Gee, isn't it easier to try to break or drastically reduce our addiction to fossil fuels??
arthur -----Original Message----- From: Keith Hudson [mailto:[EMAIL PROTECTED] Sent: Wednesday, September 3, 2003 3:55 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: [Futurework] There ain't no hydrogen Ed, As you say, I think we've beaten the previous exchange black and blue and it's time for us to retire to our respective corners and reflect on the good punches that the other might have landed. I will certainly reflect on some of the points you have made -- and, when revived, look forward to our next scrap! However, putting my battered old industrial chemist hat on again -- which I haven't worn for 25 years or so, having diversified in the meantime into architecture, choral music and now evolutionary economics (so help me) -- I'm going to continue with one point on which you are wrong, and give you a short tutorial. The reason I am doing this is not to re-engineer your brain cells in particular (though I hope to do that!) but because there is a great deal of misinformation generally about how a hydrogen economy can come about (particularly by car industry spin doctors). You say: <<<< I agree that we may be facing a potential crisis with regard to energy. However, permit me to be optimistic in thinking that we will resolve it. If it's hydrogen, we won't have to go to war to ensure our supply. It exists in abundance everywhere >>>> There is, in fact, no hydrogen in the world. Or, rather there is no (chemically) free hydrogen -- apart from a miniscule amount which has floated to the top of the stratosphere and then inevitably escapes into outer space because it is so light that even Newton's gravitational force can't hold it down. There is a huge amount of hydrogen on earth but it is all chemically bound to other atoms in molecules. It is bound to carbon in the case of living organic molecules and also in dead organic molecules as in fossil fuels. Also a large amount is bound to oxygen as water. However, to release the hydrogen from these molecular prisons requires energy. In the case of releasing hydrogen from fossil fuel moledcules, it is moderately easy because one uses some fossil fuel molecules to supply the energy (by burning them) to break up other fossil fuel molecules, releasing their bound-up hydrogen. This hydrogen can then be captured in a leak-proof container. (Hydrogen is a very small molecule and can leak through gaps in almost anything.) The hydrogen can then be burned either explosively (as in a normal type of combustion engine in a car) or slowly and smoothly (as in a fuel cell -- from which the useful product is electricity in order to drive an electric engine). (Most of the 'fuel cell' cars that are spoken about will, in fact, be hybrid cars for the next decade or two -- carrying both hydrogen and petrol. They will contain a fuel cell+electric motor and a normal combustion engine. The fuel cell will deliver a largely unvarying amount of electricity which will drive the car at up to a moderate and roughly constant speed along the flat, but when hills are met or sudden bursts of speed are required then the combustion engine will have to cut in. Later, when fossil fuels become very expensive, then cars might be 100% fuel cell but the sort of fuel cell technology that will then be required for practical purposes [that is, for heavy loads or greatly varying speeds] is far in advance of anything that can be achieved, or even contemplated, today.) Back to the hydrogen that is released from fossil fuels -- and its cost. I really don't know the thermodynamic figures off-hand, but a good guess would be that at least one half of fossil fuel molecules would be required to be burned in order to produce the energy required to release the hydrogen from the other half. Thus the cost of running a car with a hydrogen fuel tank would be at least twice the cost of running it on fossil fuel only. Thus the cost of freight and commuting will be at least twice as much as it is now and the cost of hydrogen fuel will *always* be at least twice as much as the market price of fossil fuel, whatever it happens to be. It will never be possible to make hydrogen cheaper (from this source) because of its basic derivation. There is, of course, a great deal more water in the world than fossil fuels. But the energy required to disassociate hydren and oxygen in the water molecule, H2O, is a great deal more than in the case of fossil fuels. Once again I don't know the thermodynamic figures off-hand but it will require at least 5-10 times more energy, and even more so if electricity is used to split the molecule. This illuminates the fallacy of the nuclear power lobby which has recently persuaded Bush that he must build more nuclear power stations even though most of the rest of the developed world are retiring them as quickly as possible. Nuclear power stations are very useful to the electricity grid because their output can be varied according to surges or sudden contractions of demand. (There are, however, other methods of achieving this -- such as local turbines -- which are now becoming just as economic as large fossil-fuel-burning power stations.) However, proponents of nuclear power will point to the electroysis of water and the production of hydrogen as being its main advantage. What these spokesmen never say, however, is that such hydrogen will be at least 20-30 times more expensive than hydrogen produced from fossil fuels. Thus, so far, the hydrogen ecxonomy is not going to be the saviour of the industrial world (and we must remember that we still live, and always will live, in an industrial world of factories, even if most