Solar Media Market Research analyst Josh Cornes looks back at solar progress in Britain by 2025, noting that despite this being the best year ever for deployment, there is a lack of projects due to grid connection until 2030 following the National Energy System Operator’s grid connection reform.
UK Solar was booming in 2025, with record numbers of submissions and approvals, projects being completed at a pace not seen since 2015, and construction of projects worth more than 4 GWp underway.
Clean Power 2030 generated a lot of activity, with deadlines set by the National Energy System Operator (NESO) for applications due before 20 years.e It will be granted protected status in December 2024, ahead of reforms to the way it handles grid connection applications. This resulted in more than 30 applications, for a total of 2.5 GWp, reaching the planning portals in December 2024. This influx made the fourth quarter of 2024 the busiest quarter for submissions ever to date.
The next deadline for submissions was originally set for the end of July 2025; However, delays caused by the application portal postponed this deadline by four weeks.
It’s no coincidence that the second quarter of 2025 overtook the fourth quarter of 2024 as the largest quarter in terms of submissions. According to Utility-Scale Solar: UK Pipeline Database from Solar Media Market ResearchQ2 2025 reached more than 5.6 GWp. More than 2.2 GWp of this came in June alone. The third quarter was also extremely productive, with 4.2 GWp of submissions, more than half of which in July alone.
It’s no surprise that once the application deadline was reached, the market went quiet. In the fourth quarter of 2025, barely more than 1GWp was submitted, including two Nationally Significant Infrastructure Projects (NSIPS); this lull led to one of the slowest quarters ever in terms of submissions.
Although total capacity for entries was significantly greater than any year before, volume was down, the lowest in the past five years. While 2021-2023 all had over 250 entries, 2025 didn’t even reach 200.
This is explained by the enormous shift towards large-scale solar energy, with the average project size being planned now exceeding 80 MWp. In the past twelve months, 17 projects of more than 100 MWp have been submitted to the Planning Inspectorate (PINS) or the Energy Consents Unit (ECU). Even at local planning authority (LPA) level, around half of the submitted capacity was exports of 49.9 MW, the highest capacity that a local planning authority could have approved.
Figure 1 highlights the rebound in the fourth quarter of 2024 and the second and third quarters of 2025. We can also see the big difference in the first and fourth quarters of 2025 compared to the previous years, which were previously the most active quarters.
Figure 1: Annual solar applications and decisions, identifying the massive activity in the market, with both reaching record highs. The first and fourth quarters of 2025 were extremely quiet, with the fourth quarter seeing one of the lowest numbers of submissions ever.
In Figure 1 we can also see that decisions skyrocketed: more than 11.5 GWp was decided in 2025, an increase of 29% year-on-year (year-on-year). Although this is positive at first glance, only 9.1GWp of this has been approved; the remaining 2.4GWp was rejected.
Opposition to solar projects and renewables in general has grown, with the voices opposing each project seeming to be louder than those supporting the project. This has led to a 25% refusal rate at LPA level, most of which then appeal, 90% of which are subsequently approved, wasting almost a year’s worth of work to get to the same stage some get to in three months.
Implications of grid connection queuing reform
The topic on everyone’s mind right now is: With this significant pipeline and activity in the market, why is there still a 7 GW shortfall for Gate 2 Phase 1 projects?
Projects that are not yet advanced have received Gate 2 Phase 1 offers, while Ready to Build (RTB) projects have received Phase 2 offers. There is a clear lack of progress as there appears to be no project with an original grid connection date after 2030, brought forward to before 2030, after the reform.
Progress was something many developers were counting on, with some selling off projects to reduce their portfolio in the expectation that their grid connection date would be brought forward in the queuing reform. Other developers were willing to take risks and purchase projects without confirmed Gate 2 Phase 1 connections. The uncertainty and activity led to a flourish in the mergers and acquisitions marketwith some developers purchasing up to 10 projects from different developers. Others have changed their business models: where previously they wanted to build, own and operate projects, they now sell their RTB portfolios.
A webinar organized by Solar energy portal on January 19 will delve deeper into the results, looking at the implications of NESO’s grid connection queue reform for UK solar and energy storage developers. More information And sign up for the free webinar.
All the data above comes from Solar Media Market Research analysis, which can be accessedhere.
Send an email to book a demo and access the data[email protected].
