Leader-follower game-theoretic method towards carbon-economy trade-off in a key construction project group.

Due to rapid urbanization and modernization, the construction sector now generates one third of all greenhouse gas emissions in China. Using an equilibrium strategy combined with the carbon allowance allocation, this study presents a synergistic Stackelberg model based on a construction project planning framework to deal with cumulative CO2 emissions. The bi-level model simultaneously considers the sequential decision-making relationship between the authority (leader) and the enterprises' interactive objectives and constraints. Unlike previous research, this bi-level model gives a holistic analysis of the interactivity of multiple stakeholders, thereby enabling the inherent conflicts and equilibrium between environmental protection and decision makers' profits to be reconciled and balanced. To deal with the bi-level model complexity, an interactive solution method that integrates an evolutionary mechanism and improved particle swarm optimization (IPSO) is designed for solving a construction supply planning problem. The robustness and practicality of the proposed methodology are then validated in a real world case, and sensitivity analyses under different carbon emissions quotas are also given. The results indicate that the methodology can systematically reduce carbon emissions in the Chinese construction sector, and when the authority has a strict emissions reduction altitude, construction practitioners are able to attain high carbon efficiencies; therefore, the model provides valuable strategy guidance for policymakers and business executives.