Heat pumps only work on their own in mild climates. Cold climates still require furnace in conjunction with the heat pump. Good luck convincing anyone in the northern United States of getting rid of their furnace or hot water heater. Spouting this sort of head-in-the-clouds, wrong information only weakens your cause.
“WHERE DO HEAT PUMPS WORK BEST?
Heat pumps are more common in milder climates, where the temperature does not typically drop below freezing. In colder regions, *they can also be combined with furnaces*for energy-efficient heating on all but the coldest days. When the temperature outside drops too low for the heat pump to operate effectively, the system will instead use the furnace to generate heat. This kind of system is often called a dual fuel system – it is very energy efficient and cost effective.”
Gas is still an inferior solution in those cases - wood pellets are better for those climates. Better yet, a combination of heat pumps and wood pellet furnaces gives you the best of both worlds - very energy-efficient heating while the temperature is still not too far below freezing (iirc heat pumps still beat alternatives as far down as negative 10-15 C), and wood pellets to handle the most extreme colds of the year.
There's also the alternative of putting the outlet of the heat pump below ground, where the temperature never gets that far below zero.
It's entirely incorrect to say that heat pumps only work in mild climates. I live in a country where we do not have a mild climate, and heat pumps are becoming more popular each day, owing to their technological superiority.
“WHERE DO HEAT PUMPS WORK BEST? Heat pumps are more common in milder climates, where the temperature does not typically drop below freezing. In colder regions, *they can also be combined with furnaces*for energy-efficient heating on all but the coldest days. When the temperature outside drops too low for the heat pump to operate effectively, the system will instead use the furnace to generate heat. This kind of system is often called a dual fuel system – it is very energy efficient and cost effective.”
https://www.carrier.com/residential/en/us/products/heat-pump...