Capacity Enhancement of Gas Turbine Power Plant Using Inlet Air Cooling by Thermal Energy Storage

Abstract

During the last years, gas turbines have been widely used to produce electricity power. Gas turbine power plants mainly met the increase on load at peaking load. However, gas turbine power plants have the disadvantages of decreases in maximum power output in the summer daytime, which reduces the availability of gas turbines. One of the ways to avoid aforementioned disadvantage is making by cool inlet air of the gas turbine to increase the density, improve the gas turbine performance and augment maximum power output. In addition, one of the ways for cooling the inlet air is to make ice by driving electric compression refrigerators using during off-peak load. Store it in ice storage tank and use it for cooling the inlet air during the on-peak period. Thermal energy storage for combustion turbine inlet air cooling offers an economical solution when short duration capacity enhancements are required. The objectives of this research is to investigate the effect of inlet air cooled by ice storage in Garri power plant station, expected results of the thermal energy storage for combustion turbine inlet air cooling system are included and economical profits. A computer based calculation procedure using Excel worksheet was built, and applied to estimate the effect of the system on Garri power plant station. The calculation based on the plant data which is the combustion turbine model Alstom-GE PG-6551B, ambient air design is 35.7 DB/ 30% RH, and enthalpy 64.04 kJ/kg, inlet air design 15 DB/ 100% RH, and enthalpy 42.01 kJ/kg, air mass flow 518300 kg/hr @ 15, and peak cooling hour is 4 hours/day, 5 days/week. The results for the designing calculations were 20.6% increased in power generation or 6.1MW increased in capacity and 5.2% increased in efficiency. The project installation cost about 4103599 SDG and 2.1 years payback period of the system.‬