Friday, September 29, 2006
Peak Oil: Preparing the Mind.
As I noted in my previous article, we are on a kind of gravy-train, which if it is not accelerating, more passengers are trying to climb onto its back, since all the seats are taken - by the West. However, China and India want what they perceive we have, and who can blame them. In its stringent effort to sell the culture of 'more', advertising has not been slow to portray essentially the same (but with some cultural adjustments) plastic picture of 'wealth' that is the flavour of our daily consumption from the media. The fact, however, is that we need to begin applying the brakes steadily and firmly, rather than crashing them on at some later point of anarchy, when our fossil reserves are depleted to the point that attempting to implement alternative strategies is no longer possible. You do need energy to provide new energy. I am sure that 'the markets' will resist this as long as cash is flowing into pockets, and that will make the jolt rougher when it comes.
In any event, the oil-shift will be an uneven slow-down. It is unlikely to come over days or even a few years, and perhaps will take a few decades. Resources will become more expensive, once it is no longer possible to artificially restrain the costs of oil (as a basic manufacturing feedstock and as a fuel), and then the markets and the shops will have to take-up the slack. As fiscal tensions urge, there is a real danger that the markets may panic, and that could have very serious consequences. I remember the petrol rationing in September 2000. I had been working in Switzerland and returned to the U.K. in the midst of it - I remember thinking that society really does walk along a fine line close to the edge of instability, and it wouldn't take too much to ease it over into anarchy. So, panic is to be avoided, on all levels, and maintaining some essential baseline of supply is mandatory to realising that.
So, as a corollary to my last posting, some clear strategy will be necessary, and we should be able to look to our elected government to provide it. It needs to be done quickly at that. I remain convinced that we can be O.K., but not by continuing as we are. Cutting energy use is a priori, in any sustainable scenario, and probably can be achieved through a combined strategy of efficiency, technology and a degree of frugality. But let's not just give up, and turn ostrich, ignoring the catastrophic consequences of continuing to squander the irreplaceable resource of oil or meekly accepting them as an inevitable fait accomplis.
Wednesday, September 27, 2006
Peak Oil for Sure... but no Need for Panic.
There has been much written on the matter of Peak Oil, including by me in this blog. Peak oil is not that the world is running out of oil per se, but represents a maximum in the production of cheap oil, upon which the industrialised world has been built. The industrial revolution began its life on wood, and garnered momentum in earnest fired by coal. As the decades of the 20th century passed, the availability of cheap oil usurped the underpinning position of coal, and hence as the world production peak looms (friends of mine in the oil industry think it is already here), our accustomed way of life is under threat. Worst case protagonists foresee a "Die-Off", in which the current 6.5 billion world population falls below one billion. That is a simple statistic, and put in real human terms, it is probably unthinkable and certainly unimaginable. True, that huge number of us has only grown upon the cornucopia of cheap oil and gas - the latter being used to make cheap chemical fertilisers upon which we grow 99% of the world's food. Without it, starvation and war seems inevitable.
Die-off could happen, if we simply carried on consuming hydrocarbons (oil and gas) at present rates, until we hit a brick wall, and overnight there was effectively none left. It is more likely that the change will be of a more gradual kind, and things (food included) will become increasingly expensive, thus sifting lifestyles over decades not days. That does not mean that the circumstance will be pleasant, but we should survive. On the news this morning was a sound-bite about the U.K. being Europe's major debtor. If there is an economic recession - which seems possible, if raw-materials and energy become increasingly expensive - people may well lose their jobs, and if they are heavily in debt, they will be in some difficulties. Nonetheless, that is no reason to think that we will experience an immediate social disintegration of "Mad Max" proportions. In any event, the "jolt" of the oil-powered gravy-train we have all been on pulling-up suddenly can be made softer by applying the brakes steadily rather than slamming them on.
Without question, now is the time to rethink our fuel consumption, acceptable levels of transportation, city planning - even if we are best placed to do without cities in the formal sense that we are used to - means for energy efficiency, and energy generation. In my opinion smaller "pods" of up to say 20,000 people, supplied by local farms and provided for in terms of energy using micro-generation: hydro, wind, CHP systems and so on, might be the most practical way to live. A basic grid could be powered using renewables - according to the Oxford University Environmental Change Institute, 20% of our electricity, used nationally, could be produced from "sea-power" (wave and tidal stream), which is the same as is currently made from nuclear power, and so this option should be thoroughly investigated. It seems possible that a nuclear power station might be used on say a county level to run a basic grid, to be tapped into as necessary, but many communities could be exempt from it, running under their own steam, as it were!
Transportation remains a huge problem, consuming around a quarter of all energy used in the U.K. As I have demonstrated, bio-fuels and hydrogen cannot sensibly meet this massive demand. Electric hybrid vehicles could offer an option for providing transport to run on much less fuel (perhaps 80% less, but only if 'battery technology' improves and can be installed sufficiently), but more localised "pod" communities could cut down fuel use by 90% in any case, so there is room to manoeuvre around this issue.
How much time do we have? That is the crux of the matter. As noted, there are oil-experts (people in the oil industry who should know their subject) who think that the peak is with us already. That is, however, not the official stance of the industry. Estimates vary, but 3o years away is as clear to a consensus as I can find. There is of course, the vexed question of exactly how much oil is there in the ground? Conspiracy theorists suggest there is far less than e.g. Saudi claim, and Shell got itself into a lot of trouble a couple of years back, for overstating the volume of their reserves. The mere presence of even an elephant field somewhere (that is oil industry vernacular for a very big field) says nothing about the quality of the oil or the geology through which it must be extracted. I have noted previously that the more fractured is the surrounding rock strata, the less readily will a fluid permeate it. There is evidence too that modern "enhanced" extraction methods have damaged the physical integrity of some fields, and so getting the rest of the oil out may prove more difficult than originally estimated.
