Research On Zero CO₂ Emission SOFC Hybrid Power System

The problem of Climate change and greenhouse gas emissions is becoming more and more serious,, which makes people realize that energy systems established in the 20th century can not meet the requirements of cleanness, high efficency,, economy and safety in the future society. Energy development is facing a huge challenge. In order to meet the need of sustainable development in the 21st century, people continuously put forward the new concepts of energy conversion, the new mechanism of thermal physical process, the new ideas of thermodynamic cycle and the new development model of energy power system. In order to realize the higher efficiency and zero CO2 emmission of coal fired power generation system, the Solid Oxide Fuel Cell (SOFC) hybrid power system has been studied in this paper.The first section sums up the basic structure, working principle and advantages of the fuel cells. Based on Aspen Plus soft, the SOFC system model is developed. Because the simulation results are very close to the literature reference data and experimental data, the model is accurate and reliable. It can be used for the complex system simulation.The second section establishes the zero CO2 emission SOFC hybrid system with the small power scale, and the exergy loss distributions of the system are revealed in detail, the results showed that the exergy losses of fuel cell stack, after-burner chamber, and CO2 compression unit are bigger. To minimize the exergy loss and improve the overall system efficiency, some measures can be taken such as improving the temperatures of cell stack and turbine inlet, designing the reasonable heat transfer mode and optimizing the operation parameters.The third section proposes the three zero CO2 emissions SOFC/GT/ST hybrid power systems according to the different cooling measures, and their performances are analyzed in detail. The result shows that the scheme (a) with the steam injection cooling mode has the biggest superiority. The achievements obtained from this paper will provide the valuable reference for further study on the zero CO2 emission SOFC hybrid system with high efficiency.