The “Center for Coupled Chemo-Mechanics of Cementitious Composites for EGS” (C4M), located at the Brookhaven National Laboratory's Interdisciplinary Science Department, has been chosen as one of the 11 Energy Earthshot Research Centers (EERCs) as part of the U.S. Department of Energy's Energy Earthshots Initiative.
With this selection, the newly established research center is poised to receive $19 million in funding over the course of four years. This financial support will drive their efforts to delve into the chemical and mechanical properties of cement composites and other materials crucial in enhanced geothermal systems (EGS). The research conducted at C4M will play a pivotal role in designing environmentally friendly variants of cement composites, coatings, and other protective barriers intended to safeguard geothermal wells.
Geothermal energy, known for its reliability and around-the-clock availability, has the potential to harness vast underground heat reserves to generate gigawatts of electricity for households across the United States. However, geothermal projects face challenges, particularly in selecting cement composites that can endure extreme temperatures and corrosive geothermal fluids. Additionally, cement production is notorious for its significant carbon dioxide (CO2) emissions.
“To realize geothermal energy's potential, it is therefore essential to rationally design cost-effective, sustainable well-construction materials with a net-zero CO2 footprint,” emphasized Tatiana Pyatina, a materials scientist at Brookhaven Lab who leads the geothermal materials research effort and will direct the C4M EERC.
The C4M team will embark on testing novel cementitious composite materials to gain insights into the chemical transformations that occur under high temperatures and pressures. This research will inform the creation of robust and durable composites suitable for the demanding underground environments of geothermal wells. One of the primary objectives is to gain control over the solidification and transformations of these materials, making them suitable and cost-effective for well construction and operation.
“We hope that this research will enable us to develop net-zero CO2 materials that can reduce the cost of enhanced geothermal systems by 90% by 2035,” Pyatina added.
To address the CO2 emissions associated with cement production, the C4M team will explore the use of alternative minerals, potentially including drilling mud, which could form its cement in situ. They will identify materials with geologically stable mineral phases and consider inorganic coatings that can create durable well casings resistant to high temperatures and harsh environments. In some cases, these coatings may offer such effective protection for metal casings that traditional cement would no longer be necessary.
This ambitious research initiative will encompass laboratory experiments and computational modeling, analyzing and predicting the performance of these innovative composite materials from the atomic to the macroscopic scale and over varying timeframes, ranging from seconds to years.
The C4M research will leverage the expertise and facilities at Brookhaven, including the National Synchrotron Light Source II (NSLS-II) and Center for Functional Nanomaterials (CFN), as well as collaborate with partner institutions such as the Advanced Light Source at DOE's Lawrence Berkeley National Laboratory, DOE's Sandia National Laboratory, DOE's Lawrence Livermore National Laboratory, and DOE's Los Alamos National Laboratory. Additionally, four universities will be part of this collaborative effort: University of Texas at Austin, Cornell University, University of Illinois Urbana-Champaign, and Princeton University.
Thomas Butcher, a research engineer leading the energy conversion group in Brookhaven Lab's Interdisciplinary Science Department, expressed enthusiasm for the initiative, stating, “Through this Center, an incredibly talented team has been assembled to develop the fundamental understanding of the materials needed to push back the pressure and temperature boundaries of geothermal power production”
