Which covers parts of Buckinghamshire, Slough, Windsor and Maidenhead, Spelthorne, and Hillingdon