THE STUDY OF CAPACITY ENHANCEMENT OF A 37.5 MW GAS TURBINE USING THE CHILLIED WATER THERMAL ENERGY STORAGE SYSTEM

Combustion gas turbines are constant-volume engines for which shaft horsepower is proportional to the combustion air mass flow. The gas turbine engine output improves if the air temperature is decraesed at the compressor inlet to increase the air density. Cooling the inlet air to the combustion turbine increases the mass flow rate and improves the combustion turbine performance. Using the Thermal Energy Storage for combustion turbine inlet air-cooling offers an economical solution when short duration capacity enhancements are required. This paper reviews the (Thermal Energy Storage Inlet Air Cooling) TESTIAC impact on the performance of a 37.5 Mw gas turbine located at the Kish Island Power Generation Plant in Iran. The study of the power demand in each month indicates the same pattern. They show two peaks, one at the time interval from 10:00 to 13:00, and the second peak at the time interval from 20:00 to 24:00. The high temperature ambient substantially reduces the power plant output, in the Summer Season (June 1st to Oct. 31) when the power sale is most valuable. Inlet air chilling with TESTIAC will be installed soon in the Kish Island to increase the output during "on-peak" (7 hours/day) in the summer when maximum unit performance is required. The designed TESTIAC system is capable of lowering the inlet air temperature of PG6541 B Combustion turbine (CT) to 7.2oC at the 450C ambient temperature of a hot summer day. The combustion turbine capacity enhancement will be around 5.1 Mw. A Chilled Water Storage System uses inexpensive off-peak (17 hours/day) power at night to generate the stored nergy in the chilled water for inlet air-cooling during peak demand (7 hours/day) periods. An Ice storage system was also studied in the project. However, this system was not found economically feasible. Therefore it was not selected.

Keywords:

GAS TURBINE , POWER ENHANCEMENT , THERMAL STORAGE , CHILLED WATER