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Oxford study proves heat pumps triumph over fossil fuels in the cold
(www.nationalobserver.com)
This is a most excellent place for technology news and articles.
Really? Where in the US or Canada do tens of millions if people live with AVERAGE winter lows of -25F?
Fairbanks AK seems to be widely regarded as the coldest US city, and that is -15F average lows. If I move to Prudhoe Bay on the northern coast of Alaska, then in find the -25F low I’m looking for. 
A quick search suggests Winnipeg is the coldest major city in Canada, and it doesn’t quite reach -20F average. There are of course some more remote towns that get colder; Canada goes pretty far north.