A GCHP system was patented in Switzerland in 1912, over a century ago. I was fortunate enough about 9 or 10 years ago to meet one of the pioneers of the industry in Burlington, ON...Mr. Bill Loosley. He installed a GCHP system in his home in 1950. The system used an existing oil furnace as an air handler to move heated air to the home and even had a desuperheater to produce domestic hot water.
For the first three years a diesel motor powered the belt-driven compressor. This was replaced with an electric motor, that still powered the compressor when I visited Mr. Loosley in about 2003 or 2004. The GHX is a direct expansion system where the compressor pumps refrigerant liquid directly through copper pipes buried in the yard behind the home. The system is not designed for cooling, but does provide a percentage of the domestic hot water with a desuperheater connected to the hot water storage tank.
In my blog I'll be expressing my opinions about what I've the learned about ground coupled heat pump (GCHP) systems over the last 30 years. I've been very fortunate to work with many interesting people who are passionate about this technology...engineers, geologists, mechanical contractors, drillers, excavation contractors...in different parts of the world. I've learned a lot from them and will be using this forum to pass on some of the things I've learned and feel are important. Please feel free to use this information if you feel it's worthwhile...hopefully you can avoid some of the same mistakes I've learned from.