Project to test potential for geothermal energy

Phil Castle, The Business Times

John McLennan

Heat in the ground offers a widespread source of energy that could be used to generate electricity, according to a scientist involved in a research project in Utah.

“There are challenges. But there are real opportunities here,” said John McLennan, an associate professor of chemical engineering at the Energy & Geoscience Institute at the University of Utah.

McLennan led a presentation hosted by the Grand Junction Chamber of Commerce on geothermal energy and the Frontier Observatory for Research in Geothermal Energy (FORGE) near Milford in central Utah.

Geothermal energy — heat generated and stored in the ground — long has been used as a resource, McLennan said. In Western Colorado, geothermal energy is used not only in hot springs and spas, but also to heat greenhouses and even an alligator park. Colorado Mesa University in Grand Junction constitutes a “poster child,” he said, in using a system of underground pipes to heat and cool buildings and save $1 million a year in utility costs.

Geothermal energy also can be used to generate electricity in heating water that’s turned to steam to spin turbines, McLennan said. Traditional geothermal plants require a combination of sufficient hot water at shallow depths. But technology has advanced that could take advantage of the heat that’s more prevalent at deeper depths, he said.

FORGE will test different techniques and technologies for developing geothermal resources, he said.

The Department of Energy will provide up to $140 million to the University of Utah over the next five years to fund research at the site.

The location is a good one, McLennan said, not only because of the geothermal resources found there, but also the absence of endangered species, drinking water supplies or human activity. There’s also a lower risk of inducing the earthquakes sometimes associated with injecting water underground.

Wells will be drilled to various depths at the site. Horizontal drilling and hydraulic fracturing also will be used to fracture the rock between wells, he said. The plan is to inject water down one well, have it pass through the rock and heat up in the process, then go back up another well.

McLennan said the heat in the ground also will test drilling and fracturing techniques and tools.

McLennan said he’s hopeful research at FORGE will help in developing large-scale, economically sustainable heat exchange systems.

There’s a possibility the techniques could be used with abandoned oil wells, he said.

Geothermal energy doesn’t yet promise to play a major role in electrical generation in the United States, but could play a bigger role, McLennan said. “It’s a small part, but it’s a potentially growing part of the energy sector.”

For more information about the Frontier Observatory for Research in Geothermal Energy, visit www.energy.gov/eere/forge/forge-home.