8 Things You Need To Know About Hydrogen Fuel-Cell Cars
Plug-Free Electric Vehicles Are on the Way
Hydrogen fuel-cell vehicles have been around a while, but their introduction to car shoppers has long been held back by a chicken-or-egg dilemma: A successful retail launch of fuel-cell electric cars and SUVs requires a retail fueling system. And when was the last time you saw a hydrogen station?
Well, fuel-cell vehicles — and the stations that will power them — are about to become part of the landscape, a mere 12 years after American Honda began leasing a handful of hand-built cars to the city of Los Angeles.
The cars and stations will be a limited presence at first, confined to select areas of Southern California. But if some of the world's major automakers and the U.S. and various state governments have anything to say about it, the stations ultimately will spread throughout the nation's urban areas.
The first fuel-cell vehicles entered the retail market this spring in California's Orange and Los Angeles counties, courtesy of South Korean automaker Hyundai. Following in 2015 will be offerings from Japan's Toyota and Honda. In 2017, General Motors and Mercedes-Benz are expected to enter the market. Ford, Nissan and Volkswagen also are developing electric-drive cars fueled by hydrogen gas.
Here's what you need to know about these cars and the safety of this unfamiliar fuel. The vehicles don't need gasoline. They aren't tied to an electric plug. They produce zero emissions from the tailpipe and can deliver 300 miles or more per tank of fuel. They can be refilled as fast — or faster — than a conventional car with a 15-gallon gas tank. After extensive testing, researchers say they are as safe to drive as gasoline cars.
1. What's the Secret of Fuel Cells?
"Hydrogen fuel-cell vehicle" sounds pretty exotic, but in reality it's just an electric car that replaces the bulky, heavy and expensive grid-charged battery pack with a relatively small, lightweight and expensive electrochemical system that produces electricity onboard.
The fuel cell is the system's power plant. In it, hydrogen gas drawn from an onboard pressurized tank reacts with a catalyst, typically made of platinum. The process strips the electrons from the hydrogen, freeing them to do their thing — which is to be the electricity that flows through the electric motor to power the car.
After their job is done, the electrons return to the fuel cell, where they are reunited with the parent hydrogen in the presence of oxygen pulled in from the ambient air. They meet in a ratio of two atoms of hydrogen to one of oxygen. Presto! It's H2O, or water. The water helps cool down the stack (all those excited molecules make a lot of heat) before it then dribbles out of the vehicle's tailpipe as a combination of steam and distilled water.
One fuel cell doesn't produce all that many electrons, so automakers bind scores of the flat, rectangular cells together into a fuel-cell stack to get enough juice to power a car or truck. The stack acts much like a battery, releasing electricity in a constant flow to power the vehicle's electric motor and auxiliary electronics.
Fuel-cell stacks typically are sized to produce just slightly more power than the vehicle can use under normal acceleration and cruising conditions. The excess, augmented by electricity from the vehicle's regenerative braking system, is stored in a small lithium-ion battery for use when the vehicle needs an extra burst of power.
Once the fuel-cell stack does its magic, the vehicle is just like any other electric-drive vehicle on the road, running in near silence with loads of acceleration, thanks to the electric motor's hefty torque output.
2. Where Do We Get the Hydrogen?
Hydrogen is the most common element on the planet, so there are no worries about shortages. It rarely exists as free hydrogen, however. It usually is bound to something else, like hydrogen in water or in natural gas.
We make plenty of hydrogen in the U.S, mostly by "reforming" natural gas to break down the molecules and split off their hydrogen atoms. And most of what we make is used in refining oil or manufacturing ammonia for the fertilizer industry.
Some hydrogen fuel for fuel-cell cars is pulled directly from a pipeline serving one of those oil refineries. It's near the Torrance, California, headquarters of both American Honda and Toyota Motor Sales U.S.A.
Some hydrogen is made on-site at a few fueling stations that use electrolysis to split the hydrogen molecules from water. The electricity for that process can come either from on-site solar panels or from the local electrical grid.
Most hydrogen for fuel, however, is made in large hydrogen processing plants, which are the same ones that serve the oil industry. The hydrogen is then trucked to the stations and stored in large above-ground tanks.
To make it into fuel for fuel-cell vehicles, the hydrogen must be compressed. The present standard is 10,000 pounds per square inch, which also is designated as 700 bars. It is then chilled to keep it from heating and expanding as it is pumped into the vehicle. That equipment is part of the fueling station.
