Flexibility potential of residential buildings for distribution grid services

Strategies such as the incorporation of renewable energy sources and the decarbonization of the residential sector are currently being adopted in Germany, thus posing additional stress on the electricity grid. To reduce resulting grid reinforcement costs, this study analyzes the potential of residential buildings to effectively use their thermal storage for demand response and optimally adapt the operation of their heat pump to minimize grid stress. Eight German residential building archetypes are simulated using co-simulation as well as the Rolling Horizon Approach, which significantly reduces computational costs. Their energy bands are derived allowing to quantify the minimum and maximum heat pump energy consumption during a typical autumn week to ensure comfortable indoor temperatures (known as flexibility). They are introduced to two German distribution grids with different constellation of technologies: one with a high share of photovoltaic energy generation and another with a high percentage of loads (agricultural, industrial, residential and retail). By means of a quadratic problem formulation with linearised alternate current power flow constraints, the heat pump operation is optimized. Results show that the potential of residential buildings with heat pumps to reduce grid expansion costs is limited, and strongly depends on the nature of the electricity grid as well as on the climatic conditions of their location. While an optimal heat pump operational strategy reduces reinforcement costs in grids where they are abundantly represented, it does not have an impact on grids where they not. In the simulated photovoltaic-dominated grid, electricity curtailment is minimized by increasing the heat pumps energy demand when the energy generation is high. It can be therefore concluded that the incorporation of heat pumps to the studied electricity grids has not been problematic, but has rather reduced the necessary grid expansion caused by the introduction of photovoltaic energyObjectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.2 - Per a 2030, augmentar substancialment el percentatge d’energia renovable en el con­junt de fonts d’energiaObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.3 - Per a 2030, augmentar la urbanització inclusiva i sostenible, així com la capacitat de planificar i gestionar de manera participativa, integrada i sostenible els assentaments humans a tots els païso