Here’s the problem: gasoline is an incredibly efficient energy-storage medium that’s hard to beat with current technology. A gallon of gasoline packs 114,000 BTU, which is the caloric equivalent of about 43,000 Whoppers (without cheese, but with mayonnaise). This means the gas tank of a KLR650 contains enough energy to provide a nice lunch to a small city. That’s enough energy-storage capacity to ignore the inefficiencies of internal-combustion engines and drivetrains, where typically less than 20 percent of those burgers actually turn the back tire.
Electric-powered vehicles are much more efficient—somewhere in the 75 to 85 percent range, in fact. But the pathetic energy density of current battery technology is the weak point, even though huge strides have been made in the last decade. Still, judging from the feedback to our story on the new Zero motorcycles, a motorcycle with a 40-mile range (and a top speed of less than 70 mph) isn’t going to impress anyone. Even if that capability doubles in 10 years, it’s still not that appealing to those of us used to cruising at 80 mph and going 150 miles or more between our 5-minute fill-ups.
Hydrogen offers a solution. It’s the most abundant material in the universe, has three times the energy density of gasoline, and the most harmful pollutant emitted when it’s burned is steam (yes, I know it takes more energy to generate hydrogen than it stores). It can also power fuel cells to generate electricity, a proven (if expensive) technology that’s been in use for 50 years. The problem is that hydrogen is explosive (how was that trip to Lakehurst, Herr Zeppelin?) and must be stored and transported either at very high pressures or very low temperatures. That’s expensive to do, which means that hydrogen—in its current form—is a long way from being a practical fuel.
But what if you could somehow pack that hydrogen into a substance that could be stored and transported like regular unleaded? That’s exactly what U.K.-based Cella Energy says its new technology will allow. Through a new process called “coaxial electrospinning,” chemical hydrides (hydrogen-containing compounds) are trapped in a nano-porus polymer. No, I don’t have any idea what that means, either, except that the end result is micron-sized beads that can store hydrogen. Since the beads are so tiny (if you laid a million end to end they would stretch a bit over three feet) a large quantity has properties similar to water.
These beads could be stored in a plastic fuel tank in a vehicle, and then pumped into a “hot cell” where the hydrogen would then be used in a fuel cell, or in an internal-combustion engine. The empty nano-beads could then be stored in another tank for future disposal. The encapsulated hydrogen could also be somehow mixed with hydrocarbon fuel to boost its energy level and lower emissions.
Sound too good to be true? Well, actually, it is—at least for now. The ammonia-borane/polystyrene nano-scaffold Cella has been using to develop encapsulated hydrogen is “not currently a viable commercial material: it is expensive to make and cannot be easily re-hydrided or chemically recycled.”
But that doesn’t mean it won’t happen soon. “Better living through chemistry” is a cliché, but our modern civilization wouldn’t be remotely possible without the huge advances in chemical engineering we’ve seen in the last 150 years, advances that would seem like magic to a person from the 18th century. Will nanotechnology let us enjoy clean-burning, high-performing motorcycles guilt free? Or will we be stuck with the inoffensive hum of electric motors?