Utilization of a ??hort-??erm ??hermal ??nergy ??torage in a ??istrict ??eated ??ffice ??uilding

District heating is a cost-effective heat supply method that has to be flexible enough in the future for the integration of more intermittent renewable energies. Although short-term thermal energy storage has been equipped for this purpose, centralized storage is the most applied type. District heating substations in conventional high-temperature district heating networks are typically not equipped with thermal energy storage. The aim of this paper is to evaluate peak shaving potential by short-term thermal energy storage considering conventional high-temperature variations. Therefore, a 5 m3 hot water storage tank was integrated into a substation to supply heat to a Finnish office building. The water tank was directly charged by the district heating supply water and supplied heat for space heating, domestic hot water, and ventilation. Temperature control for the water tank was designed considering the district heating supply water temperature, return water temperature limitation and outdoor temperatures. The model of an office building connected the substation with a storage tank was established and simulated by the dynamic building simulation tool IDA ICE. The results show that it significantly decreased the office building daily peak power caused by the ventilation system morning start during the heating season. It reflected a higher peak shaving potential for colder days and had a maximum of 31.5% peak power cut.