House cooling idea using groundwater from this /. article from a guy in central Alberta:
Ok, so it hasn’t been unseasonably warm yet but this weekend it’s forecasted to be fairly toasty. I have an acreage with my own well. Having recently replaced the old oil burning furnace with a high-efficiency nat.gas furnace, I had the HVAC guy install a chiller coil in the plenum for an extra $150. The water I pull out of my 10gpm well comes out at 8C so I plumbed the well water through the chiller coil in my furnace (after removing the orifice), and hooked a solenoid up to the furnace so when the thermostat calls for cooling, well water runs through the chiller coil and blows cool air through the house. The output goes to a sprinkler on the roof of the house which further cools the house. The output of the eaves runs to a drip irrigation setup which irrigates the plants and garden... Eventually, the water ends up back in the ground. Along with some awnings in front of the SW view windows, the house stays fairly cool for the price of pulling the water out of the ground (and with a variable frequency drive well pump controller, it’s also fairly economical). It’s possibly more economical to run an actual compressor with refrigerant for shorter duty cycles. Not sure.