Energy-sharing operation strategy of multi-district integrated energy systems considering carbon and renewable energy certificate trading

District integrated energy systems (IESs) have proceeded to the practice stage. A day-ahead (DA) coordinated operation strategy of multi-district IESs is proposed when the entities participate in the energy market (EM), the spinning reserve market (SRM), the natural gas market, the carbon market, and the renewable energy certificate (REC) market simultaneously. We adopt the scenario-based stochastic programming method and the two-settlement mechanism to measure the uncertainties brought by electricity prices, photovoltaic (PV) outputs, and loads. Considering the topologies of electricity, heating, and cooling networks, the energy-sharing mechanism and the integrated demand response (IDR) mechanism are both implemented. We study the overlapped benefits of renewable energy generation (REG) from carbon and REC markets and propose a concept of the green index (GI). Case studies demonstrate that the proposed strategy model and the evaluation indicator can not only contribute to the economical and eco-friendly operation of the multi-district league (MDL), but also stimulate the coupling and complementarity of multiple energies.