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That's the best case scenario, of course, assuming technology, government, industry and the public all cooperate on bringing hydrogen cars to the nation's highways.
"The use of hydrogen fuel cell vehicles can achieve large and sustained reductions in U.S. oil consumption and CO2 emissions, but several decades will be needed to realize these potential long-term benefits," says the NRC report.
Fuel cells combine hydrogen with a chemical catalyst to make electricity and water exhaust. In contrast, the nation's 235 million cars and light trucks burn about 44% of the country's oil and release about 20% of its industrial carbon dioxide emissions. All told, transportation represents about 5% of the U.S. contribution to global warming, but spikes in the price of gas have sharpened interest in alternatives to gasoline, such as biofuels and hydrogen.
In 2002, then-Energy Department chief Spencer Abraham unveiled the $1.2 billion FreedomCAR effort, which partnered DaimlerChrysler, Ford, General Motors and others in a research push for fuel cell cars. The CAR in FreedomCAR stands for "Cooperative Automotive Research" and the Freedom meant freedom from oil imports, greenhouse gas emissions and "Freedom for Americans to choose the kind of vehicle they want to drive, and to drive where they want, when they want," according to the Energy Department.
Congress asked the NRC to estimate how much that kind of freedom costs. Getting fuel cell cars out of the research lab and onto the road will take roughly $3.7 billion a year, the report estimates — mostly for $55 billion in total subsidies until the fuel cell become cost-competitive — from 2008 to 2023. The exhaustive 252-page report maps out a plan through research, subsidies and government polices to have two million hydrogen cars on the road, amid 280 million regular cars and trucks, by 2020. Fuel cell cars could represent 80% of the new cars on the road if the public buys into the plan.
Besides public acceptance, the plan relies on the government pulling off a graceful switch of gas stations to hydrogen stations through regulation and the requirement that much of the hydrogen be made with electricity generated by "sequestering" carbon dioxide emissions from burning coal in underground layers of rock. Burning coal to make electricity to make hydrogen would likely create more carbon dioxide emissions than just burning oil, so the whole thing relies on carbon sequestration, an unproven technology in electricity generation.
"If you can convert to hydrogen you can eventually get it down to zero on oil use," says the NRC's Alan Crane, who led the study. "And you won't get there unless you start. So, if you keep pushing off the start mechanism, you won't get there." He notes that current subsidies for ethanol, $2.3 billion a year estimated to grow to $15 billion a year by 2020, dwarf the report's proposal for hydrogen cars.
Most industrial hydrogen today comes from blasting natural gas with steam, a process that also releases carbon dioxide. A Penn State team last week proposed using solar energy-powered nanotubes to split water into hydrogen and oxygen, a process called electrolysis, in the journal Nano Letters, but such ideas remain experimental for now.
The big surprise for the study authors, says Crane, was how much technological progress has occurred since 2002 in making fuel cells more efficient, longer-lived and more durable. The last technological hurdle is storing hydrogen in a car, he says, where current technologies pressurize the gas up to 10,000 pound-per-square-inch, something that takes a lot of energy. Remember the Hindenburg? Crane says past studies have found that safety isn't a big concern with hydrogen as a fuel, despite its fearsome reputation. "Gasoline has a lot of problems too," he says. "Hydrogen dissipates, it doesn't pool under your car and combust."
The report concludes by calling for government research into all sorts of alternative-fuel technologies to cover its bets. A mixture of energy efficiency, biofuels and eventually, hydrogen, could lead to fuel cell cars going from $100,000 vehicles today to the affordable ride of tomorrow.
http://www.usatoday.com
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