Abstract: Affected by the economic downturn, the average load rate of thermal power units continues to reach the recorded low level, and peak shaving energy consumption increases sharply. In this paper, a qualitative analysis is made on the impact of joint peak shaving of pumped storage power units and thermal power units on the pollutant treatment cost, and a joint peak shaving optimization model of pumped storage power units and thermal power units is established with consideration of pollutant treatment cost. Based on the mixed integer programming principle, the simulation calculation model is solved. The results show that during a daily peak period, the two-shift joint peak shaving operation of the pumped storage power units and thermal power units can effectively reduce the cost of denitration, desulfurization and dust processing, as well as the carbon emissions cost and the total cost of power generation. Compared with the low load peak shaving method, the proposed method can effectively avoid the problem of denitrification system to exit operation due to the too low temperature at the inlet, as a result, having more obvious cost impact. It is proved that with full consideration of pollutants treatment costs, the two-shift joint peak shaving method of the pumped storage power units and thermal power units can effectively solve the current high energy consumption problem of thermal power unit for peaking shaving. The rationality and practicability of the proposed model and method is verified, and it is also proved that the objective of ultra low pollutant emission can be reached for regional system peak shaving.

Key words: pumped storage power, thermal power unit, two-shift, pollutants, treatment cost, ultra low emission