Greg brings more than 40 years in the HVAC&R industry and has made significant contributions to it through geothermal expertise, innovation, and mentorship. As Certified GeoExchange Designer (CGD) #3, he has led more than a thousand geothermal projects over 33 years. He holds four patents for advanced ground source technologies that improve geothermal system efficiency by enhancing heat transfer and energy recovery, wrote the geothermal heat pump chapter of the Encyclopedia of Energy Engineering and Technologies, and educates professionals through lectures and seminars, establishing himself as a leading authority in sustainable heating and cooling.

His expertise extends to central utility plants, solar thermal, waste heat recovery, decarbonization, energy audits and calibrated energy modeling, and forensic analysis of HVAC systems. Greg's most treasured work is the mentorship of more than 50 early-career mechanical engineers through the move from academia to professional practice with many now becoming industry leaders themselves.