I think that the best dipstick for Peak Oil is how production in the existing fields is faring given the unprecedented high price of oil. While the price of West Texas Intermediate oil was above $70 a barrel for much of the first half of 2006, global production was down by over 100,000 barrels a day compared to the previous year. Much of the increase in oil production seen between 2003 and 2005 was due to the OPEC (Middle East, and mainly Saudi), and now there is little or no excess capacity to bring on-stream. There have been many successful new oil extraction projects in the past few years, and more planned for the next 5 years, but they cannot compensate for the decline in the world's many large fields. North Sea production has declined too, from 6.3 million barrels a day in 2001 to 4.5 million barrels daily this year. Mexican oil production is also down by about 100,000 barrels a day in 2006, compared with last year. Worst of all, the mega-giant fields in Ghawar (Saudi) and Burgan (Kuwait) are experiencing severe production difficulties which limits the ability of these countries to increase production.
All the evidence is that Peak Oil is with us (or we have just passed the zenith of production), and so we need to expect and prepare for the inevitable consequences, but not fear for our lives. Since we know all these things, any failure to act will be a fault of greed, since there are many with much to gain from maintaining the status quo for as long as the markets can bear it. Then the brakes will come-on with a slam, and there will be casualties!
Monday, September 25, 2006
Nuclear Fusion Remains a Distant Expensive Dream.
The International Thermonuclear Experimental Reactor (ITER) is due to be constructed in Cadarache, France, rather than in Japan, the other contender location. The project is not cheap since it is expected to run-up a bill of 10 billion Euros ($12.1 billion) over its 30 year lifetime, and even then, if all goes well, there will be no electricity produced from it. It is an experimental reactor (as its name states) and is intended to iron-out the practicalities of nuclear fusion, before any commercial exploitation is sought for the technology. Put another way, ITER is expected to take 10 years to build, run for another 20 years, and if all goes well, a more advanced (still research) machine will then be constructed. After another 30 years, if all still runs smoothly, the first commercial fusion-based electricity "might" come on stream. (60 years in all, and even then it is still "might").
Among the partners in the project are the E.U., France, Japan, South Korea, China, India, Russia and the U.S. In the case of the latter contributor, there has been some internal friction over the funding (1/11 th of the total, or just over £1 billion), because there is in effect competition for the funds with existing U.S. fusion science. This is "big science" in anyone's book, and ITER is the most expensive project after the International Space Station. I have explained in outline the essential principles underlying "nuclear fusion" in an early posting ("Feasible Fusion Power - I doubt it", which I wrote last December). In effect, two atomic nuclei (cores of atoms - in German the word for nucleus is "Kern", as in kernel) both carrying a positive charge must be made to collide with sufficient force to overcome the electrostatic repulsion between the charges, and get them close enough together so they "fuse", releasing a lot of energy in the process. Most of that energy is taken-up by neutrons, which are accelerated ("super-fast"), and then the trick will be to extract the neutrons into a heat exchanger made of some suitable material (no-one knows what, as yet), so and to ultimately generate steam to drive electric-turbines, rather as fission-based nuclear power stations do (and indeed, coal or gas-fired power plants).
The physics of handling such highly energetic neutrons remains another challenge to be met, and although nuclear fusion is hailed as the ultimate "green" power source (just like the Sun!), it isn't since the neutrons will activate the nuclei of the various materials used to construct the reactor itself, which will hence require disposal as radioactive waste. Agreed, these materials will be so intensely radioactive that they will not require disposal over hundreds of thousands of years, but handling such "hot" stuff will need robots not people, and any routine maintenance of the system will also need to be done by robots (another challenge, probably, since developments in robotics may be required?).
Extremely high temperatures are required to achieve fusion, the lowest being around 45 million degrees C, which is enough to bring a deuterium and a tritium nucleus close enough to fuse. To make two deuterium nuclei fuse requires around ten times that at 400 million degrees C. Under such conditions, any matter present exists in the form of a plasma, which is confined in a magnetic bottle arrangement, where the charged bits of atoms and electrons are held in the lines of force of a suitably engineered magnetic field. However, there are crucial difficulties to be overcome in achieving such "confinement", and still, no self-sustaining fusion reaction has so far been demonstrated - i.e. where the plasma can be confined for long enough to reach the "break-even" point, where as much energy is generated by the plasma as is used to produce it.
In view of so many uncertainties, the fact that even according to the best-outcome scenario there will not be any likelihood of a suitable commercial fusion device for 60 years, and the fantastic costs (probably another $100 billion to bring electricity on stream from it - even if it does work, of which there is no guarantee), it is more worthwhile to turn the huge resources involved to more immediate, and better demonstrated, technologies.
Sure, we must break our oil-dependency, but nuclear fusion is not going to do that for us. There must be more emphasis placed upon deriving a realistic plan for renewables (and to what extent they are indeed feasible: see my previous three postings on the subject of "bio-fuels"), and more immediate nuclear technologies (e.g. liquid fluoride thorium reactors, and other uranium-based nuclear programmes). I have commented before that if we were to use the "known" reserves of uranium for nuclear fission, it would probably be used up in about 50 years. However, there are alternative "fast-breeder" programmes possible, which could in principle eke that out for hundreds of years, just so long as we are happy with dealing with the attendant plutonium fuel this inevitably incurs.
Ultimately, small communities ("pods" I have called them), with their energy-needs met by electricity, and which require 90% less transportation fuel, may be our means for sustainable living. At the same time, all means to achieve a more efficient use of whatever energy we do end up with ultimately, should be explored. However, all means for the production of that electricity must be investigated thoroughly too, and there are so many technologies ahead of "fusion" to do that, certainly given the budget set aside for the latter. We are going to run out of fossil-fuel well ahead of any putative nuclear-fusion powered nirvana, and so must act in swift accordance with that inescapable reality.
Friday, September 22, 2006
Biofuels - a Comparison of Practicality.
Most of the world's hydrogen is manufactured from natural gas (methane) by reforming. I have described this before, but it involves reacting methane with steam at high temperatures, when the oxygen from the water extracts the carbon atom from a methane molecule, leaving behind free hydrogen. The resulting carbon monoxide can go on and remove an oxygen atom from another water molecule, thus releasing yet more hydrogen. Most of the hydrogen is used to make ammonia by combining it with nitrogen in the Haber process, for manufacture of fertilizers, and so overall most of the world's food production depends on natural gas, supplies of which in the U.K. and the U.S. are diminishing, and food-production too will depend increasingly on imports of gas.
