America’s first hydrogen-powered ferry is set to sail

America’s first hydrogen-fueled ferry is set to launch in San Francisco early next year after more than five years in development. As the milestone nears, the vessel’s owner says it’s already looking to deploy more zero-emissions ferries nationwide — particularly in places where aging, polluting diesel boats still ply rivers, sounds and coastlines.

On Thursday, the startup Switch Maritime said it raised $10 million in Series A funding to expand its one-vessel fleet. Nexus Development Capital led the round, which the investor described as ​“catalytic capital” meant to help Switch move beyond its first pilot project to become a full-on ferry-building business.

“A lot of municipal ferry operators in populated cities are under pressure to decarbonize, as are most transit systems,” Pace Ralli, Switch’s CEO, told Canary Media. ​“The technology exists; now it’s just about learning how to adopt these new decarbonized technologies and getting them to scale.”

Switch’s 75-passenger ferry, called Sea Change, is primarily driven by fuel cells, which combine hydrogen and oxygen to produce electricity and power electric motors. Unlike diesel engines, the fuel cells don’t directly emit carbon dioxide or toxic air pollution, just a little heat and water vapor. A 100-kilowatt-hour lithium-ion battery rounds out the ferry’s power system.

The fuel cells will initially use conventional hydrogen, which today is produced from fossil gas via emissions-intensive methods. Ralli said the goal is to shift to using only ​“green hydrogen” — made with carbon-free electricity and water — as soon as supplies become sufficiently available in San Francisco and beyond.

Another company, Zero Emission Industries, built the Sea Change’s hydrogen fuel-cell system and spearheaded the ferry’s early development. In separate news this week, ZEI said it closed a $8.75 million Series A financing round to advance its novel hydrogen refueling technology for maritime and heavy-duty vehicles.

Across the country, nearly 800 ferries zip over waterways carrying passengers and cars. Many of the vessels rely on decades-old, inefficient diesel engines, making them some of the largest emitters among commercial harbor craft. Typically, ferries operate around densely populated and marginalized communities, exposing people to health-harming pollutants such as particulate matter (PM) and nitrogen oxide (NO_x) emissions.

In California, where ferries represent only 2 percent of commercial harbor craft, the vessels emit 11 percent of total PM_2.5 emissions and 15 percent of total NO_x emissions within the maritime category, according to the California Air Resources Board (CARB). Last year, the regulatory agency adopted a rule requiring all short-run ferries in the state to be zero-emissions by the end of 2025.

“Focusing on developing zero-emissions ferries is literally a matter of life and death,” Grace Healy, interim senior director of Pacific Environment’s climate campaign, said by email. She noted that CARB has estimated that slashing emissions from ferries, tugboats and workboats would protect 9.7 million Californians from elevated levels of air pollution.

“Frontline Black and brown communities have been bearing the brunt of pollution for far too long, and moving to zero-emissions ferries would clear the air for port neighbors,” Healy said.

Hydrogen for ferries gains traction, but batteries are taking off

As ferry operators in California and other states begin transitioning away from diesel engines, some are turning not to hydrogen but to battery power — a technology that is already being deployed domestically in small recreational vessels and in ferries internationally.

Washington State Ferries, the largest U.S. ferry system by ridership, recently began retrofitting the first of three diesel ferries with hybrid-electric systems, which will be able to operate fully on battery power much of the time, Axios recently reported. The ferry system expects to bring its first fully electric ferry online in 2027, connecting Seattle and Bainbridge Island.

Outside the U.S., in Norway, more than 50 battery-powered ferries now ply the country’s abundant waterways, where ship operators face tight restrictions on CO₂ emissions and air pollution. The Bastø Electric, the world’s largest all-electric passenger and car ferry, can carry more than 600 people across the Oslo Fjord.

When it comes to choosing a zero-emissions technology — batteries or hydrogen fuel cells — Ralli said that Switch is ​“agnostic.” The company will help develop and deploy whichever technology best suits its future customers, including, potentially, municipal ferry operators and public transit agencies.

“Based on our experience in the space, there is no silver bullet,” he said. ​“There are going to be great routes that work on batteries, and there are going to be other ones that are very hard to take on batteries because of range issues.”

Operating ferries over long routes is challenging with batteries alone. Boosting onboard battery capacity not only adds weight, which slows down the vessel, but also takes up space, reducing the number of people and vehicles that can ride the ferry. To recharge, electric ferries need big jolts of power delivered relatively quickly, which can require extensive and expensive upgrades to electricity systems at ports and ferry terminals.

Hydrogen vessels, by contrast, can generally travel farther for longer stretches of time, in large part because they bring their hydrogen supply with them in storage tanks. Worldwide, more than 30 projects for testing hydrogen fuel-cell watercraft have launched since 2000 — though no hydrogen passenger ferries have been deployed commercially anywhere to date.

A hydrogen-ferry vision that’s been years in the making 

The idea to build the Sea Change came from an extensive 2016 study by Sandia National Laboratories, which found that a high-speed passenger ferry powered by hydrogen fuel cells was technically and economically feasible. Joseph Pratt, who co-authored the study, later sought to turn his research into a reality in the San Francisco Bay and launched the company Golden Gate Zero Emission Marine, which is now called Zero Emission Industries.

In 2018, CARB awarded a $3 million grant for the ferry demonstration, which was initially named Water-Go-Round. The project raised an additional $11 million in matching funds from partners including ZEI, Switch Maritime, Sandia National Laboratories, BAE Systems, Cummins and Port of San Francisco.

Switch bought Sea Change from ZEI in March 2020, and the newly built vessel first hit the water in 2021 at a shipyard in Bellingham, Washington. The ferry includes 360 kilowatts of fuel cells, 242 kilograms of hydrogen storage tanks and a 600-kilowatt electric propulsion system, along with the lithium-ion batteries. Sea Change can travel up to 300 nautical miles at speeds as fast as 15 knots, similar to the capabilities of diesel-powered vessels, according to Switch.

Since its completion, however, pandemic-related delays and extended permitting timelines have slowed the ferry’s rollout. Last March, the Sea Change was finally towed down to Pier 9 in San Francisco, where the vessel will operate as part of the public San Francisco Bay Ferry fleet administered by the Water Emergency Transportation Authority. Switch and WETA are currently working with the U.S. Coast Guard to get the vessel certified for operation, which was initially slated to start in August.

Ralli said he now expects Sea Change to begin running ​“very early next quarter” in 2024. Seamus Murphy, WETA’s executive director, said the agency continues to work with its partners to launch operations ​“in the coming months.” The hydrogen ferry is part of WETA’s larger effort to shift 50 percent of its vessel fleet to zero-emissions technologies by 2035, including a $15 million initiative to fund a battery-electric vessel and shoreside charging infrastructure.

“The future of maritime is zero-emission, and this is an exciting pilot we’re eager to see deployed,” Murphy said of Sea Change.