Thursday, June 23, 2016

Brexit: requiem for a dream

For many years, I had thought that a united Europe was a great idea. An institution created by wise men who had wanted to avoid repeating the horrible mistakes that had led Europeans to massacre each other in two terrible wars. Europe was supposed to be a Europe of the people, a force for peace, for  justice, for equality, for the defense of both humankind and nature.

Two years ago, I was in Brussels for a hearing at the European Parliament; it was a shock. The Europe I knew, the Europe I thought I knew, wasn't anywhere to be found. What I found was a bunch of ill-advised, pompous bureaucrats wandering in a gigantic and useless palace. The ghosts of the founders had been thoroughly exorcised and now what was left was an empty shell; a structure that just perpetuated itself without any clear purpose, except drilling more fossil fuels out of the ground, and - maybe - make war to Russia. The dream of a Europe of the peoples acting for peace and justice was gone. Requiem for a dream.

And now what? It seems clear that Europe, as it is now, cannot survive this blow and maybe this is not a bad thing. Can we reform this Europe? Or can we restart from scratch? Impossible to say. In any case, here is the post that I wrote two years ago after my trip to Brussels. If you can read Spanish, you may be also interested in these considerations by Antono Turiel.


Bringing the message about resource depletion to the European Parliament

With 24 languages deemed as "official," the European Union shares some characteristics with the ancient Babel Tower (above, the parliament building in Strasbourg). The Babel of languages is one of the problems associated with trying to pass messages to politicians, but not the most important one. Rather, the main problem seems to be a decisional mechanism which favors groupthink Here are some notes of a recent experience of mine at a hearing on energy security of the European Parliament in Brussels.

As I walk to the hearing on energy security in Europe, I am struck first of all by the size of the hall. The "Alcide De Gasperi" room in the palace of the European Parliament in Brussels was clearly built for impressing people, in addition to its function as a meeting room. One of its most remarkable features is the long row of windows of the interpreters' rooms. Since there are 24 official languages of the European Union, there have to be some 50 interpreters working in there. Then, I also notice how the screens for projecting one's slides are small and located high up, near the ceiling. This is not a place where you are supposed to support your statements with data and graphs. It is a place built for political debate.

As people collect in the hall, I can see that the atmosphere is rather formal, with several members of the European Parliament sitting in the audience. Most people are dressed in suits and many wear ties. On the podium, there are six invited speakers. And there we go; I immediately sense the mood of the conference: this is not a scientific meeting. None of the speakers seem to be an expert about fossil fuels, intended as markets, production, resources, reserves, and the like. Rather, they seem to be mainly concerned with strategic and political issues. The line that emerges from the presentations and from the reactions of the audience is clear: it is a highly confrontational attitude (to put it mildly) toward Russia, accused to be engaging in an economic war against Western Europe. The gist of what I hear is that the European Union must unite in defense; we must follow the example of the United States and get rid of our silly regulations and of the local resistance against drilling and nuclear plants. Europe can exploit its shale gas and oil resources (and also nuclear energy) and attain energy independence, as the United States did. It is "drill, drill, drill" all over.

This line, in various shades, is the position of four speakers out of six. The bias in favor of fossil fuels is shown also by the fact that the lady charged with defending renewables is given the last time slot of the hearing. The fossil oriented attitude seems to be shared by the majority of the audience. Not that it is not challenged by some of the MEPs in the room. One of them (I know him well, he has been a long time ASPO supporter) stands up and tells to one of the speakers: "it is not true that the United States has attained energy independence. You have to stop getting your data from newspapers!". He is right, (you can look at the data yourself). But it is an isolated reaction, and the overall debate remains based on the idea that the US has become energy independent or that, at least, it will soon become independent.

When it is my turn to speak, I tell a different story. I try to explain that the ultimate origin of the energy security problems in Europe is due to depletion, and that drilling more is not the solution. I keep the message as simple as possible; tailored for people who are not specialists in oil and gas. I show the price trends, I tell them something about energy return, and I make the point that renewable energy is not subjected to depletion. I sense that my talk is well received: the people in the audience listen to what I say, and they look up at my slides (but those screens are too high and too small, dammit!). I also get several questions and comments - mostly favorable ones. After the hearing is over, several people stop me to discuss further about what I said. As a talk, it was a reasonably successful one.

