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Spencer Abraham's Hydrogen Dream The media was all aglow recently with Spencer Abraham's announcement that the U.S. now has a roadmap for making the transition to a hydrogen economy. Secretary of Energy Abraham announced the plan at the Global Forum on Personal Transportation held in Dearborn, Mich. In his presentation, he touted the line that hydrogen produced from renewable resources can provide unlimited energy with no impact on the environment. Secretary Abraham noted that the transition to hydrogen would be a long-term process, which will require the participation of both industry and government. As a first step, in January 2002 Secretary Abraham, along with officials from the automotive industry and Congress, unveiled a FreedomCAR partnership to develop hydrogen fuel cell vehicles. The National Hydrogen Energy Roadmap is available on the internet in pdf form. This roadmap glows with positive energy. In all areas of production, delivery, storage, conversion and applications, the document beams about what we can achieve if we put our minds to it, but inevitably winds up by saying that we have a long way to go in order to make it a reality. The document does mention the various challenges to each area of fuel cell development, but makes little of the obstacles and instead comes off sounding like a pep talk. Buried in the text, they admit "The transition to a hydrogen economy... could take several decades to achieve." The document speaks of wind, solar and geothermal production, biomass, nuclear-thermo-chemical water splitting, photoelectrochemical electrolysis, and bioengineering. But they admit that all of these processes will require a great deal more research. The intention is to bootstrap the move by first developing small "reformers" that will run on natural gas, propane, methanol or diesel. But the authors admit that even this technology requires further refinement for improved reliability, longer catalyst life, and integration with storage systems and fuel cells. The document also includes a short list of people who are in charge of various areas of development and transition. The list includes: Frank Balog of Ford Motor Company, Gene Nemanich of ChevronTexaco Technology Ventures, Mike Davis of Avista Labs Energy, Art Katsaros of Air Products and Chemicals Incorporated, Alan Niedzwiecki of Quantum Technologies, Joan Ogden of Princeton University Systems, and Jeff Serfass of The National Hydrogen Association. This team will ensure that the new technology remains firmly in the hands of the top corporations. The document is at least 80 percent public relations. While admitting that in all areas there are serious problems to be overcome before we will be able to make a transition to hydrogen fuel cells, nowhere does this document take a serious look at the obstacles. Instead, this paper paints a pretty picture of our hydrogen future and leaves the details to future research and investment. So let us look at a few of the difficulties of developing a hydrogen fuel cell economy. First off, because hydrogen is the simplest element, it will leak from any container, no mater how strong and no matter how well insulated. For this reason, hydrogen in storage tanks will always evaporate, at a rate of at least 1.7 percent per day. Hydrogen is very reactive. When hydrogen gas comes into contact with metal surfaces it decomposes into hydrogen atoms, which are so very small that they can penetrate metal. This causes structural changes that make the metal brittle. Perhaps the largest problem for hydrogen fuel cell transportation is the size of the fuel tanks. In gaseous form, a volume of 238,000 litres of hydrogen gas is necessary to replace the energy capacity of 20 gallons of gasoline. So far, demonstrations of hydrogen-powered cars have depended upon compressed hydrogen. Because of its low density, compressed hydrogen will not give a car as useful a range as gasoline. Moreover, a compressed hydrogen fuel tank would be at risk of developing pressure leaks either through accidents or through normal wear, and such leaks could result in explosions. If the hydrogen is liquefied, this will give it a density of 0.07 grams per cubic centimeter. At this density, it will require four times the volume of gasoline for a given amount of energy. Thus, a 15-gallon gas tank would equate to a 60-gallon tank of liquefied hydrogen. Beyond this, there are the difficulties of storing liquid hydrogen. Liquid hydrogen is cold enough to freeze air. In test vehicles, accidents have occurred from pressure build-ups resulting from plugged valves. Beyond this, there are the energy costs of liquefying the hydrogen and refrigerating it so that it remains in a liquid state. No studies have been done on the energy costs here, but they are sure to further decrease the Energy Return on Energy Invested (EROEI) of hydrogen fuel. A third option is the use of powdered metals to store the hydrogen in the form of metal hydrides. In this case, the storage volume would be little more than the volume of the metals themselves. Moreover, stored in this form, hydrogen would be far less reactive. However, as you can imagine, the weight of the metals will make the storage tank very heavy. Now we come to the production of hydrogen. Hydrogen does not freely occur in nature in useful quantities, therefore