National Grid is a naturally, and rightfully, cautious organisation. But as system operator, sometimes it takes it too far. I recall a couple of years ago attending its “winter outlook” meeting, and hearing the good news that we would meet the government’s “loss of load expectation” target. It was close, though. The SO’s response was to continue to procure additional backup supplies (the Supplementary Balancing Reserve, SBR) to increase the “headroom” above the target.