Transport System Fuel. Some passing Comments

In the previous series of posts, I have discussed the question of how we should power our transport systems that currently rely on fossil fuels, and since this will be a brief post, because I have been at a conference for most of this week, I thought it would be useful to have a summary. There are two basic objectives: ensure that there are economic transport options, and reduce the damage we have caused to the environment. The latter one is important in that we must not simply move the problem.

At this stage we can envisage two types of power: heat/combustion and electrical. The combustion source of power is what we have developed from oil, and many of the motors, especially the spark ignition motors, have been designed to optimise the amount of the oil that can be so used. The compression of most spark ignition engines is considerably lower than it could be if the octane rating was higher. These motors will be with us for some time; a car bought now will probably still be on the road in twenty years so what do we do? We shall probably continue with oil, but biofuels do offer an alternative. Some people say biofuels themselves have a net CO2 output in their manufacture. Maybe, but it is not necessary; the main reason would be that the emphasis is put onto producing the appropriate liquids because they are worth more than process heat. Process heating can be provided from a number of other sources. The advantages of biofuels are they power existing vehicles, they can be CO2 neutral, or fairly close to it, we can design the system so it produces aircraft fuel and there is really no alternative for air transport, and there are no recycling problems following usage. The major disadvantages are that the necessary technology has not really been scaled up so a lot of work is required, it will always be more expensive than oil until oil supplies run down so there is a poor economic reason to do this unless missions are taxed, and the use of the land for biofuels will put pressure on food production. The answers are straightforward: do the development work, use the tax system to change the economic bias, and use biomass from the oceans.

There are alternatives, mainly gases, but again, most of them involve carbon. These could be made by reducing CO2, presumably through using photolysis of water (thus a sort of synthetic photosynthesis) or through electricity and to get the scale we really need a very significant source of electricity. Nuclear power, or better still, fusion energy would work, but nuclear power has a relative disappointing reputation, and fusion power is still a dream. Hydrazine would make a truly interesting fuel, although its toxicity would not endear it to many. Hydrogen can work well for buses, etc, that have direct city routes.

Electricity can be delivered by direct lines (the preferred option for trains, trams, etc.), but otherwise it must be by batteries or fuel cells. The two are conceptually very similar. Both depend on a chemical reaction that can be very loosely described as “burning” something but generating electricity instead of heat. In the fuel cell, the material being “burnt” is added from somewhere else, and the oxidising agent, which may be air, must also be added. In the battery, nothing is added, and when what is there is used, it is regenerated by charging.

Something like lithium is almost certainly restricted to batteries because it is highly reactive. Lithium fires are very difficult to put out. The lithium ion battery is the only one that has been developed to a reasonable level, and part of the reason for that is that the original market was for mobile phones and laptops. There are potential shortages of materials for lithium ion batteries, but they would never cut in for those original uses. However, as shown in my previous post, recycling of lithium ion batteries will be very difficult to solve the problem for motor vehicle batteries. One alternative for batteries is sodium, obtainable from salt, and no chance of shortage.

The fuel cell offers some different options. A lot has been made of hydrogen as the fuel of the future, and some buses use it in California. It can be used in a combustion motor, but the efficiencies are much better for fuel cells. The technology is here, and hydrogen-powered fuel cell cars can be purchased, and these can manage 500 km on  single charge, and can totally refuel in about 5 minutes. The problem again is, hydrogen refuelling is harder to find. Methanol would be easier to distribute, but methanol fuel cells as of yet cannot sustain a high power take-off. Ammonia fuel cells are claimed to work almost as well as hydrogen and would be the cheapest to operate. Another possibility I advocated in one of my SF novels is the aluminium/chlorine cell, as aluminium is cheap, although chlorine is a little more dangerous.

My conclusions:

(a)  We need a lot more research because most options are not sufficiently well developed,

(b)  None will out-compete oil for price. For domestic transport, taxes on oil are already there, so the competitors need this tax to not apply

(c)  We need biofuels, if for no other reason that maintaining existing vehicles and air transport

(d)  Such biofuel must come at least partly from the ocean,

(e)  We need an alternative to the lithium ion battery,

(f)  We badly need more research on different fuel cells, especially something like the ammonia cell.

Yes, I gree that is a little superficial, but I have been at a conference, and gave two presentations. I need to come back down a little 🙂

An Imminent Water Crisis?