jobs are outside the factories). Hydrogen will become increasingly important but, given present technologies, it will always be considerably more expensive than the naked cost of fossil fuels and, as the latter become increasingly expensive (from the distillation of tar sands and shales -- of which you Canadians have an abundance), there is no escaping from the fact that the whole cost structure of developed economies will change radically -- and adversely -- as the years roll by. There is, however, another method of releasing hydrogen from water and this is by means of using specially engineered bacteria which will use energy either from fossil fuels (or other chemical molecules) or directly from sunlight. At the Ernst Moritz Arndt University in Germany, researchers have found a way to harvest hydrogen from chemical reactions that occur when E. coli consumes sugar. So far, the yield is very lowis and the researchers will have to re-engineer the genes of the bacterium in order to make the process more efficient. And, of course, the sugar has to be grown in the first place, and this requires fertilisers, and this in turn requires fossil fuels to make them. Thus the overall efficiency will not be all that great. The energy gain that will be made eventually is really due to the fact that the process is being basically driven by the sunlight that grows the sugar in the first place. Producing hydrogen from water using sunlight directly as the source of energy is another bacterial route being followed by Craig Venter at the Institute for Genomic Research in Rockville, Maryland (and, undoubtedly by the Chinese who are at the forefront in most genetic research). Firstly, he wants to produce a minimum gene-set bacterium. So far, the bacterium with the smallest number of genes has about 480 but it is believed that the minimum number for an operational bacterium will be about 300. Once this is attained then Venter's intention is then to add the minimum number of requisite genes that will produce hydrogen. He might need another 20-50 for that purpose which will mean a 20-50-stage process of hydrogen production within the cell. However, because intracellular molecular process are perfectly catalysed with something like 99.5% efficiency, then the overall efficiency is likely to be about 70% or so which is about the same as the normal energy capture of growing plants (and about twice as much as any man-made -- extracellular -- chemical processes). (Incidentally, the efficiency of silcon/germanium cell capture of solar energy is about 10-15% and even if it improved it is unlikely ever to reach anywhere near 70%.) Thus it is likely that hydrogen can be "grown" in the future using practical technology which is similar to agriculture -- sunlight to power the system, carbon dioxide from the air, supplies of water and small amounts of trace elements. This 'natural' hydrogen will be cheap and can be produced almost anywhere in the world -- even in the arctic and antarctic regions during the months of sunlight. This will totally transform the basic economic and political structure of the world, because, virtually, only intellectual know-how will be required by way of capital. Terrains which are largely unproductive now, such as deserts and mountainous regions, will be able to be as productive as the richest alluvial soils -- so long as enough water and trace elements can be supplied. Undoubtedly, large corporation will try to monopolise the production of hydrogen by patenting the genetic code of suitable bacteria, but in practice this will be going a step too far. There will be enough scientists who will make sure that the undeveloped world (often countries with lashings of sunlight) are not deprived of the knowledge required. All countries will have the potential to energise whatever technology their intellectual abilities and cultural 'set' allow them to. Furthermore, the basic genetic knowledge that has produced the hydrogen-producing bacterium will also in due course be able to develop much more advanced DNA which will be able to produce tangible consumer goods -- and probably of higher specifications than those of today which uses a basic fossil fuel+ metal-based technology. For example, spider's silk is many times stronger than steel, and the same sort of improvement will be achievable for a great many other materials and products. When will bacterial production of hydrogen begin? Who knows. The problems of adding genes to a minimal bacterium are immense. It is not just a matter of adding specific genes, it is also a matter of the order in which the genes are expressed within the living cell, and this depends on nucleosomes which sheath the DNA which in turn also depends on genes. So it will be a matter of adding a whole complex self-referential system to the basic set-up (which doesn't itself disturb the original basic set-up.). This is probably going to be the most intellectually difficult problem that mankind has ever attempted and its achievement could be anything between ten and a hundreds years down the line. No-one can possibly say at this stage. However, as fossil fuels become increasingly expensive in the coming decades, the prize will be so great that an increasing proportion of research funds will be going into the problem. This endeth the tutorial. Keith Hudson, 6 Upper Camden Place, Bath, England, <www.evolutionary-economics.org> _______________________________________________ Futurework mailing list [EMAIL PROTECTED] http://scribe.uwaterloo.ca/mailman/listinfo/futurework _______________________________________________ Futurework mailing list [EMAIL PROTECTED] http://scribe.uwaterloo.ca/mailman/listinfo/futurework
