Infrastructure Planning Blog

This week's bumper blog marks the switch-on of biodiversity net gain (BNG) for nationally significant infrastructure projects (NSIPs), takes a look at the draft National Policy Statement (NPS) for data centres, analyses the latest development consent order (DCO) decision for the Sea Link project, and sets out what the Budget had to say about infrastructure.

BNG switch on

Mandatory BNG now applies to applications for DCOs made from this week onwards.  That means it should be taken into account right from site selection and project design. Applications will need an outline biodiversity gain plan and a few extra requirements in their draft DCOs; we will be monitoring the Planning Inspectorate website for the first ones and what their new documents look like.

There was a minor run on applications just before mandatory BNG kicked in, with two applications being made on Friday 30 October. A third originally stated to be being made in October has been delayed to May 2027.

At a launch event at our office on Monday, the mood was positive but there were a lot of questions at the Q&A session. All the speakers emphasised building BNG into project considerations as early as possible as it should affect design, cost, environmental assessment and contracts.  I was struck by how the biodiversity baseline may have to be updated as things change during the examination of the application, whether it is project design changes or alterations to the mitigation being provided.  This is now reflected in updated advice from the Planning Inspectorate - expect the outline biodiversity gain plan to be a document that gets regularly updated during the examination like the draft DCO and land interests tracker. We have written more about what the BNG changes mean for infrastructure developers here.

Draft NPS on data centres

A draft NPS covering data centres has been published for consultation; the consultation runs until 8 January 2027.  The draft can be found here.

Of note is that it is written by a government department that hasn't been involved in the DCO regime before, so-called BIST (the Department for Business, Innovation, Science and Trade), implying that that Secretary of State (SoS) will be taking the decisions on applications. The style is a bit different - continuous paragraph numbering, for example, and I was confused by '3-Government Policy' - what are the other two governments, is this a devolution thing? - before realising that was just the chapter 3 heading.

It should be read alongside the government's 'Data Centre Covenant', published on Budget Day. It requires data centres to lower electricity bills, invest in improving local communities, adhere to the highest environmental standards, create jobs and apprenticeships, drive reindustrialisation and strengthen Britain's security. It's not often you get a 19-letter word in a policy document. These tests apply in the NPS as well.

It repeats the guidance that data centres requiring at least 100 MW of energy are likely to be considered nationally significant and get a s35 direction bringing them into the DCO regime.  

The biodiversity gain statement for data centres will be revoked and its text included directly in the NPS once designated, a process presumably to be repeated for other NPSs as they are amended.

The NPS will apply to eligible data centre projects of all types, the types being Enterprise, Colocation, Hyperscale and Edge. Now you know - see paragraph 47 for an explanation. The draft NPS also uses 'compute' as a noun to mean 'computational resources', which takes a bit of getting used to.

Data centres will be considered to be of 'critical national importance'.  Note that this is for security purposes and is not the same as saying they are 'critical national priority' like renewable energy NSIPs, but the text in paragraphs 82-83 suggests they will be treated the same.

The justifications given for UK capacity for data centres rather than overseas in paragraphs 75-76 include the sensitivity of information held by them and the minimisation of latency affecting transaction speed, important for financial transactions – and social media, apparently. And paragraph 96 says upgrading existing facilities and using overseas ones are complementary to new domestic facilities, i.e. we need all of it.

The document says 'applicants should ensure that all relevant stakeholders (including local communities) are consulted prior to application' (para 110) and then links to withdrawn guidance on the pre-application process, which is slightly curious given that pre-application consultation has been abolished.

On Environmental Impact Assessment (EIA), the draft says the Rochdale envelope approach should be used when precise details are unknown, 'including the cooling method, and the energy generation'. Clustering is encouraged but its impacts should be assessed (121).

The draft goes beyond BNG to ENG (environmental net gain) (127-128). It refers to National Planning Policy Framework (NPPF) policy DP3 on design, which is unusual. Projects are expected to have a 'power usage effectiveness' of 1.3 or better. This is a data centre term corresponding to the ratio of total energy consumption to IT equipment use, and here 'better' means lower than 1.3.

