A friend of ours pumps water from the bottom of the Chattahoochee River into the marble floors of his house in the summer for cooling. In winter they have a diversion valve that recorculates the water to solar collectors that heat his indoor swimming pool. It’s nice to be rich. Warm floors in the winter. Cool floors in the summer.
I don’t have the cool floor thing, but my house is all infloor radiant heat. Wood fired, propane back-up.