I have been wondering as I've explored our new houseboat and the docks: are there many houseboats with geothermal heat pump systems? It seems to me that it would be a good choice for marine use. Our lake water never got below 48 degrees all winter. A heat pump would work great at that temp. In summer, the water would always be cooler than the air. I know geo units are more expensive for home installation, but a large part of that cost is drilling the wells in the ground. Lastly, it would eliminate the bulky, noisy compressor unit that takes up space either on the roof or rear deck.

I am just curious. Do many of you or your neighbors have geothermal? Is there a big down side that I am missing?