Why Britain's gas plants are telling the grid less, later

I tested the obvious explanations for this autumn's shortage of gas in the South East. Age and overruns explain little. Running less, stopping and starting more and booking work days ahead explain a lot. And then there are the salmon.

After Britain's emergency call to France on Monday 12 October, the second in four days after the one on Friday 9 October, I wanted to know why so little of the South East's gas was there. The obvious explanations are the ones I started with. The plants are old. Their outages overrun. They run in shorter, less predictable bursts. Their owners book maintenance later. The weather gets in the way.

So I went through every outage notice published for a gas power station since mid-2017, every revision of each one, every availability plan generators have given the market since 2021, and the half-hourly output of every unit since 2019, to see which of those hold up.