Presidio Municipal Development District votes to fund geothermal energy feasibility study 

PRESIDIO — Last week, the Presidio Municipal Development District (PMDD) voted to allocate $15,000 for a feasibility study for a potential geothermal energy plant in South Presidio County. Though it remains to be seen whether that study will lead to a full-fledged drilling operation in Presidio, the vote marked significant interest from district leaders in bringing the technology to the region.

Trey Gerfers — who serves in several leadership roles in the county, including as general manager of the Presidio County Underground Water Conservation District — first brought the proposal to the Presidio County Commissioners Court in June, and was present at last week’s PMDD meeting to champion the idea before the economic development group (Gerfers also penned a column in this week’s Big Bend Sentinel on the merits of harnessing geothermal energy). Gerfers said he believes the technology would be a boon to the local economy and would provide a self-sustaining energy source.

“The benefits could be having energy infrastructure that the county could tax, that could be a good revenue source, jobs, cheap electricity, and more business opportunities, more development opportunities,” said Gerfers to board members.

“Imagine the statewide grid failure — that wouldn’t affect us,” he continued. “We’d have our own electricity source.”

Researchers at the University of Texas at Austin’s Bureau of Economic Geology will use PMDD’s $15,000 to conduct the study led by Dr. Ken Wisian, who attended last week’s meeting remotely to give a presentation about the potential benefits of bringing geothermal energy production to Presidio. Wisian is a lead author on a report called The Future of Geothermal in Texas: The Coming Century of Growth & Prosperity in the Lone Star State. 

The report explains that geothermal energy production harnesses heat under the earth’s surface to generate electricity. The earth’s core is as hot as the temperature of the sun — drilling just a few kilometers into the ground can yield water hot enough to produce electricity. 

In a geothermal plant, hot water is pumped from below the ground to the surface, where it becomes steam. The steam spins a turbine connected to a generator that produces electricity. Once the steam has passed through the turbine, it is funneled into a cooling tower that helps it condense into water once again — so that the cycle can begin again. 

In comparison to other forms of sustainable energy, geothermal energy has a much higher “capacity factor,” meaning the percentage of the time a plant is producing energy while it’s operating. Geothermal energy has about double the capacity factor of wind energy and quadruple the amount of solar energy. 

Wisian and his co-authors are firm believers in the technology. “The amount of heat energy beneath our feet is estimated to be many thousands of times larger than what we would need to power not only Texas, but the world,” the report reads. 

Though Wisian had also presented before the Presidio County Commissioners Court, he decided to also approach PMDD because he felt the area had the best potential for the project. “We will survey the whole county, but the reconnaissance I’ve done already strongly shows that the heat gets a lot better the closer you go to the river,” he said. 

He described a number of perks to installing the infrastructure: many Texans are nervous about the future of the state’s energy grid as record temps tax a system that left thousands without power during a winter storm in 2021. The City of Presidio could supply its own power — and have plenty to spare. 

City Administrator Pablo Rodriguez was excited about introducing another industry to the area — one that could potentially be the first of its kind in Texas. “Our friends to the north in the Permian Basin have oil underneath their feet,” he said. “We do have a solar plant here, but other than that we don’t offer a lot as far as producing electricity.” 

Wisian explained that a potential difficulty in scouting South Presidio County for geothermal power is that the area’s wells are relatively shallow. However, geothermal energy could potentially be harnessed at 6.5 kilometers — a standard measurement for the depth of oil and gas wells. 

PMDD ultimately decided to commit $15,000 toward a feasibility study to help determine if Presidio County is ripe for a geothermal plant. Wisian cautioned that the study was an important first step, but wasn’t a promise of things to come. Ultimately, if the study results are positive and Presidio elects to move forward with a prospective project, it will have to issue a request for proposals seeking companies interested in bringing the technology to the city. 

The new frontier of energy technology currently fuels just 0.5% of the country’s power grid, explained Wisian. “It’s a necessary step,” he said of the survey. “But it doesn’t guarantee that someone’s going to dance with you.”

Board Member Liz Rohana was still excited about the potential for Presidio County to be on the cutting edge in sustainable energy. “I feel like we have to take a chance to make something bigger-scale happen here,” she said. “I do look at this as an opportunity in so many ways.”