The Hydrogen Economy to solve Climate Change?

One of the interesting aspects of climate change is the number of proposals put forward to solve it that do not take into account adverse consequences. There is a strong association of wishful thinking with some of these. On the other side are the gloomy ones, and maybe I fall into that category. What brought that thought to the fore was I have seen further claims for hydrogen as a solution. Why? Well, there are wild claims that wind and solar will solve everything. One problem with these is they tend to deliver their energy in pulses: solar during the day, wind when it is blowing. The net result is that if these can deliver adequate power for all times, there is serious overproduction required at other times. The problem then is how to store this energy. One way is to pump water uphill, but that requires large storage. In a country like New Zealand, where much of the electricity is hydro generated, you would just turn off that generation and use the hydro to manage power demand. However, that assumes there is not a large increase in electricity demand. One proposed solution is to generate hydrogen by electrolysing water. This is a well-understood technology, with no problems, given the power. There are, however, significant economic ones.

This is claimed to solve another problem; a very significant amount of domestic heating is obtained from burning gas. Now, all we have to do is burn hydrogen. We could also use hydrogen in vehicles. My big problem, having worked with hydrogen before, is that it leaks, and is extremely flammable. According to Wikipedia, the flammability range of hydrogen in air is between 4% and 75%; to detonate, the limits are 18.3 – 59% (each by volume), and a leak can support combustion at flow rates as low as 4 micrograms/second. Mixtures can ignite with very low energy input, 1/10 of that needed to ignite gasoline/air, and any static electric spark can ignite it.

The leak problem is made worse by the fact that hydrogen can embrittle metals, and thus create a way for it to escape. It is lighter than air, so it tends to accumulate at the ceilings of buildings, and its very wide explosive range is a broad hazard. The idea that hydrogen could be piped into houses to provide heating is not something I would want to see. The problem is made worse in that you might be sensible and cautious and not take it up, but your neighbour might. The consequences of that can impinge on you. Recently, in Christchurch, a house blew up, and reduced itself to a collection of boards, roofing material, etc., with only the foundations remaining more or less where they started. Several neighbours houses were severely damaged, and made effectively unliveable, at least without major repairs. By some miracle, nobody was killed, although a number had injuries. What apparently happened was a registered gasfitter had done some work on the house’s gas system, there was a natural gas leak, and something ignited it. My guess is, he has some explaining to do, but my point is if this can happen to a registered tradesman, what will happen if there is widespread use of something that leaks with orders of magnitude more ease?

There is a further irony. The objective behind using hydrogen is to help the greenhouse effect by reducing the amount of carbon dioxide we emit. Unfortunately, leaked hydrogen also magnifies the greenhouse effect. At first sight, this does not look right because greenhouse gases work because there is a change of dipole moment in the vibrational mode. This is needed because unless the transition involves a change of electric moment, it cannot absorb a photon. Hydrogen has only one vibrational mode and no electric moment, and no change of electric moment when it is stretched because of its symmetry, i.e.one end of H2 is exactly the same as the other end. There is a minor effect in that the molecule can be polarised for an instant in a collision with something else, but that is fairly harmless.

The problem lies in downstream consequences. One of the important greenhouse gases is methane, emitted by natural gas leaks, farm animals, other farm processes, anaerobic fermentation, etc. Methane is about 35 times more powerful than carbon dioxide as a greenhouse gas, and worse, it absorbs in otherwise transparent parts of the infrared spectrum. (The otherwise does not include other hydrocarbon gases.) However, methane is not as serious as it might be because it is short-lived. UV radiation in the upper atmosphere breaks water, directly or indirectly, into hydroxyl radicals and hydrogen radicals. The hydroxyl radicals rapidly degrade methane, and the hydrogen radicals react with oxygen in the air to make peroxyl radicals that also degrade methane. Molecular hydrogen reacts with both these sort of radicals, and thus indirectly preserves the methane.

There are, of course, other ways of using hydrogen, such as in chemical reactions, including upgrading biofuels, and it can be stored in chemical compounds. Hydrazine (N2H4) is an example of a liquid that could make a very useful fuel. (In the book, and film “The Martian”, the hero has hydrazine from the fuel tank of a rocket, so he catalytically converts it to hydrogen to burn to make water, and blows up his “dome”. It would have been so much easier to burn hydrazine, as it was, after all, from a rocket fuel tank.) Other options include storing hydrogen as hydrides, e.g. borohydrides, or as ammonia, which is cheaper to make than hydrazine, but it is also a gas, unlike hydrazine. The problem is usually how to deliver the hydrogen at a regular and controllable rate.

The use of hydrogen in a chemical manufacturing plant, or when handled with expertise, such as when used by NASA, is no problem. My concern would be for the average person doing repairs themselves to pipes conveying hydrogen, or worse still, plumbing incorrectly. As for having hydrogen as a fuel to be delivered at refuelling stations, I used this concept in my ebook “Puppeteer” to illustrate the potential danger if there are terrorists on the loose.