Therefore, making hydrogen may be worthwhile on a number of counts. Biohydrogen can be made from fermenting sugar, which in an ironic cycle of logic, requires chemical fertilizers (made from natural gas) to grow it. I concluded in the previous two postings that the amount of sugar needed to supply enough hydrogen to replace the 54 million tonnes of oil used to run transport, would vastly exceed the area of arable land in the U.K., even if the implicitly huge hydrogen infrastructure could be implemented.
However, another thought occurred to me. Hydrogen is not the only product of the sugar fermentation process required to generate it, since huge quantities of butyric acid and acetic acid must be produced simultaneously. I now estimate exactly how much of these materials are indeed produced and whether they might be themselves used as a fuel, rather than requiring wholesale disposal, and being wasted.
Burning one mole of butyric acid produces 521.87 kilocalories = 2181.42 kilojoules (kJ) of heat. Similarly, one mole of acetic acid would provide 873.70 kJ of heat.
We have calculated that to make enough H2 to substitute for the 54 million tonnes of oil (equivalent, since it is refined into other fuel fractions) requires the fermentation of 9.94 x 10*8 tonnes of sugar (C6H12O6).
Each tonne ferments as 0.75 tonnes x 58% x 88/180 = 0.213 tonnes of butyric acid; and 0.25 tonnes x 58% x (2 x 60)/180 = 0.097 tonnes of acetic acid. (88 and 60 are the molecular weights of butyric and acetic acids respectively).
Hence the process produces: 0.213 x 9.94 x 10*8 = 2.12 x 10*8 tonnes of butyric acid and
0.097 x 9.94 x 10*8 = 9.64 x 10*7 tonnes of acetic acid. The energy produced by burning these materials may be estimated as follows:
Butyric Acid: (10*6/88) x 2181.42 kJ = 24.79 Gigajoules (GJ), which is equivalent to:
2.12 x 10*8 x (24.79/42) = 125.1 x 10*6 tonnes oil (equivalent).
Acetic Acid: (10*6/60) x 873.70 kJ = 14.56 GJ, which is equivalent to:
9.64 x 10*7 x (14.56/42) = 33.4 million tonnes of oil.
So, out of our 9.94 x 10*8 tonnes of C6H12O6, we get the equivalent of 125.1 million tonnes (butyric acid) + 33.4 million tonnes (acetic acid) + 54 million tonnes (H2) = 212.5 million tonnes of oil, in total.
Hence, we actually need 9.94 x 10*8 x (54/212.5) = 2.53 x 10*8 tonnes C6H12O6 to provide 54 million tonnes oil equivalent of combined fuels. Grown on 2.53 x 10*8/16.53 = 15,281,000 hectares = 153,000 km*2 from sugar cane, or 132,000 km*2 from sugar beet. However, the fermentation vessels would still need to be filled with just over 30 cubic kilometers (km*3) of water, which is 20% of the entire U.K. freshwater capacity, which is already under pressure of supply for drinking, washing and for commerce. Fixing the leaky pipes would stem much of this shortfall, and so perhaps an additional demand could be met if the delivery infrastructure were shored-up!
This figure may be compared with 125,000 km*2 required to grow enough sugar to produce the 76.4 million tonnes of ethanol necessary to stand-in for 54 million tonnes of oil. So, bioethanol scores best in terms of requiring somewhat less land, although growing this amount would still use twice the available arable land area of the U.K. - so no more food production, and we can still only meet half the demand!! However, the amount of water required to run the process is only 2.4 km*3 which is "possible".
As a matter of interest, I note that in an early posting "Biofuels - how practical are they" I quoted that a yield of 2 tonnes of biodiesel/hectare could be obtained, and so 54 x 10*6/2 = 27 x 10*6 ha = 270,000 km*2 of land would be required to meet that fuel requirement (i.e. about twice as bad as for the other potential fuels produced by fermentation).
Hence, I conclude that all these schemes are unworkable on the full scale, without cutting the demand to be met in the first place. To meet a thus reduced scale, bioethanol seems to be the best bet. Hydrogen has all kinds of problems, and using the vile fermentation by-products of butyric acid (essence of sweat) and acetic (raw vinegar) acid would not only be extremely unpleasant (imagine how the world would smell!) but would not get past any health and safety regulations. The latter process is also highly demanding in terms of its water requirements, far more so than ethanol production. It seems that comparatively small quantities of biodiesel might be produced as a precious chemical feedstock, rather than as a fuel, to substitute for some of the (67.4 - 54) = 13.4 million tonnes of petroleum that is imported for use in industry.
Wednesday, September 20, 2006
Bioethanol - The Math.
I shall make a direct comparison between gasoline and ethanol, assuming they are both intended to be burned in internal combustion engines. The efficiency of ethanol in terms of "tank to wheel" might be improved using fuel cells, but this is still firmly in the experimental stage. Currently, the U.K. uses 54 million tonnes of oil (equivalent), which provides:
54 x 10*6 x 42 x 10*9 = 2.268 x 10*18 Joules of energy (J).
Ethanol may be considered as a partially combusted form of fuel (since it contains oxygen, with oil doesn't, being entirely hydrocarbon), and so it delivers less energy when burnt. Specifically, burning one mole of ethanol (46 grams) releases 326.68 kilocalories of energy, and so one tonne of ethanol would provide (10*6/46) x 326.68 x 4.18 = 2.967 x 10*7 kJ = 29.67 Gigajoules (GJ).
This may be compared directly with the figure of 42 GJ quoted for burning one tonne of oil equivalent. Hence we see immediately that ethanol packs around 30% less of a punch than gasoline does, or put another way, a tank full of ethanol will take the car 30% less miles than an equivalent tank filled with gasoline.
We need, therefore, 2.268 x 10*18/29.67 x 10*9 = 76.4 million tonnes of ethanol, which might be produced by fermenting sugar, according to the process:
C6H12O6 --> 2C2H6O (ethanol) + 2CO2.
The process is supposed to be CO2 neutral because the same amount of CO2 produced in the fermentation and ultimate combustion steps will be absorbed by next year's sugar crop (in essence, although in practice the situation is not that good). Assuming that the process is 100% efficient, we can expect to get (2 x 46)/180 - that is the ratio of the molecular weights of ethanol to sugar - or 0.511 tonnes of ethanol per tonne of sugar.
