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25 States Agree To Quadruple Number Of Heat Pumps In America
(cleantechnica.com)
This is a most excellent place for technology news and articles.
Except when it's very cold outside, which is what was discussed here. Heat pumps are great (have one in my home), but it might not be ideal in very cold areas, especially if electricity prices are high compared to other energy sources.
You need to be in a very, VERY cold area for that to matter. While these places exists, I'm sure it's not the case for a lot of the states I've seen marked in that article. Heat pump can heat the inside of your house even when it's freezing outside.
...and it will never go below 100% because most have resistive heating as backup.