Integrated combined heat and power system with thermal energy storage

March 13, 2020 | Case Study

Combined heat and power (CHP) systems are an efficient way to meet distributed energy and heat demands. By recovering exhaust heat that would normally represent a loss from electricity production for use on-site in space heating or industrial processes, overall system efficiency can increase from around 30% to near 90%. However, on-site heat demand is generally lower than on-site electricity needs, meaning that reaching such high efficiencies requires undersizing a CHP system for a facility's electricity needs. As a result, a CHP owner must often purchase additional power, weakening a CHP system's value proposition. To address this limitation, thermal energy storage (TES) has emerged as a promising route to further boost system efficiency by capturing more exhaust heat and to better match CHP power production with on-site electricity demand. In March 2019, Argonne National Laboratory (ANL) and microturbine developer Capstone Turbine Corporation began a joint research project integrating ANL's thermal energy storage system (TESS) with a Capstone natural gas microCHP unit.