Energy-flexibility strategy for residential blocks with multiple morphologies based on energy, economy, and carbon reduction performance

Incorporating energy-flexibility strategies into urban blocks can yield substantial benefits in terms of energy efficiency, economic viability, and carbon emission reduction. This study proposes an energy-flexibility strategy aimed at enhancing the energy and economic performance of a residential building system that integrates photovoltaics power generation, electric vehicles charging, and battery energy storage system. Simulation models were developed to comprehensively evaluate the performance of this strategy in residential blocks with different morphologies in Shenzhen, China. Simulation results indicate that the energy-flexibility strategy can reduce the average annual grid energy consumption of the block by 41.6% for multi-story buildings, 22.6% for small high-rise buildings, and 12.5% for high-rise buildings compared to the benchmark system. The average levelized cost of electricity over the entire lifecycle is 67.1%, 40.5%, and 29.7% lower than that of the benchmark system for multi-story, small high-rise, and high-rise buildings, respectively. The average peak-time grid flexibility factors for multi-story, small high-rise, and high-rise blocks reach 0.01, 0.17, and 0.35, significantly reducing the net grid power inflow during peak electricity demand periods. The total carbon emissions over the lifecycle can be reduced by 11.8% to 67.7%, with particularly notable carbon reduction benefits observed in multi-story blocks. Compared to traditional building-attached photovoltaics systems, blocks employing the energy-flexibility strategy achieve remarkable economic benefits and peak-shaving advantages, albeit at the cost of slightly higher grid power inflow and carbon emission.