There is a spreadsheet download available from the DOE. It compares different fuels and types of heaters that are commonly used in heating buildings. The user is able to enter their own local values to make a more valid personal comparison. The sheet is updated regularly with the national average costs.
Our primary residence is in the high mesa desert of NM. No ponds. The nearest water is about 1000+ feet straight down.
We'd do a closed loop in ground system. I've seen both vertical and horizontal systems installed here. We'd have to do a vertical most likely. This one had a series of vertically piped holes drilled in the front yard.