Background. Russia has the largest reserves of natural gas in the world. In our country, trunk gas pipelines are traditionally used to deliver natural gas from the extraction site to consumers. The construction, maintenance and operation of trunk gas pipelines require considerable financial resources, so reducing the costs of pumping natural gas by increasing the energy efficiency of gas turbine units due to integrated use of secondary energy resources is of considerable interest.
Materials and methods. The conducted studies have been carried out using available methods of thermodynamic calculation of the internal combustion engine cycle, determination of the components of its thermal balance and thermal calculation of equipment for the utilization of secondary thermal energy resources.
Results. After the integrated use of secondary energy resources, an analysis of the expenditure part of the energy balance of the gas turbine unit has been carried out. It has shown that 16,000 kW (41,7 %) of the thermal energy of the incoming part of the energy balance is used to drive the gas compressor, 9,899 kW (25,8 %) is used to drive the low- and high-pressure compressors, 11,311 kW (29,4 %) is discharged with combustion products, and external heat losses amount to 1,152 kW (3 %).
Conclusions. Compared with the basic gas turbine unit, heat losses with combustion products have decreased by 65 %. The energy-saving measures to use secondary energy resources have allowed us to reduce the consumption of natural gas during the operation of the gas turbine unit in the nominal mode compared with the basic gas turbine unit by 23 %. Considering the generation of electric energy due to the use of energy of excess pressure of the flue gas and heat during heating of the network water of the heat supply system of the gas pumping station, 35420 kW or 92,2 % of the supplied energy has been used beneficially.