Sugar cane yields a crop of 87 tonnes per hectare (ha), that produces 19% of its weight of sugar, which is 87 x 0.19 = 16.53 tonnes. Hence this should give us 16.53 x 0.511 = 8.449 tonnes of ethanol. Since the density of ethanol is 0.789 kilograms/litre, this would occupy a volume equal to: 8.449 x 1000 /0.789 = 10,706 litres.
The actual production figure is around 6,718 litres/ha, and so the process is 6,718/10,706 = 63% efficient. Indeed this is similar to the efficiency of the fermentation process designed to produce hydrogen from sugar.
6,718 litres of ethanol weighs 0.789 x 6.718 giving a yield = 5.3 tonnes/ha. Hence the sugar crop would require 76.4 x 10*6/5.3 = 14,415,094 ha = 144, 151 square kilometers (km*2). Sugar beet comes in slightly better at 19.1 tonnes/ha and so an equivalent crop would need (16.53/19.1) x 144,151 = 124,755 km*2.
Since the area of arable land in the U.K. is about 65,000 km*2 even of we used all of it and grew no food, we could just about meet half our current fuel requirements from ethanol. Perhaps if we could "seed" more land, we would still need around half the entire area of the U.K. mainland of 244,000 km*2 to produce it!
The message is once again that without severe cuts in transportation use, the situation is hopeless. My figures are rough, and the situation will perhaps be improved by new technologies - but only slightly. Using "bio" fuels to break the hold that imported oil has on us, is really a non-starter, at our current levels of fuel consumption. It is these we need to reduce first and foremost, but that will entail living quite differently ... and probably far more frugally. The option of a Die-Off in human population as energy resources run-out is far more uncomfortable, however.
Monday, September 18, 2006
Hydrogen from Sugar - The Math.
Of the possible energy sources to run transportation as an alternative to oil, hydrogen is often talked about. As I have stressed before, hydrogen is not a fuel, but an energy carrier, and it needs to be produced from a primary fuel such as natural gas, or by electrolysing water using electricity generated from primary fuels, or when that utopia arrives, renewables. Therefore, the prospect of "bio-hydrogen" is very attractive. In order to check the "math", I have worked out what would be required to substitute for the current 54 million tonnes of oil (equivalent) used annually in the U.K. for transportation, nearly a quarter (12 million tonnes) being used by the aviation industry. One method of producing hydrogen is by fermentation of sugars. In the following I shall work in terms of a general formula C6H12O6 (i.e. a sugar such as glucose), bearing in mind that more complex sugars such as sucrose can be broken down to this simpler form. There are two principal fermentation reactions that occur to produce hydrogen:
(a) C6H12O6 + 2H2O --> 2C2H4O2 + 2CO2 + 4H2
(b) C6H12O6 --> C4H8O2 + 2CO2 + 2H2
1 kg of C6H12O6 = 1000/180 = 5.56 moles, and hence 1 kg of C6H12O6 reacting by step (a) yields 5.56 x 4 x 22.5 = 500.4 litres = 0.50 cubic metres (m*3) of hydrogen, H2.
1 kg of C6H12O6 reacting by step (b) yields 5.56 x 2 x 22.5/1000 = 0.25 m*3 of H2. This assumes a yield of 100% for each process.
The actual reaction yields 0.18 m*3 of H2/ kg of C6H12O6. In one study from the University of Glamorgan the ratio of butyric acid/acetic acid is quoted as 1700/780 mg/l, which gives a molar ratio of:
(1700/88)/(780/60) - dividing by the molecular weights - and hence the ratio of reaction (a)/(b) = (780/60 x 2)/(1700/88) = 0.336.
So, 0.18 m*3 of H2 is the product of processes (a) and (b) acting in the proportion: 3 of (a) + 1 of (b) (near enough, it is actually: 2.98 + 1). hence we can assume that 0.75 kg of C6H12O6 reacts by (b) and 0.25 kg of C6H12O6 reacts by (a).
For a 100% yield from the two processes, we expect 0.1875 m*3 of H2 from (b) + 0.125 m*3 from (a) = 0.3125 m*3. Therefore the efficiency of the process is 0.18/0.3125 x 100 = 58%. It is important to note that this efficiency is only attained if the H2 is continually swept from the fermentation vessel, otherwise it falls to 32%, giving a yield of H2 of just 0.1 m*3.
1 tonne oil (equivalent) provides 42 GJ of energy = 42 x 10*9 Joules (J).
Therefore 54 million tonnes would provide 54 x 10*6 x 42 x 10*9 = 2.268 x 10*18 J.
One mole of H2 produces 285.83 kJ/mol when burned (heat of combustion), and so the amount of H2 required is 2.268 x 10*18/285.83 x 1000 J/mol = 7.935 x 10*12 moles of H2 = 1.79 x 10*11 m*3 of H2 (multiplying by the volume of one mole taken as 22.5 litres).
If 1 kg of C6H12O6 produces 0.18 m*3 of H2, we need 1.79 x 10*11/0.18 = 9.94 x 10*11 kg = 9.94 x 10*8 tonnes of C6H12O6.
Sugar cane yields are reported at a maximum of 87 tonnes/hectare (ha) and the crop yields 19% of sucrose, making 16.53 tonnes per hectare.
So we need 9.94 x 10*8/16.53 = 6.01 x 10*7 ha = 6.01 x 10*5 km*2 (square kilometers), or roughly 600,000 km*2. This is to be compared with the entire area of the U.K. mainland of about 244,000 km*2 (of which just 65,000 km*2 is arable). [Sugar beet would be slightly richer as a crop since it produces 19.1 tonnes/ha of sucrose, but we still need just over twice the land area of the U.K.!].
So we need about 250% (two and a half times) the total land area of the U.K. or almost ten-times the amount of arable land there is! Put another way, if we grew no food at all, we could still only supply 10% of our transportation fuel equivalent (or maybe 40% if we managed to "seed" everywhere). On the large scale, this is a non-starter.
Out of interest, let's just consider the total volume of the fermentation vessels. If 0.75 kg of C6H12O6 produces (at 58% yield) (88/180) x 0.75 x 1000 = 213 g butyric acid. Since the butyric acid concentration was quoted at 1700 mg/l (1.7 g/l), the volume of the reactor = 213/1.7 = 125 litres to ferment 1 kg (total, because 0.25 kg reacts by step (a)) of C6H12O6.
