[alancalverd]

I was looking at the graph you posted. Sort of exponential, so not a lot before 1960. I'm sure I  remember Cambridge being "converted" in 1966, but anyway the fact that 20,000,000 appliances were done long before the internet existed surely suggests that we could do twice as many in the Brave New World of Massive Data, particularly if the alternative is to freeze or expend huge quantities of CO2 to make heat pumps.

And my wonderful heat pump has just died again. Could be the control board, maybe a software glitch, pump speed monitor, whatever....may take a week to diagnose, then wait until the semiconductor industry deigns to supply an obsolete part (it's nearly a year old)....Never had a problem with gas or oil boilers that couldn't be fixed in an hour by a bloke with a spanner.
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