Gas Turbine Bottoming Cycles For Cogenerative Applications: Comparison Of Different Heat Recovery Cycle Solutions

With all the advancements made in the gas turbine technologies in the last 7 decades, a large amount (approximately 60%) of the thermal energy in the gas turbine exhaust is released in to the environment. This discharged heat could be profitably used not only in thermal utilities but also as an intermediate temperature heat source for the bottoming cycles producing electric power. This paper provides a systematic thermodynamic performance evaluation and comparison among the three different waste heat recovery solutions, namely, the Inverted Brayton Cycle, the Bottoming Brayton Cycle and the Organic Rankine Cycle. The results obtained from the parametric analyses of the CHP systems clearly identify advantages and limitations of the gas turbine technology and its size when combined with the three bottoming cycles evaluated in this study. A detailed discussion on the obtained results is presented in this paper.