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Last time I looked in to it I’d still need a supplemental heater for when it’s too cold for the heat pump to be effective (there were a handful of weeks just this/last year where we would be in trouble) in Chicago.
Ground source makes a lot more sense for new construction where you’re already digging.
If you think all forms of agriculture aren’t heavily subsidized (at least in the US) then I’ve got a bridge to sell you.