Energy Department investments in adapting play fairway analysis to geothermal exploration could yield a potential 30 gigawatts of additional power from energy hidden deep in the Earth. In this poster, the University of Nevada at Reno illustrates the discovery of blind geothermal systems in the Great Basin Region, which spans 5 western states. source: James Faulds, Nevada Bureau of Mines and Geology
Geothermal energy today has expanded its horizons beyond traditional, surface-identified hydrothermal resources to include blind hydrothermal systems—those without surface expression—alongside enhanced geothermal systems (EGS) and low-temperature systems. These varied types of geothermal resources comprise a sizeable potential for economic opportunity in America, with the capability to significantly increase power generation, direct use, and other applications from geothermal energy.
However, major questions remain as to how to best locate and qualify these resources. Without a tested screening criteria, the search for these blind systems can be time- and resource-intensive, with a low probability of success. Developing a systematic approach early in the exploration process will improve the success rate of geothermal development projects while reducing overall exploration costs, which will in turn improve access to financing for drilling.
The concept of "play fairway analysis" has been used to identify potential locations of blind hydrothermal systems and to describe geothermal opportunities in rift-zone settings. Borrowed from the petroleum industry, this tool incorporates the regional or basin-wide distribution of known geologic factors besides heat flow that control the occurrence of a particular example of a geothermal system. Conducting play fairway analysis in unexplored or underexplored basins or regions or using new play concepts in basins with known geothermal potential is central to this effort.
The Geothermal Technologies Office supported eleven Phase I projects and six Phase II projects to advance and adapt play fairway analysis. Selected awards spanned the country, from the Aleutian arc in Alaska to the Appalachian basin on the East Coast.
The resulting regional, basin-scale maps serve to help quantify and reduce uncertainty for geothermal energy exploration. By improving success rates for exploration drilling, play fairway analysis could significantly lower the costs of geothermal energy while opening up new areas to development.
