2008 MIT Energy Conference: The Path from Conventional Hydrothermal to Nationwide Engineered Geothermal Systems
While US geothermal electric capacity stands at only 2544 MWe, there are over 2500 MWe of conventional geothermal projects currently being developed in the United States, and that number could more than double by 2015. Despite this growth, conventional geothermal energy is limited in its ability to scale due to its dependence on the presence of a natural hydrothermal resource to exploit. Engineered Geothermal Systems (EGS) are artificially created geothermal systems made by hydraulically stimulating a rock formation to create a network of interconnected wells and then circulating fluid through the system. Since EGS can theoretically be developed wherever there is a high temperature rock formation, the resource base is huge. EGS holds the potential for large scale, baseload, renewable energy. However, the technology is still in the early stages of development and deployment. For EGS to achieve significant scale, there must be advancement in technologies such as drilling and reservoir stimulation, in addition to demonstration projects and consistent policy support. Since the first EGS fields will be developed on the edges of conventional hydrothermal fields and will utilize many of the same technologies as conventional geothermal plants, conventional geothermal development is critical to the future of EGS as it establishes the infrastructure, industry and knowledge base needed to harness the EGS resource. Geothermal energy has the potential to play a significant role in the US energy mix, but could also remain a relatively unknown bit player if not properly developed. This panel highlights some of the recent developments in unlocking the potential of the EGS resource while discussing key challenges and opportunities going forward.