Cooling of Gas Turbines Inlet Air Through Aquifer Thermal Energy Storage

Abstract

The power output of gas turbines reduces greatly with the increase of inlet air temperature. Aquifer thermal energy storage (ATES) is employed for cooling of the inlet air of a gas turbine. Water from a confined aquifer is cooled in winter, and is injected back into the aquifer. The stored chilled water is withdrawn in summer to cool the gas turbine inlet air. The heated water is then injected back into the aquifer. A 20 MW Hitachi gas turbine, along with a two-well aquifer were considered for analysis. It was shown that the minimum power output of the gas turbine on the warmest day of the year could be raised from 16.30 to 20.05 MW, and the mean annual power output could be increased from 19.1 to 20.1 MW, and the efficiency from 32.52% to 34.54% on the warmest day of the year and the mean annual efficiency from 33.88% to 34.52%. The use of ATES is a viable option for the increase of gas turbines power output, provided that suitable confined aquifers are available at their sites.