Modern Methods of Inlet Air Cooling for Gas Turbine Units

Abstract

Relevance: an increase in ambient temperature reduces the air density at the compressor inlet of gas turbine units (GTUs), which leads to a decrease in their power output and energy efficiency. Under conditions of growing electricity demand and the need to improve the efficiency of energy systems, the application of inlet air cooling technologies for gas turbine units becomes particularly relevant, especially for combined cycle power plants.

Aim : to conduct a comparative analysis of modern inlet air cooling methods for gas turbine units and determine their impact on performance, energy efficiency, water consumption, and economic indicators of power plant operation.

Methods: thermodynamic and techno-economic analyses of various inlet air cooling technologies were applied. Three methods were considered: evaporative cooling, fogging (high-pressure water injection), and absorption cooling. To evaluate water consumption, mass balance equations and water flow calculations for cooling systems and cooling towers were used.

Results: the study showed that the use of inlet air cooling systems increases the performance and energy efficiency of gas turbine units. Evaporative cooling increases power output by 5–10% and is characterized by low capital costs, but its effectiveness depends on air humidity. Fogging provides a higher power increase of up to 15–20%, but requires higher water consumption and high-quality water treatment. The absorption chiller demonstrates the greatest increase in power output (up to 20–25%) and operates effectively under various climatic conditions; however, it requires significant capital investment and complex infrastructure.