We have all heard the line “Water water everywhere, nor any drop to drink.” Well, soon we may have to rethink “everywhere”. There was a tolerably scary future hinted at by a recent letter in Nature (de Graaf, et al574: 90). It points out that groundwater is critically important for food production and currently pumping exceeds recharge from rainfall and rivers in many parts of the world. Further, when groundwater levels drop, discharges to streams declines or even stops completely, which reduces river flow, with potentially devastating effects on aquatic life. These authors claim that about 70% of pumped groundwater is used to sustain irrigation and hence food production. There are other problems, such as ground subsidence. If you take away matter from below you, then what you have between you and where you took it must eventually lower, but with land it does not have to do so evenly. Coastal flooding in some US cities is not really exacerbated by climate change to anywhere near the extent it is by the ground lowering due to groundwater removal. 

If the streams to rivers are not recharged, there is a slow desiccation of the nearby land. The billions of tonnes of water locked in soils and bedrock and various aquifers is the biggest single source of fresh water on the planet. Life essentially depends on this resource yet we are unthinkingly depleting it. Most people know that people in dry lands will experience worse conditions due to rising temperatures. What most don’t realise is the inability to properly recharge the aquifers they depend on will lead to even worse problems, not the least through the requirement for more water as temperatures increase.

The paper also provided maps that outline the size of the crisis, but in my opinion also shows a problem inherent in such studies: there was a map that showed the head decline that might lead to a crisis, which really indicates how much groundwater there is. Included is two-thirds of the South Island of New Zealand. Now for parts of Canterbury that may well be the case, but it also includes the West Coast of the South Island. The geology there may well indicate there is not much groundwater, and in fairness I have never heard of anyone drilling wells there, but there is not exactly a water shortage there because the Alps get roughly ten meters of rain a year. The problem for farming in that region is not a shortage of water but rather too much. It is true that farming in Canterbury is probably over-drawing on aquifers, but that is in part because the farmers took to dairying in an area unsuitable for that activity. Prior to the dairy rush, the area was quite prosperous at farming, but without irrigation. Farmers tended to grow grain in the warm dry summers, and would also run sheep. Now wool is not really wanted, so the farmers switched.

Of course, just because I can find a problem in one place does not mean the paper does not raise a valid point. I suspect that when producing a world map like that the authors go to whatever resources they can find and may not check associated issues. So, what are the real problems? In a recent article in Physics World it was stated that within thirty years almost 80% of lands that irrigate through groundwater will reach their limits as wells run dry. It also states that for the other 20% of areas that rely on pumped groundwater, surface flow of streams and rivers has already fallen. This includes cities that depend on pumped water for a water supply. The effects are already being felt in the mid-west of the US.

This raises the question of what can we do about this problem? The most obvious answer is to use less. Most people domestically use far more than necessary, and those who rely on stored rainwater will show how to use less. At the city level, do we really need the number of home pools? On a lesser scale, how many houses really do not waste water? Irrigation needs to be managed in such a way as to lose less by evaporation (i.e. something other than sprinklers.) We need farming methods that are better suited to the local climate, except that also has the problem that we then lose production volumes, and it is far from clear we can afford that.

For coastal cities, desalination offers an answer, but it costs $US1 per 1 – 2 tonne so it is not cheap, and in terms of electrical energy, if we use reverse osmosis, roughly 5 kWh is required, which means we have to significantly increase electrical production. Reverse osmosis works by using pressure to force water through a membrane that will not permit salts to pass, so in principle it could be turned off during peak loads, which might make it useful for a base loading source like nuclear power, but this is not so useful for places distant from the coast. There is another problem with desalination. The seawater should be sterile and the membranes have to be regularly cleaned, which leads to the release of biocides, salts, chelating agents, etc into the sea, which in turn is not particularly good for the local environment.We could pipe water from somewhere else, except we may be running out of “somewhere elses”, and anyway, that place may well be what is feeding the groundwater aquifer. The unfortunate end-result is we may have to give up using so much. We have a problem, Houston!

Protesting on Climate Change

It is interesting these days to see the level of protest; so many people want to protest against doing something. In many cases, that is fair as what they are protesting about should not happen, but then the problem comes, what happens when they get the rhythm, and what sort of protests get results as opposed to the protestors just making a nuisance of themselves? Recently, there were widespread protests here against the inaction of governments on the issue of climate change and that is a fair enough target of protest but how should they go about it? Blocking major roads to prevent traffic from going home after work simply leads to the production of more greenhouse gas. Then there were people here who used superglue to attach themselves to windows. My view on that is they should have been identified so that any bills for damages could be sent, then they be left there. Since they glued their hands, they would need friends to even feed them and a couple of cold fronts were coming.