But, on the whole, I think I had a very modest impact, if any. As I noticed many times, it is extremely difficult to pass to decision makers messages which are perceived as out of the ordinary, as the message on resource depletion is. The problem has many facets and it has to do, mainly, with the way politicians think. According to my experience, politicians - especially high level ones - are very smart people. The problem is that they are swamped with information; just as most of us. So, in the great mass of data arriving, how do you decide what is the truth? If you are a scientist - or you are scientifically trained - you have ways to evaluate the data and filter out the bad ones. But politicians are not scientists, they are not scientifically trained, so they use a different method. They maintain a healthy dose of skepticism about everything they hear; they don't pay too much attention on data, and they tend to side with the interpretation that they perceive as the most compatible with the general opinion of the group they belong to.

There are reasons for this "groupthink" syndrome that, probably, affects politicians more than most of us. It is because then main tool in the political struggle, today, is the demonization of adversaries. So, a politician is very careful to avoid to be singled out from the crowd of colleagues and subjected to the standard demonizing treatment. For a politician, there is safety in crowds; a traditional strategy well known also by sheep and fish. In practice, you may see a politician as having a built in opinion detector in his head. He/she will sense the position of the majority and try to avoid straying too far away from it. In general, the way for a politician to obtain power is to occupy the center; to be seen as a moderate. That this is the way to success has been known for a long time; even rigorously modeled (in economics, it is known as the "Hotelling's law"). Scientists are sometimes contrarians, politicians almost never are.

So, I think I can figure out the reaction of most of the MEPs to the hearing on energy security in Brussels. It was something like, "Well, that Italian guy who spoke about resource depletion might have a point about what the real problem is. I couldn't his slides so well, so high up near the ceiling, but he seemed to have some good data. But, on the other hand, the other speakers saw the problem differently. If most people in the parliament think that Russia is waging an economic war against us and that drilling more is a good idea, then there has to be something in it. For sure, I shouldn't take the risk of siding with a minority option."

Ugo Bardi teaches at the University of Florence, Italy. He is a member of the Club of Rome and the author of "Extracted, how the quest for mineral wealth is plundering the planet" (Chelsea Green 2014)

The end of the "population boom": the Seneca collapse of Ireland's population during the great famine

The story of the Great Famine in Ireland is a starkly clear example of a "Seneca Collapse", that is of a case where decline is much more rapid than growth. Is something in store for us at the global level? (Image source Rannpháirtí anaithnid (old) at English Wikipedia)

In a previous post, I argued that many current global population projections are mistakenly based on the idea that the "demographic transition" will work backward. That is, it is often assumed that impoverished people will tend to make more children and that, therefore, the world's population will keep growing even in the midst of the profound economic decline that could accompany a resource and climate crisis. (this is, for instance, the assumption of the original "The Limits to Growth study in 1972)

I proposed, instead, that the start of a major economic/climate crisis will cause an immediate reduction of the birth rates in part as the result of the declining health of fertile women and, in part, by a rational response by families who would understand that they can only care for a limited number of children in a condition of increasing poverty.

That is, there won't be a population increase in the midst of a major crisis and the decline of birth rates would immediately bring the start of a worldwide population decline that could even take the shape of a true "Seneca Collapse." To support my argument, I brought the example of the Soviet Union, whose population started declining even before the political collapse of the Union. I also mentioned several examples of other Western Countries (e.g. Italy) where birth rates have been going down in parallel with the worsening of the economic conditions, to the point that we are starting to see an overall population decline.

This interpretation was criticized in the comments by some who argued that, yes, my interpretation may be correct for relatively modern and "Westernized" countries, but not for the poorest areas such Africa or Asia. These commentators argued that people in these areas will continue to make as many children as they can, no matter what happens around them; apparently as a result of the Imams telling them to do so (or by evil dictator Erdogan, or the like).