Biofuels from Algae

In the previous post, I described work that I had done on making biofuels from lignin related materials, but I have also looked at algae, and here hydrothermal processing makes a lot of sense, if for no other reason than algae is always gathered wet. There are two distinct classes: microalgae and macroalga. The reason for distinguishing these has nothing to do with size, but rather with composition. Microalgae have the rather unusual property of being comprised of up to 25% nucleic acid, and the bulk of the rest is lipid or protein, and the mix is adjustable. The reason is microalgae are primarily devoted to reproduction, and if the supply of nitrogen and phosphate is surplus to requirements, they absorb what they can and reproduce, mainly making more nucleic acid and protein. Their energy storage medium is the lipid fraction, so given nutrient-rich conditions, they contain very little free lipids. Lipids are glycerol that is esterified by three fatty acids, in microalgae primarily palmitic (C16) and stearic (C18), with some other interesting acids like the omega-three acids. In principle, microalga would be very nutritious, but the high levels of nucleic acid give them some unfortunate side effects. Maybe genetic engineering could reduce this amount. Macroalgae, on the other hand, are largely carbohydrate in composition. Their structural polysaccharides are of industrial interest, although they also contain a lot of cellulose. The lipid nature of microalgae makes them very interesting when thinking of diesel fuel, where straight-chain hydrocarbons are optimal.

Microalgae have been heavily researched, and are usually grown in various tubes by those carrying out research on making biofuels. Occasionally they have been grown in ponds, which in my opinion is much more preferable, if for no other reason than it is cheaper. The ideal way to grow them seems to be to feed them plenty of nutrients, which leads them to reproduce but produce little in the way of hydrocarbons (but see below) then starve them. They cannot shut down their photosystems, so they continue to take on carbon dioxide and reduce the carbon all the way to lipids. The unimaginative thing to do then is to extract the microalgae and make “biodiesel”, a process that involves extracting the lipids, usually with a solvent such as a volatile hydrocarbon, distilling off the solvent, then reacting that with methanolic potassium hydroxide to make the methyl esters plus glycerol, and if you do this right, an aqueous phase separates out and you can recover your esters and blend them with diesel. The reason I say “unimaginative” is that when you get around to doing this, you find there are problems, and you get ferocious emulsions. These can be avoided by drying the algae, but now the eventual fuel is starting to get expensive, especially since the microalgae are very difficult to harvest in the first place. To move around in the water, they have to have a density that is essentially the same as water, so centrifuging is difficult, and since they are by nature somewhat slimy, they clog filters. There are ways of harvesting them, but that starts to get more expensive. The reason why hydrothermal processing makes so much sense is it is not necessary to dry them; the process works well if they are merely concentrated.

The venture I was involved in helping had the excellent idea of using microalgae that grow in sewage treatment plants, where besides producing the products from the algae, the pollution was also cleaned up, at least it is if the microalgae are not simply sent out into the environment. (We also can recover phosphate, which may be important in the future.). There are problems here, in that because it is so nutrient-rich the fraction of extractable lipids is close to zero. However, if hydrothermal liquefaction is used, the yield of hydrocarbons goes up to the vicinity of over 20%, of which about half are aromatic, and thus suitable for high-octane petrol. Presumably, the lipids were in the form of lipoprotein, or maybe only partially substituted glycerol, which would produce emulsifying agents. Also made are some nitrogen-rich chemicals that are about an order of magnitude more valuable than diesel. The hydrocarbons are C15 and C17 alpha unsaturated hydrocarbons, which could be used directly as a high-cetane diesel (if one hydrogenated the one double bond, you would have a linear saturated hydrocarbon with presumably a cetane rating of 100), and some aromatic hydrocarbons that would give an octane rating well over a hundred. The lipid fraction can be increased by growing them under nutrient-deprived conditions. They cannot reproduce, so they make lipids, and swell, until eventually they die. Once swollen, they are easier to handle as well. And if nothing else, there will be no shortage of sewage in the future.

Macroalgae will process a little like land plants. They are a lot easier to handle and harvest, but there is a problem in obtaining them in bulk: by and large, they only grow in a narrow band around the coast, and only on some rocks, and then only under good marine conditions. If the wave action is too strong, often there are few present. However, they can live in the open ocean. An example is the Sargasso Sea, and it appears that there are about twenty million tonne of them in the Atlantic where the Amazonian nutrients get out to sea. However, in the 1970s the US navy showed they could be grown on rafts in the open ocean with a little nutrient support. It may well also be that free-floating macroalgae can be grown, although of course the algae will move with the currents.

The reason for picking on algae is partly that some are the fastest-growing plants on the planet. They will take more carbon dioxide from the atmosphere more quickly than any other plant, the sunlight absorbed by the plant is converted to chemical energy, not heat, and finally, the use of the oceans is not competing with any other use, and in fact may assist fish growth.

Biofuels as Alternative Fuel Sources

In the previous post I suggested that municipal refuse could be converted to liquid fuels of similar nature to modern hydrocarbon fuels from oil. There are some who think transport can be readily electrified, but three other considerations suggest not. The first is that, as noted by Physics World, a publication by the Institute of Physics, there is a very good chance that a car sold today will still be being used twenty years out. The second is that electric vehicles also have considerable greenhouse emissions. The actual running of the car is free of emissions, but you still have to make the car, which has significant emissions and may exceed that of the standard car; you have to generate the electricity, and the majority of the world’s electricity is generated from fossil fuels, and much from coal; and finally you have to make the batteries, and this is also a serious emitter. There are also parts of the vehicle fleet that will not easily electrify, such as the big road trailers that go into remote Australia, heavy construction equipment, simply because the extra mass to store the batteries would be horrendous, and recharge is not simple in remote places. Shipping will continue to use oil, as will aircraft, and as noted in a previous post, so will much of the vehicle fleet because it is not possible to make satisfactory batteries for replacement vehicles because with current technology there is insufficient cobalt. So what else can replace fossil fuel?

One such possibility is biofuels. The case for biofuels is that in principle their combustion is carbon neutral: their carbon may return to the air, but it came from the air. The energy source is essentially solar, and that is not going to run out soon. The problem then is that biomass is a strange mix of different chemicals. Worse, we eat biomass, and we must not remove our food supply.

