Modeling the Idaho National Laboratory Thermal-Energy Distribution System (TEDS) in the Modelica Ecosystem

Integrated energy systems (IES)—including the intimate coupling between thermal generators, the grid, ancillary processes, and energy storage—are becoming increasingly pertinent to the energy grid. To facilitate a better understanding of IES, Idaho National Laboratory (INL) has developed the experimental Thermal Energy Distribution System (TEDS) to test the interoperability of nuclear reactors, energy storage, and ancillary processes in a real-world setting. This paper provides an overview of the development of TEDS within INL’s Modelica dynamic process modeling ecosystem as part of the IES initiative. The model will bridge the gap between lab-scale experimental results and desired grid-scale energy solutions. Two simulation sets were run. The first was a 5-h test simulating a facility shakedown test, putting the facility through five potential operating modes and showcasing the ability of the valving, control sensors, and component controllers to meet system demands. The second case imposed a typical summer day demand on the system from a region with mixed commercial and residential electrical needs. In this case, the generator alone could not meet peak demand but instead required the thermal-storage unit to act as a peaking unit.