Hydrogen is the most abundant molecule on earth. In a fuel cell, it can power an electric motor with zero emissions. But Hydrogen has thus far not been considered a popular option for zero-emissions school buses, and the companies Hyperion and Pegasus Specialty Vehicles are hoping to change that perspective.
As Hyperion CEO Angelo Kafantaris tells it, hydrogen is a way to avoid the pitfalls of battery-electric school buses — including limited range and the finite recharging lifecycles of batteries — at a similar cost.
Hyperion and Pegasus are launching a partnership to produce hydrogen fuel-cell buses with the Zeus Electric Chassis, and they are hoping their joint venture will eventually see hydrogen school buses spreading across Pegasus’s home state of Ohio and then across the country. They aim to finish a prototype this year and begin production in 2024.
Last year, Pegasus opened a factory in Dunkirk, Ohio to manufacture components for diesel, gasoline and electric buses. It plans to add chassis and drive trains for hydrogen buses to the mix. Hydrogen “is just one part of it, but it’s going to be a big part, we feel,” said Pegasus President Brian Barrington.
Hyperion is a California- and Ohio-based company that makes hydrogen fuel cells and hydrogen storage while developing more efficient hydrogen delivery and storage technologies that increase vehicles’ range, explained Kafantaris. It also produced the prototype XP-1 hydrogen fuel-cell hypercar that can get 1,000 mpg-e and can go zero to 60 mph in 2.25 seconds.
Barrington said he became fascinated with the concept of hydrogen fuel cells after realizing the shortcomings in battery-electric buses, including batteries not working well in severe heat or cold, and concerns about long-term battery life.
“Batteries are built to be used sparingly over time When you use them top to bottom, they go bad very quickly,” said Kafantaris. “A tertiary issue comes when folks want to have a fleet of battery-electric, and you need more buses in your fleet. Now you need more power to power the buses…and a substation needs to be installed…That takes a lot of time waiting on the utility. It can take two years or more. When you calculate having to upgrade your refueling grid plus time delays, hydrogen makes more sense.”
Barrington said that while battery-electric buses may be ideal for daily school bus routes, especially in urban areas, field trips and far-flung rural routes can be challenging or impossible, especially when they only have a 120-mile range under the most optimum operating conditions.
“If you start climbing mountains, if you start getting into more rural areas, if the school in Dayton has to go to Cleveland for a basketball tournament over the weekend, you can’t do that with [battery] electric vehicles,” Barrington said.
But a hydrogen-fuel-cell bus could achieve a range of 500 miles or more on one tank, with the fuel cell lasting over 10 years, Kafantaris said.
Elusive Yet Everywhere
A hydrogen fuel-cell vehicle stores compressed hydrogen gas or liquid hydrogen in a tank and combines that hydrogen with oxygen from the air in a chemical reaction that powers a motor nearly identical to the motors powered by batteries in battery-electric vehicles. The only emissions from the reaction are water vapor and heat.
But even though hydrogen is ever-present in the atmosphere, obtaining pure hydrogen is a challenge. Decades after hydrogen fuel cell vehicles were created, fueling stations are still few and far between. A map from the Alternative Fuels Data Center shows 55 public hydrogen fueling stations in the U.S., almost all in California.
Proponents expect hydrogen production and fueling availability to grow thanks to government support and increasing incentives and mandates for emissions reductions.
Zero-emissions vehicle incentives on federal and state levels generally apply to hydrogen fuel cells as well as battery-electric, and the U.S. Department of Energy is prioritizing hydrogen production and distribution by spending up to $7 billion on up to 10 clean hydrogen hubs around the country. These hubs are meant for industrial processes, not transportation. Still, experts say the investment will likely benefit the hydrogen economy as a whole.
Hydrogen fuel cells are increasingly considered an important option for long-haul vehicles like semi-trucks and locomotives, since hydrogen offers a much longer range and faster refueling than battery electric.
A handful of public transit agencies have added hydrogen buses to their fleets, including Foothill Transit in Los Angeles County, where leaders see hydrogen as crucial to meeting their goal of zero emissions fleetwide by 2040.