What I find interesting is that one of the proposed ways of attacking climate change is to plant trees and they even protest about that. They argue the trees grow, then get cut down and the CO2 is returned to the atmosphere so we are no further ahead. In my opinion, that is wrong. First, we buy time. The trees can stand for a reasonable length of time, and further, when we cut them down, we can use the wood to build houses, etc. Leaves fall and return some carbon to the soil. And, of course, when we cut them down, we can replant. But most important, from my point of view, is we can do this now. There is no king hit that will deal with climate change so we shall have to do a very large number of things and unfortunately we don’t actually know how to do many of them beneficially. There is nothing like getting started on what you can do, and that you know what the consequences of doing it are.

Another objection noted in our local paper was that, wait for it, had we started thirty years ago when we knew about the problem this might have worked, but now we need more trees than we can reasonably plant quickly. Well, maybe. It does take time to get the necessary seedlings. The argument seems to be, we can’t solve the entire crisis this way, so why bother? Yes, I know there is no king hit, but if you are going to solve this crisis with a number of different approaches, getting started now is better than not doing anything. As the callers for doing nothing argue, we only have the problem because we did nothing some time ago. Yes, it is true we have wasted a lot of time, but why will wasting more now be beneficial?

Another argument seems to be, the land is too valuable for food production to waste on planting trees. Well, if I look out the window from where I am writing this, I see a range of somewhat tortured hills that stand between 300 to 700 meters above the valley floor, and these hills proceed as hills and steep valleys for a considerable distance. They are largely devoid of big trees, despite the fact that this whole area was initially heavily forested. When the settlers came, the valley was cleared of forest for farmland (farming has now long gone, having been replaced by urban development) then the hillsides were denuded of forest for timber. Now there is light scrub in places, but the big trees are long gone, and this is typical of a lot of land here. Planting trees would stabilise a lot of such steep hillsides, which are often prone to severe erosion, especially with heavy rain, which is expected to become more common over time due to climate change, at least here. For such country where harvesting trees becomes unlikely, by planting a judicious mix of trees such a forest could be self-sustaining so once established and it would store carbon indefinitely.

There are additional benefits of forests. An article in he recent Physics World mentioned that forests decrease the effect of storms, the reason being that the rough land surface offers a frictional restraint on wind speed. The forest has to be reasonably large, and of course the beneficial effects tend to apply to places distant from the coast. The forests also offer a benefit to rainfall through evapotranspiration and it is notable that many areas that are now facing desertification in Africa once had reasonable rainfall and extensive forests. It should be emphasised that forests may also reduce total rainfall by reducing the effect of heavy tropical storms, however in general these do little to provide water in a useful form as the water runs off very quickly. Forests are also beneficial in that they hold up water from heavy rains and allow it to be absorbed by the soil, and hence be available later, and of course, reduce heavy erosion. Also, in areas prone to severe flooding, and we have seen many examples of flooded urban areas on television recently, by holding up the water and thus spreading its movement over more time, the effects of such floods are mitigated. To my mind, anything that achieves more than one benefit is far more worthwhile to pursue.

As for the argument that when the trees mature, they will be harvested and eventually the carbon will return to the atmosphere, I have two responses. First, at least some of it can be stored in buildings, where it will remain for quite some time. Second, you could burn it for fuel or convert it to biofuel, in which case the carbon will return quickly, several decades in the future, but it displaces fossil carbon you would have otherwise converted to CO2, so you are still ahead. Finally, you have bought time to develop new means of solving this problem. And, at the same time, you do generate a future resource, in some cases from land that is otherwise producing nothing except erosion. From my point of view, it probably does not matter whether we act because I shall be dead by the time the really worst of the consequences arrive. However, I would like my grandchildren’s children to have a reasonable chance at life, and that means that we must stop protesting against change because our society cannot continue this way. Change will come; the issue is, what sort of change? Let us control it and make it beneficial.

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.

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.

The Electric Vehicle as a Solution to the Greenhouse Problem

Further to the discussion on climate change, in New Zealand now the argument is that we must reduce our greenhouse emissions by converting our vehicle fleet to electric vehicles. So, what about the world? Let us look at the details. Currently, there are estimated to be 1.2 billion vehicles on the roads, and by 2035 there will be two billion, assuming current trends continue. However, let us forget about such trends, and look at what it would take to switch 1.2 billion electric vehicles to electric. Obviously, at the price of them, that is not going to happen overnight, but how feasible is this in the long run?

