SOFC-gas turbine combined cycle system is able to attain extremely high efficiency over 70% (LHV). Mitsubishi Heavy Industries (MHI) has been developing SOFCs since 1984. Now, MHI is integrating SOFC with a gas turbine for a combined cycle power generation system. MHI has improved the components and the control technology for the combined cycle system; this includes improvement of the cell stack, verification of pressurized operation and control of SOFC module, and the combustor for low-calorie fuel. In 2006, MHI operated a combined cycle system with a maximum power output of 75 kW, for the first time in Japan. Now, MHI is ready to manufacture a 200 kW class SOFC-MGT combined cycle system, which will be operated in 2007.
For large-scale SOFC power generation systems, a shorter start-up time of SOFC cell stacks with relatively large heat capacity is one of the most important technological issues to determine the flexibility in SOFC system operation. In this study, start-up procedures have been examined to shorten the start-up time period. The conventional heating procedure using pre-heated hot air and self-heating by SOFC operation at low temperatures had a difficulty to shorten the start-up time period because of the limitation in power generation at lower temperatures. In this study, as an alternative start-up procedure, catalytic combustion at the SOFC cathodes is, for the first time, demonstrated to be useful on the system level. The applicability of the catalytic combustion to shorten the start-up time period has been verified numerically as well as experimentally by using a large-scale cell stack cartridge. This unique start-up procedure enables to operate SOFCbased large-scale power generation systems.
Pressurized solid oxide fuel cells (SOFCs) using a gas turbine for the bottoming cycle convert energy very efficiently. The performance of a tubular SOFC made by a plasma spray coating method was measured at levels of pressure between 0.1 and 0.59 MPa. The cell voltage increased with the operating pressure. Moreover, it was determined that polarization decreased under pressurization, using the current interruption. Anode performance was also measured with a reference electrode. The estimated concentration overvoltage from the measurement of permeability was used to estimate the activation overvoltage of the anode. The anode activation overvoltage was affected by the partial pressure of H 2 O instead than that of H 2 .
Mitsubishi Heavy Industries, Ltd. (MHI) and Electric Power Development Co.,Ltd. (JPOWER) started SOFC module development in collaboration in 1991. Since 2001 we have focused on improvement on SOFC module aiming for high reliability and lower cost. The 5kW-class Cartridge test with 104 cell-tubes was successfully accomplished in 2003. We also executed a dynamic simulation and thermal fluid analysis of improved SOFC module and control system development under atmospheric pressure. In 2006, we have succeeded in the operation of 25kW-class sub- module that will be a unit of highly scalable SOFC system. This module dose not need heating support to maintain the operating temperature, because the fuel exhaust gas from the SOFC module is burned in the combustor and used for heating supply air to SOFC module.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.