If you are in China and looking to ride a shared bike in the city, you might find something on the bike that looks a little different: a water-bottle-size hydrogen tank.
At least a dozen cities in China now have some kind of hydrogen-powered shared bikes for their residents. They offer an easier ride than traditional bikes and a safer energy source than lithium batteries. One Chinese company is betting that this will be the next big thing in public transportation, while others are riding on a national trend toward government policies that encourage the development of the hydrogen industry.
Yet the reception has been mixed. Riders have reported unsatisfactory experiences with current hydrogen bikes, and energy experts doubt whether it makes economic sense to replace e-bikes with hydrogen-powered ones. Even though hydrogen could be a great power source for long-distance transportation in the future, it may not be suitable for urban biking, a completely different task.
While there are companies in other countries that are working on hydrogen-powered bikes—and one French company already has a mature product—China stands out for putting these bikes to use as public transportation. Bike-sharing became hugely popular in the country during the 2010s tech boom. With support from deep-pocketed companies like Alibaba and Meituan, standardized, internet-connected shared bikes have filled urban streets since, sometimes resulting in incredible waste.
Youon, a Chinese company with over 1 million bikes on the streets of over 300 cities, is one of the main players in the bike-sharing industry. Facing fierce domestic competition, the company has chosen to differentiate its brand by investing in hydrogen bikes since 2018, with four models now available to buy or rent.
A hydrogen bike is not very different in concept from an e-bike. The difference is in whether the energy is stored in a lithium-ion battery or a hydrogen tank.
Each of Youon’s hydrogen bikes stores 20 grams of hydrogen in the form of metal powders, which can absorb and release the gas in a tank at low pressures (less than 10 bar). When the rider starts pedaling, the hydrogen is fed to a fuel cell under the seat, where a chemical reaction takes place to produce electricity. At its peak, a hydrogen bike can go as fast as 23 kilometers (14 miles) per hour. One tank of hydrogen lasts 40 to 60 kilometers (25 to 37 miles), and replacing the tank takes a few seconds.
Why hydrogen?
E-bikes have existed in China for a long time. According to the official figures, there are around 350 million in China today, and they are commonly used by everyday commuters and professional delivery workers.
However, many of China’s largest cities have shied away from commissioning e-bikes as part of the public transportation network or even banned them, because lithium batteries pose a fire risk. In 2023, Chinese fire departments received a total of 21,000 reports of e-bikes catching fire, a 17.4% increase from the previous year.
That created a supply vacuum for Youon. It’s positioned itself as a safer alternative thanks to its use of hydrogen. The hydrogen is stored in a low-pressure state, and if there’s any leak, it will dissipate quickly without causing an explosion, the company says on its website.
It’s a strategy that’s worked: These bikes have been more readily accepted by local governments. In 2022, Youon sold 2,000 of its hydrogen bikes to Lingang, a new high-tech district in Shanghai; in 2023, the company sold 500 hydrogen bikes to the Daxing district of Beijing. Today, its hydrogen bikes can be found in over six Chinese cities.
Youon has since doubled down on its investment in hydrogen. The company has launched a product that lets users generate hydrogen at home with solar power and water. It also worked with the local government of Jiangsu, where its headquarters are, to publish a set of industry standards covering safety requirements, hydrogen tanks, and more. “Hydrogen energy is also an essential pathway to achieving carbon neutrality,” said Sun Jisheng, the CEO of Youon, at an industry conference in June.
The problem
However, that’s about where the advantage of hydrogen bikes ends.
David Fishman, a China-based senior manager of the Lantou Group, an energy consultancy, says he struggles to see the advantage. “Maybe the safety angle is a relevant factor for someone who doesn’t like carrying around lithium-ion batteries and storing them in their house,” he says. Other than that, hydrogen bikes are less energy-efficient than battery-powered bikes, and it costs more to produce hydrogen in the first place.
The main advantage of hydrogen as an energy source is that it has much higher energy density, meaning a hydrogen tank with the same weight as a lithium battery would produce more energy and power the vehicles to go farther. However, that advantage only kicks in for trips over 800 kilometers, says Mark Z. Jacobson, a professor of civil and environmental engineering at Stanford University.
That means hydrogen is a more economical choice for long-distance transportation like ships, planes, and trucks. Bikes, however, are almost on the exact opposite end of the transportation spectrum. Few people would bike for long distances, let alone those who are only renting a public bike for a short time. For anything shorter than 800 km, battery-powered vehicles are more energy efficient, says Jacobson. He estimates that a battery-powered bike consumes only 40% of the energy of a hydrogen-powered equivalent and also takes up less space.
On top of that, the company’s hydrogen bikes have failed to impress many of the early adopters.
Gu, a resident of Lingang who only wishes to use his last name for this story, tells MIT Technology Review that he tried the bikes several times and they never felt effort-saving to him. Instead, the bike, along with the hydrogen tank and fuel-cell-powered motors, felt heavy and hard to maneuver. As a user, he has no idea whether the bike was running as expected or if the difficulty he encountered was due to its running out of hydrogen, although the company is supposed to block any bike with low hydrogen reserves from being unlocked.
Another common complaint is the inconvenience of finding and returning the bikes because there are only a limited number in the city and they have to be returned to specific locations for easy retrieval or tank replenishment.
“The bike has to be returned to a designated spot. But even if I put the bike at that very location, there’s GPS drifting, and I’d be charged a very high fee for them to move the bike,” Gu says.
On social media, hydrogen-bike users have complained a lot about similar experiences. Youon has found itself caught up in headlines at least a couple of times recently, with stories where users question whether their bikes are really useful for their daily commutes.
Youon didn’t respond to questions sent by MIT Technology Review.
The future of hydrogen bikes
Despite all these issues, there are at least half a dozen more companies in China working to launch hydrogen-powered shared bikes. These are often startups operating small-scale pilot projects in cities that have sizable hydrogen industries, like Foshan or Xiaoyi.
Many of these cities have even bigger plans—they are vying to become the hub of the hydrogen economy in China, which is increasingly betting on it as the future of clean energy.
This year, for the first time, hydrogen energy was mentioned in an annual official report from Beijing, which summarizes government work. The Chinese government said it vows to “accelerate the development of hydrogen energy … after enforcing the lead in smart, connected new energy vehicles.” The mention injected a boost of confidence into the hydrogen industry in China, which already produces more hydrogen every year than any other country.
Not all of this is good news for the environment. About 80% of hydrogen produced in China actually comes from burning coal or natural gas, and some of the fiercest government support for hydrogen comes from coal-mining cities looking to transition. While the country is moving in the direction of green hydrogen (hydrogen generated with renewable energy and water), the fuel will remain polluting for a long time.
When a technology is still in the early stages, finding the best use case for it is key. There are plenty of companies in China working on developing hydrogen-powered trucks and other long-distance forms of transportation, but considering the size of the bike-sharing market in the country, it’s no surprise that turning their attention to bikes seems like a profitable idea to some.
However, if there’s no way to dramatically improve the performance or economics of hydrogen bikes, it’s hard to imagine the current batch of experiments lasting for long. As companies move from piloting their new products to seeking adoption and profits, they will have some serious questions to answer.