PHOTOS BY MITCH JACOBY
FACING OFF DOE hydrogen program manager Chalk (left) argues in favor of accelerating the pace of hydrogen research today, while Romm, author of "The Hype about Hydrogen," contends that advanced hybrids should be today's top priority and hydrogen cars should be moved to the back burner.
In terms of atomic size and structure, hydrogen stands out as small and simple. Yet discussion of hydrogen's possible future role as a primary energy carrier sparks debates that are big and complicated.
For years, some scientists and policymakers have argued that replacing petroleum-based fuels with hydrogen in a so-called future hydrogen economy would be an ideal solution to numerous energy-related problems. For example, using hydrogen as the
fuel in stationary and automobile-based fuel cells would cut down on pollution, they say, because fuel cells running on hydrogen generate electricity and water but produce virtually zero pollutants. Switching to hydrogen as the primary fuel also would lessen the growing U.S. dependence on foreign oil, proponents argue.
The case in favor of hydrogen has been made in academic circles for years. In 2003, President George W. Bush gave the idea of the hydrogen economy a shot in the arm and boosted public awareness by announcing the launch of a $1.2 billion hydrogen research initiative. Now, as the price of crude oil exceeds $60 per barrel and prices at the gasoline pump approach $3.00 per gal in some states, arguments in favor of hydrogen can be heard loud and clear.
But critics point out that the overwhelming majority of hydrogen prepared industrially--more than 90%--is made from fossil fuel sources such as natural gas via reforming processes that produce carbon dioxide and other greenhouse gases. And although hydrogen can be produced renewably--for example, by using wind- or solar-cell-generated electricity to electrolyze water--those processes are expensive.
In addition, critics contend that even if pollution and petroleum dependence are taken out of the equation, questions remain concerning the safety of hydrogen use by large numbers of motorists. Critics also stress that a storage and distribution infrastructure similar to the one in place today for automotive fuels will need to be designed, built, and tested before it can be used to supply a nation with hydrogen.
Furthermore, technology for carrying an adequate supply of hydrogen compactly on board an automobile will need to be invented to provide motorists with an acceptable driving range between hydrogen fill-ups (see page 42).
In this C&EN special feature, two energy experts face off on questions of research prioritization and hydrogen's role in future energy security. Arguing in favor of hydrogen is Steven G. Chalk, manager of the Department of Energy's Hydrogen, Fuel Cells & Infrastructure Technologies Program. Chalk is responsible for planning and implementing President Bush's Hydrogen Fuel Initiative and previously held other positions at DOE.
Joseph J. Romm, author of "The Hype about Hydrogen: Fact and Fiction in the Race to Save the Climate," argues that research effort and investment today should focus on technologies for hybrid automobiles, which are powered by both gasoline and batteries, not hydrogen-powered vehicles. Romm contends that hydrogen cars won't be available for years or make a significant environmental impact for decades. Romm was acting assistant secretary of energy and held various positions at DOE during the Clinton Administration. He serves as executive director of the Center for Energy & Climate Solutions.
Business-as-usual approaches have not reversed and cannot reverse our increasing dependence on imported oil. Since the oil crisis of 1973, oil imports have grown from about 35% of total U.S. consumption to over 55%. This dependence is caused primarily by the transportation sector's growing demand and overwhelming reliance on petroleum. In fact, by 2025 imports are projected to be 68%, threatening both energy security and economic stability. The Hydrogen Fuel Initiative addresses our long-term dependence on imported oil while reducing emissions of pollutants and greenhouse gases. A recent National Academies report supports this concept and concludes, "A transition to hydrogen as a major fuel in the next 50 years could fundamentally transform the U.S. energy system, creating opportunities to increase energy security through the use of a variety of domestic energy sources for hydrogen production while reducing environmental impacts, including atmospheric CO2 emissions and pollutants."
The Department of Energy's plan shows that it will take decades to fully realize the benefits of hydrogen. Therefore, DOE is continuing to develop high-efficiency technologies for near-term hybrid vehicles. The DOE FreedomCAR Program is investing over $90 million per year to make hybrid batteries, electronics, and materials more affordable. Hybrids are emerging in today's market and will provide the best approach for reducing petroleum consumption over the next 20 years. But efficiency alone will not enable our transportation sector, which accounts for two-thirds of our oil use, to eliminate its dependence on oil. Dramatically improved efficiency can slow the growth in transportation energy demand, but after a while the increase in population, the number of vehicles, and the miles of travel will cause oil demand to resume its upward trend. Therefore, fuel substitution must accompany fuel efficiency to achieve long-term energy security.
