Conclusions from Comparing genGEO to GETEM and GEOPHIRES 1. The mass flowrate of the heat extraction fluid does not need to be a user input in technoeconomic tools for geothermal power plants because there is an optimal mass flowrate that minimizes cost or maximizes power for a given plant. In geothermal power plants, there are thermodynamic relationships between the reservoir, wells, and power cycle that are functions of the mass flowrate, thus changing the flowrate can substantially increase cost or decrease power (Figure ; Figure ). Despite this fact, geothermal resource assessments have used a single mass flowrate across all potential power plants. For example, the default mass flowrate of 110 kg/s per well was used within GETEM to create U.S.-wide supply curves for all hydrothermal binary geothermal power plants in the 2019 GeoVision analysis. Allowing users not to specify the mass flowrate, and instead determining the mass flowrate based on power or cost optimizations, is one of the methodological contributions that genGEO makes to techno-economic assessment tools.