Design/Evaluation of Solid Oxide Fuel Cell System and Electrode Reaction Modeling

摘要

It is important to develop a SOFC generation system having generation efficiency higher than 55% to compete with conventional systems of combined cycle. The results of the basic design/evaluation of a combined cycle power generation system using SOFCs in conjunction with a gas turbine are shown. Total generation efficiency (Eth) was analyzed from standpoint of plant size, cell performance, working temperature/pressure, steam carbon ratio, fuel/air utilization rations, and turbine inlet temperature. Cost/energy payback times (CPT/EPT) were calculated. An example of the result is Eth=68.3%, CPT=9.3y, EPT=0.7y at a working temperature/pressure of 1073K/0.4 MPa. Furthermore, modeling results of cathodic reaction mechanisms using La_(1-x)Sr_xMnO_3, La_(1-x)Sr_xCoO_3, Sm_(1-x)Sr_xCoO_3 electrodes and their importance for SOFC design are explained.