hydrogen must be split from molecules, either molecules of methane derived from fossil fuels or from water. Currently, most hydrogen is produced by the treatment of methane with steam, following the formula: CH4 (g) + H2O + e > 3H2(g) + CO(g). The CO(g) in this equation is carbon monoxide gas, which is a byproduct of the reaction. Not entered into this formula is the energy required to produce the steam, which usually comes from the burning of fossil fuels. For this reason, we do not escape the production of carbon dioxide and other greenhouse gases. We simply transfer the generation of this pollution to the hydrogen production plants. This procedure of hydrogen production also results in a severe energy loss. First we have the production of the feedstock methanol from natural gas or coal at a 32 percent to 44 percent net energy loss. Then the steam treatment process to procure the hydrogen will result in a further 35 percent energy loss. It has often been pointed out that we have an inexhaustible supply of water from which to derive hydrogen. However, this reaction, 2H2O + e = 2H2(g) + O2(g), requires a substantial energy investment per unit of water (286kJ per mole). This energy investment is required by elementary principles of chemistry and can never be reduced. Several processes are being explored to derive hydrogen from water, most notably electrolysis of water and thermal decomposition of water. But the basic chemistry mentioned above requires major energy investments from all of these processes, rendering them unprofitable in terms of EROEI. Much thought has been given to harnessing sunlight through photovoltaic cells and using the resulting energy to split water in order to derive hydrogen. The energy required to produce 1 billion kWh (kilowatt hours) of hydrogen is 1.3 billion kWh of electricity. Even with recent advances in photovoltaic technology, the solar cell arrays would be enormous, and would have to be placed in areas with adequate sunlight. Likewise, the amount of water required to generate this hydrogen would be equivalent to 5 percent of the flow of the Mississippi River. As an example of a solar-to-hydrogen set up, were Europe to consider such a transition, their best hope would lie in erecting massive solar collectors in the Saharan desert of nearby Africa. Using present technology, only 5 percent of the energy collected at the Sahara solar plants would be delivered to Europe. Such a solar plant would probably cost 50 times as much as a coal fired plant, and would deliver an equal amount of energy. The basic problem of hydrogen fuel cells is that the second law of thermodynamics dictates that we will always have to expend more energy deriving the hydrogen than we will receive from the usage of that hydrogen. The common misconception is that hydrogen fuel cells are an alternative energy source when they are not. In reality, hydrogen fuel cells are a storage battery for energy derived from other sources. In a fuel cell, hydrogen and oxygen are fed to the anode and cathode, respectively, of each cell. Electrons stripped from the hydrogen produce direct current electricity which can be used in a DC electric motor or converted to alternating current. Because of the second law of thermodynamics, hydrogen fuel cells will always have a bad EROEI. If fossil fuels are used to generate the hydrogen, either through the Methane-Steam method or through Electrolysis of Water, there will be no advantage over using the fossil fuels directly. The use of hydrogen as an intermediate form of energy storage is justified only when there is some reason for not using the primary source directly. For this reason, a hydrogen-based economy must depend on large-scale development of nuclear power or solar electricity. Therefore, the development of a hydrogen economy will require major investments in fuel cell technology research and nuclear or solar power plant construction. On top of this, there is the cost of converting all of our existing technology and machinery to hydrogen fuel cells. And all of this will have to be accomplished under the economic and energy conditions of post-peak fossil fuel production. Based on all of this, I submit that Secretary of Energy Spencer Abraham does indeed have ulterior motives for his Hydrogen Energy Roadmap. First, I suggest that this distant goal will help to pacify the public once they begin to suffer from the effects of fossil fuel withdrawal. Secondly, this project will allow the elite to transfer more money from the general public to the pockets of the rich. Third, in the words of Karl Davies, this proposal will deflect a stock market collapse once news of declining oil production becomes generally recognized. Tied to this, it will brace stock prices of the auto
corporations and oil majors to help them survive well into the era of oil
depletion. And finally, the idea that we are working on a transition from
fossil fuels to a hydrogen-based economy will help to destabilize OPEC,
hopefully making it easier to deal with that organization and the Arab oil
states. Reactions from Jan Lundberg's colleagues: The From the Wilderness
author didn't talk about reducing the demand for energy 50%, 90% maybe Michael Winkler, Arcata, Calif. energy activist More information of fuel cell technology Back to alternative energy index |
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