To Gareth Harper,
2 questions for you: do you ever look up official data on anything; or do you come up with ideas in your head which are true because you say so, or because you want it to be true?
(in the same way that when Trump was asked for evidence he replied "I'm the evidence")
Here's the evidence proving that the figures in the letter are not "complete nonsense"
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/767027/Sub-national-electricity-and-gas-consumptio-summar-report-2017.pdfLook at table 1 and chart 1 and the relevant facts are there
https://www.gov.uk/government/statistics/regional-renewable-statisticsDownload Regional Statistics: Generation, look at 2012 and 2017 on the spreadsheet, the other data needed (hydro, Scotland) are there
Nobody can dispute this data because it's from the govt/BEIS and these people tell us that AGW is real and renewables are good. (I notice your data is from a renewables propaganda body)
The 100% claim was in The Times and it was noted down in 2012 by folks who actually understand electrical engineering, and the claim was probably made by a hydro trade body. The 2017 data was only released this month. I'm not surprised that you're not aware of it, but no doubt had you seen it you would have enthusiastically believed it without question or checking. The Times later removed it from the website; probably just house keeping, as editors don't understand engineering either.
You have my full permission to respond and say who was right and who was wrong.