Electrochemical Approaches to Mitigating Mineral Scaling in High-Temperature Geothermal Systems

The expansion of geothermal power is essential to the clean energy transition. Elevated-temperature geothermal power plants face significant challenges with mineral scaling in critical infrastructure, including pipelines, wellbores, and surface equipment. Existing scale mitigation methods are insufficient due to (1) costly plant shutdowns and (2) adverse environmental effects. These issues could be mitigated by integrating geothermal power plants with advanced, electrochemical scale inhibition systems. Such integrated systems may employ (i) electrochemically- enhanced deposition devices and/or (ii) nanobubble generators, to achieve the same function as traditional scale inhibitors, but without plant shutdowns for maintenance or the risk of water contamination from chemicals. The proposed Phase I project will focus on modeling different configurations of such devices to identify more optimal system designs. These innovative systems are expected to significantly reduce, if not eliminate, the use of harsh chemicals, and increase geothermal plant efficiency, power output, and uptime. Gaia will identify more optimal ways of integrating (i) electrochemically enhanced deposition devices and (ii) nanobubble generators into geothermal power plants to provide more economical and environmentally-benign scale inhibition. Gaia will perform the following tasks for a number of different system configurations: Build detailed thermodynamic models. Build detailed techno-economic models. Presenting model results to industry stakeholders. Gaia will validate device performance and integrate geothermal power plant models using open-access databases, literature, models, and industry sources. Gaia will evaluate several potential configurations in terms of scale inhibition effectiveness, system-wide round-trip efficiency, capital and operating costs, and overall system performance, and will use existing geothermal power plants as benchmarks. Once favorable system configurations have been identified, Gaia will iteratively optimize these designs. Gaia will then down select (1) to (3) of the best performing system configurations for demonstration in Phase II. A goal of the Phase I project is to conduct a comprehensive feasibility study to identify optimal configurations of (i) electrochemically enhanced deposition devices and (ii) nanobubble generators to provide more cost-effective, environmentally-benign scale inhibition for geothermal power plants. These innovative, integrated designs will substantially increase geothermal electricity production, plant efficiencies, equipment lifetime, uptime, capacity factors, and lifecycle profitability. These innovative designs will also reduce reliance on harsh chemicals and harmful environmental impacts, and help to transition electricity to a greener future. The intellectual property from this work will be licensed to benefit electrochemical device manufacturers, nanobubble generator manufacturers, and geothermal power plant developers, owners, and operators globally.