Tech Outlook: NM Tech’s Shari Kelley explains geothermal energy

This week, Shari Kelley was the guest on the Tech Outlook podcast, talking about the potential of geothermal energy in the state.

Kelley is a geophysicist and field geologist at the New Mexico Bureau of Geology and Mineral Resources and the New Mexico Institute of Mining and Technology.

She talked about how New Mexico can take advantage of the Earth’s natural heat as a resource to heat or cool buildings or even generate electricity. It’s a tool she thinks can help New Mexico in its renewable energy transition.

Being a geophysicist and a field geologist, what do your typical days look like?

“Because I have a variety of jobs, every day is a little bit different. As I do field geology, I get up and go out and make geologic maps, which is awesome.

When I’m in the office, I do a variety of things, but recently, I’ve been doing a lot of work on geothermal research because we got some funding from the state Legislature about a year ago, and we are lucky enough to have continued funding for the next three years. And so we’re starting to really set up a research center at New Mexico Tech and within the Bureau of Geology.

And this past year, we’ve been working on updating our geothermal database. We’ve been talking to New Mexico State University about a geothermal system that they had in place down there to see if there was any chance of getting it going again, and then organizing workshops designed to connect people at universities, national labs, legislators, policymakers, regulators and the geothermal industry so that we can really get geothermal off the ground here in New Mexico.”

What exactly is geothermal energy and how does it work?

“It’s based on heat coming out of the Earth.

The heat within the Earth comes from two sources, (and) one is related to the formation of the planet billions of years ago. And then up in the shallow part of the Earth’s crust, there are common rock-forming minerals and common rocks that have uranium, thorium and potassium in them — those elements are radioactive, and when they decay, they generate heat. And that’s the main thing that keeps the Earth’s heat engine going.

So there are places around the Earth where there are shallow heat sources that are related to active tectonics, vaulting and that kind of thing, or active volcanism. And in those places you don’t have to drill as deep to get to the temperatures that you would like for economic development of geothermal resources…

We can use that heat to heat and cool buildings, heat greenhouses, raise fish or make electricity, if the temperatures are high enough. There’s a spectrum of Earth’s heat that can be utilized.”

Why do you think it’s helpful or even necessary to utilize geothermal energy in today’s climate?

“An overarching goal is to try to reduce C02 emissions, and here in the state of New Mexico, there’s an Energy Transition Act … that really wants us to shift from fossil fuels to renewable resources by 2045.

And so there are a number of different carbon-emitting sectors within our country. One of them is our residential — residential is about 19% of our C02 emissions. And so if you could use Earth’s heat to heat and cool buildings, that would reduce our footprint quite a lot. Another, of course, is transportation, and so if we can figure out a way to use geothermal energy to generate electricity, we can help that transition to electric vehicles.”

What works well with geothermal energy here in New Mexico and what are some challenges that the state is still facing?

“So we have a geologic feature that bisects the state that’s called the Rio Grande rift, which allows Earth’s heat to come closer to the surface. And there are several manifestations of it at the surface in the form of hot springs at Truth or Consequences and Ojo Caliente and other places like that. So we know we have good resources here. And it’s geologically controlled, and we understand that the geologic processes that are controlling the location of the resources.

There’s a couple of challenges. Some of our geologic basins are very well-studied. There’s lots of data. There’s lots of wells. There’s lots of geophysical information that we can use to help us find resources. But there are parts of the state, particularly the Zia Basin, and well, most of the basin south of the Albuquerque basin — really, that amount of data that is available to help us pinpoint resources is not available.

So doing some more geophysical surveys would be helpful for helping us locate what are called ‘blind resources’ — things that don’t manifest themselves that they’re at the surface, but if you were to drill into them, you would be able to utilize the resource.

And another barrier, that is not New Mexico-centric, is permitting out on federal lands. And right now, Sen. (Martin) Heinrich is working with a group of other senators at the federal level to make permitting on BLM land for geothermal more on an equal footing with permitting oil and gas wells on BLM land. So it’s a barrier now, but people are aware of it, and we’re starting to get, hopefully, some resolution.”