Comparison of Promising Cogeneration Technologies Based on Fuel Efficiency Criteria

The energy efficiency of combined generation of electric and thermal energy based on gas turbine and combined-cycle technologies is estimated in comparison with steam power plants, as well as separate generation at condensing power plants (CPP) and boiler houses, under current conditions and in the foreseeable future. The efficiency of cogeneration under modern technological conditions is shown. According to the calculations, at present, the implementation of combined generation of electric power and heat based on modern power plants during the modernization of CHPPs will provide savings of 17 to 35% of fuel compared to separate generation. In the future, upon reaching the average annual efficiency of CPPs at the level of 55%, the fuel savings will decrease, but will remain and will amount to 6 to 23%. A comparison of domestically produced power plants that can be widely used in the modernization of steam turbine CHPPs is carried out. The integrated technical and economic indicators are proposed, taking into account the dependence of gas turbine and combined-cycle plants on the ambient air temperature in combination with the heat supply mode. The fuel efficiency of cogeneration is estimated for heat load schedules with a share of the base year-round load in the range from 7 to 25%, typical for consumers in the Russian Federation (RF). The advantages and limitations of different cogeneration technologies in the climatic conditions of the regions of the RF are shown. The estimates cover a wide range of climatic conditions of the regions of the RF, where large and medium-sized CHPPs are located.