Polymer electrolyte fuel cells (PEFC) are expected to be commercialized at an early date and to be expanded progressively as a next generation type low-pollution and highly efficient distributed power supply. In order to realize a highly efficient and compact PEFC system, Mitsubishi Heavy Industries (MHI) is developing various types of component technologies such as those related to catalysts and polymer materials, reformers, major components such as cells, and systems. Using fuel reforming catalyst technology from among these advanced elemental technologies, MHI has successfully developed a multi-fuel hydrogen production method and a start-up/shut-down operation method without nitrogen by establishing a deterioration prevention technology using CO shift catalysts. As a result, MHI has taken a major step towards commercializing the PEFC system for distributed power supply, which places only a small load on the environment while providing significant economic advantages.