San Francisco launches world’s first commercial hydrogen ferry

Most ferries in the United States run on diesel fuel, with groaning engines that spew harmful emissions into waterfront communities. But in San Francisco, passengers on the city’s newest vessel will find the trip to be much quieter and cleaner as they zip around the bay.

On Friday, a hydrogen-powered ferry called Sea Change officially launched after more than six years in development. The vessel is the first commercial passenger ferry in the world to run entirely on hydrogen fuel cells — a technology that doesn’t directly emit carbon dioxide or toxic air pollution, just a little heat and water vapor.

On a breezy morning, city and state officials gathered at the downtown ferry terminal and climbed aboard the blue-and-white boat to celebrate its public debut. The ferry will begin a six-month pilot service on July 19, operating Friday to Sunday between the historic Ferry Building and Fisherman’s Wharf and at no cost to passengers.

Sea Change is owned by the startup Switch Maritime and was developed with support from a $3 million grant from the California Air Resources Board. A group of private partners are sponsoring the ferry’s demonstration run, including Chevron New Energies, United Airlines, and the Golden Gate Bridge, Highway, and Transportation District.

“California is a global leader in the fight against the climate crisis, pioneering new technologies to ramp up clean energy and cut pollution — that’s why the zero-emission Sea Change is so exciting,” California Governor Gavin Newsom (D) said in a statement on Friday. ​“I’m proud of our state’s role in advancing these innovations, and of our state’s public and private sector partners for bringing them to market and demonstrating their viability.”

Sea Change is launching as ferry operators in the U.S. and globally are facing rising public pressure to clean up their dirty fleets.

Many of America’s nearly 620 ferries rely on decades-old, inefficient diesel engines, making them some of the largest emitters among commercial harbor craft. They also typically operate around densely populated and marginalized communities, exposing people to health-harming pollutants such as particulate matter (PM) and nitrogen oxide (NOx) emissions.

In California, where ferries represent only 2 percent of harbor craft, the vessels are responsible for 11 percent of total PM2.5 emissions and 15 percent of NOx emissions within the maritime category, according to the California Air Resources Board. In 2022, the regulatory agency adopted a rule requiring all short-run ferries in the state to be zero-emissions by the end of 2025.

A growing number of ferry operators are turning to battery power to address emissions and upgrade their fleets.

Washington State Ferries, the largest U.S. ferry system by ridership, plans to invest nearly $4 billion between now and 2040 to convert existing vessels or build new ones with hybrid-electric systems, which will be able to operate fully on battery power much of the time. In San Francisco, the Water Emergency Transportation Authority (WETA) has secured at least $117 million in local, state, and federal funding to help electrify its ferries and build out necessary charging infrastructure.

Still, hydrogen vessels like Sea Change could be a better option for ferries traveling long distances or for extended periods of time. Boosting battery capacity adds weight and slows down vessels. Hydrogen ferries also bring their fuel supply with them in storage tanks, obviating the need to build out high-voltage fast-charging stations.

Globally, a few dozen projects for testing hydrogen fuel-cell watercraft have launched since 2000, including the French research vessel Energy Observer. But Sea Change will be the first in the world to operate commercially.

Sea Change includes 360 kilowatts of fuel cells, a 600 kilowatt electric propulsion system, lithium-ion batteries, and 242 kilograms of hydrogen storage tanks. For now, the fuel cells will use conventional hydrogen, produced using fossil gas, which will come from existing automotive fueling stations in the San Francisco area, said Pace Ralli, CEO of Switch Maritime.

Ralli said the company is committed to operating the ferry and future vessels with green hydrogen — made using zero-carbon electricity and water through electrolysis — once supplies become more readily available. But procuring green hydrogen for Sea Change has been challenging, in part because the vessel uses relatively small volumes of hydrogen, meaning it does little to move the needle on hydrogen production.

Switch also only has a six-month lease agreement with San Francisco Bay Ferry, a public transit service administered by WETA. Ralli said that Switch can’t make longer-term supply-chain commitments to procure green hydrogen until it has a longer lease commitment to operate Sea Change.

“Without a doubt, development of a green hydrogen supply chain is imperative,” he told Canary Media by email. ​“We see ourselves as playing an integral role in building out the supply chain, and we are actively pursuing mechanisms to catalyze production of green hydrogen … to support our growing fleet of zero-emission vessels in the near term.”