In the desert of rural Utah, Utah FORGE is working on a project that could lead to a nearly unlimited supply of clean, renewable, and affordable energy.
Most of the world does not live near naturally occurring fractures and fault lines, making geothermal energy hard to come by—but FORGE hopes to change that. Funded by a $220 million grant from the US Department of Energy, FORGE has developed a field laboratory in Milford with enhanced geothermal systems (EGS). This technology enables geothermal power plants to be built anywhere in the world.
Conventional geothermal systems rely on the hot rock located near fractures and faults in the earth’s crust. Geothermal power plants drill a well that intersects with the natural fault or fracture, bringing hot water and steam to the surface and creating a clean, inexhaustible energy source. Creating an EGS involves drilling two very deep wells into the earth’s crust, where water is pumped down the first well and heated by the rock inside before returning to the geothermal power plant through the second well.
“The drilling of wells is being integrated with new technologies and techniques,” says Dr. Joseph Moore, primary investigator of the Utah FORGE project. “In 2021, we drilled our first deep, highly deviated well—the injection well. We also drilled a seismic monitoring well and a research well. We expect the second well—the production well—to be drilled sometime in late 2022 or 2023. Once the two wells are drilled, a series of circulation tests and additional research will be conducted.”
Dr. Moore has more than four decades of experience in geology and geothermal systems research. Though EGS projects have been conducted since the late 1970s, he says, the results of them have been modest, and no commercial-scale systems have yet been developed. “The Utah FORGE project is unique in that it is a laboratory dedicated to perfecting methods that will make EGS applicable anywhere in the world,” Dr. Moore says.
This project couldn’t be more timely, as the need for renewable, clean energy continues to rise. In 2020, clean, zero-emission energy sources generated roughly 21 percent of all the electricity in the United States. If we are to meet the goal set by President Joe Biden to achieve 100 percent clean energy in the US by 2035, clean energy has a long way to go.
According to a Department of Energy report, harnessing just 2 percent of the thermal energy at depths of approximately two to six miles would provide over 2,000 times the annual energy used in the United States.
“Utah has significant geothermal and EGS resources for heating, cooling, and electricity generation that are currently greatly underutilized,” Dr. Moore says. “But unlike solar or wind power, the public is not as knowledgeable about the use of geothermal energy and particularly the application of EGS.”
According to Dr. Moore, much of the available geothermal energy is not accessible with our current infrastructure. One megawatt can power roughly 400 to 900 homes per year for one year.
“The US has an installed capacity of approximately 3,700 megawatts of electricity from natural systems found mostly in California, Nevada, and Utah,” Moore says. “In 2019. the US Department of Energy set a goal of obtaining 60,000 megawatts of electricity from geothermal sources by 2050. Existing natural geothermal systems cannot meet that goal. In order to obtain the heat found beneath our feet, Enhanced Geothermal System technologies need to be perfected.”
One of the obstacles the Utah FORGE project has encountered while building EGS is the durability of tools. Most man-made tools are designed to endure temperatures found on the Earth’s surface, but this project works with temperatures far hotter than anything found there.
“We are working on new tools to develop permeability since we’ve discovered that many of the tools made for the oil and gas industry are failing at the high temperatures encountered at the Utah FORGE site—around 200 degrees Celsius or 400 degrees Fahrenheit,” Dr. Moore says. “However, we have realized many successes that bode well for the geothermal industry. Most significantly was the use of polycrystalline diamond composite (PDC) bits, which helped reduce the drilling time of the first deep deviated well by 40 percent.”
Developments in new drilling technologies are not only necessary for working with the temperatures inside the earth—but they could also help decrease the cost of building a geothermal power plant.
“Drilling accounts for half of the costs of a geothermal project,” Dr. Moore says. “As we continue to make breakthroughs in drilling, we expect the costs of entry to decrease very significantly. Utah FORGE has the potential to decrease drilling costs and reservoir creation even further than have already been realized.”