Anyone know anything about it good or bad?

I only know what I have read. It is much more expensive to install than more conventional methods. However, over time the system can supposedly pay for itself in reduced heating and cooling costs. Pipes are run underground (usually under the foundation of a building). THey are filled with water and connect to a unit in the basement. Since the underground temperature stays at around 55-56 degrees, the unit does not have the huge ranges in temperatures to heat or cool in a climate such as ours. It is best installed with new construction and may not be feasible as a replacement system. I am sure you can find lots of information on the internet.

Look up geothermal heat pump. I think a few folks in the Hagerstown area have them, so someone around here installs them.