 Recent government mandates have seen the phase-out of R-22 refrigerant and its replacement with more environmentally sound R-410A refrigerant.While heat pumps with backup systems other than electrical resistance heating are often encouraged by electric utilities, air source heat pumps are a concern for winter-peaking utilities if electrical resistance heating is used as the supplemental or replacement heat source when the temperature drops below the point that the heat pump can meet all of the home's heat requirement.Even if there is a non-electric backup system, the fact that efficiencies of ASHPs decrease with outside temperatures is a concern to electric utilities.