Designing an electric cargo ship isn’t as easy as making an electric car—and until recently, most experts would have argued that battery-electric ships weren’t feasible for traveling across oceans. A giant cargo ship might theoretically need a battery that weighs 1.6 billion pounds, more than the ship could carry. But one startup plans to soon begin crossing the Pacific with smaller electric ships that swap batteries at ports along the way, in a system that it says could prove cheaper than shipping with fossil fuels.
“We started with the problem of decarbonizing ocean freight, and finding a way to make it not cost more,” says Steven Henderson, cofounder and CEO of the startup, called Fleetzero, part of the most recent cohort at the tech accelerator Y Combinator. Henderson and cofounder Michael Carter both worked in the shipping industry and saw that there was a major challenge with the industry’s goals to cut emissions: The existing alternatives were far more expensive than the status quo. Ammonia or green hydrogen power, for example, could cost as much as four times more than the heavy fuel oil that ships use today. Engines also had to be redesigned to burn alternative liquid fuels, adding to the cost. “We realized that this isn’t good for the industry if this is our future, and not good for the world if rates go up,” says Carter. The company’s new approach means that customers will see no change to their freight costs.
[Image: courtesy Fleetzero]
They started exploring a range of alternatives, and initially thought that electric ships wouldn’t work. A container ship with room for 10,000 or 20,000 shipping containers, designed to circumnavigate the globe on a single tank of fuel, wouldn’t have the room for batteries, which don’t have the energy density of liquid fuel. “It wasn’t viable,” says Carter. “But we realized we were solving the wrong problem.” They calculated that if ships were smaller—their new design will have space for between 3,000 and 4,000 containers—and made quick stops along the way, current battery technology could make sense. “Modern ships are optimized around fossil fuels,” Henderson says. “What would it look like if you optimized ships around batteries?”
The company’s batteries are designed to fit into standard shipping containers, so a crane can lift them off the ship at a port and replace them with batteries that have been freshly charged. (Many ports don’t have the capacity to plug ships into power directly, and swapping batteries is also faster, although a Norwegian company is now testing a much smaller electric cargo ship that will make short journeys and plug in to charge.) On a typical route now, a ship traveling from China to the U.S. might pass by Japan and Alaska before reaching Seattle, and then travel down the West Coast to L.A.; the distance between ports is short enough that current battery technology can cover the range.
Because the ships are smaller, they can also stop at ports that aren’t commonly used today—as cargo ships have become oversized, only a small number of ports can handle them. Having more options means that the company will be able to avoid the crowded ports in situations like the recent delays in L.A. and Long Beach, where dozens of ships waited in long lines for days to unload. As a U.S.-based company, Fleetzero can also access some ports that foreign companies aren’t allowed to, making it possible to deliver goods more directly to customers.
[Image: courtesy Fleetzero]
“We can have a route between, say, Long Beach [California] and Portland [Oregon] on a ship, and effectively take thousands of trucks off the road,” says Henderson. “And it’s a cheaper service. Over-the-road shipping is quite a bit more expensive than ocean freight.” Right now, he says, if shoes made in China are delivered to Portland, Oregon, they might come on a ship that sails down the West Coast to Southern California, passing by Oregon. Then they might be loaded on a truck and travel back north, adding to the carbon footprint.
[Image: courtesy Fleetzero]
While the batteries will take up space on a ship, Fleetzero calculated that they will occupy less space than the current system with diesel engines and fuel and ballast tanks, leaving more room for cargo. Workers can charge batteries when the cost of electricity is low, and the batteries could also double as backup power for ships at California ports, where regulations are beginning to require ships to stop running their engines when they dock to cut pollution.
The startup has built one prototype shipping container-size battery so far, and will complete another in the next two weeks. It has also passed the first regulatory hurdle for safety standards at the American Bureau for Shipping. Next will come tests in a retrofitted ship, and the company is likely to begin operating its first ship in 2023. (Diesel-electric ships can be retrofitted within a couple of weeks, though Fleetzero plans to eventually build its own vessels, which will open up cargo space without the fossil fuel infrastructure on board.)
Several major companies are interested in using the ships for deliveries, from apparel and consumer electronics brands to big box retailers, the company says, with partnerships to be announced later this year. Companies including Amazon, Ikea, and Patagonia have goals to move to zero-carbon shipping by 2040. It’s feasible that all of that could happen with electric cargo ships, Henderson argues, though the battery technology is likely to evolve. “What we’re convinced of today is that the future of shipping is electric,” he says. “How those electrons are stored on the vessel, I think, will change over time.”