The first problem that gives biofuels a bad name is the urge to take the low hanging fruit, especially for tax benefits. Palm oil for biodiesel has made a terrible mess of the Indonesian rain forests, and for what benefit (apart from clipping the tax ticket?) Corn for ethanol similarly makes little sense exceptfor the case where the corn would otherwise go to waste. The problem in part is that corn also utilises so little of the sunlight; most of the plant is simply wasted, and often burned. Seed oils do make sense for specialist uses, such as drying oils in paint, or in cosmetics, or as a feedstock to make other specialist chemicals, but something like “biodiesel” from palm oil makes the overall situation worse, not better. It will never replace the carbon fixed in the rain forest.

Forestry is another interesting case. We are much better off to use the logs for timber in construction: it is worth more, and at the same time it fixes carbon in the buildings. However, if you have ever seen forestry, you will know there is an awful lot of biomass just left to rot: the branches, twigs, stumps, roots, leaves/needles, etc. That is essentially free to use. There are big problems in that it packs extremely badly, so transport costs for any distance are too great.

From a technical point of view, the processes to use woody biomass would come down to the same ones for municipal wastes as noted in the previous post, except that gasification is unlikely to be suitable. A significant plant was put up in the US to gasify biomass and use the gas for a modified Fischer-Tropsch process, but it failed. There were probably several reasons for this, but one is immediately obvious: if we rely on market forces we cannot compete with oil. There are two reasons for that. The first is that the oil is “free” originally, and since liquids can be pumped, it is easily handled, while the second is there is a huge infrastructure to process oil. The cost per unit mass of product becomes lower, usually the ratio of the throughput rates to the power of 0.6. The reason for this is simple. Costs of processing plant are proportional (all other things being equal) to the area of the container, which is proportional to r squared, while the production rate is proportional to volume, which is proportional to rcubed. The huge oil processing plants are extremely efficient, and no much smaller biomass processing unit can have any hope of matching it. The reason for the 0.6 as opposed to 0.66666 is that there are also some extra savings. Control equipment, gauges, etc tend to cost much the same because they are the same, and pumps, etc, tend to be excessively costly when small. The six-tenths rule is, of course, only a rough approximation, but it is a guide.

My approach to this, when I started, was to consider biomass hydrothermal liquefaction. The concept here was that if we merely heated the biomass up with water and simple catalysts under pressure to approaching the critical point, we could end up with liquids. These would have to be refined, but that could be done in a large central plant, while the initial processing could be done in smaller units that could be, with effort, portable. One of the surprises from this was that a certain fraction was already effectively a very high-grade fuel, at least for petrol craft or jet engines without further refining. Exactly what you got depended on catalysts, and a case could also be made to add certain other chemicals to enhance certain products. A lot more work would be needed to get such technology operational, but needing more work is not a reason to discard the concept if saving the world is at stake.

So why did I stop doing this work? Basically, because I felt the desire to change my working environment, and because the funding for this work was drying up. Regarding my working environment, there is a funny story there – well, sort of funny, but it did not feel that way then. The journal Naturedid a quick survey of science in New Zealand. I worked in a Government laboratory, and I had the rather dubious honour of having Head Office describe me in Natureas “an eccentric”. Why? Because I was trying to promote an industry based on a by-product of a synthetic fuels plant constructed at Motunui that would make a key starting material for high-temperature plastics. I suppose some of my antics were unusual, for example there was a program on national television of the dangers of flammable foam plastics, so I went there and pointed out they did not haveto be flammable. I had a piece of foam I had made in the lab that afternoon in the palm of my hand and I fired a gas torch at it so the foam was in my hand, yet yellow-hot on the outside. I held it there for quite some time, until everyone got bored. Anyway, when your employer decides you are eccentric, it felt like time to quit and start up by myself. There were two consequences of this. Before I left, the technical staff made me a brass “eggcup” with a large glass egg in it. One of my prized possessions. The second was I got a letter of apology from Head Office, in which it was explained they did not mean I was eccentric, but rather my ideas were. Not a great improvement, as seen by me. I suppose there was a further example of eccentric behaviour. The laboratory was set up with the purpose of promoting the New Zealand economy by finding new industrial opportunities. I suppose it was somewhat eccentric to actually be following “the Prime Directive”.

Alternative​ Sources for Fuel: Rubbish

As most people have noticed, there is finally some awakening relating to climate change and the need to switch from fossil fuels, not that politicians are exactly accepting such trends, and indeed they seem to have heads firmly buried in the sand. The difficulty is there are no easy solutions, and as I remarked in a previous post, we need multiple solutions.

So what to do? I got into the matter after the first “energy crisis” in the 1970s. I worked for the New Zealand national chemistry laboratory, and I was given the task of looking at biofuels. My first consideration was that because biomass varies so much, oil would always be cheaper than anything else, and the problem was ultimately so big, one needed to start by solving two problems. My concept was that a good place to start was with municipal rubbish: they pay you to take it away, and they pay a lot. Which leads to the question, how can you handle rubbish and get something back from it? The following is restricted to municipal rubbish. Commercial waste is different because it is usually one rather awkward thing that has specific disposal issues. For example, demolition waste that is basically concrete rubble is useless for recovering energy.

