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If I recall correctly, well water typically has a temp of around 62-67*f, so it would definitely help warm your pond.
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Funny that I never new that well water was different temps in different parts of the country. I just thought well water was the same as it was far enough underground that it all met equal conditions. But in the north well water is around 55 degrees, I hear in Florida it is closer to 70! I know this time of year when you brush your teeth with well water you can tell that it is getting colder than in the summer. In the winter the water heater has to work harder to bring it up to temperature. The colder well water in the north vs the south helps out the geothermal users who are trying to dump heat from the house to the outside, but doesn't help much when you are trying to extract heat from the water to make heat inside the house.
My brother does commercial HVAC, big chillers, and lots of heat pumps stuff. He told me that in order to help keep good ice skating conditions in our fickle MI winters I just need to put a closed loop out from house to the pond, then a small circulating pump with a small refrigeration compressor and I should easily be able to take the heat out. Sounds like a cool project to try except for the bill to excavate under the finished driveway and lawn!
We struggle in Dec as we have so much water heat and ground heat in the pond bottom and sides that we struggle to make safe ice. Usually we get wet snow and even during our cold snap in January with no snow to insulate I could see lots of spontaneous 'pores' form in the ice where ground heat was making its way up in the shallows.
WE had enough zero weather now that we can safely get quads or heavy garden tractor on the ice to assist in clearing the snow that has hammered us the last two days. Kids loving skating again, 2 snowdays in a row, probably a 3rd tomorrow due to bitter cold. Have to keep them from bare skin exposure in this weather and wind though.