For a scoping analysis, we need numbers, and the following is a “back of the envelope” type analysis. This is designed not to give answers, but at least to visualise the size of the problem. To start, we have to assume a battery size per vehicle, so I am going to assume each vehicle will have an 85 kWh battery assembly. A number of vehicles now have more than this, but equally many have less. However, for initial “back of the envelope” scoping, details are ignored. For the current purposes I shall assume an 85 kWh battery assembly and focus n the batteries.

First, we need a graphite anode, which, from web-provided data will require approximately 40 million t of graphite. Since Turkey alone has reserves of about 90 million t, strictly speaking, graphite is not a problem, although from a chemical point of view, what might be called graphite is not necessarily suitable. However, if there are impurities, they can be cleaned up. So far, not a limiting factor.

Next, each battery assembly will use about 6 kg of lithium, and using the best figures from Tesla, at least 17 kg of cobalt. This does not look too serious until we get to multiplying by 1.2 billion, which gets us to 7.2 million tonne of lithium, and 20.4 million t of cobalt. World production of lithium is 43,000 t/a, while that of cobalt is 110,000 t/a, and most of the cobalt goes to other uses already known. So overnight conversion is not possible. The world reserves of lithium are about 16 million t, so there is enough lithium, although since most of the reserves are not actually in production, presumably due to the difficulty in purifying the materials, we can assume a significant price increase would be required. Worse, the known reserves for cobalt are 7,100,000 so it is not possible to power these vehicles with our current “best battery technology”. There are alternatives, such as manganese based cathode additives, but with current technology they only have about 2/3 the power density and they can only last for about half the number of power cycles, so maybe this is not an answer.

Then comes the problem of how to power these vehicles. Let us suppose they use about ¼ of their energy on high-use days and they recharge for the next day. That requires about 24 billion kWhr of electricity generated that day for this purpose. World electricity production is currently a little over 21,000 TWh, Up to a point, that indicates “no problem”, except that over 1/3 of that came from coal, while gas and oil burning added to coal brought the fossil fuels contribution up to 2/3 of world energy production, and coal burning was the fastest growing contribution to energy demand. Also, of course, this is additional electricity we need. Global energy demand rose by 900 TWh in 2018. (Electricity statistics from the International Energy Agency.) So switching to electric vehicles will increase coal burning, which increases the emission of greenhouse gases, counter to the very problem you are trying to solve. Obviously, electricity supply is not a problem for transport, but it clearly overwhelms transport in contributing to the greenhouse gas problem. Germany closing its nuclear power stations is not a useful contribution to the problem.

It is frequently argued that solar power is the way to collect the necessary transport electricity. According to Wikipedia, the most productive solar power plant is in China’s Tengger desert, which produces 1.547 GW from 43 square kilometers. If we assume that it can operate like this for 6 hrs per day, we have 9.3 Gwh/day. The Earth has plenty of area, however, the 110,000 square km required is a significant fraction. Further, most places do not have such a friendly desert close by. Many have proposed that solar panels of the roof of houses could store power through the day and charge the vehicle at night, but to do that we have just doubled the battery requirements, and these are strained already. The solar panels could feed the grid through the day and charge the vehicles through the night when peak power demand has fallen away, so that would solve part of the problem, but now the solar panels have to make sense in terms of generating electricity for general purposes. Note that if we develop fusion power, which would solve a lot of energy requirements, it is most unlikely a fusion power plant could have its energy output varied too much, which would mean they would have run continuously through the night. At this point, charging electric cars would greatly assist the use of fusion power.

To summarise the use of electricity to power road transport using independent vehicles, there would need to be a significant increase in electricity production, but it is still a modest fraction of what we already generate. The reason it is so significant to New Zealand is that much of New Zealand electricity is renewable anyway, thanks to the heavy investment in hydropower. Unfortunately, that does not count because it was all installed prior to 1990. Those who turned off coal plants to switch to gas that had suddenly became available around 1990 did well out of these protocols, while those who had to resort to thermal because the hydro was fully utilised did not. However, in general the real greenhouse problem lies with the much bigger thermal power station emissions, especially the coal-fired stations. The limits to growth of electric vehicles currently lie with battery technology, and for electric vehicles to make more than a modest contribution to the transport problems, we need a fundamentally different form of battery or fuel cell. However, to power them, we need to develop far more productive electricity generation that does emit greenhouse gases.

Finally, I have yet to mention the contribution of biofuels. I shall do that later, but if you want a deeper perspective than in my blogs, my ebook “Biofuels” is 99c this week at Smashwords, in all formats. (https://www.smashwords.com/books/view/454344.)  Three other fictional ebooks are also on discount. (Go to https://www.smashwords.com/profile/view/IanMiller)