Cooperation among multiple stakeholders in the complementary integration of renewable energy sources (hydro

wind

and solar power) can enhance the incremental benefits of each participant as well as the overall efficiency of the cooperative alliance. The interest coordination mechanism stands as a pivotal element in the development of such multi-energy complementary systems. This study adopts a three-tier hierarchical model comprising a primary layer

secondary layer

and tertiary layer. The primary layer is an efficiency-oriented cooperative game model based on collective rationality

which determines the installed capacities of hydro

wind

and solar power within the alliance by requiring that the incremental financial internal rate of return (FIRR) exceed the benchmark FIRR for joining the hydrowind-solar integrated alliance. The secondary layer is a participation-oriented non-cooperative game model rooted in individual rationality. Building on the installed capacities defined by the primary layer

it calculates the FIRR for each energy type when developed independently and compares it with the incremental FIRR of alliance participation to assess the willingness of stakeholders to join the alliance. The tertiary layer is an equity-oriented bargaining game model. Leveraging the incremental FIRR from the primary layer and the individually rational FIRR from the secondary layer

it ascertains the equitable FIRR for each stakeholder through bargaining based on the principle of fairness.A case study of a specific renewable energy multi-energy complementary system validates the feasibility and effectiveness of the proposed mechanism.