Ofgem is investigating June.
Your bill already paid for it.
On 17 July Ofgem ordered a formal review of how the grid operator handled the heatwave week of 22 June. The lights stayed on. The cost of keeping them on is the part nobody has been asked about.
🌡️ What actually happened
On 23 June, at 7pm, grid frequency dropped to 49.685Hz. Normal is 50. That is not a blackout. It is the grid equivalent of a wobble you feel in your stomach.
Two Electricity Margin Notices followed, on 24 and 26 June. That is the operator saying out loud that the evening peak looks tight.
On 24 June NESO paid up to £1,400 a megawatt hour for about 1.7GW of imports. Nearly twenty times the average price the same month a year earlier. Gas plants had cut 2.5GW of output because they run worse in heat.
📋 What Ofgem has asked for
Two things. A regulatory review of the system stress that week. And a separate independent investigation, run by a law firm, into whistleblower claims about control room decisions and record keeping.
Ofgem says the system operated reliably and no customer lost supply. Both statements are true. Neither answers the question of what it cost.
🏠 Why you should care
Every pound paid at £1,400 a megawatt hour ends up in the balancing charges on your bill. About £50 of a typical annual electricity bill already goes on balancing the system.
A hot, still evening is now the hardest day the grid faces. Not a cold one. Summer used to be the easy season. It is not any more.
The cheapest fix on the list is the one already in your house: using a bit less between 5pm and 8pm when the operator asks. It costs nothing to build. It just needs people connected.
Ofgem will spend months on this. The finding will be that the system held. The lesson is that it held expensively, and the cheap alternative was sitting in millions of kitchens doing nothing.