Power Density in Geothermal Fields

Abstract

We estimated the power densities of 66 geothermal fields above 10 MWnet with more than 5 years of production history. Power density follows a log-normal probability distribution. The mean power density of the population is 15.4 MW/km2, the median is 12.0 MW/km2 and the standard deviation is 9.5 MW/km2. Power density is a function of average reservoir temperature and correlates strongly with tectonic setting. Fault-based systems tend to be low to moderate-temperature and have low power density, volcanic arc systems tend to be moderate to high-temperature and have moderate to high power density, and rift systems tend to be high-temperature and have high power density. The one major deviation from these trends is that high-temperature volcanic arc systems tend to have moderate to low power density which may be anti-correlated with temperature. One important reason for this may be that volcanic arc-hosted systems tend to be found in more purely compressional settings which may have limited permeability.