it’s cold but sunny, how can I help my heat pump?
I have to replace my furnace and AC soon since they are way past there lifetime.
I have a lot of sun where I live but
in the winter it gets cold down to 0F.
I am in climate zone 6.
now I have very well working solar water heaters and a phase change storage for that energy (all home made, it’s oversized for just warm water).
for an air source heat pump, is there any way I can use that warm water to get a higher COP so I don’t have crazy high electricity bills?
I was thinking of routing the supply lines through the water or adding a heat exchanger, though I haven’t found one yet for flanged connections.
another option for me would be to go with a ground source heat pump where I can use normal water to water heat exchangers (I don’t mind putting in the ground loop).
also maybe I can just add another evaporator coil with just the warm water? but I rather have the efficiency of the heat pump to at least double the kWh from the warm water.
For some data, during the day my solar collectors are rated for 10.2 kWh but produce between 2.2 and 6.8 kWh in the winter.
my thermal storage can store between 8.8 and 13.6 kWh, the latter with some PV help to get it above the water boiling temperature. the former is just the solar water.
so how can I help my future heat pump so that my electricity bill stays low?
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Replies
Interesting!
What makes you think your electricity bill will be high? How much fuel do you use for the furnace?
Something like an air-to-water heat pump could work well - you could run the water through the air handler from either the heat pump or the storage. That is the easiest and cheapest I think of the integrated options. I don’t know if it’ll make sense vs. just using an air to air pump and leaving the heat in the tank. You’d save like $25 (4kwh/day x 30 days x $.20/kwh) a month using the heat from the solar thermal, minus the DHW you use. It’s peanuts.
My first instinct is to say, do not mess with the heat pump at all.
Make sure that any solar hot water not needed for DHW is efficiently distributed to the house.
That way the heat pump is not running at all in those periods.