I don't think this criticism is correct and I can counter it with an example. We all know the story of the Irish famine that took place between 1845 and 1852, and that killed a large fraction of the Irish population. We know something about the number of deaths, about how many Irish emigrated, but we know relatively little of how the famine affected birth rates. Did Irish women try to compensate for the higher mortality by having more children?

On this point, I found a comprehensive study produced by Phelim P. Boyle and Cormac O Grada on Demography, Vol. 23, No. 4 (Nov., 1986), pp. 543-562 (here is the link). It takes some assumptions and extrapolations to determine the Irish birth rates before and after the famine. They also do not report graphs, but only tables. However, their conclusion is clear: birth rates declined with the famine in Ireland. In other words, the Irish families didn't try to compensate for the higher mortality by having more children; not at all.

This is confirmed by what we see of the Irish population in the decades after the famine. Even though food supply ceased to be a problem, still the population continued to decline or remain stable well into the 20th century. The Irish of those times didn't have good contraceptives, but they seem to have coped mainly by retarding the marriage age and by adopting a lifestyle that discouraged sexual activity among young people.

This is relevant for the case I am discussing here. In the 19th century, the Irish peasants were Catholic (or, if you prefer, "Papists"). The catholic view of marriage was supposed to be at that time (as it is still today in some circles) that a married couple should have as many children as the Lord sends them - that is as many as possible. After the famine, the Irish remained Catholic, but they totally disregarded the advice that the may perhaps have received from their priests. It was a perfectly rational choice - the Irish were not stupid.

We are clearly discussing something difficult to quantify, but I tend to think that most people on this planet are not so stupid as PR specialists seem to believe. So, from these historical examples (Russia and Ireland) I would say that a future economic/climate crisis will be immediately accompanied by a decline in birth rates and, hence, of population. If that happens, it will be a good thing as the pressure on the ecosystem will be reduced. That doesn't mean that all the problems we face will be solved, but at least we don't have to worry that people will worsen the situation by breeding like rabbits.

Monday, June 20, 2016

The end of the "population problem"? Another Seneca cliff in our future

Image from "National Geographic"

If the demographic projections by the United Nations will turn out to be true, the world population should reach over 11 billion people by 2100. Some think that it will be a disaster, others see it as a good thing as it would bring more economic growth. But is it really possible to reach such numbers? Can we really think that women would be so stupid to continue making children even in the midst of the crisis caused by declining natural resources and worsening ecosystem disruption? (unless the Pope himself were to tell them to stop)?

Yet, some models tell us the human population could keep increasing even after the collapse of the world's economy. There exists something called the "demographic transition" and it is a historical observation that may be extrapolated into the future. The data show a sort of "U-shaped fertility curve" that makes the poor and the very rich to be more fertile than those who are in the middle. When applied to the scenarios of "The Limits to Growth" of 1972, this idea generated a curious behavior, with the impoverishment of the population causing an increase in the birthrate that causes the population to continue increasing for a few decades after the collapse.

But, as it is always the case, extrapolating past trends into the future is extremely dangerous. In particular, it is at least improbable that the post-collapse world will be like running the same movie in reverse. The demographic transition has been observed to occur in growing economies, it won't simply change sign and reverse itself in contracting economies. To see how it works we can look at the demographic trends in Russia.

The increase in the death rate among Russians was not compensated by an increase in birth rates, as the demographic transition model would say. Russian women and Russian families reacted to a difficult situation by postponing or avoiding to generate new children, correctly understanding that these children would face very hard times and that it would have been impossible for their families to support them. Note the rapid collapse of birthrathes, a true "Seneca Cliff."

Now, I have a highly positive opinion of the intelligence of Russian people and, in particular, of Russian women. But I just can't think that people in other regions of the world would behave very differently. Those who maintain that people will make more children as they become poorer seem to assume that most people, and women in particular, are not more intelligent than an average rabbit. But, as it is always the case, extrapolating past trends into the future is extremely dangerous. While is true that most people are not very effective at the task of acting in order to benefit humankind as a whole, most people are perfectly able to understand what's good for themselves and their immediate families. And, in times of trouble, they normally react by planning in order to optimize the number of their surviving offspring. Humans apply what's called the "K-strategy" in reproduction: they concentrate the resources available on fewer children in order to maximize their probability of success.

