Depends on how you heat. If you live in a climate where you need to heat in the winter and cool in the summer, ground source heat pump are cheaper to operate t

Depends on how you heat. If you live in a climate where you need to heat in the winter and cool in the summer, ground source heat pump are cheaper to operate than oil, gas and A/C. Solar will contribute to reducing your A/C electricity bills and also all the other power you use year-long, so they work together. If you live in a climate where you occasionally turn on an electric heater for those really cold days, this will only help during cooling season, while solar will contribute all year long.