Abstract In order to promote the low-carbon transformation of energy systems and the interaction between electricity supply and demand, this study developed a building energy flexibility optimization framework. This study proposed a multidimensional quantitative evaluation index for building energy flexibility based on time, power, electricity, and cost, and constructed an operation optimization model and flexible optimization strategy for the building energy system. Based on the typical residential building scenario of northern China, the flexible potential and carbon reduction effect of the comprehensive utilization of building thermal mass, heat pumps, and water storage devices were optimized and analysed. The results of the investigated residential building during heating conditions show that the maximum flexible power (reduction) using the building thermal mass coupled heat pump energy storage system reaches 188.1 kW, and the flexible energy is 596.3 kWh. Compared to the benchmark operating conditions, the building carbon emissions decrease by 161.94 kg CO2, with a carbon reduction rate of approximately 20.26%. Residential buildings coupled with heat pumps and energy storage devices can effectively shift electricity load from high to low carbon emission factor periods, further releasing flexibility potential into the grid and enhancing carbon reduction benefits.
Lu et al. (Fri,) studied this question.