On 28th July, I posted an essay of mine entitled The Global Crisis and Role of So-called
Renewable Energies in Solving It on this blog-site (see below). It had been
published a few days earlier in the online magazine Insurge-Intelligence as a contribution to a symposium on renewable
energies (https://medium.com/insurge-intelligence/how-clean-is-clean-energy-why-renewables-cannot-solve-the-global-crisis-10205baeb781).
Several readers responded to it with comments, both positive and negative. Prof. Mark Diesendorf, another contributor to the symposium, who had expressed views totally opposite to those of mine (https://medium.com/insurge-intelligence/the-feasibility-of-100-renewable-energy-f624d93e1424), also responded with two half dissenting and half agreeing comments.
I thought it was necessary to respond to his comments with a short article that clarifies some important issues not dealt with in my original contribution, which was limited by space. I now publish it here. See below.
Several readers responded to it with comments, both positive and negative. Prof. Mark Diesendorf, another contributor to the symposium, who had expressed views totally opposite to those of mine (https://medium.com/insurge-intelligence/the-feasibility-of-100-renewable-energy-f624d93e1424), also responded with two half dissenting and half agreeing comments.
I thought it was necessary to respond to his comments with a short article that clarifies some important issues not dealt with in my original contribution, which was limited by space. I now publish it here. See below.
Numbers, Facts and Statistics
Mark wants to know the names of the experts who doubt that the EROEI of solar energy (PV-tech.) is positive (or, I should say, positive enough to run, in future, an industrial economy). In fact, in my essay I have given reference to Ugo Bardi's article on the subject. Some references can be found there and in the discussion following it. See also Prof. Charles Hall's contribution to the discussion in http://cassandralegacy.blogspot.de/2016/05/the-real-eroi-of-photovoltaic-systems.html
I am not a researcher on the subject, but I try to keep myself informed as an interested political activist. Mark writes: "The claim was only true several decades ago, before solar PV modules were mass-produced." My information is just the opposite. In a much quoted scientific paper published in 1991 in a serious scientific journal called International Journal of Solar Energy(Vol. 10, 1991), Wolfgang Palz and Henri Zibetta wrote 26 years ago that, in European climates, the average energy payback time (EPT) for photovoltaic modules were as low as 1.2 to 2.1 years. That means their EROEI was very high. (EPT and EROEI are both measuring units for the same thing, namely net energy, expressed in two different ways. They are roughly inversely proportional). In the following years of the 1990s however, in the works of other researchers, the EPT figures for Photovoltaic modules rose, to 7 years, 9 years and 10 years – in spite of presumable continuous improvements in the technology.
I could not (and still cannot) judge the scientific quality of these research works. The point I want to make here is only that, in the 1990s, it appeared and it still appears to me that a lot of arbitrary calculating methods and perhaps also bias of the researchers were responsible for this chaotic results. So when Mark writes that, nowadays, the EPT of PV solar modules is typically 1 – 3 years, I cannot accept it as correct, simply because Mark says it. So I tried to apply my own non-researcher faculty of logical thinking, the result of which I have presented in my essay. In the 1990s, to my knowledge, no researcher was taking the energy invested in back-up power stations into account.
Mark gracefully agrees with my assertion based only on logic that the EI figure of all and any industrial product (hence also of PV modules, wind turbines, bicycles, toothpaste etc. etc. etc.) is bound to continuously increase because of continuously increasing remoteness of new mines and wells and continuously increasing difficulty in extracting non-renewable raw materials and raw energy-materials (coal, oil, gas, uranium) from them. But then he makes his argument incomprehensible by saying, "This is indeed a strong limitation on the continued production of fossil fuels, but is irrelevant to renewable energy resources: sunshine, wind, etc." Haven't I distinguished in my essay between the sources of energy sunshine and wind from the equipments (PV modules, wind turbines etc.) for producing electricity from sunshine and wind? For the EI of the latter, i.e. the equipments, the difficulties mentioned above are indeed very relevant. Their EI is continuously increasing and hence (it is simple arithmetic), ceteris paribus, the EROEI of solar and wind electricity systems must be continuously diminishing. This generally happens also to fossil and nuclear energy systems and their EROEI.
In statistics, there are many things that cannot be measured satisfactorily and are therefore open to bias of the researcher or the client. Opinion researchers e.g. can never know whether the respondents to their questions are telling the truth. But also actually measurable things like GDP, unemployment rate, total work force, inflation rate, cost of living, poverty rate etc. can be distorted because of varying definitions and/or wrong counting methods such as having too small a sample or the sample being unrepresentative. This fact gave rise to the bon mot "I do not believe any statistics other than those I have myself falsified."