The simplest way is to burn it. You can take it as is, burn it, use the heat in part to recover electricity, and dump the resultant ash, which will include metal oxides, and maybe even metals. The drawback is you should take the glass out first because it can make a slag that blocks air inlets and messes with the combustion. If you are going to do that, you might as well take out the cans as well because they can be recycled. The other drawback is the problem of noxious fumes, etc. These can be caught, or the generators can be separated out first. There are a number of such plants operating throughout the world so they work, and could be considered a base case. There have also been quite satisfactory means of separating the components of municipal refuse, and there is plenty of operational experience, so having to separate is not a big issue. Citizens can also separate, although their accuracy and cooperativeness is an issue.

There are three other technologies that have similarities, in that they basically involve pyrolysis. Simple pyrolysis of waste gives an awful mix, although pyrolysis of waste plastics is a potential source of fuel. Polystyrene gives styrene, which if hydrogenated gives ethylbenzene, a very high-octane petrol. Pyrolysis of polyethylene gives a very good diesel, but pvc and polyurethanes give noxious fumes. Pyrolysis always leaves carbon, which can either be burned or buried to fix carbon. (The charcoal generator is a sort of wood pyrolysis system.)

The next step up is the gasifier. In this, the pyrolysis is carried out by extreme heat, usually generated by burning some of it in air, or oxygen. The most spectacular option I ever saw was the “Purox” system that used oxygen to maintain the heat by burning the char that got to the bottom. It took everything and ended up with a slag that could be used as road fill. I went to see the plant, but it was down for maintenance. I was a little suspicious at the time because nobody was working on it, which is not what you expect for maintenance. Its product was supposed to be synthesis gas. Other plants tended to use air to burn waste to provide the heat, but the problem with this is that the produced gas is full of nitrogen, which means it is a low-quality gas.

The route that took my interest was high-pressure liquefaction, using hydrogen to upgrade the product. I saw a small bench-top unit working, and the product looked impressive. It was supposed to be upgraded to a 35 t/d pilot plant, to take up all of a small city’s rubbish, but the company decided not to proceed, largely because suddenly OPEC lost its cohesion and the price of oil dropped like a stone. Which is why biofuels will never stand up in their own right: it is always cheaper to pump oil from the ground than make it, and it is always cheaper to refine it in a large refinery than in a small-scale plant. This may seem to have engineering difficulties, but this process is essentially the same as the Bergius process that helped keep the German synthetic fuels going in WW II. The process works.

So where does that leave us? I still think municipal waste is a good way to start an attack on climate change, except what some places seem to be doing is shipping their wastes to dump somewhere else, like Africa. The point is, it is possible to make hydrocarbon fuels, and the vehicles that are being sold now will need to be fuelled for a number of years. The current feedstock prices for a Municipal Waste processing plant is about MINUS $100/t. Coupled with a tax on oil, that could lead to money being made. The technologies are there on the bench scale, we need more non-fossil fuel, and we badly need to get rid of rubbish. So why don’t we do something? Because our neo-liberal economics says, let the market decide. But the market cannot recognise long-term options. That is our problem with climate change. The market sets prices, but that is ALL it does, and it does not care if civilization eradicates itself in five years time. The market is an economic form of evolution, and evolution leads to massive extinction events, when life forms are unsuitable for changing situations. The dinosaurs were just too big to support themselves when food supplies became too difficult to obtain by a rather abrupt climate change. Our coming climate change won’t be as abrupt nor as devastating, but it will not be pleasant either. And it won’t be avoided by the market because the market, through the fact that fossil fuels are the cheapest, is the CAUSE of what is coming. But that needs its own post.

Climate Change and the Oceans

It appears that people are finally seeing that climate change is real, although the depth of their realization leaves much to be desired. Thus German politicians are going to close down their nuclear reactors and presumably burn more carbon. Not exactly constructive. A number of US politicians simply deny it, as if to say that if you deny it often enough, it will go away. Here in New Zealand we have politicians who say, yes it is real, but what they are doing about it tends to be to encourage electric vehicles and bicycles, with a bit of tree planting. Good intentions, but perhaps the commitment is a little less than necessary, but still better than the heads in sand approach. So, consider the size of the problem: the Intergovernmental Panel on Climate Change has stated that to limit global warming to 1.5 degrees compared with pre-industrial levels could require the removal of 20 billion tonnes of CO2 from the atmosphere each year until 2100. That is a much bigger than average ask. However, planting trees is a start, and the good news is they keep working at it, year after year. So, what to do? In my opinion, there is no one big fix. The concept of beating climate change with a thousand cuts is more appropriate. Part of the problem is to persuade people to do something. They turn around and say, why me? Who pays?

As an example, it has been argued that in the US the application of biochar to soils could improve grain harvests by 4.87 – 6.4 %. The carbon tends to last for maybe hundreds of years, at least to some extent, so the argument goes that it will eventually pay for itself, but initially it is a cost. This works particularly well in acidic heavily weathered soils, where the yields are generally somewhat low because they do not hold nutrients well. This is also not exactly a single bullet solution, since with good uptake, it would sequester and offset about 0.5% of US emissions.

There was an article in a recent edition of Nature that summarised marine geoengineering. Rather pickily, they stated that none of the proposals have been rigorously tested scientifically nor published in peer-reviewed journals. Part of this gripe is fair: they complain that results have been published, but in places like websites that no longer work. That is a separate issue really, and provided the work is properly done, peer-reviewed journals, following editorial contractions to save space, may not be the best. But let us leave that for the moment. The oceans are an attractive place for one reason: they are not doing much else other than being a place for fish to live in. Land tends to be owned, and much is either required for environmental reserves or food production. Certainly, there is a lot of land that is little better than waste, often left over from previous forest harvesting, and there is no reason why this could not be planted. Another useful contribution, but what are the options for the sea?