Hence, to ferment 9.94 x 10*8 tonnes would require 125 x 1000 kg x 9.94 x 10*8 = 1.243 x 10*14 litres = 1.243 x 10*11 m*3 = 124.3 km*3 (cubic kilometers, since 1 km*3 = 1 x 10*9 m*3). This is to be compared with the entire available freshwater in the U.K. of 148 km*3. So, we could just about match this assuming we had no other need for water (i.e. washing and drinking), and water is already in short supply for even these basic purposes.
Hence on grounds both of providing sufficient land to grow the necessary sugar crop and supplying enough water to fill the fermentation vessels, the prospect is a complete non-starter! I conclude, therefore that biohydrogen is not going to permit us to break our dependency on imported oil from the Middle East.
Friday, September 15, 2006
Air Fleets to Inject SO2 into the Stratosphere.
This cannot be overstated. The Earth is a highly complex machine. By this I do not mean that it is merely complicated, i.e. hard to comprehend because there is a lot to it, but "complex" in the mathematical sense, where the minutiae components function together to produce complexity, akin to chaos theory, where an exact outcome cannot be computed or selected from any number of outcomes for which the nature of each can be clearly predicted. It is this that bedevils predictions about climate change, made from computer models, for example there are large variations in the extent of warming to be expected as CO2 levels rise, ranging between about one and six degrees C over the span of this century.
The cooling effect of an aerosol in the high atmosphere occurs because it reflects the sunlight and hence reduces the amount that reaches the Earth's surface. According to Wigner, the most practical way to get the sulphur dioxide into the atmosphere at the required altitude is to send up fleets of planes - indeed in greater number than the entire world's commercial airline capacity - to take it there. "There" is an interesting point, since "it" lies at around 16 km, which is about the cruising altitude of the Concorde aircraft (scuttled since 9/11), and most aircraft could not fly here, being designed for lower altitudes. We would then, require the wholesale construction of a new purpose-designed fleet of planes to meet the task. Here we go again, another "solution" that seems to demand engineering on the large scale once the idea is addressed a little more closely than is allowed by circumspect reflection. Another method proposed is to mix sulphur compounds into aviation fuel, hence emitting SO2 along with their exhaust gases: but only if they flew at high altitudes, otherwise there would be an impact on the chemistry of the troposphere, with unknown consequences, other than that the sulphuric acid would likely be rained out onto the surface: "acid rain"! Dead lakes and architectural heritage etched away. I have worked as a consultant on the properties of fuel-additives, and I am fairly certain that the presence of sulphur compounds in a fuel would impact significantly and badly on their performance in terms of miles-per-gallon. Stratospheric chemistry is also impacted upon by the presence of water vapour exhausted by planes, which is one argument for curtailing aviation use, and the proposal would require an endorsement that the benefits of injecting SO2 here outweigh those detriments from increased fuel combustion in the higher atmosphere. There is no evidence that it would.
I wonder too, what effect the sudden presence of the unnatural levels of SO2 would have on the essential chemistry of the ozone layer. It could be a molecular equivalent of releasing mink into a land where they have no predators to keep them in check, and decimating indigenous species. So, it is likely that as is the case with nitric acid hydrates in the stratosphere, the sulphuric acid based aerosol would provide ample surfaces on which to catalyse the decomposition of ozone, and so having cut-back on CFC use to repair the ozone layer, we would simply be substituting this form of pollution with another: back to square one, with the ozone-hole stretching elastically overhead, and admitting more UVB and skin-cancers.
Rather like the planes proposed to deliver the putative SO2 "seed" into such elevated climes, I doubt this idea will ever fly! We are again left with the single option of curbing fuel use, and especially aviation fuel, to cut CO2 emissions in an effort to mitigate global warming and the destructive effects of climate change. This is no back-door entrance policy for the aircraft industry.
Wednesday, September 13, 2006
Power from the Ocean Floor?
However, it appears that there is yet another source of energy to be had from the sea. In Finland is a prototype one square metre plastic plate, connected to an hydraulic mechanism, and this is of the kind that the company, AW Energy, is installing in Portugal, at Peniche which is 100 miles up the Atlantic coast from Lisbon. The plates will be anchored to the ocean floor close to the shore at a depth of about 12 metres. They are intended to catch the back and forth motion of underwater swells, to produce kinetic energy which drives a piston-pump and is converted to electricity by onshore generator systems.
In contrast to other wave and wind-based technologies, the ocean-floor approach has the advantage that it is placed underwater, and hence out of sight and out of mind. Apparently, the idea originated from the company's founder, Rauno Koivusaari, who is a professional diver who worked on such projects as undersea cable installations. In the mid-1990's, he was exploring a shipwreck and narrowly avoided being hit by a metal bulkhead door that was flapping back and forth pushed by the deep-water waves. He realised that this kind of effect if harnessed could be used to drive power-production systems, and after a decade or so and a number of tests made by Finland's biggest energy producer, Fortum, along with other companies, and some trials at the European Marine Energy Centre in the Orkneys, now AW Energy is about to use the method to produce real electricity.
Unlike surface waves, underwater waves are more horizontal, and have a more regular and hence predictable pattern. In Peniche, 77% of the waves travel in the same direction, and this is why that particular location has been chosen to anchor the plates which are called "WaveRollers". As Ilkka Hominen (AW Energy) explains: " They will oscillate back and forth on an axle following the movement of the waves. A hydraulic pump will capture the energy and pass it on to a generator hosted in a small cabin onshore - the only visible part of the system." Combine several WaveRoller modules including the cabin which contains the equipment required to connect to the grid, and you have a power station. It sounds neat.
The full environmental impact of the WaveRoller appears to have been well thought through. For example, local fishermen believe that fish will actually be protected by the presence of these devices, and of course there is no hazard to shipping, unlike offshore wind-farms, say. The undersea waves fluctuate far less than surface waves or wind and so a more nearly constant supply might be expected. Routine maintainance and future refurbishment should also be more efficient, as work can be undertaken on one plate at a time, with minimal interruption to the overall output of the "plant". The lubrication of the hydraulics is even to be done using a vegetable-based oil!
