A conversation with Cary Smith: A founding innovator of networked geothermal

November 23, 2022

Cary Smith, owner of Sound Geothermal Corporation and a principal with the Grey Edge Group, has designed countless geothermal systems across the country. This fall, Cary visited HEET at Eversource’s worksite in Framingham, Massachusetts, where the first utility-run networked geothermal system is currently being installed. I (Carrie, HEET Director of Communications) had a chance to talk with Cary during a lull on site.

“How does it feel for you to see networked geothermal evolve over the years, to the point where it’s now being installed by a gas utility?” I asked. 

“How do I feel? I feel like my dream is coming true,” Cary said. “I'm excited about the utilities actually taking this up because, that way, it’ll get implemented at a much broader scale, faster. And that's what we need—proof of concept. I've got it. I'm convinced. But I’ve got 35 [networked geothermal] systems that I live with day-to-day.” 

Cary studied chemical engineering and always showed an interest in science. “Since I was a kid, I mean, I had probably the most elaborate chemistry set. I was always blowing something up or burning something,” Cary said. 

It was in college that he first came across geothermal energy and heat exchange. At the time, it seemed like magic. How could heat from the ground not only heat but cool a building? That magic technology turned out to be ground source heat pumps. 

Cary’s first jobs were in the oil and gas industry, where he learned resilient piping design techniques and innovated drilling process improvements. “That gave me an excellent background to sit down today and deal with utilities because I can speak their language,” Cary said. 

It also informed the highly efficient, low-cost networked geothermal systems that he went on to design in the early 2000’s. Two of our favorite projects Cary has designed are at Colorado Mesa State University and Weber State University in Utah. These systems have cut campus energy and water use, radically reduced emissions, and have run smoothly for over a decade. 

“At the time, all of the universities, schools and municipal buildings were looking for ways to save money. And they were looking for ways to go green because they were starting to get pressure from the students, faculty and alumni to pay attention to what was then called global warming,” Cary explained. 

At first, Colorado Mesa decided to convert just three buildings to a non-gas system: a student union, a classroom and a dorm. 

“I said, ‘This is perfect.’ And I explained to them [the university] that the students couldn't be in the dorms and the classroom at the same time, so we were going to have a diverse load. They listened and you could just see the light bulb come on. I said, ‘What I want to do is avoid any external heat being added to the system if I don't have to because that'll keep our carbon footprint down.’” 

“There were no incentives then that were applicable to the colleges or the municipalities. So, at Weber State for example, we had to do it strictly on savings. The energy savings from the geothermal system itself were kept and that built the next year’s thermal system. That is the way we've been progressing.” 

At Weber State, energy costs have been reduced by over 40% and direct greenhouse gas emissions reduced 31% since the baseline year of 2007. Colorado Mesa has saved $1 million/year on its energy bills and cut CO2 use by 7,881 metric tons. The college has grown to incorporate 17 buildings into its geothermal network, the equivalent of 12 city blocks. HEET has begun working with Colorado Mesa State University to help them share the outcomes of their innovative energy system in a data-based case study.

“It just amazes me how resilient these systems are. And we just can absolutely say the bigger the system gets, the more diverse it gets, the more versatile and easier to work. There is no reason why this can't be just like a water utility or just like a gas utility,” Cary said. “What I see here is a technology that can bind the renewable industry together, instead of us competing with each other. It's all a piece of the puzzle.” 

Which is exactly what HEET thought when we first met Cary and Garen Ewbank of the Grey Edge Group in early 2019. Discovering that they had designed and put in the ground nearly the technology we had proposed to gas utilities, a decade before, was the best gift ever. It was a critical piece of the puzzle, already completed, that allowed us all to leap forward. 

We do our best to acknowledge and thank Cary Smith and all the other founding innovators of geothermal networks—but that isn’t why he does this work, of course. 

“The reason I'm doing this is because I like it. I think it's challenging. It's a new frontier. And I'm right smack in the middle.”