The first approach noted by Nature is to try to reduce the albedo, by reflecting incoming sunlight. Two ways proposed for doing this would be to put films on the water, or to spray water upwards and let it form clouds. The latter should be reasonably harmless, leaving aside the problem of whether some places might be adversely affected, a problem that applies to any such proposal. The former could have a serious adverse effect on marine life. Squirting water into the air to form clouds would seem to reasonably easily tested, but it also leaves the question, who is going to do it because ultimately this concept involves a cost for which there is no return.

Two more processes noted in the article are the spreading of alkaline rock into the sea to absorb CO2, and the spreading of iron-rich fertiliser to promote the growth of microalgae. The problem for the first is what sort of rock? A billion tonne of burnt lime per year would do, but first it would have to have its CO2 pyrolysed off, so that would emit as much as it saved. We could try basalt, such as peridotite, but if we powdered that it would make more sense to apply it to land where previously we had applied lime because it does much the same job, but also absorbs carbon dioxide. The iron fertiliser case is more interesting. There have been experiments to do this. An example: a ship sailed around, spread the crushed rock, and found that yes, there was a microalgal bloom. However, they also concluded that the amount of carbon that was fixed by sinking to the bottom of the sea was insufficient to justify the exercise. That, however, omits two other thoughts. First, what happened to the algae? If it was eaten by fish (or mammals) that would increase the food supply, and an increase in animal biomass also fixes carbon. The second thought is that if it were harvested, it could well be used to make biofuels, which would reduce the requirement for oil consumption, so that is equally useful. Can it be harvested? That is a question that needs more research. As a general rule, if there is just one thing that needs doing, there is usually a way, if you can find it. The making of fuel is easy. I have done it. There is, of course, the problem of making money from it, and with the current cost of oil that is impossible. Also, scale-up is still a problem to be solved.

The final two proposals were to cultivate macroalgae and to upwell deep water and cool the top. The latter does nothing for the carbon problem, so I shall not think too hard about that, but it is almost essential for the former. In the 1970s the US Navy carried out experiments on growing macroalgae on rafts in deep water, and they only grew when deep water was brought to the surface to act as a fertiliser. These algae can also be used as fuel, or the carbon absorbed somewhere else, and some algae are the fastest growing plants on Earth. It is quite fascinating to watch through a microscope and see continual cell division. This may be easier than some think. Apparently floating Sargassum is filling up some sections of the Atlantic and off the coast of Mexico.

So the question then is, should any of this be done? The macroalgae probably have the lowest probability of undesired side effects, since it is merely farming on water that is otherwise unused. However, to absorb enough carbon dioxide to make a serious difference an awful lot of algae would have to be grown. However, the major oceans have plenty of area.

Global warming and rain.

One day when I was a boy in Hokitika (West Coast, South Island, New Zealand) it was raining when I went to school and it got worse, so I had to walk home through water lying everywhere. The water was up to my ankles everywhere, and deeper in lower lying areas. This did not come from the river, but merely from the rain falling, and in nine hours, from memory there was nine inches of rain (a little under 23 cm). This was regarded as exceptional rain then, a once in a hundred year flood.

Now we have global warming so what do we expect? You hear lots of talk about drought, and yes in some parts of the world there will be drought, but in others there will be more rain. The reason is, if the oceans get warmer more water should go into the air. By itself that may not matter too much if the air gets warmer as well, but problems arise if such warm air meets cooler air. This is the sort of thing that causes rain, but now there is more water in the air.

What happens next depends on exactly how the cause behaved. The obvious thing is the rain falls, but when the humidity collapses into rain drops, its going from the gas phase to liquid releases a lot of energy. If there is enough cold air, it might just heat it, especially if the cold came from mountains forcing the air upwards relatively slowly so that it cools and rains on one side of the mountains. That is what happens around Hokitika. Now the hot air blows a strong warm wind over the land to the east, the so-called föhn wind. If the energy cannot be dissipated that way, then stronger circular winds are generated. The tropical cyclones are examples. There was one recently in Madagascar recently that did extreme damage.

So, how will global warming affect these? The short answer is, there will be a variety of ways. Stronger cyclones, more frequent cyclones (because milder systems that get stronger enter the classification) but the more obvious one is more rain because more water has been evaporated. Which gets me back to Hokitika. They have just had a weather system pass over that lasted about a day and a half of continuous rain, and dumped 800 mm of rain in that period (about 31 ½ inches). That is as much as some places get in a year. A little way inland, in the same period they got 1,082 mm, and that is almost 43 inches.

There has been a variety of flooding around the place. A number of houses were inundated because the storm-water drains could not cope and one woman died. Apparently she was driving; she did not like the speed of the water flowing down the road, so she got out. If when driving you see rapidly flowing water of unknown depth ahead, stop and sit it out, or turn back to higher ground. Do not enter. If you are correct in your fear that a car cannot maintain its grip on the road, you walking would be in a worse position. The force of rapidly flowing water will sweep you off your feet, and if it is deep, you are lighter and therefore have less grip. Your grip depends on your weight.

Probably the most frustrating situation has been for tourists south of the Franz Josef glacier, where they are stranded. To the south, the road is apparently cut off around Haast, and to the north of the Fox Glacier, the Waiho bridge was washed out by a river carrying down quite large boulders. A little earlier there were sightseers walking on the bridge, but fortunately they all got off before the bridge went. To give some idea of the water, here are links to two videos of the bridge going: https://www.youtube.com/watch?v=ldCjVqfkKFk   and  https://www.youtube.com/watch?v=wPf49aaomYI The first one also gives a brief example of the New Zealand accent, and the vernacular. Note the bridge was a Bailey bridge and is in principle not expected to be permanent.