A hydrogen fuel-cell vehicle's tank is sized in kilograms. A 4-kilogram hydrogen tank (8.8 pounds) holds the energy equivalent of 4 gallons of gasoline. Today's hydrogen fuel stations can fill such a tank in 3-5 minutes.
3. Is Hydrogen Fuel Safe?
The short answer is that hydrogen behaves differently from gasoline. But generally it is about as safe as the gasoline we now put in most vehicles' fuel tanks. In fact, the average gasoline tank holds three to four times the energy — and thus three to four times the explosive power — of the hydrogen tanks that the first fuel-cell electric vehicles will be using.
Hydrogen is the lightest of the elements, approximately 14 times lighter than air. So even though it is highly flammable, escaped hydrogen (burning or not) dissipates quickly and typically in a narrow column shooting straight up into the atmosphere.
Its vapors don't pool on the ground, as do gasoline's heavier-than-air vapors. So in most cases, hydrogen doesn't present as great a fire or explosive danger. To further minimize the potential for explosion, almost all hydrogen fuel stations store the gas above the ground in well-vented areas.
The University of California at Irvine has operated a public hydrogen station for a dozen years without incident, says Carl Baust, alternative energy projects specialist for the Orange County Fire Authority. Several other hydrogen stations opened in Southern California and the Sacramento area to fuel test the vehicles that have been plying the state's highways since 2002. So far, they also have been incident-free.
The vehicles themselves have arrays of hydrogen sensors that sound alarms and seal valves and fuel lines in case of a hydrogen leak. Additionally, the pressurized tanks that hold the hydrogen have been tested repeatedly and found to be safe in collisions.
One test involves firing live ammunition into the tanks to pierce them. Pierced tanks typically vent their hydrogen so quickly that even if the gas catches fire it is out of the tank before explosive pressure could build up.
In 2001, researchers at the University Of Miami's College of Engineering set fire to the hydrogen in a tank mounted in an SUV and later punctured the fuel line on a conventional gasoline-powered vehicle and set the leaking gas on fire. The burning hydrogen versus gasoline test showed that flames caused "severe" damage to the gasoline vehicle, whereas the hydrogen vehicle was undamaged because the burning hydrogen gas vented up and away from the vehicle.
4. What About the Hindenburg?
Hydrogen is scary to many Americans because of a horrific incident in 1937: A passenger-carrying German zeppelin named the Hindenburg burst into flames while landing in New Jersey during a lightning storm. The fire and resulting crash killed 36 people and dozens more were injured. Flames from the burning hydrogen that had provided lift for the zeppelin billowed into the night sky.
Or was it burning hydrogen? The gas has taken the blame for the Hindenburg disaster almost from Day One, but modern researchers have shown that the millions of cubic feet of highly flammable hydrogen pretty much burned up in less than 60 seconds.
The horrific smoke and flames caught by news cameras is now thought to have been largely from the diesel fuel that powered the aircraft's engines and the aluminum-powder-painted canvas "gas bag" that contained the hydrogen.
So yes, the Hindenburg's hydrogen was likely the villain that started the calamity, but just because it wasn't the safest thing to use to keep huge lighter-than-air ships aloft doesn't mean that it's not safe for use as a fuel in land-based vehicles.
5. Why Might I Be Interested in a Fuel-Cell Vehicle?
Automotive fuel cells are seen by many as the best bet for widespread replacement of internal combustion engines in the U.S. This is a country where cars and trucks tend to be big. Driving distances also tend to be longer than battery-electric cars can accommodate — or so many motorists think.
The argument for fuel-cell vehicles is pretty simple: A fuel-cell electric system isn't range-constrained like a battery-electric system. Fuel-cell vehicles aren't tethered to charging cords. They carry enough fuel for 250-350 miles of range and their tanks can be refilled as quickly as that of standard vehicles' gasoline tanks. Few think they will replace battery-electric cars, which can make a lot of sense for drivers with short commutes. But they are expected to become a significant part of the alternative-fuel fleet in coming years.
Typically, a fuel-cell system is twice as efficient as a gasoline system. Most of the fuel-cell vehicles coming to market in the next few years will be able to deliver close to 70 miles per kilogram of fuel. That's the equivalent of 70 miles per gallon. There is no established retail price for hydrogen fuel, but most suppliers say $10 per kilogram is about right for the early days of low-volume sales. The price is expected eventually to fall to parity with gasoline.