Of course, we are dealing with phenomena of which we know little. After that the world's economy peaks, all the bets are off. But it may not be a coincidence that whole regions of the world, such as Southern Europe have started a population decline, despite having traditionally been demographically active. Among these GreeceItaly, Spain, and Portugal. Outside Europe, Japan has also started to decline, inverting a tendency of growth that had been ongoing from the 1920s. It is not yet possible to say if these inversions are to be understood as long-term trends. But, if this is the case, they are evidence that an economic crisis has nearly immediate effects on population.

A global population decline would have at least a positive effect in the sense that it would reduce the threat of climate change and the pressure on the ecosystem. But it may turn out to be a disaster if we enter the rapidly descending slope that I called the "Seneca Cliff". Will that lead to the "near term human extinction" that some think as a likely future? It cannot be excluded, but it is also true that there may be life on the other side of the cliff if we are smart enough to understand the future. It is up to us to prepare for it.

Saturday, June 18, 2016

If Switzerland had a Sahara Desert, it would be a small Africa. Does the world really have an "overpopulation problem"?

It is already politically charged to deal with such issues as oil depletion and climate change but, at least, these are physical problems that we can examine using the scientific method. But overpopulation? That's the recipe for an instant politicized or religious quarrel.

The movie "Population Boom" by Werner Boote is a good example of how politicized and emotional the population question can become. It starts almost immediately with a potshot at the Reverend Malthus, accused to "have predicted a catastrophe for 1860" (something that poor Malthus never said.). Then, it goes on for one hour and a half in the attempt to demonstrate that there is no such a thing as an "overpopulation problem." Rather, the film's thesis is that the world is seeing a conspiracy by the elites of the rich countries who are trying to stop the people in poor countries from having as many children as they want so that they could become rich, too, and challenge the world dominance of the present elites.

If we accept the idea that all opinions are legitimate, then also this one should be - even though probably a bit too extreme for most of us. The problem is that the way the film tries to demonstrate its thesis oscillates between the boring and the silly; without ever providing a serious argument. Mainly, we see the filmmaker, Mr. Werner Boote, walking around while carrying his umbrella in places where it never seems to rain. In his ramblings, Mr. Boote interviews people who, frankly, don't seem to have a clue about overpopulation, except for seeing it as an invention of the evil Western Elites (and the same is true for global warming, explicitly defined as such in one of the interviews).

Most of the arguments made in these interviews are so silly that they are not even worth deconstructing. Just as an example, in a scene we see Mr. Boote (for once without his umbrella) discussing with a man who tells him that Africa is not overpopulated because it has only 40 inhabitants per square km, compared with the 170 of Europe. Then, the man takes Boote somewhere and he shows him an empty landscape, saying, "do you see? Africa is not overpopulated!"

Now, there are several problems here. The datum for the population density in Africa seems to be correct, but the population density in Europe is 105 inhabitants per square km, not 170 (and it is just 31 if one includes Russia.). Maybe Mr. Boote's informant meant Western Europe, but if you take that as meaning the European Union, then the population density still is only 116. Then, one would be tempted to remind to Mr. Boote's informant that Europe doesn't have a Sahara desert; to say nothing about the Kalahari desert and other areas unsuitable for human occupation in Africa. So, he conveniently forgets that an African country such as Nigeria has about the same density of population as Switzerland (nearly 200 people per square km), to say nothing about Rwanda, that has 460 people per square km (more than twice than Switzerland). Finally, one could show to Mr. Boote and to his informant the Yosemite valley or the Death Valley and then tell them: "you see? Almost no one lives in California!

I could go on, but I think this is enough for this movie. Let me just add that if you think that the poor do not pollute the ecosystem, you would do well reading this post by Jacopo Simonetta.

Thursday, June 16, 2016

Social Equality and the Destruction of the Planet

In this post, Jacopo Simonetta asks a fundamental (and politically incorrect) question: are we sure that social equality would be good for the environment? The answer turns out to be not politically very correct. (U.B.)

by Jacopo Simonetta

Exaggerated inequality is surely a major problem in today's societies, and it keeps increasing. I, too, certainly believe that this scandal must end, but the topic of the article is another one: is it true that redistribution of wealth would have a good effect on the Earth health? Many very influential people believe this, but I am not so sure.

