Understanding of the reservoir will be more important now than ever before with EGS and next-Gen geothermal technologies. Reach out if this challenge resonates with you and your current operations.
Exploration Geoscientist | Geothermal Lead at Teverra | Energy Transition Solutions Podcast Host | Thermal Thursdays
#ThermalThursdays This week we have seen major announcements coming from Fervo and FORGE, showing sustained flowrates from their respective enhanced geothermal wells. CEO of ResFrac, Mark McClure, had a follow up blog post discussing the importance of these results and the validation they bring to multistage, horizontal EGS well development. There’s an important point that flew under the radar that I need to highlight. As Mark suggested, the largest risk now to EGS is thermal degradation of the resource. It’s important to realize how serious this point could be. The heat in place is fundamentally the total heat that can be extracted from any given volume. How that heat comes out is a function of both the well design and what I would argue is more important, the resource and reservoir (i.e., the rock). Looking at the chart above (from Beardsmore and Cull, 2001), thermal conductivity (and other thermal properties) vary by rock type. That’s an obvious statement. Because thermal properties vary by rock type, the ability and rate at which heat will be extracted will vary, and this often then varies by play. This means the results outside Milford, UT, will look different than the results we would expect at Los Alamos and Fenton Hill if we were to restart that EGS with new drilling technology, or at Newberry Volcano, or in any major sedimentary basin. This will impact spacing, number of stages, well choke and/or pump rates – basically, the rock and the resource extraction will dictate reservoir management. These results emphasize ever more the need for high resolution subsurface understanding prior to drilling complete, full cost, production and injection wells. It’s a great time to be a geologist, and to a lesser extent, a reservoir engineer. #geothermal #oilgas #sustainability #energy #geologistjokes
