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.

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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.

Climate Change: the Potential for Electric Vehicles

In my last post, I discussed the need for action over climate change. Suppose we decide to be more responsible, what can we do? There are several issues, but the main ones include is a solution fit for purpose, which includes will the general population see it as such and does it achieve a useful goal, and is it actually possible? To illustrate what I mean, consider the “easy option”: scrap motor cars and replace with electric vehicles. At first sight, that is easy and you will probably think there is no technological advance needed. Well, think again on both of those. Let’s put numbers on the problem: according to Wikipedia, the number of motor vehicles in the world is 1.015 billion.

Now, to consider the issue, “fit for purpose”, in New Zealand, anyway, and I suspect North America will be worse, people drive fairly long distances at least some of the time. One solution to that problem is to make people stop doing that. This is from the “sacrifices have to be made” school. As it happens, energy consumption probably will have to be reduced, but that does not mean that we need some politicians to say which form of energy consumption is forbidden to you. If people must use less, they should have a choice in what form they give it up.

There are two “niches” of electric vehicle, and as examples I shall pick on the Tesla and the Nissan Leaf. The Tesla currently claims a 400 km range (and intends to provide a 500 km range) per charge, while what you get from the Leaf is highly dependent on driving conditions, but it reaches a little over 100 km with average city driving. Basically, the Leaf would be great for someone wishing to commute daily, but not use it for distance driving. As an aside, the dependency on conditions will affect all such cars; we know about this aspect of the Leaf because there is more information available as more Leafs have been sold. The difference in range is simply because the Leaf’s battery is much smaller (198 cells compared with Tesla’s 7,104).

So why doesn’t the Leaf put in more cells? That is partly because of the problem of charging, and partly because of price and suitability for a chosen niche. A review of electric vehicles in our local paper brought up these facts. There are statements that the 400 k type car be charged at home overnight, “just like your mobile phone”. Well, not quite. While that sounds easy enough, where are you going to do it? Your home may have a garage, so maybe there. The mobile connector comes with adaptors that permit charging at 40 amps. Um, does your house have 40 amp rating to your garage, or maybe 50 amp to be on the safe side because you don’t want to accidentally throw the fuse and be walking to wherever next morning? Our reviewer found that to fully charge such a vehicle with 400 km range using his garage power rating took the best part of two days. Using a fast charger as available here, it took 75 minutes. Yes, you can charge these batteries relatively quickly if you can deliver the required current. The reason the Leaf has such a small battery capacity is so that it can be charged overnight with the average domestic power supply, and it can also be recharged while at work if the owner can “graze” on some power supply. Needless to say, once someone published figures like that, someone else challenged them, and pointed out that a steady 7 kW overnight would do it and “nearly two days” was wrong. Unfortunately, power itself is not the whole story because the current has to be rectified and voltage has to be kept to within a specific range. Apply an over-voltage, and different chemistry starts up in the battery that is not reversible, which means you greatly shorten your battery life.

There is some good news on batteries, though. The batteries do decay with time, and while details are not available, one estimate is that Tesla batteries should still be 90% effective after 8 years, which is quite respectable, while the Leaf claims its batteries should last ten years in a workable condition. Thus we have two types of vehicles: an expensive vehicle that can do anything a current vehicle can do on the open highway, provided there are adequate rapid charging sites. Here “adequate” takes on significance; refilling with petrol takes a few minutes and sometimes there is overcrowding. Will there be enough cables if it takes 75 minutes? How much will “site time” charge?

Then there is the question of how you use it. Do you carry big loads? Ferry lots of children? Go off road, or go camping? If so, the current electric vehicle is not for you. So the question then is, for those who see the electric vehicle as all you have to do to solve the transport problem, are they advocating no off-road activity, no camping, no serious loads? The answer is probably, yes. So, do we want to give up our lifestyle? If the answer is no. are there options? Of course not everyone wants to do those sort of things, so there will most certainly be quite sizable niches that can be filled with electric vehicles. Finally, there will be one further problem: the poorer people cannot afford new Teslas, or even new Leafs. They own second hand cars and cannot afford to simply throw that investment away. The liquid fuel transport economy will be with us for a lot longer yet.

