From £1m to £7m: how solar made the grid so much more expensive to balance on hot days.

You'd expect lots of summer PV to make sunny days easy for the grid. Instead, balancing them costs seven times more than it did in 2017 — and consumers pay £1.60 for every £1 of solar wholesale value.

This piece started as a Bank Holiday LinkedIn post about 24 May 2026’s record-low Sunday demand and the 5× gas ramp that followed it. The response — lots of messages, comments, and “is this normal?” — convinced me it was worth pulling out the dataset and seeing how the heatwave gas ramp evolved year-on-year.