The Case for the Hydrogen Truck

The hydrogen car lost.

Not long ago, it seemed like hydrogen fuel cells would power the next generation of climate change-fighting vehicles. Instead, batteries won the future. Americans now buy hundreds of thousands of electric vehicles each year, while only a couple of mass market hydrogen fuel cell cars can be found, and only in a select few places with enough hydrogen stations to make them driveable. The 20-year-old dream of a “hydrogen highway” across California never quite materialized, and hydrogen’s ascent toward becoming the fuel of the future remains stuck in limbo.

Yet hydrogen just keeps humming in the background. Researchers are not giving up but plugging away, trying to refine the chemistry of producing commercial hydrogen to make it better and cheaper. Most of the attention it attracts goes to how it might be put to use in heavy industry, but there are glimmers of potential in transportation as well. Advocates plan for hydrogen to be used in places where it makes more sense than a battery-electric vehicle, from warehouse forklifts up to semi trucks.

It may be that hydrogen is not, as it was once hyped, the answer to everything. But it’s going to pop up in more places than you might think.

Here is a hydrogen fuel cell refresher: Like a battery, a fuel cell has two electrodes — a negatively charged anode and a positively charged cathode — plus an electrolyte, the electrically conducting medium. Each atom of hydrogen contains a single proton and electron. When the fuel cell separates those two components, electrons travel one way to create a flow of electricity, while the protons go another way to be reunited with oxygen in the air to create water and heat. Given that those are the fuel cell’s only byproducts, it has the potential to be a very clean energy source (depending upon how the hydrogen itself was created).

Hydrogen’s other strength is that it’s a fuel, one that, compared to charging a battery, more closely resembles our pump-and-go experience of the gas station. But there is a flip side to that feature. If America wanted to become a hydrogen economy, a new nationwide hydrogen infrastructure of pipelines and substations would be needed to create and distribute the stuff all around the country, which is even more ambitious than the current movement to fill the country with high-speed EV chargers.

That’s why hydrogen projects have gone local. In Northern California, a group of Hyundai XCIENT Fuel Cell semis — which the company claims to be “the world's first mass-produced, heavy-duty truck powered by hydrogen” — are about to begin an experiment in green trucking backed by the University of California, Berkeley, the Center for Transportation and the Environment (CTE), and state agencies including the California Air Resources Board (CARB). Later this year, the NorCAL Zero project will see 30 hydrogen semis moving goods between the Port of Oakland and inland destinations such as Sacramento, Stockton, Modesto, and Fresno.

There are battery-powered big rigs on the way, including Tesla’s much-ballyhooed semi. But there are several reasons to be gung-ho for hydrogen, says P.J. Callahan, CTE’s project manager for the NorCal Zero project. Battery semis, when weighed down with a full load of cargo, would deliver only 150 to 200 miles of range, he says. Hyundai’s hydrogen trucks already promise at least twice that much, and Callahan expects fuel cell trucking to reach much higher as the technology develops.

“The ultimate kind of range goal that we expect for these types of trucks is between 700 miles and a thousand miles,” he says. “That's extremely challenging with battery electric.”

Fuel-cell semis can also carry more volume because there aren’t batteries eating up cubic feet of space that would otherwise go to cargo, Callahan says. Hydrogen also has the potential to deliver minimal refueling times that clock-conscious truckers are accustomed to. Eventually. With today’s technology, he says, it might take a half-hour to fill a semi with hydrogen, but that’s because existing systems are slow and conservative, built with small passenger vehicles like the Toyota Mirai in mind. With standardized equipment made for trucking, he says, fill-up times could drop to five to ten minutes.

There is still the issue of new hydrogen infrastructure. But running trucks on familiar paths between the Port of Oakland and popular inland destinations negates the need to build new refueling stations everywhere. “We are going to need a refueling network of stations, but … you can just be smarter about the way that we plan it,” Callahan says.

Plenty of other vehicles beyond big rigs have quietly turned to or experimented with hydrogen. Amazon now runs its small army of warehouse forklifts on fuel cells and has signed billion-dollar deals for the hydrogen supply. Establishing a green hydrogen pipeline for small uses like forklifts, as well as 800 heavy-duty trucks, is meant to help the company use hydrogen to meet its net-zero by 2040 goals.

Some U.S. cities run municipal buses on fuel cells. Hydrogen is considered a strong candidate to decarbonize the cargo shipping industry. Experiments have shown that it’s possible even to fly airplanes this way, though Hydrogen Airlines is a long way off.

Where hydrogen will continue to find a home depends a lot on how it will be made in the future. Nearly all the commercial hydrogen used in America today is created via the process called steam methane reformation, in which the methane in natural gas is subjected to high-temperature steam. The conversion creates free hydrogen but also the greenhouse gas carbon dioxide as a byproduct. That’s why scientists are racing to find ways to bring down the cost of green hydrogen solutions such as electrolyzers. They apply current to water to separate it into its component elements of hydrogen and oxygen, but they remain more expensive than current technology.

“It's a major goal of the state of California. It's a major goal of the federal government through the Department of Energy. Their hydrogen hub initiative wants to reduce the carbon impact of hydrogen and to get to green electrolyzed hydrogen from renewable resources so that there's no carbon involved in any part of the value chain,” Callahan says.

If such a goal could be achieved, hydrogen fuel could be used for a lot more than moving vehicles. For instance: One of the problems of a power grid running mostly on renewables is the need to store solar or wind energy when it’s available to use when it’s not. We could give old EV batteries a second life as energy storage for the grid, but it’s possible to imagine using liquid hydrogen to do the same job.

Perhaps the fuel of the future is still the fuel of the future.