The next question is, is it feasible to replace all cars with electric vehicles? For the purpose of analysis, I shall assume everyone wants a Tesla type driving capacity, as the next step is to put numbers on the problem. The battery weight is listed as 540 kg, which means to do the replacement, we would need something approaching half a billion tonne of batteries. That is not all lithium, but it includes “a small amount of cobalt and nickel”. If we interpret that as about 2% the weight each of the batteries, we need about ten million tonne of cobalt and nickel. World production of cobalt in 2017 was about 110,000 tonne, while nickel was over ten times this. Both metals, however, are fully used now, and the cobalt supply is deficient by about two orders of magnitude if all cobalt was devoted to electric vehicles. Unlikely. Oops! That is more than a small problem. It is not a problem right now because electric vehicles comprise only a very small fraction of the market, but it is insoluble. There is a strict limit on the possible supply of cobalt because as far as I know, there are no cobalt ores. Most cobalt comes from the Democratic Republic of Congo, as a by-product of copper mining. There would also be a significant demand for copper. The Tesla has two motors, one of which is 300 kW, so considerable amount of copper would be used, but world production of copper is about 24,000 Mt annually, so that is not an immediate problem, but may be in the long term. The annual supply of graphite is 126,000 t. Given that there will be more graphite used than lithium, this is a serious problem, however there is no shortage of carbon; the problem is converting carbon to graphite. That is quite a subtle problem; as it happens I know how to get close to the required fraction of graphite, but as yet, not economically.

So there are technological problems. Maybe they are soluble, but doing so introduces another problem, as exemplified by finding an alternative to cobalt. Cobalt is needed to give the non-graphitic electrode enough strength that the battery will have adequate lifetimes with good charging rates. So that is probably non-negotiable. There are alternatives, but so far none match the current battery type used by Tesla. Further, to develop a new battery and test its lifetime over ten years takes: you guessed it; the last part alone takes ten years, assuming your first pick works. Therein lies the overall problem; politicians have wasted nearly 30 years on the basis that it was not urgent. However, technical development does take a long time. For that reason it is wrong to lazily say, electric vehicles, or some other solution, will solve the problem. They will most certainly help, but we have to back many more options.

Discount on Ebook

Discounted to 99c/99p from Oct 11 – 18: Legionis Legatus. Second in a series wherein Scaevola, on the verge of abandoning Athene’s quest, suddenly finds more of the prophecy coming true: Caligulae gives him the command of a legion; he suddenly sees why Aristotle was wrong when he proved the Earth could not go around the sun; and while doing so, he ignores the most beautiful woman he has seen, one of the only two prophesied to be in his life. Scaevola must recover from ignoring she who could be his wife, help thwart the Scribonianus coup against Claudius, and command legion XX Valeria for the invasion of Britain. A historical novel that also includes the answer to the scientific puzzle in Athene’s Prophecy: how to show why the earth has to go around the sun with the knowledge available at the time. http://www.amazon.com/dp/B00JRH83E2

Science and Climate Change

In the previous post, I questioned whether science is being carried out properly. You may well wonder, then, when this week the Intergovernmental Panel on Climate Change issued a rather depressing report, and a rather awkward challenge: according to their report, the world needed to limit the temperature rise to 1.5 degrees C between now and 2050, and to do that, it needed to cut carbon emissions by 45% by 2030, and net zero by 2050. Even then significant amounts of carbon have to be removed from the atmosphere. The first question is, then, is this real, and if so, why has the IPCC suddenly reduced the tolerable emissions? If their scientists previously predicted seriously lower requirements, why should these be considered better? There are two simple answers. The first is the lesser requirements were based on the assumption that nations would promptly reduce emissions. Most actually increased them. The second is more complicated.

