In San Francisco, a Hydrogen-Powered Ferry

The world's first hydrogen-powered commercial passenger ferry will start operating on San Francisco Bay as part of plans to phase out diesel-powered vessels and reduce carbon emissions, per the AP. The 70-foot catamaran called the MV Sea Change will transport up to 75 passengers along the waterfront between Pier 41 and the downtown San Francisco ferry terminal starting July 19, officials said. The service will be free for six months while it's being run as part of a pilot program.

• Specs: Sea Change can travel about 300 nautical miles and operate for 16 hours before it needs to refuel. The fuel cells produce electricity by combining oxygen and hydrogen in an electrochemical reaction that emits water as a byproduct.
• Shipping: The technology could help clean up the shipping industry, which produces nearly 3% of the world's total greenhouse gas emissions, officials said. That's less than from cars, trucks, rail, or aviation but still a lot—and it's rising.
• Takeaway quote: "The implications for this are huge because this isn't its last stop," said Jim Wunderman, chair of the San Francisco Bay Area Water Emergency Transportation Authority, which runs commuter ferries across the bay. "If we can operate this successfully, there are going to be more of these vessels in our fleet and in other folks' fleets in the United States and we think in the world."
• Pros/cons: For now, the hydrogen produced globally each year, mainly for refineries and fertilizer manufacturing, is made using natural gas. A study out of Cornell and Stanford universities found that most hydrogen production emits carbon dioxide, which means that hydrogen-fueled transportation cannot yet be considered clean energy. Yet proponents of hydrogen-powered transportation say that in the long run, hydrogen production is destined to become more environmentally safe. They envision a growing use of electricity from wind and solar energy, which can separate hydrogen and oxygen in water. As such renewable forms of energy gain broader use, hydrogen production should become a cleaner and less expensive process.

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