Once something like this happens, the blame game starts. One argument was that the river has a history of flooding and of eroding out the land and changing course, so why build a more permanent bridge? Another was the crossing is situated on a major fault and apparently the land is not good for foundations. I suspect that since it is in a very low population area, money is also a relevant issue. Where I live, there are a number of bridges across the Hutt river, and it runs along a major fault line, but being in a major metropolitan area, bridges are built. However, another more pertinent accusation came from a local who had complained a few days before that someone excavating the riverbed a little upstream had created a channel that would direct the heaviest rocks in a flood in the direction of the first supports to give way. Oops! No doubt more will follow.

When I wrote that (yesterday), the weather system was still to the south of here but working its way north. Yesterday we had wind gusts of up to 120 k/h, and while the system was working its way north, apart from some heavy rain last night, it had run out of steam. Today it is quite warm, sunny, no problem.

So is this a sign of climate change? A single incident is not, however I note that the “one in a hundred year rain event” in my youth has happened again now, and apparently in the 1980s. This time it has dumped almost four times the amount of water, and the Tasman Sea is about two Centigrade degrees above average this summer. You form your own opinion.

Smashwords “Read an Ebook Week”

From Sunday, March 3 to Saturday, March 9, Smashwords is running a sale. The ebooks I have there (https://www.smashwords.com/profile/view/IanMiller) are all discounted. The three fiction books form a series.

 

Puppeteer (https://www.smashwords.com/books/view/69696) is a thriller set  in a future where shortages, government debt, and persistent warfare  are eroding governance. Set in California and Kerguelen, Two pairs of people who are unaware of each others’ existence must combine and succeed in countering a terrorist, or a hundred million people will die and billions of dollars of property will be destroyed.

‘Bot War (https://www.smashwords.com/books/view/677836) In which the problems of Puppeteer have not been addressed. The government is still essentially bankrupt, but Islamic terrorists determined for revenge for what happened in their homeland take control of the latest AI war machines.

Troubles (https://www.smashwords.com/books/view/174203) The world is recovering from a state of anarchy. There is money to be made, and opposition to kill. Law and order is privatized, and those with money have a huge advantage.

Biofuels An Overview (https://www.smashwords.com/books/view/454344) Contrary to what many people say, biofuels could make a serious impact on our carbon dioxide emissions (because while the emissions are the same, the carbon originally came from the atmosphere). There are a number of criticisms, and they are valid for many of the proposals, but that is because the easiest options are the least suitable for various reasons, not the least because there is going to be a major need for food. Find out what the better options are, from someone who has worked on the topic for many years.

Fuel for Legacy Vehicles in a “Carbon-free” Environment

Electric vehicles will not solve our emissions problem: there are over a billion petroleum driven vehicles, and they will not go away any time soon. Additionally, people have a current investment, and while billionaires might throw away their vehicles, most ordinary people will not change unless they can sell what they have, which in turn means someone else is using it. This suggests the combustion motor is not yet finished, and the CO2emissions will continue for a long time yet. That gives us a rather awkward problem, and as noted in the previous posts on global warming, there is no quick fix. One of the more obvious contributions could be biofuels. Yes, you still burn carbon, but the carbon came from the atmosphere. There will also be processing energy, but often that can come from the byproducts of the process. At this point I should add a caveat: I have spent quite a bit of my professional life researching this route so perhaps I have a degree of bias.

The first point is that it will be wrong to take grain and make alcohol for fuel, other than as a way of getting rid of spare or spoiled grain. The world will also have a food shortage, especially if the sea levels start rising, because much of the most productive land is low-lying. If we want to grow biomass, we need an area of land roughly equivalent to the area used for food production, and that land is not there. There are wastelands, but they tend to be non-productive. However, that does not mean we cannot grow biomass for fuel; it merely states there is nowhere nearly enough. Again, there is no single fix.

What you get depends critically on how you do it, and what your biomass is. Of the various processes, I prefer hydrothermal processing, which involves heating the biomass in water up to supercritical temperatures with some additional conditions. In effect, this greatly accelerates the processes that formed oil naturally. Corresponding pyrolysis will break down plastics, and in general high quality fuel is obtainable. The organic fraction of municipal refuse could also be used to make fuel, and in my ebook “Biofuel” I calculated that refuse could produce roughly seven litres per week per person. Not huge, but still a contribution, and it helps solve the landfill problem. However, the best options that I can think of include macroalgae and microalgae. Macroalgae would have to be cultivated, but in the 1970s the US navy carried out an exercise that grew macroalgae on “submerged rafts” in the open Pacific, with nutrients from the sea floor brought up from wind and wave action. Currently there is work being carried out growing microalgae in tanks, etc, in various parts of the world. In principle, microalgae could be grown in the open ocean, if we knew how to harvest it.

I was involved in one project that used microalgae grown in sewage treatment plants. Here there should have been a double benefit – sewage has to be treated so the ponds are already there, and the process cleans up the nitrogen and phosphate that would otherwise be dumped into the sea, thus polluting it. The process could also use sewage sludge, and the phosphate, in principle, was recoverable. A downside was that the system would need more area than the average treatment plant because the residence time is somewhat longer than the current time, which seems designed to remove the worst of the oxygen demand then chuck everything out to sea, or wherever. This process went nowhere; the venture needed to refinance and unfortunately they left it too late, namely shortly after the Lehman collapse.