The physics have been verified many times. However, predicting the effects is another matter. The qualitative effects are easily predicted, but to put numbers on them requires very complicated modelling. The planet is not an ideal object, and the calculation is best thought of as an estimate. What has probably happened is their modelling made a projection of what would happen, and they did this long enough ago that now that they can compare prediction with where we are now. That tells them how good the various constants they put into the model were. Such a comparison is somewhat difficult, but there are clear signs in our observations, and things are worse than we might hope for.

So, what are we going to do? Nothing dramatic is going to happen on 2040, or 2050. Change will be gradual, but its progress will be unstoppable unless very dramatic changes in our behaviour are made. The technical challenges here are immense. However, there are a number of important decisions to be taken because we are running short of time due to previous inaction. Do we want to defend what we have? Do we want to attempt to do it through sacrificing our life style, or do we want to attempt a more aggressive approach? Can we get sufficient agreement that anything we try will be properly implemented? Worst of all, do we know what our options are? Of these questions, I am convinced that through inaction, and in part the structural defects of academic science, the answer to the last question is no.

The original factor of required emissions reduction was set at 1990 as a reference point. What eventuated was that very few countries actually reduced any emissions, and most increased them. The few that did reduce them did that by closing coal-fired electricity generation and opted for burning natural gas. This really achieves little, and would have happened anyway. Europe did that, although France is a notable exception to this in that it has had significant nuclear power for a long time. Nuclear power has its problems, but carbon emissions are not one of them. The countries of the Soviet Union have also actually had emission reductions, although this is as much as anything due to the collapse of their economies as they made the rather stupid attempt to convert to “free market economics” which permitted a small number of oligarchs to cream the economy, sell off what they could, use what was usable, pay negligible wages and export their profits so they could purchase foreign football clubs. That reduced carbon emissions, but it is hardly a model to follow.

There is worse news. Most people by now have recognized that Donald Trump and the Republican party do not believe in global warming, while a number of other countries that are only beginning to industrialize want the right to emit their share of CO2 and are on a path to burn coal. Some equatorial countries are hell-bent on tearing down their rain forest, while warming in Siberia will release huge amounts of methane, which is about thirty times more potent than CO2. Further, if we are to totally change our way of life, we shall have to dismantle the energy-related infrastructure from the last fifty years or so (earlier material has probably already been retired) and replace it, which, at the very least will require billions of tonnes of carbon to make the required metals.

There will be some fairly predictable cries. Vegetarians will tell everyone to give up meat. Cyclists will tell everyone they should stop driving cars. In short, everyone will have ideas where someone else gives up whatever. One problem is that people tend to want to go for “the magic bullet”, the one fix to fix them all. Thus everyone should switch to driving electric vehicles. In the long term, yes, but you cannot take all those current vehicles off the road, and despite what some say, heavy trucks, major farm and construction equipment, and aircraft are going to run on hydrocarbons for the foreseeable future. People talk about hydrogen, but hydrogen currently requires massive steel bottles (unless you are NASA, or unless you can get hydrides to act reversibly). And, of course, there is a shortage of material to make enough batteries. Yes, electric vehicles, cycling, public transport and being a vegetarian are all noble contributions, but they are just that. Wind and solar power, together with some other sources, are highly desirable, but I suspect that something else, such as nuclear power must be adopted more aggressively. In this context, Germany closing down such reactors is not helpful either.

Removing CO2 from the atmosphere is not that easy either. There have been proposals to absorb it from the effluent gases of coal-fired power stations. Such scrubbing is not 100% efficient, but even if it were, it is not dealing with what is already there. My guess is, that can only be managed by plants in sufficient scale. While not extremely efficient, once going they look after themselves. Eventually you have to do something with the biomass, but restoring all the tropical rain forests would achieve something in the short term. My personal view is the best chances are to grow algae. The sea has a huge area and while we still have to learn how to do it, it is plausible, and the resultant biomass could be used to make biofuel.

No, it is not going to be easy. The real question is, can we be bothered trying to save what we have?