Monday, September 11, 2006
9/11... 5 Years on.
I flew from Yerevan airport, over the mighty twin-peaks of Mount Ararat topping 16,000 feet, and over the southern Caucasus to Tbilisi in Georgia: I drew lots with myself as to which had the most cracked and bumpy runway. Yerevan won! Four hours later, the plane landed at London Heathrow Airport. I noticed an edginess to the usually almost perfunctory proceedings. More armed security police; a tighter look in more vigilant eyes. Then I was stopped at customs, which never happens. At least it does at Manchester, but not at Heathrow, or not to me. The customs officer was friendly:
"Can I take a look in your bag?"
"Sure," I answered, having learned from travelling in Russia that the open, loose-armed approach is the best policy. It is almost an instinct now. The man was thorough, but there was nothing untoward.
"Where have you come from?" he asked.
"From Tbilisi, on from Yerevan... Armenia" I answered.
"What were you doing there?" he continued.
"I'm a university professor. I went out to give a lecture." He looked interested, and by then had figured me out as harmless.
"There seems to be more security today?" I said; in the form of a statement veiled in enquiry. But he just nodded and smiled:
"Enjoy the rest of your journey." And that was that. I went home, talked to my wife for a while and the two of us went out for a walk and then for a drink. Then we went home, and having been away for a week or so, I turned on the T.V. to catch up with the news. Instantly, something was badly amiss, and then I saw it... the first plane and the World Trade Centre tower collapsing. And then the second one.
"Karen! The World Trade Centre's been bombed!" We watched the events in disbelief, undoubtedly along with millions of others. I am trying to recall what my immediate thoughts were. There are no words really, but memories are not written in words, but flashes: emotions and pictures. There is an adage, which is true, that no one remembers what you say but how you made them feel.
I felt that I was looking at a world whose certainty had been undermined; it was a different place. It is perhaps in human nature to be smug. To take for granted those things that can be considered as constant. I felt that those constants had been struck from whatever equation I used to calculate my values and my life. I still feel that way, and probably hold on more tightly to things at a more local, more personal level. I have been through my own personal changes since then - unrelated - but the conspiracy of all events since "9/11" has made me analyse who I am and what I believe in. An attempt to sift-out what is worthwhile from the chaff. Family and friends come out top, but I am fearful for the future of the world that has unpicked at its seams since 9/11. Probably the garment was wearing thin in places before that, but I just didn't see it.
Ultimately, that garment is wrapped around an infrastructure based on oil, with major reserves in the Middle East. Tensions and instability in that region have been urged by world politics. However, politics and oil in the Middle East are inextricably connected. Of course they are. How could it be otherwise? Now we see the break-up of the "old boy" oil clubs, dominated by western influence, as Russia, China and south American countries, notably Venezuela, flex their muscles of supply and demand. Will the west become increasingly cut out of the game as China rises in economic prominence, and will this lead to war, since 80% of Chinese oil has to be transported by oil-tanker through straits in Indonesia guarded by U.S. military bases? How will the world respond to stimuli of heat and cold - supply and demand; threat and buddying-up - as each country tries to secure its own share of the future?
Ground Zero, the site where the "twin towers" once stood, and where nearly 3,000 people (office workers and rescue workers) died on that pivotal day five years ago, has another legacy more solid than just its memories, poignant though they must be for the relatives and friends who are left to remember and to contemplate what was... and what might have been. After the bodies were recovered, the detritus of these massive structures needed to be shovelled-up and cleared away. I have read the new term "9/11 widow", which refers to the spouses of workers who have contracted fatal cancers and lung diseases as a result of working in that dust-choked environment. Right from the start, there was much speculation as to what materials exactly they were likely to be exposed to. More than 40,000 people, mostly men, sweated to clear the terrible swathes of smouldering rubble from the aftermath of 9/11. According to a report published last week, 70% of them suffered lung damage as a result of these activities. A New York Lawyer, Marc Bern, said: "There is going to be a new generation of 9/11 widows - more than those created by the original attacks."
The picture in my mind is one of "the law" rubbing its hands all the way to the bank. I am sometimes cynical about what is just and what is legal. Paid for in currency that would not exist without the agency of cheap oil, the decline of which fuels both literally and figuratively this post 9/11 "new age".
Friday, September 08, 2006
Zeolites to Store Hydrogen.
I have noted previously that this term is reminiscent of the reformation of the monasteries, and in practice too, since the methane is broken down and restructured into hydrogen and carbon monoxide, by reaction with steam at high temperatures:
CH4 + H2O --> CO + 3H2.
By an appropriate adjustment of the reaction conditions, an extra molecule of hydrogen can be squeezed out of the system similarly to the "water gas shift reaction", used to enhance the yield of hydrogen for use in the Fischer-Tropsch synthesis of artificial gasoline from coal, which I have discussed previously, hence:
CO + H2O --> CO2 + H2.
Oil, since it is made of hydrocarbons can similarly be converted to hydrogen; hence we have not broken our dependency on gas/oil by using hydrogen per se. Of course, hydrogen can also be produced by the electrolysis of water, but the electricity has to be made by some means, to do it with. Hence we are currently using gas, coal, oil and nuclear for this purpose. I have calculated in some of my earlier postings the huge amount of "renewable" infrastructure that would be needed to make enough hydrogen to substitute for the some 54 million tonnes of oil (equivalent) that we use each year, e.g. by wind-power. Not that I am knocking "renewables" at all since this is where we will need to go eventually, but I think that many who use that word, and ask, "why don't we use more renewables?" don't understand the sheer scale of energy density that we require to be so implemented by its means. There are serious analysts (notably) Ulf Bossel who have concluded that the putative "Hydrogen Economy" is a non-starter. And so it is, in terms of any kind of plastic replication of our status quo using hydrogen; the entire way of life and demand upon energy that we pursue has to change first, before such alternatives are even worth discussing.