Additionally, fuel-cell systems are much lighter and smaller than the battery packs that dominate plug-in electric drive systems. That means they can be more easily scaled up without the weight penalties that make plug-in systems impractical for large sedans, SUVs and pickup trucks.
So while battery-electric vehicles tend to be compact and subcompact models with limited range and lengthy recharging times, fuel-cell electric vehicles are quick and easy to refuel. Fuel-cell systems could power everything from minicars to large pickups.
They also are true zero-emissions vehicles, as clean as battery-electric cars on the road. They are also almost as clean on a well-to-wheel basis, says Steve Ellis, American Honda's national fuel-cell marketing manager.
"When the hydrogen is made from natural gas, there are at least 60 percent fewer CO2 emissions on a well-to-wheels basis than from gasoline," he says. "Plus there's a one-to-one alignment with gasoline cars" in terms of range, convenience and, ultimately, the varieties of vehicles you'll be able to get.
"They are the only zero-emissions vehicle that allows a really meaningful impact" on air quality and oil consumption, says Craig Scott, Toyota's national manager of advanced technology vehicles.
6. What Will They Cost?
Carmakers don't like to disclose their costs, for competitive reasons among other things. But when Honda began testing its FCX Clarity fuel-cell sedan in 2008, most journalists called it a million-dollar car and the automaker didn't object.
Since then, though, the talk has mostly been about how much cost has been pared down as the fuel-cell technology has improved.
Hyundai said it has cut the cost of building its fuel-cell electric vehicle by 70 percent over the past decade. It expects the cost of fuel-cell cars to reach parity with the cost of similarly sized and equipped conventional cars by 2020.
The automaker is offering the 2015 Hyundai Tucson fuel-cell vehicle, a midsize crossover SUV, on a lease-only basis for $499 a month. The lease payment also covers all maintenance and fuel.
Toyota and Honda are saving financial details on their vehicles until they are closer to launch, but Toyota's Craig Scott said that the company typically offers its customers the choice of buying or leasing, as it has done with its various hybrids and the battery-electric RAV4 EV.
"We can't sell them in volume so we have to make them affordable," Scott says.
7. Will Vehicles Be Readily Available?
There may not be many fuel-cell cars at first. There weren't many gas-electric hybrids when Honda and then Toyota braved the U.S. marketplace with their initial offerings in 1999 and 2000, either. But the automakers and regional and national governments are betting billions of development and marketing dollars that the cars will catch on.
Initial availability will be in Southern California because that's where nine of the 11 public hydrogen stations in the country are located. There's a 10th station in Northern California, near San Jose, while the 11th is in South Carolina.
Hyundai began leasing its 2015 Tucson fuel-cell electric vehicle in June and offers it through just three Southern California dealerships: Hardin Hyundai in Anaheim, Tustin Hyundai in Tustin and Win Hyundai in Carson. Other dealers will follow if demand dictates.
Toyota and Honda haven't announced their initial dealerships yet, but likely will have more than three apiece given the size of their dealership networks.
8. Where Would I Get Fuel?
A small network of hydrogen fuel stations will support the slow rollout of the vehicles that drive like battery-powered electric cars but get their fuel from a pump rather than a plug.
There are only 10 public stations today in California, but 17 more are under construction. The state has a hydrogen fuel plan that will see 68 stations strategically located in California's Southern and Bay Area metropolitan regions by the end of 2017, with a goal of 100 stations by 2020.
Funding for construction, at an average of about $1.5 million per station, is being provided by grants from California's Alternative and Renewable Fuel and Vehicle Technology Program.
A study by researchers at UC Irvine looked at street-level census and land-planning data and picked locations for each of the initial 68 stations. Developers of the university's STREET hydrogen station plan say it will put a hydrogen station within a six-minute drive of 80 percent of the Californians who live in areas that, demographically, are those in which customers for fuel cells cars would most likely reside.
Beyond 2017, hydrogen backers plan for similar stations to be opened in other regions of the country that have proven themselves friendly to alternative-fuel vehicles. A private-public partnership called H2USA, formed in 2013 by the Department of Energy, is coordinating national plans.
The ultimate goal is a coast-to-coast and border-to-border network that will make owning and driving a fuel-cell vehicle as easy as owning and driving gasoline and diesel vehicles is today.