US green shipping project developer Switch Maritime is claiming a world's first with the compressed hydrogen bunkering of its prototype zero-emissions ferry.

The 75-passenger Sea Change, which is to be delivered in 2022, is being completed at the All American Marine yard in the US state of Washington, where it will be the first in a series of sister vessels. It is now undergoing final operational trials before delivery to serve passenger traffic in the San Francisco Bay area in California.