Keith, thank you for the tutorial. I defer to you on the matter of hydrogen and have to admit I didn't know what I was talking about. You don't know how hard that is for me to do.
Ed Weick ----- Original Message ----- From: "Keith Hudson" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Wednesday, September 03, 2003 3:55 AM Subject: 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
