Minnesota is in the midst of a transition to sustainable, clean energies for the 21st century. One of those energy sources is hidden underground. That’s right—there are abundant geothermal resources below our state’s lovely surface. This is the conclusion of a report recently published by the Natural Resources Research Institute (NRRI) at the University of Minnesota, Duluth.
The NRRI research team and their state partners looked into the earth through 900 mining holes and wells to measure the heat gradient in rocks below Minnesota. They found no new fossil fuels, but they revealed an exciting amount of heat from geothermal sources. In a non-polluting, closed-loop technology, these thermal resources could be drilled with current natural gas technologies to a depth of 20,000 ft where the temperature is about 250 F. This heat is provided by the earth’s core, some 4,000 miles deeper.
The NRRI team was excited by this clean energy resource and its extent. “The potential is three or four times greater than we assumed,” stated Don Fosnacht, the project’s principal investigator.
The research team assumes that both federal and state energy policies would develop a process for harnessing this available and clean energy by working with utilities and investors. Utilities could use the heat from these 20,000-foot-deep wells to boil organic fluids whose captured exhaust would turn multiple turbines. This technology already exists and operates successfully, so there’s no need to wait for further technological advancements.
In an earlier study by MIT of geothermal resources in the U.S., they argued that a $1 billion investment could produce as much electricity as the equivalent of all 104 commercial, nuclear reactors operating today. After the infrastructure is built, the energy is very inexpensive.
Fosnacht emphasizes the elegant simplicity of this approach: “We need to harness the natural loss of heat from the earth’s core.” This type of technology offers a clean and local supply of energy that could be built in Minnesota by larger utilities to serve the state’s population—that’s good news for Minnesotans and energy entrepreneurs.
Resources:
Click here to see the report from NRRI >>
Click here to see maps and other resources >>
