Incentive policies for building energy retrofit: A new multi-objective optimization framework to trade-off private and public interests

This study addresses the challenge of large-scale energy retrofitting of existing buildings, a key step in advancing energy transition and sustainability. Despite its importance, building retrofits face numerous barriers, including economic, social, and cultural factors. Public financial incentives are crucial to overcoming such obstacles, but they must be optimized to trade-off the interests of the two main stakeholders: the private (individuals) seeking comfort and cost savings, and the public (governments) focused on energy and environmental benefits. This research proposes a new multi-objective framework for optimizing incentive policies based on building type and climatic conditions. The framework combines EnergyPlus for simulation and MATLAB® for optimization using a brute-force Pareto approach. The methodology is applied to Italian residential buildings of the 1961–1975 period, using data from the TABULA project and representative climatic locations. The framework seeks to maximize two contrasting objectives, which represent the public and private perspectives, respectively. The former is the global cost saving after building retrofit, the latter provides the “profit” of public policies as ratio between primary energy saving and spending for incentives. Two kinds of design variables are considered, related to energy retrofit measures and public incentives, respectively. The optimization algorithm yields the Pareto solutions, which are then postprocessed to infer guidelines for both stakeholders. The private is informed about the most cost-effective retrofit solutions, the public is informed about the best incentive policies to promote a massive building energy retrofit. Furthermore, optimal trade-off solutions are identified to unify the two perspectives under a synergic action.