Following the conclusion of a Government Consultation last year, the capacity thresholds for Nationally Significant Infrastructure Projects (NSIPs) have been increased. Kate Drewett, Principal Environment Planner, describes the potential opportunities and difficulties this might bring for solar farm and onshore wind farm developers.

How has the NSIP threshold changed?

Following the Consultation response, the Government has confirmed that, in spring 2025, the capacity threshold for NSIPs increases to 100MW for solar farms and 100MW for onshore wind projects. This is lower for solar than the 150MW threshold expected.

Projects under the new threshold can still opt in to the NSIP regime via Section 35 of the Planning Act 2008, providing the Secretary of State is satisfied that the development meets certain criteria.

In Wales, projects with capacities under 50MW will now be processed via Planning and Environment Decisions Wales rather than the Welsh Government’s Developments of National Significance (DNS) process.

What will the impact of this change be?

Before the increase in thresholds, developers would often either limit proposals so not to trigger NSIP or scale up plans to make the cost of the process worthwhile. This proposal will enable more medium-sized projects to come forward under the Town and Country Planning Act (TCPA).

Overall, it is great to see growing Government support for these renewable energy projects. However, the question remains as to the support local planning authorities will get to help them with these larger scale projects. Although £100 million of funding support has been announced, it’s not yet been set out how this investment will help in practice.

Local planning authorities are already under pressure in terms of human resources, so the funding could be used to fill the gap. However, the right expertise may be restricted or unavailable in the areas where it’s required. This could further exasperate workload capacity and cause delays as more larger scale projects start to come through the system.

How can these hurdles be overcome?

Pre-application engagement with case officers and local authorities before submitting for full planning will be key. Working closely with local people and statutory consultees from the start of the process will help secure support for application and ensure items are addressed before going for planning. This doesn’t just make life easier for applicants, but for the case officer too.

Our team has existing relationships with various case officers and local authorities across the UK. This means we have knowledge of the personnel involved in each application, their ways of working and who’s able to provide pre-app services. We can then get in touch with the right people for upfront consultations and prioritise providing support and evidence in formats they prefer.

We can also make clients aware of potential project delays and offer realistic timescales. For example, many councils say they’ll give a pre-app response in 30-40 days, but our wide experience across the UK means we can advise whether it’ll realistically take longer. This means we can discuss the merits of this process with the client for each particular scheme and provide more accurate project timescales, making the process as smooth as possible for clients, even in the face of increased demand due to these threshold changes.

If you would like to discuss planning issues for any of the topics mentioned, please email kate.drewett@dalcourmaclaren.com