Keywords: cogeneration systems, components, exergy analysis, gas turbines, sensitivity analysis, net power, exergy efficiency, unit costs, thermal systems, electricity, steam
Sensitivity analysis of component efficiencies on performance of a gas turbine cogeneration system
The performance of a 1000 kW gas-turbine cogeneration system was evaluated in terms of performance measures, such as net power, exergy efficiency of the system, and the unit costs of electricity and steam. The efficiencies of some components that have a significant affect on the performance were taken as physical variables. Sensitivity was evaluated by introducing parameters, defined as the ratio between the logarithmic differential of the performance measures and the logarithmic differential of the variables considered. The sensitivity parameters employed permit the ability to distinguish the variable that most significantly affects the performance of the system. The sensitivity analysis was found to be an efficient and convenient tool to evaluate the performance of the thermal systems.