Well the article is specific about replacing gas boilers with heat pumps, of course where the boiler is already electric there is not this issue (or it is margi

Well the article is specific about replacing gas boilers with heat pumps, of course where the boiler is already electric there is not this issue (or it is marginal). BTW AFAIK those thermosolar thingies used in Israel are quite good but they - at least the ones I am familiar with, common in Tunisia also - have anyway a supplemental electric resistance and are anyway only suited to self standing homes or very small condo's that have a flat (terrace) roof. And anyway in the same hypothetical 24 flat condo, 6 floors by 4 flats, you would need 48 pipes + 24 electric ducts going to the roof, but most lower floors flats (first, second or third floor, maybe also fourth) would be too far away so you would need a third pipe (24 of them) for circulating the hot water, and of course 24 pumps. And of course the climate in Israel or Tunisia can be compared to only some extremely southern regions of Italy and Spain.