Advice on setting balance points for hybrid heat pump/propane furnace
Sam2112
| Posted in General Questions on
Hi I’m trying to figure out how to maximize the economic efficiency of my new hybrid heating system. I want to set it to switchover to maximize energy savings.
EX heat pump runs down to 30 degrees, but when the outdoor temp is lower, it’s cheaper to burn propane, so the system switches over to propane.
For reference, I’m in Southern NH. Electricity is .22 a kwh and propane is $3 a gallon. My furnace is 95% efficient.
Does anyone know any good tools, formulas, or resources to use?
Thanks!
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Replies
A gallon of propane is 27 kWh of energy. At 95% efficiency and $3 a gallon that's $0.12/kHw. At an electricity price of $0.22/hWh the break-even point is a COP of 1.9.
If you go to NEEP.org and look up your heat pump in their database you can see at what temperature the COP is 1.9.
Thank you that is super helpful! Could you tell me how you calculated the break even COP? It would be helpfult for me to know when energy prices change.
The break even price is where the price of electricity divided by COP is equal to the price of propane. So 0.22/1.9=0.12.