Research on the scheduling of unit operation mode for combined heat and power plants considering new energy consumption in heating season

Abstract

China aims to peak carbon dioxide emissions before 2030 and achieve carbon neutrality before 2060. The traditional coal power plants need to reduce theirs power load as much as possible to reduce CO2 emissions and improve the consumption capacity of intermittent renewable energy. Nevertheless, in part of northern China, areas with a high proportion of combined heat and power (CHP) units in coal power, CHP units need to provide heat load during heating season so that the flexibility of power load adjustment for CHP units is restricted. The plant minimum operation mode model is proposed to excavate the plant-level lower boundary of power load. By analysing the heat-power coupling mechanism of each unit, under different unit commitments, the plant-level lower boundary of power load can be calculated through dispatch heat load reasonably. Then the scheduling scheme of optimal unit commitment for plant is obtained. The comparison of results with the actual operation of a case CHP plant shows that the consumption capacity of renewable energy can be increased by 1.92 billion kWh and the CO2 emissions of the reference plant could be reduced by 52.5% under the scheduling scheme of optimal unit commitment during the heating season. The reduction of CO2 emissions for the scheduling scheme of optimal unit commitment will remain more carbon allowance which can bring revenue from carbon trade market. The scheduling of unit operation mode provides a way of operation under the current policy and environmental background, how to depress the power load of CHP plants and reduce CO2 emissions in heating season.