In the latest installment of our occasional conversations with Tarrant County newsmakers, TCU geological sciences professor John Holbrook traces the path of geothermal energy from a niche research area to becoming the next economically viable source of clean energy.

Technology for harnessing heat from the earth’s core is developing at a rapid pace, and Holbrook has been an outspoken advocate for more investment in geothermal production, especially as Texas continues to face questions over its dependence on natural gas to produce electricity.

Holbrook is part of the research-driven Texas Geothermal Institute, which launched last month in an effort to provide oil and gas companies with a roadmap for the remaining technology gaps and potential funding opportunities in geothermal production.  

This conversation has been edited for length and clarity. For the unabridged version, please listen to the audio file attached to this article.

Samsel: Why don’t we start with how you came to TCU and how you began your research into geothermal energy? 

Holbrook: I’ve been a professor looking at sedimentary rocks for a very long time. Essentially what that makes me is a plumber. Lots of people need a good plumber, so I work heavily in the environmental industry with groundwater issues, and I also work with the petroleum industry. Geothermal involves the same problems, and is largely about moving water through the subsurface to harvest heat. I have one of many skill sets that it takes to make geothermal work. 

John Holbrook has taught in TCU’s geological sciences program since 2011. He is currently part of the Texas Geothermal Institute, a statewide consortium of researchers. (Courtesy TCU)

How did I get involved in it? It actually started a little over 10 years ago with the announcement of something called the SEES (Science, Engineering and Education for Sustainability) program that’s now run through the National Science Foundation. I always had a little interest in geothermal and pecked at it a bit, but this program was looking for people who had researched the next generation of sustainable energy and offered an opportunity. I said to myself: “Geothermal is a natural fit for this. This is sustainable energy coming from the earth. It’s something that we have plenty of. It’s one of those areas that, with a little bit of advancement, a little bit of attention, a little bit of love, could become an actual viable energy source.” 

I became the chief cook and bottle washer for something called SedHeat. I was the principal investigator for what’s called a research coordination network for the National Science Foundation, looking into how to bridge the challenges for producing geothermal energy from sedimentary rocks.

Samsel: What was the significance of the SedHeat initiative

Holbrook: It was getting people from engineering to geology to petroleum to business to education, to cyber infrastructure, and getting them in the same room and talk. The idea was to build a research community looking into this: How can you make geothermal energy from sedimentary basins economical? I ran that for about eight years. Since then, I’ve been working with new ventures and expanding out to other things. 

One of the things that was exciting about that was it was back in the days when we were really trying to understand whether this was viable, when we were really addressing the question of geothermal energy. It gives you the possibility to lay the foundation, and now that things have kind of taken off. It’s put a community in place from which things can now build. 

Samsel: How does geothermal work in terms of producing energy or putting any pollutants into the air? 

Holbrook: That’s the charm of geothermal – you’re not generating power. It’s like solar, you’re harvesting power, so that aspect of it’s gone. 

Second, if you do geothermal right, you’re doing it in closed loops where you never really introduce anything to the environment that wasn’t already there. We have the potential to be able to produce energy with extremely low surficial impact.

Most people don’t have a hard impression of geothermal, which means that it’s ours to win or lose.

John Holbrook, TCU geological sciences professor

We’re pumping water in one well, we’re pulling out another, you move the water over, you harvest the heat from it, and then you cool it or heat it or whatever you’re going to do with it, and you pump it back in the ground. There’s really no intrinsic need to ever pollute anything in that process. We can pump other fluids into the ground to harvest the heat, and one of our favorites we’re playing with is using Co2 (carbon dioxide), which means that we can actually be a net Co2 remover. 

Samsel: Do people perceive geothermal energy to be a clean energy source? 

Holbrook: I would say that one of the things that’s important about geothermal for us is most people don’t have a hard impression of geothermal, which means that it’s ours to win or lose. It’s not like oil and gas or nuclear where people have developed pretty strong opinions on it one way or another. Right now, we don’t have an active geothermal plant in Texas. That doesn’t mean we won’t – there’s a couple companies working on them right now, so it’s very important that we be successful at this and win the public over. 

Samsel: Where does the Texas Geothermal Institute fit into this picture? I know you and TCU have decided to become part of that research group. 

Holbrook: It’s somewhat like SedHeat, which I ran before, but it’s a next generation version of it. We’re actually looking at it from both research but also a development point of view. There are different companies that are looking at running geothermal and entrepreneurs who are interested in this. Then there’s a lot of people like us who are in the academic end who have that technical knowledge. We’re pulling together a lot of people who have, rather than just the science and engineering academic expertise, they have the technical expertise. The idea is to pull together an interface to pair the people who have been playing with the science and engineering of it with the people who are actually looking at producing electrons.

Samsel: You’ve talked about trying to encourage people to make the investments necessary to make geothermal energy viable. Where are we now, and what would it take to make geothermal more economically viable? 

We’re within pennies of what it costs to generate electricity with natural gas.

John Holbrook, TCU geological sciences professor

Holbrook: Let me take a step back to where we were. When we started out during the SedHeat project, geothermal energy looked like something that was a little expensive, it might be possible, but it wasn’t really catching on because there were a lot of challenges to actually making geothermal work.

But what we’ve seen over these last years is so many of the big challenges to making geothermal viable economically have started to collapse and cascade, and we’ve gotten several major advances in technology and understanding of geothermal systems that has shifted to where we’re now at the place where it’s tickling economic competitiveness for virtually all the energy sources. That’s why you’re seeing a certain takeoff now. 

The reality of it is that we’re at the place where it is on the cusp of economic viability. We’re within pennies of what it costs to generate electricity with natural gas. We need more people who will pull together the science and the ideas we’ve done, and invest and say: “Let’s give this a try.” 

There’s a saying that “we need a Mitchell.” Mitchell Oil was the one who said, “We’ve got horizontal drilling, we’ve got fracking, we’ve got the shales. What if we drill horizontal wells, fracture and generate the oil and get shale gas?” 

They had the guts to try it. It worked. It made money, and then everybody did it. That’s where geothermal is. 

You need those people who make those investments now at (the current) cost of technology that make it actually work and make it viable, and show everybody it can be viable and can be profitable. Right now, we’re sitting at that moment in geothermal.

Haley Samsel is the environmental reporter for the Fort Worth Report. Her position is supported by a grant from the Marilyn Brachman Hoffman FoundationContact her by email or via Twitter. At the Fort Worth Report, news decisions are made independently of our board members and financial supporters. Read more about our editorial independence policy here.

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Haley Samsel is the environmental reporter for the Fort Worth Report. You can reach them at Her coverage is made possible by a grant from the Marilyn Brachman Hoffman...

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