Numerical study on carbon emissions and economics of a high temperature heat pump system for an industrial process

Research to achieve net-zero is actively being carried out. In industrial processes, large amounts of carbon are emitted to product thermal energy, and there is a growing interest in electrification technologies to reduce this. While electric heaters and heat pumps are representative technologies for electrification, research to determine which technologies can economically contribute to carbon reduction is necessary. In this study, transient model for a heat pump and thermal energy storage (TES) was developed, and the CO₂ emissions and economic feasibility were analyzed. When coupled with photovoltaic power and battery energy storage (BESS), it was found that the heat pump can reduce CO₂ emissions more economically than electric heater. Transient analysis was performed for the case of coupling TES with heat pump instead of BESS and it was found that CO₂ emissions vary from 276 to 231 g/kWh_th with and without the TES, respectively. When combining the heat pump and photovoltaic system with TES or BESS, the nominal levelized cost of heat to reach the same level of CO₂ emissions is 11.6 % higher for the BESS-coupled system. Up to certain level of CO₂ emissions, the TES-coupled system is economically viable, but minimum emissions can be achieved with the BESS-coupled system.