I’m considering installing a geothermal heating system in a new build house and am trying to find a realistic Coefficient of Performance for a heat pump averaged out over the whole year. I have been quoted COP’s ranging from 4.8 to 5.6 but assume these to be the best achievable ratings. Has anyone information on the Seasonal Performance Factor for a heat pump for a house of 201 sq.m.
Also, what would be the best system to use in conjunction with the geothermal system for heating domestic hot water?