Foothill Transit put its first hydrogen fuel-cell buses on the road last year, and it now has 33 ready to serve the county that sprawls over more than 300 square miles. The buses, made by Canadian company New Flyer, have 30-kilogram tanks for liquid hydrogen, and a 25,000-gallon fueling tank is being installed at the bus yard.
The first route to get a hydrogen bus was “a heavy use line, a local route that also serves a hospital, library, school, another medical center,” said Foothill spokesperson Felicia Friesema. “We wanted to test it and put it through its paces. Hydrogen fuel cell buses refuel in 10 minutes, and the range is 300 miles-plus, as opposed to the 150 we were looking at with battery-electric buses. Those two things alone meant it was a much more compatible vehicle in terms of the bread and butter of our services, to get people safely from point A to point B.”
There Are Skeptics
Some transportation experts and district leaders on the forefront of zero-emissions and alternative fuels buses said they do not see hydrogen as a viable option for school buses, or they have never even considered it.
Meanwhile, Ewan Pritchard, a consulting engineer specializing in transportation who will facilitate a session on the challenges of school bus electrification at STN EXPO Reno in July, said he does not think hydrogen is a viable choice for this industry.
“If it’s hard to electrify [with batteries], hydrogen makes sense,” he said, pointing to freight and aviation. “But the school bus is the easiest of all heavy-duty vehicles to electrify. The real push for hydrogen is in long-haul trucking. There is not a whole lot of cycle time where [a truck is] down and not being used. Those things will drive 400 to 500 miles, then you stop for 15 to 20 minutes, and keep on moving again. … Most school buses are under 100 miles [a day].”
Pritchard admits he has an “engineer’s bias” when it comes to battery electric versus fuel cells, as he said he believes the former is more efficient and less costly.
“A fuel cell uses a membrane to port electrons from one side to the other. That membrane will foul over time,” he said. “The life of those membranes is up for debate, whether you’ll get 2 years or 8 or 10 out of it and need to replace it. That’s analogous to having to replace the batteries in an electric vehicle.”
Pritchard also said that installing hydrogen fueling stations can be very expensive, and the faster a station fuels, the more electricity it typically needs to compress gas quickly. Depending on the local generation mix, that electricity may not be clean.
“It’s a bit of a shell game that goes on with hydrogen, where individual pieces of the puzzle can look really great, but if you take it in totality, it’s not as great,” said Pritchard.
Fueling and Safety
Districts or bus providers hoping to run hydrogen school buses would need a fueling station at their home base, and in the future hydrogen fueling stations could be available along highways, Kafantaris said.
Hyperion will offer “green hydrogen” fuel delivery to stations that it would build for clients on-site, starting in Ohio. Green hydrogen is created by using electrolysis to split water into oxygen and pure hydrogen, with the electricity used for the process coming from zero-emissions sources like wind and solar. Hydrogen is more commonly produced by splitting apart molecules of methane gas, which creates carbon emissions that can be released – meaning the process is not zero-emissions – or stored. In future stages, Hyperion plans to help build stations where on-site clean energy is used to produce hydrogen, so delivery is not needed.
Safety concerns about hydrogen fuel cells have also been raised since they often entail carrying compressed hydrogen on the vehicle. But hydrogen proponents say there are no safety issues, especially compared to gasoline and diesel.
Kafantaris said carbon-fiber hydrogen fuel tanks are literally bulletproof. “These tanks go through bonfire tests, drop tests, you can shoot them over and over with a high-powered rifle. They do not burst,” he said. “It’s safer than gasoline, which has a tendency to leak and catch other things on fire.”
If a leak were to happen, “hydrogen goes up in the air at 45 miles per hour, out of the way of anything combustible,” Kafantaris said.
So far, Barrington and Kafantaris said they have received an enthusiastic response from school districts and other potential customers in various states, though they declined to provide specifics.
“It’s just a matter of getting it out and proving that it’s real,” Barrington said. “This is very much a touch-and-feel market. We think that [providing examples is] all it will take. We initially said this is a game changer. Now it’s become a game wrecker.”
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