Hydrogen energy is produced when hydrogen undergoes an oxidation reaction. The only end product is water; it has no emissions of toxic substances, such as nitrogen or sulfur oxides, which occur with fossil fuels. Hydrogen has the advantages of being colorless and odorless and having a high burning temperature of about 3,000°C, and it thus is a focus of attention as a new clean energy. In Japan, the national government is promoting hydrogen research, and its hydrogen-related manufacturing technology is considered to be world class.