According to a recent study by researchers from the Bureau of Economic Geology at the University of Texas at Austin, a common ingredient, salt, may play an important role in the transition to low-carbon energy sources. The research paper describes the potential of huge underground salt formations as hydrogen storage facilities, transferring heat to geothermal power plants and influencing carbon dioxide storage.
It highlights the role that industries with extensive experience in dealing with salt, such as solution extraction, salt extraction, oil and gas exploration, can play in supporting this transition.
"We see the potential to apply the knowledge and data gained from decades of research, hydrocarbon exploration and salt basin extraction to energy transition technologies," said lead author Oliver Duffy, a research scientist at the bureau. "Ultimately, a deeper understanding of how salt behaves will help us optimize designs, reduce risk, and improve the efficiency of a range of energy transition technologies."
STARR principal investigator Lorena MoscarDELLi (center) and postdoctoral researchers Ander Martinez-Doñate (left) and Nur Schuba (right) with core samples from the Permian Basin in West Texas. The team is evaluating emerging energy opportunities in the region involving hydrogen storage and carbon capture, utilization and storage.
The study was published in the journal Tektonika.
Salt has an influential role in shaping the earth's underground layers. It is easily squeezed by geological forces into complex and massive deposits, with some subsurface salt structures higher than Mount Everest. These structures and the geology around them offer many opportunities for energy development and emissions management, said Lorena Moscardelli, co-author of the study and director of the Texas Advanced Resource Recovery (STARR) program at the agency.
"Surface infrastructure, renewable energy potential, favorable subsurface conditions and a common positioning close to the market are key to planning underground hydrogen storage," she said. STARR is currently participating in emerging energy opportunities in West Texas involving the region's hydrogen and carbon capture, utilization and storage potential. "
The Salt Dome is a full-fledged hydrogen container used in refineries and the petrochemical industry. According to the document, these salt layers could also be used as containers for hydrogen needed for energy production. What's more, the porous rocks around them can serve as permanent storage points for carbon dioxide emissions. The study describes the potential benefits of producing hydrogen from natural gas (known as "blue hydrogen") and storing carbon dioxide. When hydrogen is sent to salt caverns, the carbon dioxide emissions from production can be transferred to surrounding rocks for permanent storage without being polluted by the atmosphere.
Large underground salt formations have the potential to help the energy transition in a number of ways. Salt deposits can host caves where hydrogen is stored (left) and can help direct geothermal power generation (right). Geology near the salt layer (middle left) is often well suited for permanent carbon storage, keeping emissions out of the atmosphere by moving them underground.
The researchers say the Texas Bay Area, which has many salt domes surrounded by porous sedimentary rocks, is particularly well-suited to this type of integrated production and storage.
The study also touches on how salt can help adopt next-generation geothermal technologies. Although the industry is still in its early stages, researchers have shown how it can harness salt's ability to easily conduct heat from warmer underlying rocks to produce geothermal power generation.
Commissioner Scott Tinker said that because salt has a role to play in developing new energy sources, it's important to thoroughly explore multiple avenues. He said the bureau's researchers are playing a key role in that regard.
"Researchers have been studying underground salt formations for decades. "Because of their role in hydrocarbon exploration, as part of the Strategic Petroleum Reserve, used to store natural gas, there is now potential to store hydrogen," he said. That's what makes researchers great. Constantly develop, improve, and find new applications. "