Interestingly if electricity generation is used just for the data centre and does not leave the facility, NPS EN-1 does not apply to it, it's called 'Behind the Meter' (BtM) power. A new temporary framework on BtM power is to be issued and will only be allowed for 'exceptionally strategic' data centres - it should only be used when it cannot reasonably be avoided, must only be a temporary solution and mitigation for impacts on carbon emissions must be set out.

For climate change resilience purposes data centres should be assumed to last more than the standard 15-20 years and must show 'energy resiliency'. On grid connections, having one is not a pre-requisite, but it is at the applicant's risk of not getting one and applications need to set out where energy is expected to be sourced.

Although environmental permitting operates under a separate regime, the pollution control authority will need to be satisfied that potential releases can be adequately regulated and cumulative effects of pollution would not make the development unacceptable. So the two regimes are not considered to be entirely separate, an issue of much debate in the past.

There's quite a bit on security, perhaps more than usual because BIST is responsible for it.  Consent may be withheld if there are concerns about financial viability (para 114).

Section 6 on 'generic impacts' is indeed fairly generic and typical of NPSs. There's not much extra on water usage despite data centres' reputation for using a lot, although paragraph 417 mentions waterless cooling systems.

Sea Link decision

The decision on the Sea Link DCO application was consented on time on Friday 30 October. This is for a 122km offshore electricity cable with a 12km onshore section in Suffolk and a 5km one in Kent promoted by National Grid.

This application was notable for attracting the second-highest number of relevant representations, over 6,000. The one with the most, Brig y Cwm in Wales, was withdrawn during the examination so this one is the highest to get consent.

The Examining Authority recommended approval. The decision letter refers to the first information request issued during the decision stage 41 times, suggesting there was a lot of further information requested by the SoS - the heading 'matters resolved through consultation', i.e. at the decision stage, is used a few times. After all that, however, the SoS ascribed the same weight in the planning balance as the ExA to every factor.

Once again 'little' weight is corrected to 'limited' weight. There was a debate as to whether irreplaceable subtidal chalk counted as irreplaceable in planning terms. The SoS included a requirement in the DCO that if loss or deterioration of the habitat could not be avoided, it should be considered irreplaceable habitat and needs a compensation strategy to be agreed (see paragraphs 4.27-4.28).

It's not every decision letter that refers to hovercraft, but this one does – up to three emergency hovercraft would be on standby for use during construction in emergencies. What constituted an emergency was pushed down the line to be decided later by the Marine Management Organisation.

There was a concern about agricultural land classification being based on predictive modelling rather than sampling, but Natural England eventually welcomed strengthened commitments on surveying; agriculture and soil impacts still carried moderate negative weight.

There was a concern about bird collisions with overhead lines, but the strengthening of a commitment to add bird diverters if more collisions occurred than was predicted satisfied the SoS.

The applicant wanted to use the new Department for Energy Security and Net Zero (DESNZ) 'post consent unit' for discharging requirements that was in the process of being set up – the local authorities who would otherwise have discharged the requirements objected to this saying it was premature. The SoS agreed to be the discharging authority for the majority of the requirements as set out in a special schedule 20 listing who discharges what.

Budget

There were a few infrastructure-related announcements in the Budget on 28 October. The main Budget document is here.

• Competition in onshore electricity networks to be introduced (see paragraph 4.26),
• The Fingleton review of nuclear consenting is to be extended to other sectors (4.39) including a review of rail infrastructure costs,
• Legislation at the earliest opportunity will let Parliament designate and authorise infrastructure projects (4.39); an
• There will be use of 'Planning and Infrastructure Act powers' to prioritise strategic projects' electricity connections (4.138) - there is more about that in this document.

This publication is intended for general guidance and represents our understanding of the relevant law and practice as at November 2026. Specific advice should be sought for specific cases. For more information see our terms & conditions.