High-Reliability Cements for Enhanced Geothermal Systems

The nation is currently faced with the significant challenge of developing alternative sources of energy to meet our growing energy needs in a sustainable and environmentally responsible manner, while reducing carbon emissions. For a significant population of the western United States and the world that live near geothermal resources that may be exploited by enhanced geothermal systems (EGS), the development and maturation of EGS can result in dramatic improvements in the local economies and industries. However, key innovations, including the development of highly reliable and durable cement compositions that can survive and perform in the high-temperature, high-pressure EGS environment characterized by significant thermal gradients are needed for the commercial viability of EGS. In the proposed work, HiFunda and Rutgers, The State University of New Jersey will work together to develop a new hybrid reinforced cement composition that is pumpable, and provides the required reliability and durability in the high-temperature environment. The work will include materials processing, materials property evaluation, mechanical testing and thermal stress testing. After successful proof of concept demonstration in Phase I, Phase II will focus on scaling up and optimizing the basic concepts, ultimately leading to development of materials and manufacturing technology for large scale production and application of the new hybrid reinforced cement. Commercial Applications and Other Benefits: Successful execution of the proposed project work will result in a new cement composition that can enhance the reliability and reduce the delivered cost of energy from EGS, which will effectively enhance the commercial viability of EGS. Specifically, improvement in cement technology is part of a suite of technologies that will enable access to deeper, hotter regions in high grade formations or to economically acceptable temperatures in lower-grade formations. Geothermal energy from EGS represents a large, indigenous resource that can provide base-load electric power and heat at a level that can have a major impact on the United States, while incurring minimal environmental impacts. Further, EGS provides a secure source of power for the long term that would help protect America against economic instabilities resulting from fuel price fluctuations or supply disruptions.