Furthermore, green/clean energy is an always developing sector and that more locomotives may be added to the list, while some will no longer meet current standards.
Brandt Road-Rail is a company that mainly produces road–rail vehicles, especially railcar movers and maintenance of way equipment.
[4][5] In addition, in 2006, it also built a single prototype genset locomotive.
Motive Power and Equipment Solutions was a locomotive manufacturer and rebuilder active in Greenville, South Carolina from 1999 until 2022.
In 2009, a company called Vehicle Projects, in cooperation with BNSF Railway, rebuilt one Railpower GG20B locomotive into a prototype hydrogen-powered locomotive, called an HH20B.