Project Aims to Improve Geothermal Drilling Bit Penetration
Texas A&M Project Ups ROP Using Plasma Bursts
A team of researchers from the J. Mike Walker '66 Department of Mechanical Engineering at Texas A&M University is developing a process to cut time and expense on geothermal jobs that involve hard rock such as granite. Shockwave and Plasma Accelerated Rock Cracking (SPARC) drilling technology, a U.S. Department of Energy funded project, aims to make geothermal energy a more viable alternative to fossil fuels.
“The drilling technology that we are working on has the potential to increase drilling rates (rate of penetration) and reduce the wear and tear of traditional drill bits,” says Dion Antao, assistant professor, part of the SPARC team. “This is achieved by locally prestressing or precracking the rock being drilled prior to the cutting action of the drill bit.”
David Staack leads the SPARC project. Stack is associate professor, Sallie and Don Davis ’61 Career Development Professor, and College of Engineering director of laboratory instruction at Texas A&M University. Filling out Staack’s team are Antao, Alan Palazzolo, who is James J. Cain Professor I, and Bruce Tai, assistant professor.
Staack says the SPARC technology will equip traditional drill bits with high voltage electrodes on the tip that emit a microscopic plasma discharge. The discharge shocks the rock and cracks it like a tiny explosion. Creating fractures and weakening the rock allows the drill head, affixed with conventional diamond cutters, to have an easier time breaking through the material.
Palazzolo adds that, along with setting the stage for further development of geothermal energy, using electric plasma bursts to increase the rate of penetration enables drilling to be streamlined and, therefore, more cost competitive with non-renewable resources.
“It’s very exciting to be able to apply my expertise in machining research to study rock drilling with a real-world application,” says Tai. “This is truly a novel, interdisciplinary idea that will be a game changer.”
In a separate release, Energy Secretary Rick Perry praised the project.
“Geothermal energy is a clean and efficient base-load energy resource, making it an important part of our nation’s diverse energy portfolio,” he says. “Developing new, efficient drilling technologies will reduce these costs and increase the availability of this domestic renewable energy resource.”
The DOE added that the SPARC system was capable of doubling rate of penetration for geothermal wells.
The SPARC project was among seven grants announced in late 2018. Other recipients included Argonne National Laboratory in Argonne, Illinois; Oklahoma State University in Stillwater, Oklahoma; Sandia National Laboratories in Albuquerque, New Mexico; among others.