Three key reports from the Energy Department address water impacts in geothermal energy production. Two recently issued studies, produced by Argonne National Laboratory for the Department's Geothermal Technologies Office (GTO), highlight methods for economizing water use in geothermal applications. These reports complement a Department-wide report released in June that assesses water usage in multiple energy applications, including geothermal.
Geothermal Water Use: Life Cycle Water Consumption, Water Resource Assessment, and Water Policy Framework, now available through the Energy Department's Geothermal Data Repository, projects geothermal water demand over the next 20-30 years. The incremental increases from geothermal development in its current trajectory will likely be manageable in most basins, according to this study by Argonne National Laboratory. As EGS advancements lead to more commercial pathways and the resource base becomes more fully exploited, water conflicts could be mitigated with technological improvements that help minimize belowground water losses and favor lower quality water sources such as brackish or saline groundwater.
Life Cycle Water Consumption and Water Resource Assessment for Utility-Scale Geothermal Systems, also available through the DOE Geothermal Data Repository is third in a series of reports by Argonne sponsored by the GTO. By evaluating the water requirements of four power plant scenarios, including flash and binary systems, this work highlights the importance of utilizing dry cooling systems for binary and EGS systems and minimizing fresh water consumption throughout the life cycle of geothermal power development. Methods focus specifically on (1) collection of data to improve estimation of EGS stimulation volumes, aboveground operational consumption for all geothermal technologies, and belowground operational consumption for EGS; and (2) the mapping of the geothermal and water resources of the western United States to assist in the identification of potential water challenges to geothermal growth.
The Department's Water-Energy Tech Team report – The Water-Energy Nexus: Challenges and Opportunities – frames an integrated challenge and opportunity dialogue to address water use among energy technologies for the Department and its partners, laying the foundation for future efforts. Geothermal technologies are key among those described. Low- temperature and coproduced geothermal power, for example, are highlighted as a method to increase the productive use of waste heat. Other ways to optimize water use in geothermal applications include the use of alternative fluids that can replace fresh water in geothermal operations. Learn more about low-temperature and coproduced and hydrothermalresources.
In support of the Obama Administration's Open Data Policy, the Department deployed theNational Geothermal Data System (NGDS) this year – an online, open-source platform that facilitates discovery and use of subsurface geothermal data for research and energy production. This open source platform responds to one of industry's greatest barriers to geothermal development and deployment: the difficulty in accessing and integrating technical data in digital format. In addition, all Energy Department-funded geothermal projects will submit cutting-edge research data to the network through a dedicated interface called the Geothermal Data Repository (GDR). Already, industry is using the free, online tool to model geological features and locate and monitor subsurface reservoirs. The new Argonne National Laboratory reports are available on the Geothermal Technologies Office GDR.
The Geothermal Technologies Office (GTO) funds more than 150 geothermal research, development, demonstration, and analysis projects. Follow our progress with the 2013 Peer Review Report or view program achievements in the 2013 Annual Report.
SOURCE: U.S Department of Energy