As a substitute for gasoline or diesel, hydrogen provides a long-term solution because it can be made from diverse domestic resources. Like electricity, hydrogen is an energy carrier that can be produced from renewable, nuclear, and fossil resources. Furthermore, hydrogen fuel-cell vehicles have no emissions; they produce only water.
DOE is not advocating a rush to deploy fuel-cell vehicles and hydrogen-refueling stations. In partnership with auto and energy companies, DOE has established a focused research plan that identifies the technical and economic goals to measure progress and to enable industry to meet customer requirements and establish a business case. The DOE program brings together leading scientists and engineers from hundreds of institutions--including university, industry, and government laboratories--to address the key challenges. These technical and economic challenges are formidable but not insurmountable:
- Improving hydrogen storage energy density by a factor of three, allowing a vehicle range of greater than 300 miles.
- Increasing fuel-cell durability fivefold and lowering cost from $200 per kW (today's projected high-volume cost) to less than $50 per kW.
- Reducing hydrogen cost by a factor of four to be competitive with gasoline.
DOE is also addressing hydrogen safety. Like other fuels, hydrogen can be used safely with appropriate engineering and handling. In fact, industry produces over 9 million tons of hydrogen annually and safely operates hundreds of miles of hydrogen pipelines. To ensure safe commercial use of hydrogen, DOE's program includes underlying safety research leading to new materials and components and new practices and building codes.
Unlike previous alternative fuel vehicle programs, this initiative includes neither quotas nor sales targets; criteria for the commercialization decision are market driven. If successful, the Hydrogen Fuel Initiative will facilitate a 2015 decision on commercialization. With subsequent investment in vehicle manufacturing and refueling infrastructure, hydrogen fuel-cell vehicles could enter the market in the 2020 time frame. Replacing the existing vehicle fleet takes time; therefore, significant energy and emissions benefits will occur after 2030. However, the DOE strategy of developing advanced hybrid vehicle technologies enables the country to begin the transition to hydrogen and fuel-cell vehicles while achieving petroleum savings and emissions reduction in the near term.
Transforming to a hydrogen-based transportation system is synergistic with reducing greenhouse gas emissions in the power sector. Because the total amount of energy required for the transportation sector rivals that for electricity generation, increased hydrogen demand can stimulate the expansion of carbon-free renewable and nuclear power. The U.S. is investing more than any other country in carbon capture and sequestration technologies, enabling virtually carbon-free hydrogen and electricity from America's abundant fossil resources such as coal.
The U.S. government is not alone in making hydrogen energy development a priority. Automotive and energy industries have partnered with the government and are making substantial investments--an unprecedented partnership in the history of technology development. In addition, 15 countries and the European Commission (the administrative arm of the European Union) have joined the U.S. in creating the International Partnership for a Hydrogen Economy.
An accelerated hydrogen research program is needed now to overcome the substantial technical and economic challenges necessary to achieve long-term energy security. The magnitude of transforming the way we produce and use transportation energy requires a bold program. Business- as-usual approaches haven't worked, and it is time to get serious about our overreliance on foreign oil.
The time has come for action on global warming. The scientific consensus is strengthening that human-induced global warming will not be on the mild side, and may well be catastrophic if we do not quickly start cutting greenhouse gas emissions. Hydrogen cars have little chance of being a cost-effective strategy for reducing those emissions through 2035. They should be put on the back burner while we push fuel efficiency and hybrid vehicles now, followed quickly by hybrids that can be plugged into the electric grid.
We now know that global concentrations of carbon dioxide, the primary greenhouse gas, rose 60% faster in the past three years than in the previous decade. The 11 warmest years on record have all been since 1990. The glacial thinning in the Amundsen Sea area of West Antarctica has doubled since the 1990s, and the entire ice shelf has begun to disintegrate. If we continue on current emissions trends, then by 2040, half the summers will be worse than the extraordinary heat wave that killed 30,000 Europeans in 2003, and we will likely see a "virtually complete melting of the Greenland Ice Sheet, with a resulting sea level rise of about 7 meters (23 feet)," as the 2004 Arctic Climate Impact Assessment concluded.