So, why is storage of hydrogen such a big deal? There are a number of reasons, is the short answer. It may be feasible to produce hydrogen on a local scale, say to feed community "pods" as I have termed them, to supply essential transportation and to run machinery, especially if there is some local source of electricity e.g. hydroelectric or a wind farm of sufficient extent. However, it is not feasible to generate hydrogen in situ, and effectively burn it at source. The wind doesn't always blow, for instance, and so this secondary energy carrier must be compiled in some way, to be used as necessary. So that implies some system of central "tanks" to put it in. Also, if it is to be used as a "fuel" to run vehicles, it must be put into a fuel-tank of some design, just like gasoline is now. O.K. there are gas-powered cars and trucks, which run on compressed natural gas, and that might be one way of storing hydrogen. However, it takes energy to compress hydrogen, which detracts from the "black" side of the energy balance sheet, and since hydrogen is a very light gas (molecular weight of 2 compared to methane, at 16), the fuel/tank weight ratio (if I can phrase it so) is lower than is practicable. Ideally, that should be at least 6%, and it has been found that some zeolites have a maximum storage capacity of about 4.5% which brings these materials into the range of consideration for this purpose.
Hydrogen can also be liquefied, since a liquid "fuel" packs more of a punch weight for weight than a compressed gas (more molecules per unit volume or mass), but its liquefaction requires even more energy than its compression does. Liquefying hydrogen is difficult in any case, since it is one of (I believe) only three gases known that has a a negative Joule Thompson effect: i.e. the compressed gas warms on expansion, and unless it is first cooled to 193 K it cannot be liquefied by such compression-expansion cycles, as say air can - in order to produce liquid nitrogen as a coolant. On 10 May 1898, James Dewar used it to become the first to statically liquefy hydrogen. Using liquid nitrogen he pre-cooled gaseous hydrogen under 180 atmospheres, then expanded it through a valve in an insulated vessel, also cooled by liquid nitrogen. The process is, as you might imagine, costly in terms of energy. Hydrogen is a highly inflammable gas (think of the R101 Zeppelin going up), and so there are grave worries about the safety of hydrogen as a fuel.
Therefore, storing it in a solid matrix of some kind would be the best means. The Spanish study of zeolite MgY (magnesium exchanged zeolite Y) might therefore look promising. If hydrogen is to be stored in solid materials, a critical balance must be struck, i.e. for an optimum delivery cycle, the adsorption enthalpy should be neither too low (so that suficient storage will occur) nor too high (so that hydrogen can be released on demand. Previous measurements of this quantity for hydrogen adsorbed in zeolites are in the range of about -5 to -10 kJ/mol, all rather shy of the optimum -15 kJ/mol (so the absorption capacity and corresponding weight for weight ratio of hydrogen to the storage material is not ideal). At -17.5 kJ/mol the MgY zeolite seems to be the best yet, and I have no doubt that fine-tuning of this value is possible by varying the presence of other cations (it is not fully-exchanged), or by changing the type of zeolite framework.
Once again, I am left with concerns about scale. Let's just consider the case for the U.K. which uses 54 million tonnes of oil to supply its transportation = 54 x 10*6 x 42 x 10*9 = 2.268 x 10*18 Joules of energy.
Given that the heat of combustion of hydrogen = 285.83 kJ/mole, we would require 7.93 x 10*12 moles of H2 = 1.59 x 10*13 grams = 1.59 x 10*7 tonnes of H2. At an upper absorption capacity of 4.5%, we would need to put this lot into 100/4.5 x 1.59 x 10*7 = 3.53 x 10*8, or around 353 million tonnes of zeolite Y. Since zeolite Y is a synthetic zeolite, it needs therefore to be manufactured. Agreed, we wouldn't need to store an entire year's worth in one go, but say 10% of the total might be a conservative estimate, so we do need to manufacture at least 35 million tonnes of the zeolite. To place this into context, the entire world petrochemical industry only uses around 200,000 tonnes of zeolite Y annually, mainly for cracking oil fractions into gasoline and other fuels. Hence this new hydrogen-based fuel industry would require a considerable scale-up in zeolite production, on a world scale to around 100 times this! 3,500 million tonnes? Even if that quantity of zeolite could be made available, it would still be necessary to keep the material cool, certainly at liquid nitrogen temperature, in order for it to absorb and retain sufficient hydrogen to be any use as a "store" for it. Therefore the energy costs of liquefying sufficient nitrogen coolant should also be factored into the balance sheet.
Whatever course we chose, there is no avoiding the issue of gargantuan energy use. We are merely exposing this central point in different ways, with each new "energy solution" that is discovered, once a simple arithmetic scale-up is applied! Sorry to you guys in Spain; a lovely fundamental result in science, and which may have small scale applications in the future, but we are far from out of the woods yet.
Wednesday, September 06, 2006
"Smoking Gun" Found for Atmospheric CO2.
Now, I will play devil's advocate here. Are the data taken over sufficiently short time intervals, that we may know "exactly" what the changes were immediately preceding each previous "peak" in the geological record? As I recall from previous core samples, they were not, and indeed there was a suggestion that the CO2 maximum came after the temperature maximum, with a lag of about 600 - 900 years. This implies a more complex mechanism than a simple connection between atmospheric CO2 levels and global temperatures. Frighteningly, this may imply that the full "heating effect" of the present atmospheric CO2 has yet to kick-in.
My point is that after each maximum, there has been a plummet in global temperatures, leading into what we know as an "ice-age". Could it be, as some think, that we are on the leading edge of a dramatic climatic event of this kind? I am convinced that human sources of CO2 are the most likely to account for the unequivocal surge in the levels of this greenhouse gas that the ice-core measurements show. However, will the outcome be a very hot Earth or a very cold one?
If the rise is so rapid that the Earth systems are unable to cope with it this is a very bad omen indeed. However, it may be that the systems always break down before an ice-age type switch to a cold period during which a substantial fraction of the "excess" CO2 is adsorbed. Is there sufficient ice-core data available taken say every 10 years for previous maxima to enable us to tell?
In any event, we should be cutting back on our use of fossil fuels, including "oil" to try and ameliorate the potential violence of climatic change in addition to the reason that the stuff is running out!
It is likely that climate change is going to happen whatever we do now, and we should write this into our war-plan for a sustainable society. If an ice-age is due, how will we survive? Is it likely that such an event, say involving a slow-down of the Atlantic Conveyor (of which the gulf-stream is a part, and keeps the U.K. above the temperature of Northern Canada), will be preceded by a decade or decades of unprecedented hot and violent weather? Perhaps there will be no ice-age this time (because of the unprecedented high CO2 levels) and it will just get hotter and hotter - so what do we do then? In all of these scenarios we will need fuel - hence there is no excuse to continue to waste it!
