With the rapid development of wind power generation and photovoltaic power generation, the phenomenon of wind and solar abandoning becomes more and more serious in the operation of power systems, and the microgrid is a new operating mode of power systems which provides a new consumption mode for wind power generation. With the increasingly close connection among energy resources and people's increasing awareness of environmental protection, this paper establishes a microgrid optimal scheduling model with a combined heat and power system, in consideration of environmental costs. This model aims at the lowest comprehensive cost, at the same time taking into account the emission reductions of SO 2 and NO x , considering the cost of power generated by the micro-generator, environmental cost, the related cost of battery, operation and maintenance cost of wind power, and photovoltaic power generation. The related constraints of thermal balance and power balance are also considered during microgrid system operation. The established model is solved with an improved particle swarm algorithm. At last, taking a microgrid system as an example, the validity and reliability of the proposed model are verified.Energies 2018, 11, 2493 2 of 23 microgrid system with wind and light storage [11,12], to achieve the goal of reducing the total operating costs and SO 2 and NO x emissions, has become an urgent problem to be solved.In recent years, the related research on microgrids has achieved certain results. In [13], Mao et al. comprehensively considered the operating cost, pollutant discharge, and operational risk, and established a multi-objective optimization model based on microgrids. It considered the impact of distributed power output volatility on microgrid operation, which can effectively improve the operation and management level of microgrids. In [14], Wu et al., based on the model of each power source in the microgrid, established the scheduling model when grid-connected, and proposed the mixed integer programming method applied to the optimal scheduling of the microgrid, which proves that this method has strong advantages in both computation time and calculation accuracy, and can provide fast and accurate scheduling information for short-term and ultra-short-term energy management of microgrids. In [15], Fubara et al. comprehensively considered the power balance and heat balance in a microgrid, and took the lowest operation cost as target, while considering the energy utilization rate, and two different operational strategies were proposed, which were applied to three different models. Through calculation, the operating costs under each power generation strategy were compared and verified. This contributed to the improvement of the energy efficiency of the microgrid. However, in [14,15], the investment of renewable energy, such as wind power and photovoltaics, is not taken into account, which can reduce the emission of pollutants to a certain degree. In [16], Thompson et al. established a multi-objective economic scheduling...
