Abstrakt: |
The transcritical CO2 (T-CO2) power cycle using low temperature waste heat is a promising technique for energy saving and environmental protection. However, according to the literature, there is no commercialized unit in service yet. This study provides developers a reference to shorten the design phase of the T-CO2 cycle commercialization process. A sensitivity analysis of the system performance, i.e., thermal efficiency and net power output, regarding the isentropic efficiencies of pump ( η p ) and expander ( η e ) and the heat source temperature ( T h , i n ) has been carried out using MATLAB and NIST REFPROP database. Simple and recuperative configurations are investigated based on their own optimal working pressures. The results show that the enhancement of η e has a greater influence on improving the system performance, but the improvement will diminish as η p , η e , and T h , i n increase. Although better system performance can be achieved with higher η p , η e , and T h , i n , the cost of the system equipment will also increase due to the higher optimal working pressure. In addition, increasing η p and η e will negatively affect the effectiveness of the recuperator. Therefore, the turbomachinery efficiencies and the heat source temperature should be considered simultaneously for the most cost-effective system design. [ABSTRACT FROM AUTHOR] |