How do we continue to keep warm or cool and feed and water our populations? Localisation is the key feature, although the time may come when it is more expedient for populations to move to either hotter or colder climes in order to survive. It seems a curious notion that the temperature of a region might become a resource along with water, food and fuel, and potentially create another scramble of borders, ownership and wars to decide who is entitled to it!
An ice-age would encourage migration from north-to-south, while unabated heat will drive populations north. Water, however, will become increasingly scarce in addition to a pressure of rising population in either case; if it becomes increasingly locked-up in ice or evaporated by advancing desert.
Monday, September 04, 2006
The Looming Tale of Oil.
An "elephant field" is the term used in the industry to describe a very big reserve. I had thought that no more of these had been discovered for decades, however this morning's programme put me right on this, and it seems that using advanced seismic techniques, where sound-waves are transmitted and reflected through rock-strata, to "x-ray" for oil, such "elephants" are still being located. However, the quality of the oil contained therein and how much can be feasibly extracted therefrom are major points of issue. The final frontier where the elephants live is in ultra-deep water, in sediments at depths of below 10,000 feet. Exploration and extraction from these regimes is on the increase, as it must be since there is nowhere else left to drill.
It was pointed out that the U.S. (and the U.K. and most countries of the industrial world and wanabe industrial economies of Asia) is in a state of complete denial that such an imminent situation exists. It is simply too uncomfortable to contemplate. We have to save oil, but for that to happen, people must believe unequivocally that it is necessary to do so. George Bush has been reported as saying that there is a problem of "oil dependency" but did his scriptwriters use the word "crisis"? And if he read it out, did anybody really believe him?
In short, there is a need to form a "war-plan", but the fact there is an enemy must be laid on with a trowel. There is a need to focus on "better" not necessarily "more". The post-"Peak Oil" age doesn't have to play-out in an apocalyptic scenario, with us all milling in the background as extras in a "Mad Max" movie. We should not think of our predicament as a war over oil (that will merely trigger future conflicts as has fuelled wars in the past. Indeed, all wars are fuelled by oil!), but with "oil dependency" as the enemy, and the culture grown around that which has destroyed important life-elements of human quality, such as "the family". Mankind will not want to turn to a life of "frugality", and with careful planning does not need to. However, a world where every American, European, Chinaman, Indian and South American drives a Hummer is simply not sustainable. I doubt it is even desirable. The west has sent-out the wrong messages to itself and to the developing world: that our ways are all right and theirs are entirely primitive and outmoded. We may learn from each other.
It is energy not money that powers the world fundamentally: the latter is just a system of counters that ultimately only represents the real raw materials, of oil, gas, coal, uranium, gold, platinum, silicon and so on that underpin global world trade. If we had started on our plan for the post-"Peak" world thirty years ago, we would be in better shape to face what is at hand, and still with some slack left. But that is, I suppose, only in the nature of "denial", and acting today is better than waiting until tomorrow. Speak-out, our leaders (Bush and Blair), and prepare us for the inevitable!
Friday, September 01, 2006
$200 a Barrel Forecast for Peak Oil!
The oil industry is more sanguine in its estimates of exactly how much oil there is left on earth in total, and thinks that the peak-oil protagonists are being unnecessarily pessimistic. Russ Roberts of Exxon Mobil Corp. believes that production will continue to rise until 2030, which leaves us sufficient time to develop "alternatives". Daniel Yergin, Chairman of Cambridge Energy Research Associates, is a leading peak-oil critic and in his opinion, production will reach an "undulating plateau" sometime in the future.
Colin Campbell is a major figure in the 'peak-oil is "here" and what are we going to do about it?' school. He says that it is too late to develop alternative sources of power such as solar cells, nuclear reactors and windmills, to fill the gap before energy prices soar. "We have come to the first half of the oil age", he says. Arguably, predictions of oil "running out" are as old as the industry itself, but always new and bigger fields were then discovered "in the nick of time"; however, there have been no such major new discoveries for some decades now, and it may be there are no more to be made. Speculation reigns as to exactly how much oil is contained in particular fields. Shell got itself into some hot-water a couple of years back, over claims that it had deliberately hiked up the estimates of those reserves under its jurisdiction. Given their principal station as the world's main oil-supplier, it is the fields in Saudi that are the focus of particular concern over what resource they do in fact hold. That particular conundrum is compounded by the forced-production methods introduced there, to maintain pace with world demand, which it is thought may have damaged the geology of the region, and even the oil reservoirs themselves.
The ability to extract oil does not depend only on how much oil is contained in a particular reservoir, but on the surrounding geology that permits the oil to flow out from it. Predicting this is rather complicated but in essence, the best flow would be through unobstructed channels in layers of undamaged rock. If the rock becomes "crushed" for whatever reason, the detritus from that will act to impede the flow, and a good "sweet" well may be very hard to get the goods from. Only one well out of every ten "dug" will provide a facile source of oil, and only one in a hundred prove to be a "major field". Hence why exploration for oil is an expensive and demanding enterprise.
It all adds up to the same thing, and matters of exact dates, and so forth are almost an irrelevance. The "peak" in easily extracted (and hence cheap) oil is coming any time now, if it is not already here but camouflaged by enhanced extraction techniques, which permit the exploitation of otherwise low-yield deposits. Oil is about to become much more expensive and the $200 barrel will impact on everything, including food supplies. The situation is most likely worse than having to triple the price of food in the shops (i.e. $70 up to $200), since the markets may "panic" and the instability that would cause could do more economic damage than does the price of oil in its own right.
The world should take heed but not panic. We can get through this, but we have to reassess our demands on oil and energy, and make a stock-review of what is needed. This will not happen though, while money is perceived as the only criterion of import. We need practical solutions based on geology and technology, and perhaps philosophy to create a functionally (never perfect) reasonable society that will be able to thrive even if oil does cost $200 a barrel or even more. The alternative is to permit an anarchic wasteland of human values by default. Poverty of the pocket and of the soul. "For evil to triumph it is only necessary that good men do nothing."