1979 was the year of peak coal fired power generation in the UK, at numerous huge coal power stations. My local one at Didcot had railway sidings and a half square mile dedicated to the coal heap. The furnaces of these were so big that they took too long to cool down and warm up, so uses for night time baseload had to be found. The Belgians put streetlights everywhere; even motorways in the middle of the countryside. Britain mobilised the storage heater sales reps, and pushed unsuspecting customers towards 'Economy 7'. All to use up night time electricity, from power stations too big to switch off.
Fast forward 40+ years, and most of the coal heaps have gone. Rows of jet engine sized combined cycle gas turbine generators need quite a few minutes to spin up, but not days. The requirement for night time storage heaters is (unofficial; only me saying this) long gone. Economy 7, same hours every night always cheap, is (unofficially) not really what is needed. If it is not really needed then the sales reps won't try at all to get the best deals for you.
"smart" meters on SMETS2 record and transmit 48 metering periods per day in half hour intervals. Optionally, customers with SMETS2 smart meters may select a utility bill provider whose 'agile' tariff bills a different price in half hour intervals. An example of that price, over the first week or so of September 2023 is pictured. Night time is not the only cheapest time because there was often a solar generation boost around mid-day. Hence Economy7 is no longer the best option to find cheaper electricity.
Last edited by wizzo227; 20-09-23 at 15:41.