Is science being carried out properly?

How do scientists carry out science, and how should they? These are questions that have been raised by reviewers in a recent edition of Science magazine, one of the leading science journals. One of the telling quotes is “resources (that) influence the course of science are still more rooted in traditions and intuitions than in evidence.” What does that mean? In my opinion, it is along the lines, for those who have, much will be given. “Much” here refers to much of what is available. Government funding can be tight. And in fairness, those who provide funds want to see something for their efforts, and they are more likely to see something from someone who has produced results consistently in the past. The problem is, the bureaucrats responsible for providing the finds have no idea of the quality of what is produced, so they tend to count scientific papers. This favours the production of fairly ordinary stuff, or even rubbish. Newbies are given a chance, but there is a price: they cannot afford to produce nothing. So what tends to happen is that funds are driven towards something that is difficult to fail, except maybe for some very large projects, like the large hadron collider. The most important thing required is that something is measured, and that something is more or less understandable and acceptable by a scientific journal, for that is a successful result. In some cases, the question, “Why was that measured?” would best be answered, “Because it was easy.” Even the large hadron collider fell into that zone. Scientists wanted to find the Higgs boson, and supersymmetry particles. They found the first, and I suppose when the question of building the collider, the reference (totally not apt) to the “God Particle” did not hurt.

However, while getting research funding for things to be measured is difficult, getting money for analyzing what we know, or for developing theories (other than doing applied mathematics on existing theories), is virtually impossible. I believe this is a problem, and particularly for analyzing what we know. We are in this quite strange position that while in principle we have acquired a huge amount of data, we are not always sure of what we know. To add to our problems, anything found more than twenty years ago is as likely as not to be forgotten.

Theory is thus stagnating. With the exception of cosmic inflation, there have been no new major theories that have taken hold since about 1970. Yet far more scientists have been working during this period than in all of previous history. Of course this may merely be due to the fact that new theories have been proposed, but nobody has accepted them. A quote from Max Planck, who effectively started quantum mechanics may show light on this: “A new scientific truth does not triumph
by convincing its opponents and making them see the light, but rather because its opponents eventually die.” Not very encouraging. Another reason may be that it failed to draw attention to itself. No scientist these days can read more than an extremely tiny fraction of what is written, as there are tens of millions of scientific papers in chemistry alone. Computer searching helps, but only for well-defined problems, such as a property of some material. How can you define carefully what you do not know exists?

Further information from this Science article provided some interest. An investigation led to what then non-scientists might consider a highly odd result, namely for scientific papers to be a hit, it was found that usually at least 90 per cent of what is written is well established. Novelty might be prized, but unless well mixed with the familiar, nobody will read it, or even worse, it will not be published. That, perforce, means that in general there will be no extremely novel approach, but rather anything new will be a tweak on what is established. To add to this, a study of “star” scientists who had premature deaths led to an interesting observation: the output of their collaborators fell away, which indicates that only the “star” was contributing much intellectual effort, and probably actively squashing dissenting views, whereas new entrants to the field who were starting to shine tended not to have done much in that field before the “star” died.

A different reviewer noticed that many scientists put in very little effort to cite past discoveries, and when citing literature, the most important is about five years old. There will be exceptions, usually through citing papers by the very famous, but I rather suspect in most cases these are cited more to show the authors in a good light than for any subject illumination. Another reviewer noted that scientists appeared to be narrowly channeled in their research by the need to get recognition, which requires work familiar to the readers, and reviewers, particularly those that review funding applications. The important thing is to keep up an output of “good work”, and that tends to mean only too many go after something that they more or less already now the answer. Yes, new facts are reported, but what do they mean? This, of course, fits in well with Thomas Kuhn’s picture of science, where the new activities are generally puzzles that are to be solved, but not puzzles that will be exceedingly difficult to solve. What all this appears to mean is that science is becoming very good at confirming that which would have been easily guessed, but not so good at coming up with the radically new. Actually, there is worse, but that is for the next post.