The race is on. As society endeavors to rid itself of fossil fuels, the transportation sector stands to undergo dramatic changes in the coming years.
Already, electric vehicles (EVs) have shaken up the automobile market. Now they face a challenger as hydrogen vehicles are also catching on as a clean fuel alternative.
Are hydrogen-powered vehicles a realistic option? Will they replace EVs as the leading choice for consumers who don’t want an automobile that runs on fossil fuels?
Fuel Cell Basics—How an Electro-Chemical Reaction Can Power a Car
Most cars are powered by an internal combustion engine (ICE) that harnesses the power of small, controlled explosions to create forward momentum.
The explosions are created when gasoline is fed into the engine's internal combustion chambers, pressurized, and ignited. The energy created from these explosions propels pistons, which travel up and down a rod, transferring their energy to a drive shaft, which turns the wheels of the car.
In contrast, hydrogen-powered vehicles utilize a device known as a fuel cell. Hydrogen is contained in a tank in the form of a gas, but it is not ignited and consumed in the same way that gasoline is burned in an internal combustion engine.
Instead, a chemical reaction separates the molecules of the hydrogen gas in a fuel cell to create an electric current. This current provides the electricity to move the car in the same way that it does in a battery-operated car.
The fuel cell features three basic components. Hydrogen passes through an anode, which is a negatively charged entry point. Oxygen enters the system at the cathode, which is positively charged.
At the anode, a catalyst splits the hydrogen molecules into electrons and protons. The protons pass through the third component of the fuel cell, which is a porous electrolyte membrane. At the same time, the electrons are forced through a circuit, generating an electric current and excess heat.
At the cathode, the protons and electrons reunite and combine with oxygen to complete the circuit. The only byproducts of this process are water molecules and heat. This contrasts greatly with internal combustion engines, which produce exhaust gases—one of the primary causes of airborne pollutants and greenhouse gases.
What Is so Great About a Hydrogen Car?
Understanding the basic elements of a fuel cell gives a hint of the many advantages of hydrogen-powered cars.
First is the availability of its primary source of fuel. Hydrogen is the most abundant element in the universe, and it is just as plentiful on Earth.
As mentioned, it is also clean, producing only water and heat.
Fuel cell vehicles are also efficient, quiet and can travel long distances. According to Drive Clean California, a consumer's guide to clean cars provided by the California Air Resources Board, fuel cell cars can carry enough hydrogen fuel for 300–400 miles of range. That's 100–200 miles more range than most EVs and comparable to gasoline-powered cars.
Drive Clean California notes that fuel cell cars are much more efficient than gasoline-powered cars. They have longer range by a factor of two. However, they carry less fuel in the tank, so the actual range comes out to be about the same.
Also, like gasoline-powered cars, fuel cell vehicles can be refueled in about five minutes. That's another advantage over EVs, which charge up in about thirty minutes in only the fastest scenario. More commonly, EVs take several hours to recharge, depending on the vehicle and the charger.
Like any promising technology, fuel cell cars also have disadvantages. They are more complex to build than EVs, so fewer manufacturers have embraced the concept.
Hydrogen must be pressurized before it can be stored in a fuel cell, and it is a highly flammable element, so it must be stored properly to avoid combustion.
The high cost to build and purchase the cars and the lack of wide availability of hydrogen fuel have stood in the way of more production and growing consumer demand.
The high cost to build and purchase the cars and the lack of wide availability of hydrogen fuel have stood in the way of more production and growing consumer demand.
Another challenge for hydrogen-powered vehicles is the fuel’s production. While hydrogen is ubiquitous, it occurs only in combination with other elements, such as water, natural gas, petroleum, and coal.
Because of this unique characteristic, hydrogen can only be used for generating electricity after it is separated from the other element it is combined with.
The Many Colors of Hydrogen
The most cost-effective way to produce hydrogen on a large scale is to separate it from fossil fuels, such as natural gas, oil, and coal. But this process, which creates what is known as “grey hydrogen,” also emits harmful CO2—the very thing the transportation sector is trying to reduce in its effort to combat global warming.
Hydrogen can also be separated from natural gas through a process that involves steam separation. Known as “blue hydrogen,” this process still produces carbon emissions, but they are captured and stored before they can be released into the atmosphere.
Finally, there is “green hydrogen,” the cleanest option. This produces no harmful greenhouse gases because it separates hydrogen from water using renewable energy.
Green hydrogen is produced from a process called electrolysis, which works a lot like a fuel cell, only in reverse. It runs an electric current through water molecules and splits them into hydrogen and oxygen.
While it may seem that green power has solved the problem of producing hydrogen without generating harmful greenhouse gases, it faces challenges of availability and cost.
