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Media Information Press Release of 18 July 2005 Fuels Come before Fuel Cells by Ulf Bossel The fuel cell effect was discovered and correctly described in 1838 by the Swiss Chemist Christian Friedrich Schönbein. William Robert Grove later matured the discovery to an invention know today as the "fuel cell". After 160 years the innovation was revived and soon became one of the hot topics of scientific research, technical development and capital investment. By electrochemical action fuel cells convert chemical into electrical energy. They are no novel energy sources, but clean and efficient energy converters. Dwindling fossil fuel reserves and global warming provide strong arguments for the establishment of clean and efficient fuel cells as viable energy conversion technology. Unfortunately, the word "fuel cell" has become subject to speculations. Researchers, developers, investors and politicians have inspired each other with optimistic visions. Tax money was hastily committed to research and development, entrepreneurs could easily obtain risk capital, and companies invested their own resources in what they were told to be "their future". The two words "fuel cell" caused another gold rush. However, little attention was paid to fuels for fuel cells. Not all fuel cells are capable of converting commercial fuels into electricity. Of the six better known fuel cell families those with polymer, acidic or caustic electrolytes require clean hydrogen fuel, and another one is made for the conversion of methanol. Only the two high-temperature molten carbonate or solid oxide fuel cells can handle conditioned hydrocarbon fuels directly. The important question, for which fuels should fuel cells be developed, has not been properly considered in the early years of euphoria. After billions of Dollars have been spent on research, development, technology and investments, this question is finally being considered. Unfortunately, nature does not provide hydrogen in its elemental form, but only in chemical combination with other elements. High-grade energy is needed to separate hydrogen from such chemical compounds like water or natural gas. By laws of nature, the energy needed for this process exceeds the energy recovered by re-combining hydrogen with oxygen to water in a fuel cell. Even worse, marketing of hydrogen requires further energy for compression, liquefactions, transport, storage and transfer. After re-conversion of hydrogen to electricity fuel cells only 25% or less of the original electrical energy become available to consumers. In the market place hydrogen always has to compete with its own energy sources, either natural gas or electricity. In a sustainable future after depletion of fossil fuels hydrogen must be derived from water by electrolysis with electricity from renewable sources. However, this electricity can also be distributed to the consumer with highest efficiency through existing power grids. Hydrogen electricity has to compete with line electricity. By laws of physics, hydrogen electricity will always be at least four times more expensive than power from the grid. Furthermore, to meet consumer demands, four renewable power stations have to be built if energy is distributed by hydrogen instead of one for direct power distribution. Three of these stations are needed to cover the internal losses of a hydrogen economy, while only one is producing useful electricity. This makes no sense at all. Energy supply problems cannot be solved by inefficient energy distribution schemes. The cost factor can easily be related to consumer behavior. Most of them will opt for inexpensive grid electricity, not for expensive electricity from fuel cells and hydrogen. Physics speaks against a hydrogen economy. Fundamental laws of nature can never be changed by scientific research, venture capital, majority votes of parliaments or presidential initiatives. A hydrogen economy has no past, no presence and no future. Unfortunately, many elementary facts of a hydrogen economy have been overlooked by its promoters. Where does the energy come from for making hydrogen? Do we have enough water to make for the hydrogen we need? At how many sited do we one or the other, but not both? The following example shows that the establishment of a hydrogen economy needs quantified planning rather than technology development and capital investment. It has been suggested to use liquid hydrogen as aircraft fuel. On average, 520 passenger air planes leave Frankfurt Airport every day. About 50 of them are Boeing 747 ("Jumbo Jets"), each loaded with 130 metric tons (about 160 m3) of kerosene. To carry the same amount of energy each Jumbo has to be loaded with 50 metric tons (because of the much lower density 720 m3) of liquid hydrogen. In total, 2,500 metric tons (36,000 m3) of liquid hydrogen are needed every day to serve the 50 Jumbo Jets. Also, about 22'500 m3 of water and the continuous output of 8 (eight!) 1 GW electric power plants are needed every day for hydrogen production, liquefaction, transport, storage and transfer. If all passenger planes leaving Frankfurt Airport would use hydrogen, about 25 full-size power plants had to be built. Also, the water consumption would be comparable to the water needs of the city of Frankfurt. This simple example reveals that we urgently need a thorough discussion about a sustainable energy future. Visions and wishful thinking cannot provide lasting solutions. Energy problems are not solved by hydrogen visionaries. As the economic success of fuel cells is closely connected to the fuel markets, fuel cells have come to a cross-road. Should one accept commercial carbon-containing fuels now or should one wait for the establishment of a hydrogen economy? Fortunately, the market is reacting in a predictable way. Fuel cells for commercial fuels experience increasing acceptance. It is easier to use high-temperature fuel cells for the conversion of natural gas into electricity than to convert hydrocarbons to clean hydrogen by steam reforming. Not surprisingly, experts now debate the future of fuel cells. Some insist on hydrogen and demand a swift establishment of a hydrogen economy. Public funding should augment private investments in a hydrogen infrastructure. The proponents of this scheme fail to disclose where the energy should to come from and who should bear the cost of for hundreds of new power plants. The answer "energy from renewable sources" is certainly not enough. All promoters of a sustainable energy future draw energy from renewable sources, mostly harvested as electricity. The efficient use of this energy is the key to sustainability. Should renewable electricity be wasted to satisfy a hydrogen dream, or should it be distributed and used with highest efficiency as electricity from the grid? This is the key question, not hydrogen technology. One must assume that economic considerations are behind the hydrogen promotion. Unfortunately, tax money became available before the most fundamental physics of a hydrogen economy have been duly considered. The critical dispute has been muffled by the availability of ample funding. At the present funding levels the hydrogen economy will remain an expensive playground of visionaries. However, the realists are more and more attracted by fuel cells for the direct conversion of carbon-containing fuels into electricity, fuels like natural gas, propane, biogas, coal gas, methanol, ethanol or even vaporized liquid gas station fuels. One should pay more attention to those types of fuel cells in future. This is exactly what happened during the first week of July in Lucerne / Switzerland. During the annual event of the European Fuel Cell Forum experts from all continents gathered to discuss status and prospects of fuel cells with frankness and honesty. Fuel cells of varying designs for application with available fuels were presented in "Fuel Cells for a Sustainable World" (one of two parallel conferences). The final Round Table Discussion made clear that the future role of hydrogen needs to be critically analyzed in depth before further action is taken. Physical arguments speak against a hasty implementation of hydrogen as energy carrier. However, the laws of nature must be respected not only by scientists and engineers, but also by parliaments and political leaders. The future cannot be built on wishful visions. Please send us a copy of any use made of this text. Thank you! >> back to Media Overview |
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