Fuel cell buses have started appearing on Tokyo's streets. The Tokyo Metropolitan Government is working to popularize fuel cell vehicles, buses, etc. toward the realization of a hydrogen-based society. In recent years, private companies have begun operating fuel cell buses with subsidies from Tokyo Metropolitan Government and the national government. The hydrogen bus, which does not emit carbon dioxide, creates no engine noise and is very quiet. Currently, Tokyo Metropolitan Government and the national government are also focusing on expanding the development of hydrogen stations and try to increase the operation of fuel cell buses.