When the electricity is generated by renewable power, such as solar and wind, the entire cycle from start to finish is completely free of any carbon emissions (aside from the initial emissions required to produce solar and wind power).
While it may seem that green power has solved the problem of producing hydrogen without generating harmful greenhouse gases, it faces challenges of its own. It is a far-off goal to develop renewable generating capacity to support electrolysis on a scale large enough to fuel a global adoption of hydrogen fuel-cell cars. It would require an even greater rollout of renewable energy than is already needed to power the world's escalating demand for clean electricity, and the cost of doing so is equally daunting.
Another obstacle to widespread use of hydrogen is the lack of existing infrastructure.
Hydrogen must be either highly pressurized or liquified when it is transported. Furthermore, it is not as dense as gasoline, so the volume of hydrogen that is needed to fuel a mass market of fuel cell cars is much greater than the volume of gasoline needed for ICE cars.
For more cars to be able to run on hydrogen, the nation's existing storage and transportation infrastructure would have to be modified to accommodate the unique needs of this fuel.
At this point, the US does not have the pipelines, delivery, and storage systems to handle these needs on a macro scale.
Powering On
These challenges have not slowed the movement for hydrogen fuel-cell cars. The prospects and benefits are too good to overlook.
For example, American engineer, Mike Strizki, has built a home in Hopewell, New Jersey, that is completely off-grid and powered by a unique combination of solar, geothermal, and hydrogen energy. The latter is generated by an electrolyzer (through electrolysis) that is powered by his solar panels.
His home is not the only thing powered by hydrogen. Strizki boasts that his lawn mower, motorcycle, All Terrain Vehicle (ATV), and his customized fuel cell car are all fueled by hydrogen his home produces.
His car features two fuel cell stacks and an electric motor that was switched out of a bus. He tells a story about how he drove the car across the desert to Las Vegas and stopped along the way to drink the water that came out of his tailpipe.
According to Strizki, hydrogen technology is here and it’s ready. “This is not the future, this is now.”
He adds that great things are in store. “We are now at the very beginning of the learning curve of this technology,” he says.
Hydrogen Cars Are Coming to Market
At least two auto manufacturers are attempting to embrace hydrogen on a market scale.
Korean automaker Hyundai describes its fuel cell vehicle, the Nexo, as “the world’s first dedicated hydrogen-powered SUV.” According to the company, the car has an estimated range of up to 380 miles.
However, the manufacturer's suggested retail price (MSRP) is just over $60,000, which would not be considered affordable by the average car shopper.
Another option is the Toyota Mirai. It has relatively the same fuel efficiency and range, while having a starting price of $49,000.
Hydrogen cars have a lot of catching up to do if they are to compete with EVs.
According to Car and Driver Magazine, by mid-2022, less than 15,000 hydrogen-powered vehicles could be found on US roads, and virtually all of them were in California. In contrast, about 2.5 million EVs have been sold in the U.S.
While hydrogen isn't winning the competition against EVs in the open market, certain advantages may make it a favorite for certain specific types of travel. For example, long-haul trucks may be an ideal use for fuel cells because they won't have to stop as often to charge up. Garbage trucks are also a prime candidate for fuel cells because their frequent stopping and starting wears down an electric battery.
The best approach may be incremental. Just as hybrids helped introduce consumers gradually to EVs— think of the Toyota Prius—a similar concept may encourage the public to embrace hydrogen.
A vehicle that is powered both by an electric battery and a fuel cell will combine the best of both technologies, offering consumers a smooth transition to the technology while the supporting infrastructure is built out.
Last year, French carmaker, Renault, introduced just such a model with its electric-hydrogen hybrid concept car. The “Scenic Vision” incorporates a hydrogen engine, electric motor, battery, fuel cell, and hydrogen tank. The greatest advantage to this combination is its greatly extended range. Renault boasts that the fuel cell enables the car to drive nearly 500 miles before having to recharge the battery. That's about 200 miles more than either an all-electric or a gasoline-powered car.
The Future of Hydrogen
All options are on the table when it comes to fighting global warming. The potential of hydrogen has been recognized. Whether society, technology, and markets can combine to make it effective remains an unanswered question.
In the words of the hydrogen champion Mike Strizki, “A lot of new methods are going to come out in the next couple of years to make hydrogen cheaper and renewable, and that really is the holy grail.”
If he is correct, many future automobile purchases may just be a clean, new, hydrogen fuel-cell car.
*Richard Laezman is a freelance writer in Los Angeles, California. He has a passion for energy efficiency and innovation. He has been covering renewable power and other related subjects for more than ten years.
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