While they can have these elements, heat-pumps in general have come a long way in their ability to get heat out of the air at cold temperatures. Mine is still o

While they can have these elements, heat-pumps in general have come a long way in their ability to get heat out of the air at cold temperatures. Mine is still over 160% efficient at -13F, with no loss of capacity. Below that it'll still operate at over 100% efficiency, but capacity starts to drop, so some part of the heating load may need to be made up by other means (it's common to install a handful of cheap resistive heaters for that case, as they add a redundant system that can continue to work even if the heat pump is out of service). > So heat pumps will lower overall energy usage, but not peak usage. This would only be true if we go far beyond normal 'cold climate' temperatures for a long period of time.