Genset HH20B Locomotive in BNSF Colors. This locomotive was unveiled in 2009 by the BNSF Railway. Instead of using conventional diesel fuel, it is powered by hydrogen fuel cells. It is called the HH20B, a hydrogen-hybrid switcher locmotive based on the GG20B Green Goat diesel-hybrid switcher built by Railpower Technologies Corp. of Brossard, Quebec. The GG20B is powered by a 300 hp 4-stroke Caterpillar diesel-engine and a battery pack with a combined tractive output of 2,000 hp. On the HH20B, diesel engine is replaced by hydrogen fuel cells. Hydrogen storage is in a set of tanks installed on top of the long hood of the locomotive in a heavily vented enclosure, above the batteries. Reskins permitted with permission of me, the author, Dave Snow.