Do heat pumps and super insulation complement or compete with each other?
After reading the article on “how much insulation is too much”, I found Marc Rosenbaum’s stats on 11 cold climate house configurations interesting. He points out that the difference in energy savings is very small between a minimally insulated and poorly air sealed house and a super insulated and very tight air sealed house. This is because he starts with an 2.5 cop heat pump and a heat pump domestic water heater. He sets the miscellaneous loads (appliances and lighting) at 4800 kwh year. The domestic hot water at 1850 kwh year, and the only variable is space heat. The bad house uses 2156 kwh year the best house (super insulated) uses 774 kwh year. Only 1382 kwh difference!
So it seems it is uneconomical to super insulate when you have a heat pump. Or…it is uneconomical to have a heat pump if you super insulate. In other words these two strategies are not friends…they eat into each others return on investment. One must choose. Which is the best choice? In new build, I go for super insulation. In old build…heat pump. Am I right?
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