British Prime Minister Tony Blair said in September 2004 that he believes climate change is the world's "greatest environmental challenge" and committed to "reduce our carbon dioxide emissions by 60% by 2050" to avoid catastrophic climate change. So we must move as fast as possible to zero-carbon sources of energy for our electricity and transportation fuel.
Yet even two well-known California hydrogen advocates, Joan Ogden and Daniel Sperling of the University of California, Davis, acknowledged in a 2004 Issues in Science & Technology article, "Hydrogen is neither the easiest nor the cheapest way to gain large near- and medium-term air pollution, greenhouse gas, or oil reduction benefits." So a focus on hydrogen represents a misdirection of resources away from strategies that can achieve far larger benefits for far less money for decades to come.
When will hydrogen fuel-cell cars be practical? As Bill Reinert, U.S. manager of Toyota's advanced technologies group, said in January 2005, absent multiple technology breakthroughs, we won't see high-volume sales until 2030 or later. Reinert was asked when fuel-cell cars would replace gasoline-powered cars, and he replied, "If I told you 'never,' would you be upset?"
We need a major breakthrough in fuel-cell technology to bring down the cost by more than a factor of 10 while increasing durability and maintaining efficiency. And as a March 2004 report by the American Physical Society concluded, "A new material must be discovered" to make onboard hydrogen storage practical.
Absent breakthroughs, hydrogen cars will remain inferior to the best clean cars available today, gasoline-electric hybrids such as the Toyota Prius, in virtually every respect--cost, range, annual fueling bill, convenience, safety--and in providing cost-effective reductions of greenhouse gas emissions and oil consumption.
Don't get me wrong. I favor keeping the hydrogen option open. I helped oversee the Energy Department's program for clean energy and alternative fuels, including hydrogen, for much of the 1990s, during which time we increased funding for hydrogen 10-fold. But DOE is cutting the budget for efficiency and renewables--technologies that can reduce greenhouse gas emissions cost-effectively today--to fund the hydrogen program, which cannot do so anytime soon. That is a mistake.
Moreover, a 2004 report from the European Union's Joint Research Centre found that hydrogen cars would likely increase greenhouse gas emissions. Hydrogen is not a primary fuel, like oil, for which we can drill. It's bound up tightly in molecules of water or hydrocarbons such as natural gas. A great deal of energy must be used to unbind it. Making that energy causes pollution.
Delivering pollution-free hydrogen to a car is expensive, likely costing the equivalent of $6.00 per gal of gasoline (untaxed) or more for a long time. So we get a bait and switch, with politicians promising renewable hydrogen but then subsidizing polluting hydrogen filling stations. More than 95% of U.S. hydrogen is made from fossil fuels today, and, as a prestigious National Academy of Sciences (NAS) panel concluded in 2004, "It is highly likely that fossil fuels will be the principal sources of hydrogen for several decades."
Furthermore, using renewables to make hydrogen is simply bad policy, even if prices drop sharply. Renewable electricity can achieve far greater pollution reduction by directly displacing coal--or even natural gas--in the power sector. And those savings can be achieved without a massive investment in the hydrogen infrastructure.
So we are several decades from a time when serious investments in hydrogen cars or infrastructure make sense environmentally. While we wait, we must push fuel efficiency and advanced hybrid vehicles to address the urgent problems of global warming and oil imports. We should promote ethanol from sources other than corn as a gasoline blend and begin deploying hybrids that can be plugged into the grid and can run four times as far on a kilowatt-hour of renewable electricity as fuel-cell vehicles.
Hybrids now; hydrogen much, much later.
|DOWN WITH EMISSIONS The bar on the left represents the CO2 savings from renewable electricity used to make hydrogen, assuming the hydrogen is used in a fuel-cell car and displaces the fuel from a hybrid car. The middle bar represents the savings from renewable power displacing electricity from a combined-cycle natural gas power plant. The bar on the right represents the savings from renewable power displacing electricity from a typical coal plant.
Romm wants you to believe that DOE's emphasis on hydrogen research is somehow holding up market-ready hybrid technology and undermining near-term climate-change action. He is wrong. DOE is not diverting resources from other promising technologies and is not rushing to deploy hydrogen vehicles. While deployment of hydrogen vehicles is slated for 2020--by no means a rush--DOE's hybrid components research budget is steadily increasing.
Both global climate change and petroleum dependence are issues that will take decades to fully address, requiring near-term action and long-term revolutionary approaches.
Romm is solely focused on climate change. While warning of catastrophic consequences in the next 40 years, he proposes short-term actions that delay the inevitable need to develop innovative technologies to reach a carbon-neutral future and end petroleum dependence.