From the technical point of view, this hydrothermal technology is rather immature. What you get can critically depend on exactly how you do it. You end up with a thick brown fluid, from which you can obtain a number of products. Your petrol fraction is generally light aromatics, with a research octane number (RON) of about 140, and the diesel fraction can have a cetane number approaching 100 (because the main components are straight chain C15 or C17 saturated hydrocarbons. Cetane is the C16 equivalent.) These are superb fuels, however while current motors would run very well on them, they are not optimal.

We can consider ethanol as an example. It has an RON somewhere in the vicinity of 120 – 130. People say ethanol is not much of a fuel because its energy content is significantly lower than hydrocarbons, and that is correct, but energy is not the whole story because efficiency also counts. The average petrol motor is rather inefficient and most of the energy comes out as heat. The work you can get out depends on the change of pressure times volume, so the efficiency can be significantly improved by increasing the compression ratio. However, if the compression is too great, you get pre-ignition. The modern motor is designed to run well with an octane number of about 91, with some a bit higher. That is because they are designed to use the most of the distillate from crude oil. Another advantage of ethanol is you can blend in some water with it, which absorbs heat and dramatically increases the pressure. So ethanol and oxygenates can be used.

So the story with biofuels is very similar to the problems with electric vehicles; the best options badly need more research and development. At present, it looks as if they will not get it in time. Once you have your process, it usually takes at least ten years to get a demonstration plant operating. Not a good thought, is it?

Non-Battery Powered Electric Vehicles

If vehicles always drive on a given route, power can be provided externally. Trams and trains have done this for a long time, and it is also possible to embed an electric power source into roads and power vehicles by induction. My personal view is commercial interests will make this latter option rather untenable. So while external power canreplace quite a bit of fossil fuel consumption, self-contained portable sources are required.

In the previous posts, I have argued that transport cannot be totally filled by battery powered electric vehicles because there is insufficient material available to make the batteries, and it will not be very economically viable to own a recharging site for long distance driving. The obvious alternative is the fuel cell. The battery works by supplying electricity that separates ions and converts them to a form that can recombine the ions later, and hence supply electricity. The alternative is to simply provide the materials that will generate the ions and make the electricity. This is the fuel cell, and effectively you burn something, but instead of making heat, you generate electric current. The simplest such fuel cells include the conversion of hydrogen with air to water. To run this sort of vehicle, you would refill your hydrogen tank in much the same way you refill a CNG powered car with methane. There are various arguments about how safe that is. If you have ever worked with hydrogen, you will know it leaks faster than any other gas, and it explodes with a wide range of air mixtures, but on the other hand it also diffuses away faster. Since the product is water (also a greenhouse gas, but one that is quickly cycled away, thanks to rain, etc) this seems to solve everything. Once again, the range would not be very large because cylinders can only hold so much gas. On the other hand, work has been going on to lock the hydrogen into another form. One such form is ammonia. You could actually run a spark ignition motor on ammonia (but not what you buy at a store, which is 2 – 5% ammonia in water), but it also has considerable potential for a fuel cell. However, someone would still have to develop the fuel cell. The problem here is that fuel cells need a lot more work before they are satisfactory, and while the fuel refilling could be like the current service station, there may be serious compatibility problems and big changes would be required to suppliers’ stations.

Another problem is the fuel still has to be made. Hydrogen can be made by electrolysing water, but you are back to the electricity requirements noted for batteries. The other way we get hydrogen is to steam reform oil (or natural gas) and we are back to the same problem of making CO2. There is, of course, no problem if we have nuclear energy, but otherwise the energy issues of the previous post apply, and we may need even more electricity because with an additional intermediate, we have to allow for inefficiencies.

As it happens, hydrogen will also run spark ignition engines. As a fuel, it has problems, including a rather high air to fuel ratio (a minimum of 34/1, although because it runs well lean, it can be as high as 180/1) and because hydrogen is a gas, it occupies more volume prior to ignition. High-pressure fuel injection can overcome this. However there is also the danger of pre-ignition or backfires if there are hot spots. Another problem might include hydrogen getting by the rings into the crankcase, where ignition, if it were to occur, could be a real problem. My personal view is, if you are going to use hydrogen you are better off using it for a fuel cell, mainly because it is over three times more efficient, and in theory could approach five times more efficient. You should aim to get the most work out of your hydrogen.

A range of other fuel cells are potentially available, most of them “burning” metal in air to make the electricity. This has a big advantage because air is available everywhere so you do not need to compress it. In my novel Red Gold, set on Mars, I suggested an aluminium chlorine fuel cell. The reason for this was: there is no significant free oxygen in the thin Martian atmosphere; the method I suggested for refining metals, etc. would make a lot of aluminium and chlorine anyway; chlorine happens to be a liquid at Martian temperatures so no pressure vessels would be required; aluminium/air would not work because aluminium forms an oxide surface that stops it from oxidising, but no such protection is present with chlorine; aluminium gives up three electrons (lithium only 1) so it is theoretically more energy dense; finally, aluminium ions move very sluggishly in oxygenated solutions, but not so if chlorine is the underpinning negative ion. That, of course, would not be appropriate for Earth as the last thing you want would be chlorine escaping.

This leaves us with a problem. In principle, fuel cells can ease the battery problem, especially for heavy equipment, but a lot of work has to be done to ensure it is potentially a solution. Then you have to decide on what sort of fuel cells, which in turn depends on how you are going to make the fuel. We have to balance convenience for the user with convenience for the supplier. We would like to make the fewest changes possible, but that may not be possible. One advantage of the fuel cell is that the materials limitations noted for batteries probably do not apply to fuel cells, but that may be simply because we have not developed the cells properly yet, so we have yet to find the limitations. The simplest approach is to embark on research and development programs to solve this problem. It was quite remarkable how quickly nuclear bombs were developed once we got started. We could solve the technical problems, given urgency to be accepted by the politicians. But they do not seem to want to solve this now. There is no easy answer here.

