What is a Hydrogen vehicle?
A hydrogen vehicle is a vehicle that uses hydrogen as its onboard fuel for motive power. Hydrogen vehicles include hydrogen fueled space rockets, as well as automobiles and other transportation vehicles.
The power plants of such vehicles convert the chemical energy of hydrogen to mechanical energy either by burning hydrogen in an internal combustion engine, or by reacting hydrogen with oxygen in a fuel cell to run electric motors. Widespread use of hydrogen for fueling transportation is a key element of a proposed hydrogen economy.
Hydrogen fuel cell features
Hydrogen fuel cell vehicles combine the range and refueling of conventional cars with the recreational and environmental benefits of driving on electricity. Refueling a fuel cell vehicle is comparable to refueling a conventional car or truck; pressurized hydrogen is sold at hydrogen refueling stations, taking less than 10 minutes to fill current models. Some leases may cover the cost of refueling entirely. Once filled, the driving ranges of a fuel cell vehicle vary, but are similar to the ranges of gasoline or diesel-only vehicles (200-300 miles). Compared with battery-electric vehicles—which recharge their batteries by plugging in—the combination of fast, centralized refueling and longer driving ranges make fuel cells particularly appropriate for larger vehicles with long-distance requirements, or for drivers who lack plug-in access at home. Like other EVs, fuel cell cars and trucks can employ idle-off, which shuts down the fuel cell at stop signs or in traffic. In certain driving modes, regenerative braking is used to capture lost energy and charge the battery.
The hydrogen conundrum
The first problem with that rosy scenario is that hydrogen and oxygen love each other so much that free hydrogen doesn’t really exist in our atmosphere. It’s all been turned into the water that covers most of the planet. So before we can get that energy, we have to make some loose hydrogen to put into our hydrogen fuel cell. There are a lot of ways to get hydrogen, and some are wackier than others. In the 19th century, people used to drop iron filings into barrels of sulfuric acid. The reaction produced hydrogen gas, which they ducted into balloons to go up in the air. It works, but it’s really not feasible on a large scale, and there are literally barrels of toxic waste involved every time you use this method. Let’s call that one a non-starter.
Why you’ll see more hydrogen cars in the future
To really understand the hydrogen-powered car, you have to look at it in the bigger context of electric vehicles. A cardinal rule of alternative fuels is that there is not one single solution that will work in every case. Battery electric vehicles are likely to take a long time to recharge for the foreseeable future, and affordable electrics will have limited range. Hybrids and even plug-in hybrids still use fossil fuels at some level, but you can get into them and drive long distances with easy refueling. Hydrogen power bridges that gap, giving you a zero-emissions vehicle that you can refuel like a gasoline-powered car, provided there is a hydrogen station where you need it. Within that context, there’s a place for hydrogen-powered cars in our world.