California is spending $127 million to buy six hydrogen-powered passenger trains, building on an earlier order of four of the zero-emission vehicles from Stadler Rail.

The California Department of Transportation (Caltrans) announced the latest purchase Feb. 14. It is a follow-up to the $80 million contract with Stadler Rail, signed in October, for four hydrogen-powered passenger trains.

The contract includes options for up to 25 additional hydrogen trains on top of the first four.

The first trains are expected to start paid service in 2027. They will run mainly between Merced and Sacramento but may also be used in demonstrations across the state.

“California continues to lead the way to a cleaner, more connected transportation system,” California Transportation Secretary Toks Omishakin said in a statement. ‘By expanding our fleet of hydrogen-powered passenger train sets, we are showing we are serious about deploying innovative and sustainable transportation options for the people of this state.”

Omishakin said previously that the hydrogen trains will complement California’s future electrified high-speed rail line. The first hydrogen trains will run along an expansion of the existing Altamont Corridor Express (ACE) and Amtrak San Joaquin routes that will eventually connect with high-speed rail between Merced and Bakersfield.

Funding for the hydrogen trains is coming from Gov. Gavin Newsom’s $10 billion zero-emission vehicle package. The multiyear package includes $407 million for the California State Transportation Agency to buy or lease clean bus and rail equipment and infrastructure.

The multicar trains from Stadler will use hydrogen fuel cells and won’t need a locomotive.

The design, which Stadler calls the Fast Light Intercity and Regional Train (FLIRT), makes the trains lighter, less expensive and more efficient than traditional locomotive-hauled coaches, Caltrans said.

Stadler initially worked with the San Bernardino County Transportation Authority (SBCTA) on developing the hydrogen-powered trains. That work led to Caltrans’ purchase in October of what the agency called the first zero-emission, hydrogen intercity passenger trains in North America.

Stadler is a Swiss company with a U.S. division based in Salt Lake City. Stadler said the new hydrogen train has been tested extensively in the U.S. and Switzerland.

Caltrans’ purchase agreement with Stadler in October came just before the U.S. Department of Energy announced that California will receive up to $1.2 billion as one of the nation’s seven potential regional hydrogen hubs. (See DOE Designates Seven Regional Hydrogen Hubs.)

Among the goals of the California hub are to decarbonize public transportation, heavy-duty trucking and port operations.