Hydrogen offers the opportunity for energy independence and virtually zero greenhouse gas emissions. For long-term economic, energy, and environmental security, we must take action now to develop carbon-neutral domestic energy technologies. We cannot afford, as Romm suggests, to put hydrogen "on the back burner," delaying action for decades. While DOE strongly supports gasoline hybrids for the near-term, we realize that this is not a sustainable approach--these vehicles still use petroleum and still release carbon dioxide from the tailpipe. The NAS report Romm quotes shows that oil use and carbon emissions will never drop below 2005 levels with hybrid vehicles.
Romm correctly states that most hydrogen today is made from fossil fuels (natural gas). What he fails to mention is that fuel-cell vehicles running on natural-gas-based hydrogen would, on a well-to-wheels basis, emit 25% less carbon dioxide than gasoline hybrids. Furthermore, Romm cites reports that miscalculate greenhouse gas emissions by incorrectly characterizing hydrogen production technologies. DOE's strategy does not include hydrogen made from coal-based electricity. Hydrogen will be directly and efficiently produced without intermediate electricity generation, by utilizing instead clean-coal gasification processes. This technology allows carbon dioxide to be captured and sequestered upstream at an ultimate cost of only $10 per ton, so that on a well-to-wheels basis, greenhouse gas emissions are virtually zero.
The U.S. has implemented a comprehensive climate-change technology portfolio totaling $3 billion annually, more than any country in the world. FutureGen, a 10-year, $1 billion government-industry project to demonstrate coal-based, carbon-free electricity and hydrogen generation, will curb greenhouse gas emissions while providing cost-effective energy. DOE helped establish the Carbon Sequestration Leadership Forum, an international initiative focusing on carbon capture and storage technologies to achieve long-term greenhouse gas stabilization, an important endeavor because worldwide fossil energy use for power generation is projected to double by 2030. The Energy Department is also working with international partners to develop a new generation of nuclear reactors and to harness the potential of fusion.
Contentions that budgets for renewable energy have been hurt by DOE's hydrogen investment are incorrect. DOE has a robust renewable R&D portfolio. The department has requested steady increases in funding for wind technologies, which are becoming more cost-effective. Hydrogen is creating more opportunities for wind and solar energy, addressing intermittent availability by providing a storage medium for the electricity. In addition, the DOE hydrogen program is funding direct production of hydrogen from solar energy using photoelectrochemical, biological, and high-temperature thermochemical conversion technologies.
Romm's claims are exaggerated. For example, he says he is "for" hydrogen, implying he increased the hydrogen budget 10-fold. While he was a DOE assistant secretary's deputy, the budget actually grew only 10.5%. Records show Congress deserves the credit for increasing the hydrogen budget in the early to mid-1990s, with appropriations averaging 75% more than DOE's request.
We learned in the 1990s that you cannot mandate alternative-fuel vehicles, as the Energy Policy Act of 1992 did. So DOE has not set sales quotas for hydrogen-fueled vehicles. Our research targets, derived with input from automotive and energy companies, represent what customers demand, so that they will choose this technology.
DOE neither ignores nor discounts the challenges. Advanced technologies for producing, storing, distributing, and utilizing hydrogen are being developed, as is a systems approach to addressing safety related to hydrogen's unique characteristics. Some people have voiced concern that hydrogen could be subject to unusual legal liability concerns such as strict product liability or "abnormally dangerous activity" premises. However, as William Vincent wrote in the Energy Law Journal (2004, 25, 385), "research and experience with hydrogen ... suggest that the opposite may be true," similar to 19th-century legal prognostications over the coming of the horseless carriage. Like any fuel, hydrogen must be handled carefully and in a manner that accounts for its specific properties.
Petroleum dependence and higher levels of atmospheric greenhouse gases did not happen overnight. It will take more than short-term fixes to address the root causes. Saying no to hydrogen is not a plan--it's a roadblock. Romm offers no long-term vision in his article. To seriously address both petroleum dependence and climate change, revolutionary approaches, like hydrogen, are required. Anything short of this is shirking our responsibility to future generations. Revolutionary approaches do entail risk but offer tremendous benefits. DOE, in partnership with major industries, is providing this leadership to make the vision of the hydrogen economy a reality.