Evidently, affluent people consume much more than poor people do, but how much? As far as I know, there are no studies correlating the environmental impact and social classes but, as starting point, we could compare how CO2 emissions change with income. (data Word Bank and Wikipedia respectively). 


Social equity and consumption: Comparison between per capita income (in blue) and CO2 emissions (in red).

It is clear that CO2 emissions increase with income, but less than proportionally in the central part of the curve. In fact, in very low incomes, the increase in emissions is very fast against modest increases. Then they go up rather slowly, to return to peak with the very, very rich people. Important local fluctuations are also correlated to climate, geography, local traditions, social organisation and so on.

Now, as a mental exercise, we can take for good the statement that 1% of the global population appropriates 50% of world income. This means that about 75 million people earn an average income of 500,000 $ per capita per year. So, let us imagine that we can distribute all this wealth among the remaining 99% of the world population (let's call it "Operation Robin Hood"). This means more or less 5,000$ per capita. Even for a large part of the western middle class, this would be a big help. For the majority of people this would drastically change one's life. Billions of people would finally eat to satiety, dress decently, live inside houses, send their children to school, heal the sick and much more. People a little higher in the income ladder could get a new car, go on holidays, and so on.

Very good, but what would be consequences for the planet?

Let's try to analyze the question. As a rough approximation, we can start classifying humanity in four meta-categories: the very rich (let us presume they are 1%, so about 75 millions); the affluent (let us presume 1 billion people); the Middle class (according to "The Economist", about 3 billion people); the poor (may be 2 billion), and the very poor (according to FAO, about 1 billion).

Comparing per-capita income and emissions in different countries, and assuming that there are all the social classes in each country, we can argue that the very rich produce about 20 tons of CO2 each per year. The affluent 10 tons each; the middle 6 tons each, the poor 2 tons each, and the very poor 0,1 tons each. For a total amount of about 36 billion tons of CO2. “Operation Robin Hood" would lead to disappearance of the lower class and a perceptible improvement in the life style of the poor and the middle class. At the same time, also the super-rich would disappear, while nothing would change for the affluent people.

And what would that mean in terms of total CO2 emissions? Well, we just multiply the per capita emissions by the total number of people per category. The result is a grand total of about 55 billions tons, that is a 50% increment with respect to the present emissions. Social equality doesn't seem to be so good for the planet.

But there is more: Operation Robin Hood would produce a sensible reduction in mortality, and probably an increment in natality too, among low wage people. So a sharp population increase, at least for one or two generations.

Evidently, that's just an example, not a realistic simulation. But the core conclusion, that a better life for the majority of people would be disastrous for the planet, is consistent with more sophisticated models available. In the 2004 edition (Limits to Growth: The 30-Year Update), the Meadows group published a scenario where they supposed that since 2002 the birth rate is 2 children per woman and industrial production is equally distributed to everybody at a level 10% more than the global mean in the year 2000. It means much less for rich people and much more for the poor.

Word3 scenario with birth control and equal distribution of goods.(From Meadows et al. 2004)

Skipping the details, we can see that in this scenario there is a period of abundance that lasts some 20 years more than it does in the basic scenario (Business as Usual). But later the system collapses in a very similar way. And note that none of the people asking today for a more equal wealth distribution don't want any sort of birth rate control. We have no published scenario of what the outcome of these hypotheses wold be, but is not hard to argue that with a growing population andntemporary wealth distribution the system would collapse very quickly.

Another model that's relevant to our topic is "HANDY, From a scientific perspective this model, derived from an ultra-famous one by Lotka and Volterra, is too simplified to represent a system as complex as an advanced society. In particular, it neglects feedbacks existing between hierarchy, social complexity, specialization and the capability of the societal system to absorb low entropy from the outside. Unfortunately, this is one of the core feedbacks which shape the evolution of human societies. This largely reduces the viability of the model and explains the absurdity of some of the scenarios proposed. Anyway, "HANDY" has the merit of being the first model to try to introduce the social element inside a dynamic model. Here are some of the results of the model.

