Enhancing renewable utilization through energy flexibility: lessons learned from a residential cluster

As climate change accelerates, buildings must adopt not only efficient envelopes and systems but also operational strategies that enhance sustainability. Building Energy Flexibility (BEF) becomes particularly valuable when scaled to Energy Clusters (ECs), where multiple buildings coordinate energy use. This study evaluates a cluster of 202 single-family houses in Lodz, Poland, where each building acts as a prosumer. Energy efficiency is achieved through deep thermal modernization, resulting in the full electrification of the cluster. Energy flexibility is assessed through energy and cost savings, using optimization based on Demand Side Management (DSM) techniques with weather and electricity price forecasts as key indicators. Results show that effective cluster-level management improves renewable energy utilization, lowers emissions, cuts costs, and enhances grid reliability. Results demonstrate the role of Energy Flexible Building Clusters (EFBC) in sustainable urban energy systems.