I really don't see much difference between EGS and what we are doing. Both methods use hot rock to raise the temperature of water. With EGS you pump the water in through an injection well then extract it through a production well. What we do is the same, except that the water already is hot and available under groud. Once extracted by a production well it is injected by an injection well. The only difference is where the water comes from.
EGS however negates the need to find hot water geothermal formations and just look for hot geological formations.
I am not trying to dis-persuade your interests in EGS. Nicola Tesla proposed this in the 1920's. - He pointed out that there was no energy problem, all you had to do was drill a deep enough hole, virtually anywhere, and you had an energy source. - He also mentioned that the technology to drill these holes inexpensively has yet to be developed. - For myself, Tesla is one of my inspirations I credit as becoming a geothermal investor. - As Tesla foresaw, even today, drilling these holes represents a tremendous investment for our small geothermal companies. - Some observations. - One) AltRock, I think that was their name, went bankrupt trying to go EGS. Were they working in Central California near the current ‘Geysers’ geothermal fields. Their illustrations of how this would work are very convincing. - Two) Very recently, in Germany, some EGS projects were underway. People started complaining that whey were noticing earthquakes. As a result EGS projects are now illegal in Germany. People can be very antsy about faking. - IMHO, I think that taping into existing underground superheated water systems is the easy way to go. Cherry picking. - The dry systems require larger investments and risks. - Someday we will see EGS. If I am still around, perhaps I will be driving a ‘atomic’ automobile that will run a for a hundred years on a D-Battery sized cannister. (LOL) - RJ