Virtual Energy Storage System Framework for Multi-Temperature Zone Buildings

Residential and commercial buildings serve as Virtual Energy Storage System (VESS) for the grid by adjusting power usage in Thermostatically Controlled Loads (TCLs) within a predefined temperature range. Their thermal inertia stores energy within the building envelope, allowing consumption adjustments without compromising consumer comfort. However, buildings often have multiple temperature zones, influenced by varying occupancy, insulation, and air-conditioning systems operation. Existing VESS modeling practices lack capturing comprehensive buildings' thermal dynamics, including 1) thermal mass of internal walls, convective heat loss due to air infiltration, and heat transfer from adjacent floors and rooms in multiple temperature zone environments, 2) occupants' heat release and airflow obstructions, and 3) available buildings thermal energy storage state, adequately. This paper proposes an improved VESS model that captures these comprehensive thermal dynamics of multistory buildings along with the impact of multiple temperature zones due to TCLs' switching and occupants' activity. Buildings' thermal energy storage state characteristics are considered to define the available energy state within the buildings. The results show that these realistic considerations significantly impact TCLs' power consumption and VESSs' flexibility potential across varying daily temperatures. Additionally, the obtained optimal operating temperature range of TCLs provides precise estimation for their regulation up and down flexibility potential, ultimately enhancing VESS effectiveness in grid balancing.