Even in DOE's optimistic scenario, hydrogen fuel cells don't enter the vehicle market until 2020 and don't have a significant impact on greenhouse gas emissions for decades. A more realistic 2004 study led by Jae Edmonds of Pacific Northwest National Laboratory concluded that even with multiple technology breakthroughs and a cap on carbon emissions, "hydrogen doesn't penetrate the transportation sector in a major way until after 2035."
We just can't wait that long to take action on global warming.
I agree with Chalk that "hybrids ... will provide the best approach for reducing petroleum consumption over the next 20 years." If only this Administration would use its power to increase fuel-economy standards to take advantage of hybrids--the refusal to do so is the biggest reason we are stuck on a business-as-usual path.
The key question is: What comes after hybrids? Chalk thinks it is hydrogen. I think it is hybrids that can be plugged into the electric grid (e-hybrids) and that can also run on a blend of gasoline and zero-carbon biofuels (ethanol derived from cellulose).
A straightforward improvement to current hybrids can allow them to be plugged into the electric grid and run in an all-electric mode for a limited range between recharging. Since most vehicle use is for short trips, such as commuting, followed by an extended period during which the vehicle is not being driven and could be charged, even a relatively modest all-electric range of 20 miles would allow these vehicles to replace most gasoline consumption and tailpipe emissions.
E-hybrids avoid two of the biggest problems of pure electric vehicles. First, they are not limited in range by the total amount of battery charge. If the initial battery charge runs low, the car can run solely on gasoline and on whatever charging is possible from regenerative braking. Second, electric vehicles take many hours to charge, so that if for some reason owners were unable to allow the car to charge, the pure-electric car could not be driven. Thus, e-hybrids combine the best of hybrids and pure electric vehicles.
The potential greenhouse gas benefits of e-hybrids are even more significant. E-hybrids have an enormous advantage over hydrogen cars in utilizing zero-carbon electricity. That is because of the inherent inefficiency of generating hydrogen from electricity, transporting hydrogen, storing it onboard the vehicle, and then running it through the fuel cell. The total well-to-wheels efficiency with which a hydrogen fuel-cell vehicle might utilize renewable electricity is 20 - 25%. The well-to-wheels efficiency of charging an onboard battery and then discharging it to run an electric motor in an e-hybrid, however, is 75 to 80%--three to four times more efficient than current hydrogen fuel-cell vehicle pathways.
As Alec Brooks, chief engineer of AeroVironment, who led the development of the Impact electric vehicle, has shown, "fuel-cell vehicles that operate on hydrogen made with electrolysis consume four times as much electricity per mile as similarly sized battery electric vehicles." Ulf Bossel, founder of the European Fuel Cell Forum, comes to a similar conclusion in a recent article: "The daily drive to work in a hydrogen fuel-cell car will cost four times more than in an electric or hybrid vehicle."
This relative inefficiency has enormous implications for achieving a sustainable energy future. To replace half of U.S. ground transport fuels (gasoline and diesel) in the year 2050 with hydrogen from wind power, for example, might require 1,400 gigawatts of advanced wind turbines or more. To replace those fuels with electricity in e-hybrids might require under 400 GW of wind. That 1,000-GW difference may represent an insurmountable obstacle for hydrogen as a greenhouse gas mitigation strategy--especially since the U.S. will need several hundred gigawatts of wind and other zero-carbon power sources in 2050 just to sharply reduce greenhouse gas emissions in the electricity sector.
Also, the higher efficiency of e-hybrids means their annual fuel bill will be one-third or one-fourth that of hydrogen fuel-cell vehicles. Not only will they be better for the environment and have a longer range and a much lower infrastructure cost, but they also will be far cheaper to operate.
Ideally, these e-hybrids would also be a flexible-fuel vehicle. Such a car could travel 500 miles on 1 gal of gasoline (and 5 gal of ethanol derived from cellulose) and have under one-tenth the greenhouse gas emissions of current hybrids.
Chalk believes that we need "an accelerated hydrogen research program." I disagree. Recent growth in hydrogen research has come at the expense of other valuable clean-energy programs, including bioenergy, energy efficiency, and advanced vehicle technologies. Congressional earmarks are further diverting hydrogen funding from basic research toward near-term demonstration projects.
We must stop shifting money out of clean-energy programs that can deliver results quickly to spend on hydrogen, which cannot. We should roll back hydrogen and fuel-cell R&D to fiscal 2004 levels (and eliminate most demonstration programs) while sharply increasing funding for biofuels and beginning a major e-hybrid program.