More than 40 million Americans will travel at least 50 miles over the long July Fourth holiday, and tens of millions more will make shorter journeys, predicts the AAA, whether to the beach, a summer cottage or simply to share hot dogs and watch fireworks with family and friends.
It may be called Independence Day, but our reliance on the automobile underscores the fact that the nation is still heavily dependent on petroleum—with all the consequences that brings from economic and environmental standpoints. But an announcement in New York this week could be thought of as the energy equivalent of the Declaration of Independence.
At a joint news conference, General Motors and Honda announced an ambitious new joint venture that they hope will allow them to transform the fuel cell from a scientific curiosity to a mass-market reality by the end of the decade. Described by some experts as a "refillable battery," a fuel cell combines hydrogen and oxygen from the air to create a steady stream of current that can be used to run electric motors. The only thing steaming from a fuel-cell vehicle's tailpipe is water vapor.
The technology could take the country closer to "weaning ourselves off petroleum," according to Charlie Freese, GM's global director of fuel cell development.
Together, the two makers have about 200 prototype fuel-cell vehicles, or FCVs, undergoing field tests to see how they perform in day-to-day, real-world use. Other manufacturers, including Ford, BMW, Mercedes-Benz and Toyota are also experimenting with hydrogen propulsion.
Both Honda and Toyota hope to launch low-volume production of new FCVs by 2015, though American Honda CEO Tetsuo Iwamura stresses that anything close to mass market levels will likely not occur before the end of the decade—or later.
Fuel cells were initially developed over 100 years ago, but the first serious application occurred with the launch of the Apollo missions in the 1960s and early 1970s. During the Apollo flights, fuel cells provided electric power during the long trips to the moon. To make the technology viable under the hood of a car means bringing the size, weight and cost down by many orders of magnitude.
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And then there's the issue of creating a hydrogen infrastructure. Today, there are just 10 filling stations in California available to consumers and only a handful more in the rest of the United States. California regulators are studying measures that would add perhaps another 100 by decade's end, but considering there are tens of thousands of gasoline stations, that's not likely to encourage potential customers.
The hurdles facing hydrogen power are similar to those facing battery propulsion. Electric vehicles are still costly, offer limited range and require time to recharge—with relatively few public charging stations yet available. So, even while more plug-ins and pure battery-electric vehicles reach market every month, total demand is so far less than half of one percent of the overall U.S. automotive market.
The problem, cautions David Cole, chairman emeritus of the Center for Automotive Research in Ann Arbor, Mich., is that "there's no silver bullet," no single solution that can achieve the switch away from petroleum.
If there's no easy way to abandon petroleum entirely, can we at least declare partial independence?
Conventional hybrids, which recapture energy normally lost during braking and coasting, are perhaps the most immediate—if partial—solution. As costs come down, it becomes easier to justify the premium when considering the amount of fuel saved over the life of the vehicle. Yet even a decade after the introduction of the original Toyota Prius, hybrids make up less than 4 percent of the U.S. market.
Another alternative is diesel. So-called oil burners account for nearly half of the European market and typically deliver about 30 percent better mileage than comparable gasoline vehicles. Chrysler last week announced plans for a version of its full-size Ram 1500 pickup—the first light-duty diesel truck on the market. GM and Mazda both have new diesel passenger cars coming and almost a third of some Volkswagen models are being ordered with these high-mileage engines. But most Americans are still reluctant, and even with new models coming, diesel sales have yet to catch up with hybrids.
With the country literally floating on reservoirs of natural gas, CNG is another technology with plenty of proponents. But it, too, has its drawbacks—for one thing, you'll sacrifice much of your trunk space for the big storage tank this fuel requires. And there aren't many places to fill up on CNG, either, so this relatively clean fuel is likely to appeal to commercial and government fleets, such as the natural gas-powered buses that have popped up in many American cities.
One of the more intriguing alternatives under study by VW's Audi brand would use excess wind power, water and CO2 emissions to create synthetic natural gas—something could obviate the need for the controversial drilling process known as fracking.
But like virtually all alternatives to petroleum, it would be costly. And that, ultimately, is the real issue.
As Americans, we talk of independence but when we put a price tag on it—at least when it comes to fuel—we're not quite ready for a revolution. Ironically, the longer petroleum prices remain affordable, suggests CAR's Dr. Cole, the more difficult it will be to justify an energy declaration of independence.
—By Paul A. Eisenstein, NBC News contributor.