Design of Multi-Level Pumped Thermal Energy Storage Systems For Coupled Industrial Heat Supply

Abstract This study investigated the potential of pumped thermal energy storage (PTES) systems to aid in the decarbonization of industrial heat. More specifically, we investigate the feasibility of changing the operating conditions of PTES equipment to work as open-cycle heat pumps when no electrical charge/discharge operation is taking place. A novel integrated design is proposed, incorporating multiple heat storage temperature levels, which increases system flexibility. The feasibility of reusing the PTES equipment for the lower temperature heat pump operation is assessed. The integrated system performance is evaluated through a scheduling optimization problem. Results highlight the potential of the proposed integrated system to increase storage capacity and supply heat 20% more efficiently across multiple temperature ranges Additionally, it is 40% cheaper than an equally sized Li-ion battery. If implemented in a renewable heavy grid, it can meet substantial heat demands while achieving significant CO2 emissions reductions. These findings demonstrate the viability and environmental benefits of PTES systems as energy storage solutions integrated with industrial heat supply.