Hopes for the Future
Mark writes: "… energy technologies are made increasingly by using renewable energy." I have heard of a solar panel factory in Freiburg, Germany, (not a big one, maybe an experimental one), that derives all its energy from the solar panels installed on the roof terrace of the factory. Supposing the information is true, it does not prove Mark's point. The four questions put by foodstuff (I only quoted him) are not answered with this example (please read the four questions once more!). Mark himself gives two examples – "A mining company in remote Australia is currently building a solar farm to substitute for most of its prolific diesel consumption, and the Tesla gigafactory for manufacturing batteries will be completely powered by RE." In the first example, the machines in the factory are using electricity from solar panels; my informant did not say that they are being built by means of electricity derived from solar panels. In the second example (given by Mark himself) solar electricity will only substitute diesel consumption. The huge machines used by the company for mining activities will not be built with the help of solar electricity. In the third example, the batteries will be built by using solar electricity. Tesla is not claiming that the gigafactory itself or the machines for manufacturing batteries will be built by using solar electricity. And if one enquires a little further, one may find that in the second and third case, the solar panels, subsidized by the state, have been manufactured in China using dirty coal-electricity. Reg. the case of the factory in Freiburg, I know that all the 6 major German solar panel manufacturers have gone bankrupt.
Basing himself on the examples he has given, Mark thinks that "… although the current generation of RE technologies is being made mainly by using fossil energy, the next generation will utilize RE to a greater degree and so on until RE systems are made entirely by using RE." At another place he writes, "The energy for mining the raw materials and building the RE hardware can in future be renewable and this transition has already begun." I am not convinced that the end result of this transition will be the much touted 100% RE for the whole industrial economy. Because Mark does not say with what kind of energy the mining machinery/hardware, the huge trucks, the caterpillars etc. will be built. On the whole, his hopes appear to me as pure faith in miracles happening in future, wishful, not rational thinking. Wishful thinking is an obstacle to making rational/realistic political decisions.
The Second Law of Thermodynamics (Entropy Law) and Some Favorite Illusions of RE Enthusiasts
Mark writes: "… there is no contradiction between the Second Law of Thermodynamics and a global 100% renewable energy (RE) system, so long as the Sun continues to shine." I am not sure I have understood in which sense exactly he has written this. But it sounds like saying there is no contradiction between faith in a good and almighty God and the fact that there is evil in this world, no contradiction between the Genesis story of the Bible and the Evolution theory of Darwin. Polemic apart, Mark seems to forget again and again the distinction I made between sources of energy and equipments of energy. Logically and plausibly, we may argue that humanity will exist on the earth so long as the Sun continues to shine. But we cannot say that the industrial society can continue to exist without the fossil fuels and nonrenewable materials.
I am not an engineer, not one of those who are expected to know the Entropy Law. Yet I was compelled to learn the essence of this law. During a private discussion on future energy and resources shortage, an economist said (in the general sense): I do not understand why availability of oil and minerals should be a problem; science says nothing gets lost in this universe. That was obviously the First Law of Thermodynamics or the law of conservation of matter and energy. So let us recycle everything, all problems solved. A friend of Johnny Rutherford, an RE enthusiast, once said, soon the whole industrial economy would run without having to extract a single molecule more. To lay public it may seem plausible. For, after all, the Sun sends us15 000 times more energy than all the commercial energy we need, for free. I am a bit surprised that Mark has not suggested this "solution" for all non-renewable resources. But why can't we recycle everything? Because there is a contradiction between 100% recycling and the Entropy Law.
I have learnt that in the process of being used in any production process, all energy and materials get dissipated, more or less. Some part of it gets lost, that is, becomes unrecoverable. From the state of being available, part of the materials used in production goes over to the state of being unavailable. In pure theory, of course, the whole quantity could be recovered and brought back to their original available state, but only if we are prepared to spend enough energy and materials for this work. In many cases, this process is, in energy and material terms, too costly to be economically viable at all. Again, it may be feasible but not viable. This explains why in real industry not everything is even attempted to be recycled.
Energy recycling is practically impossible. A quantity of coal, gas, or petroleum, once burnt, cannot be recycled, although the hydrogen and carbon atoms are not lost, although they still exist somewhere in the atmosphere or the earth. They are however so strongly dissipated that recycling them is only possible in a laboratory by using immensely more energy than what can be recovered. Lack of knowledge or understanding of the Second Law of Thermodynamics may lead some people to cherish the illusion that, as commenter Mark Goldes writes, "24/7 cheap green energy is being born. Engines designed to run on atmospheric (ambient) heat instead of fuel. Ambient heat is a huge untapped reservoir of solar energy available everywhere around the clock." There would be "no combustion" in such engines.
Another commenter, John Weber, who agrees with me, referred to the many high temperature processes required in an industrial economy, especially in metallurgy and glass industries. Now rays of the Sun reach us in a high entropy (i.e. highly dissipated) state. This is why we have to spend a lot of energy and materials to first collect and convert them into electricity before we can use them. If we want to use them in metallurgical furnaces, we have to concentrate them further to a very much higher temperature (strongly low entropy state). And at every stage of collection and concentration, in every process of conversion (e.g. to liquid hydrogen), and in the process of every piece of work done, some energy is inevitably lost, i.e. dissipated without being used. That solar modules have a lifespan of 25 years, does not help much in overcoming these problems.
These are essential points of our controversy. I hope Insurge-Intelligence readers would read also this contribution of mine with interest.
