"If energy generators are not progressing their project, they will have to either move backwards in the queue or leave, making space for other projects ready to progress and connect," National Grid ESO announced.

The step is part of a targeted reform for how new grid connections are allocated, it added.

"These reforms will mean that projects will be able to connect up to ten years earlier," National Grid ESO said.

There are around 220 projects due to connect to the national transmission system before 2026, totalling circa 40 gigawatts (GW) of capacity, more than double current British peak demand in the summer months, the company said.

However, only half of these have got planning consent and some projects had moved their connection dates back by over 14 years, it added.

The grid operator had written to those seeking a grid connection asking for updates on progress and project milestones, to help identify non-viable projects, according to the statement.

(Reporting by Nora Buli)