The distributed energy system becomes increasing popular in recent years because it can realize the cascade utilization of primary energy and integrate with renewable energy, which is energy efficient and environment-friendly. Thermal energy storage system can supplement the absorption chillers or boilers to utilize the surplus cooling and heating energy so that the primary energy efficiency of the system can be improved. This study investigates the feasibility of distributed energy system integrated with thermal storage systems in hot summer and cold winter areas. The energy and economic performance of the integrated system is evaluated and compared with that without thermal storage system. The impacts of climates and building mix are analyzed. Results show that the improvement of the energy and economic performance by using the thermal storage system is limited. The primary energy efficiency of the distributed energy system is improved by around 2%. The payback period is more than 20 years.
Keywords distributed energy system, thermal energy storage, energy saving, primary energy efficiency