Ahead of revealing plans to reform the legal system surrounding Nationally Significant Infrastructure Projects (NSIPs), prime minister Keir Starmer teased the announcement on LinkedIn, with a post that simply read “I’m backing the builders. Not the blockers”.

It was a statement of intent reflected by not only the following day’s announcement that the number of legal challenges that can be launched against an NSIP would be reduced, but also in his pick for energy secretary, Ed Miliband, who went on a rapid-fire approval blitz of solar NSIPs mere days after taking office.

Few areas of the renewable energy sector appear to inspire such intense NIMBY-ism as solar energy and battery energy storage system (BESS) projects. Lengthy legal challenges and protracted planning processes can delay solar projects by years or even crush them outright, which poses a major threat to the UK’s 2030 net zero transition goals.

As such, the proposed reforms to the NSIP and legal systems are very much welcomed by many in the industry. Here, we examine some recent legal and planning challenges to proposed solar NSIPs that could have been avoided by a more efficient planning system.

The background and the need for reforms

Talk of reforming the NSIP process has been on the table for a number of months as the UK’s Clean Power 2030 deadline draws ever closer.

In October, leading planning barrister Lord Charles Banner KC issued guidance to the UK government on potential reforms to the NSIP system in order to provide a “roadmap” to speed delivery of major infrastructure projects – including solar developments.

This included the suggestion that the number of complaints objectors to NSIPs can make be reduced from three – first, in writing to the High Court, then at an oral permission hearing if permission is refused at a written stage, and finally before the court of appeal – to two, dropping the written objection stage. In announcing his intent to bring in such reforms, Starmer went a step further, adding that legal filings deemed by a judge to be “totally without merit” will be denied the right to appeal in a higher court.

The report notes that while only around 25% of decisions to grant a Development Consent Order (DCO) for a project are subject to judicial review—of which only four were overturned—the national importance of these projects means “delays resulting from unsuccessful challenges are a clear detriment to the public interest”.

Rasing NSIP thresholds to boost larger solar projects

One of the most significant changes to the NSIP regime is the long-planned raising of NSIP thresholds for solar projects from the current 50MW to 100MW. This came in response to the significant number of solar developments that choose to limit their size to 49.9MW – as high as possible without needing to cross into the NSIP system – owing to the high cost and extended process for NSIPs compared to local authority planning procedures.

In the last few months, Innova, RES, British Solar Renewables (BSR), Enso Energy, and Schroders Greencoat have made news with 40MW-49.9MW projects.

Solar Energy UK has noted that no UK solar developments have been proposed with a capacity between 50MW and 99.9MW, indicating that 100MW appears to be the limit at which developers view it worth entering the complexities of the NSIP system. However, in order to avoid a situation where 99.9MW becomes the new 49.9MW, the reforms to the NSIP system must ensure that the complexities of the system pose less of a barrier to developing larger projects.

Resolving disputes at the pre-application stage

One of the other significant proposed reforms is the incoming duty for all parties involved in the development of an NSIP to identify and narrow down areas of disagreement during the pre-application stage, lessening the burden on the planning system to deal with such complaints. As well as potentially solving disagreements on issues such as land rights before the proposals enter the system, this will allow the secretary of state to be presented with greater detail of unresolved issues at the time of application.

One recent example of where this could have cut months from an application’s approval process is the case of the recently approved 500MW Heckington Fen solar PV power plant under development by Ecotricity. The project was repeatedly delayed owing to ongoing disputes with landowners for the proposed site, the Crown Estate and the Duchy of Lancaster.

In August 2024, the developers requested an extension to the statutory deadline for providing information to the Department for Energy Security and Net Zero (DESNZ), but as the extension deadline of 27 September approached, Ecotricity again requested an extension, this time to 6 January 2025. While DESNZ did grant an extension to 24 January, it stated that it did so “reluctantly” and demanded that all the involved parties must provide evidence that an agreement had been reached ahead of the deadline.

While an agreement was reached and the development approved, it could be argued that the discussion of land rights should have been resolved long before the final weeks and months of the application process. A mandate to resolve such disputes, as is now being proposed by DESNZ, would have saved around five months to the approval time, as well as a not insignificant amount of departmental resources that could have been used to hasten the pace of other projects.