Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.
In arid regions, where cooling water supplies are limited
and highly regulated, combined cycle power plants (CCPPs) are
turning to air-cooled condensers instead of water-cooled
condensers. However, performance of air-cooled condensers
can decline as ambient temperatures increase and result in loss
of steam turbine power output. At the same time, as ambient
temperature rises, net output of the gas turbine also can decline
due to increased power consumption by the compressor and
reduced power output by the gas turbine. In this paper, it is
proposed to remedy these problems by pre-cooling the inlet air
to the air-cooled condenser as well as the compressor, using a
low-temperature thermal energy storage (TES) system. The
TES is maintained around 5ºC by an absorption refrigeration
system driven by the waste heat in the stack gases. A
thermodynamic analysis of a 500-MW CCPP incorporating the
above concept is presented.