Where will the Energy for Electric Vehicles come from?

In the previous post, I looked at the issues involved with replacing all motor vehicles with electric vehicles, and noted that is impossible with what we know now because the necessary materials are just not there. Of course there may be new battery technology developed, but there is another issue: from whence the energy? From international energy statistics, petroleum liquids have the equivalent energy of 53 trillion kWh. Since the electric vehicle is more efficient we can divide that number by about three, so we need almost 18 trillion kWh. (The issue is more complicated by whether we are trying to replace petroleum or solve the transport issue, since some petroleum products are used for heating, but for simplicity I am going to stick with that figure.) If we were going to do that by solar energy, the sunlight gives according to Wikipedia, on average about 3.5 – 7 kWh/m2per day. That needs about five trillion square meters devoted to solar energy to replace petroleum products. The Earth’s area is 510 trillion square meters, so we need about 1% of the surface area devoted solely to this, if the cells are 100% efficient. The highest efficiencies so far (Data from NREL) come from four junctions, gallium arsenide, and a concentrator where 46.6% has been reached. For single junction cells using gallium arsenide, we get 35% efficiency, while silicon cells have reached 27.6%. If silicon, we need 4% of the world’s area.

It is, of course, a bit worse than this because 70% of the world’s surface is ocean, and we can eliminate the polar regions, and we can eliminate the farmland, and we should eliminate the wild-life habitats, and we can probably assume that places like the Sahara or the Himalayas are not available and anyway would be too dusty, too windy, too snowy. Solar energy drops efficiency quite dramatically if the collectors get covered in dust or snow. So, before we get all enthusiastic about solar, note that while it can contribute, equally there are problems. One issue that is seldom mentioned is how we find the materials to make such a huge number of panels. In this context, the world supply of gallium is 180 tonne/a, so basically we should be back to silicon, which is one of the most plentiful elements. (In one of my novels I made a lot of someone finding a source of gallium otherwise overlooked. I feel good about that!). We don’t know how critical element supply would be because currently there is a lot of development work going on on solar conversion and we cannot tell what we will find. The final problem is that latitude also plays a part; in southern England we would be struggling to get the bottom of the range listed above on a sunny day, and of course there are many cloudy days. Accordingly, assuming we do not put the collectors on floats, the required area is starting to get up to 10% of the land area, including highly unsuitable land. We just cannot do it.

That does not mean solar in of no use. One place to put solar panels is on the roof of your house. Superficially, if every motorist did this, the problem is solved, apart from the long-distance driving, at least in the low latitude areas. The difficulty here is that the sun shines in the day, when the commuter uses his car. The energy could be stored, but we have just doubled the battery requirements, and they were already out of hand. You could sell to the power to the grid, and buy power back at night, and there is merit in this as it helps with daylight loads, except that the power companies have to make money, and of course, the greatest normal power requirements are in winter at the beginning and end of the day, when solar is not contributing. So yes, solar power can help, but it is not a single fix. Also, peak power loads are a problem. If the company needs capacity for that, where does it come from? Right now, burning gas or coal. If your electric vehicle is purchased to save the environment from greenhouse gas emission, that is pointless if extra power has to be generated from coal or oil.

My personal view on this is that while renewables are going to be helpful, if we want to stop emitting carbon dioxide when making energy, we have to go partially either nuclear or thermonuclear. My personal preference is for fusion reactors, but we do not know how to make them yet. The main problem with fission reactors is the disposal of waste, and the potential for making materials for bombs. We can get around that if we restrict ourselves to thorium reactors, because the products, while still radioactive, decay much more quickly, and finally you cannot make a thorium bomb. Another benefit of thorium reactors is they cannot get the runaway problems as seen at Chernobyl and Fukushima; they really are very much safer. The problem now is we have not developed thorium fission reactors because everyone uses uranium to make plutonium for bombs.

Even if we manage to get sufficient electricity, the next problem is transmission of this huge increase in electricity. In most countries, the major transmission lines will not take it, and would have to be replaced or supplemented. Not impossible, butat the cost of a lot of carbon dioxide being emitted in making the metals, and transferring them, because massive electric vehicles cannot precede the ability to shift electricity. Again, this is not a problem per se, but it is if we do not get organised quickly. The next problem is to get it to houses. “Slow charging” overnight is probably adequate, even for a tesla. If you can charge it fully in an hour at just over 40 amps, you should need only 3 amps overnight. Not difficult. However, the retail sale of electricity for vehicles travelling is not so easy. It is hard to put figures on this because I don’t know what the demand will be, but charging a vehicle for over an hour means no more than about ten vehicles per day per outlet. It is hard to make money out of that, so you need a lot of outlets. If you have a hundred outlets, you service a thousand cars, say, per day. Still not a lot of profit there and you need a parking lot and some excellent organization. You are also drawing 4,000 amps, so you need a fairly good power supply. Not an enticing proposition for investment.

The point I am trying to make here is that the problem is very large. We have built a monstrous infrastructure around oil, and in the normal circumstances, when we have to change, that industry would go slowly and another would slowly take its place. We don’t have that luxury if we want to save our coastal cities. Yes, everyone can “do their bit”, and that buys time if we all do it, but we also need some bigger help, in organization, research, development and money. It is time for the politicians to stop thinking about the next election, insulting the opposition, and start thinking about their country.