Tech Geothermal Project Bolstered By Department of Energy

UPDATE: November 12 -- Periodic status report updates on the drilling project, including depth and temperatures, are available on the web.

SOCORRO, N.M. November 5, 2009 – Looking to the west from Socorro in the evenings, many people are wondering about the bright spotlights illuminating the base of ‘M’ Mountain.

 
 The Rogers & Co. drilling rig at work in the shadow of 'M' Mountain. Photo courtesy of Dr. Mark Person.

The lights aren’t related to any explosives testing; a drilling company – under the watchful eye of a team of geologists – is working around the clock to find a source of geothermally heated water.

The federal Department of Energy awarded New Mexico Tech $457,000 earlier this year to drill a test well. Now, the agency has awarded Tech another $2 million to link the geothermal wells to the campus heating system. The project will drastically reduce the university’s reliance on its natural-gas powered heating system for campus buildings.

Vice President of Research Dr. Van Romero announced Thursday that the university received $1,999,900 from the Department of Energy through the federal stimulus package.

Tech President Dr. Daniel H. Lopez said the funding represents a significant boost to the university’s ability to be energy self-sufficient.

“This funding permits us to continue to develop alternative sources of energy to supply our campus needs,” Lopez said. “The ultimate goal is to produce enough geothermal energy to minimize our consumption of electric power and natural gas.”

Hydrology professor Dr. Mark Person is the principal investigator on the project. He is also developing a new graduate level course in Geothermal Resource Exploration, which has generated significant interest among graduate students.

The project will also serve as a hands-on teaching lab for students interested in learning more about geothermal energy, Romero said. The federal funding will also pay for two new graduate research assistants.

The campus hot water loop has suffered numerous failures in recent years, costing the university (and the state) millions in repairs. The state had provided funding to replace the system.

A diagram of the geothermal production well being drilled two miles west of campus.

In the meantime, drilling continues. As of Tuesday, Nov. 3, the Rogers & Co. drilling crew has nearly reached 300 feet, with water temperatures at about 37 degrees C. Ultimately, the primary pump will be set at that level – 300 feet below the surface, but the production well will be drilled to a depth of about 1,500 feet. The primary goal is to find water at 65 degrees C with a flow rate of 800 gallons per minute. Of course, if the geologists find hot water (90 degrees C) at shallower depths, they’ll stop drilling.

Based on previous geologic and hydrologic studies by Tech scientists Marshall Reiter and Peggy Barroll, the Tech team believes they’ve found a location where hot water is closest to the surface.

“We’ve known for a long time of the source of hot water under ‘M’ Mountain,” Romero said. “Thanks to the Department of Energy, we are able to tap into that heat source and put research into action.”

As ground water seeps into the earth on the San Agustin Plains surrounding Magdalena, the water descends as far as three kilometers below the surface – and heating up as it descends. Distinct geologic formations beneath ‘M’ Mountain push the heated water back toward the surface.

“We’re drilling on the bull’s eye of a heat flow anomaly at Woods Tunnel,” Person said. “It’s really exciting. A lot of faculty members are donating some of their time to this project because we believe in helping New Mexico Tech ‘go green.’ Plus, we can save the university – and the state – about $800,000 in cost every year.”

 

 
 The bottom inset shows the location of the geothermal well and the pipeline that will connect the well to campus. The top inset shows the location of hot water loop on the main campus. Graphics by Mark Person

The new federal appropriation will pay for the infrastructure (pipes, pumps and heat exchangers) to transport the hot water 2.1 miles from the base of the mountain to the heat exchanger at Facilities Management. University staff will install the pumps and an insulated pipeline, allowing the university to begin phasing out the existing natural gas heating plant. Engineering subcontractor Dan Hand will work with Facilities Management to design and oversee the installation of the district heating system. Jim Witcher, a geothermal consultant from Las Cruces is overseeing the well-site drilling operation.

Person said this phase of the project is exciting; the drilling will answer many questions about the potential for geothermal energy. At the current depth of 300 feet, the drillers have encountered fractured rock and the well is producing 1,000 gallons per minute. Person said the project’s success depends in large part on finding similarly fractured rock at deeper depths. Fractured rock allows heated water to easily flow to the well consistently over time.

“Fractured rock makes it hard to drill,” Person said. “But it’s what we want to see.”

Throughout the project, Department of Energy experts Dr. Douglas Blankenship in Albuquerque and Eric Hass of Golden, Colo., have been monitoring the project and offering advice. Person said the agency scientists and engineers have been extremely helpful.

Once the hot water reaches campus, the heat transfer unit will generate the energy required to heat all campus buildings. The spent water will then be injected back into a brackish aquifer. Person said the university will still need to secure the funding – hopefully from the state of New Mexico – to drill a 3,000 foot injection well. The hydrologists are taking special care to find a depth where the injected water will not effect the Socorro drinking water supplies. While still potable, the geothermal water has too high of a saline content to meet EPA standards for drinking water.

The federal Department of Energy is distributing $338 million in Recovery Act funding for the exploration and development of new geothermal fields and research into advanced geothermal technologies.

“The United States is blessed with vast geothermal energy resources, which hold enormous potential,” said Department of Energy Secretary Chu. “These investments in America's technological innovation will allow us to capture more of this clean, carbon free energy at a lower cost than ever before.”

These grants are directed towards identifying and developing new geothermal fields and reducing the upfront risk associated with geothermal development through innovative exploration and drilling projects and data development and collection. In addition, the grants will support the deployment and creative financing approaches for ground source heat pump demonstration projects across the country.

“We’ll be the only green campus in New Mexico,” Person said. “And only the second green campus in the nation. That makes this a very exciting project.”

– NMT –

By Thomas Guengerich/New Mexico Tech