The above result is rather absurd since it implies that the elites keep growing even after the commoners have collapse. However, on the whole, the results of this model can be seen at least as the indication that a low level of inequality tends to shape more stable and resilient societies. In my opinion, a cursory glance at history seems to confirm this hypothesis. It is consistent also with what we have said before and with Word 3. A low level of inequality produces a more cohesive society and a highly legitimate leadership which tends to lower and to extend the peak phase of a society.

But, and this is the point, social equality is not sufficient to avoid systemic collapse if society is based on non-renewable resources.

After all, we have already seen all of this in the real world. Please observe the curves of USA and China CO2 emissions from 1990 and 2010.

The US economy trudged along with a low GDP increase completely concentrated in the top class, with a deterioration of the life level in the middle and low classes. The result has been a modest reduction in emissions.

In the same time, in China the life of the large majority of people improved and emissions skyrocketed. Because of that, the population too increased, in spite of a low birthrate. Just imagine to duplicate the China experiment: do you really believe that the Planet will survive?


It is true that billionaires are rich and I am not; this makes it possible that they are greater experts than me about money and power. But, nevertheless, it seems to me that, historically, smart leadership have always managed to redistribute a part of their revenue in ways useful to consolidate their legitimacy and hence their political power. It means that a partial redistribution of incomes would be to the advantage, first of all, of the top class people. But this is a lesson that the present day élite, largely consisting of pirates and sociopaths, has apparently forgotten.

Secondly, such action surely would improve the life of the poor, but just for a short time because, if done worldwide, the experiment would end in an unimaginable global catastrophe. Does this mean we have to be thankful to our kleptocrats? I don't believe so. It means that the reduction of inequalities must be done by reducing the income of the very rich and not by improving the commoners' wages. But this perspective is refused by everyone: right and left, south and north, up and down.

For this post I warmly thank my friend Miguel Martinez who corrected my limping English.

Monday, June 13, 2016

Will Renewables Ever Replace Fossils? The Results of a New Survey

The readers of "The Doomstead Diner" are very skeptical about the possibility of a rapid transition to a 100% renewable powered world. 54% of them say that it is impossible. 

A few weeks ago, I posted on "Cassandra's legacy" the result of an informal survey among experts in renewable energy. I asked about the chances of a transition to a world that would be completely powered by renewable energy, and about the chances of being able to attain that before climate change becomes a true catastrophe. Out of some 70 respondents, the large majority was of the opinion that a fast 100% renewable transition is possible and that can be attained without the need of heroic efforts.

I must confess that I found that result surprisingly optimistic, probably because I tend to frequent rather doomerish circles (and note the name of my blog!). Indeed, the people who read doomer sites seem to be even more pessimistic than me. So, "Reverse Engineer" of the "Doomstead Diner" ran the same survey with his readership, finding completely different results. In the Diner's survey, some 250 people participated and 54% of them said flatly that the renewable transition is impossible.

So, what can we say about these surveys? An obvious observation is that reality will decide what's going to happen about the renewable transition without paying too much attention to what puny human beings think. However, there are a few points that may be worth remarking.

1. The optimism of the experts should be considered as something more than just the opinion of the general public. Here, it is clear that the experts have a direct connection with the progress of the field and they perceive the rapid growth in efficiency and the reduction of costs. They are seeing a glimpse of hope.

2. The strong skepticism of the doomers shouldn't be discounted as a fringe opinion. It is an attitude that pervades society and that is not due to ignorance since the respondents to the Diner's survey reported a high level of formal education. However, that didn't shield them from believing in some of the various legends pervading the web. For instance, one respondent said, " All Electric RE require >70 elements of the periodic table. And they are NOT RENEWABLE."

3. The greatest shortcoming of renewables according to the doomers is their intermittency. That is a little strange, and it indicates how most of us tend to think in the BAU frame only. People are accustomed to have electricity "on demand" and won't consider the possibility of a world in which the supply is "demand managed."

4. The majority of the doomers indicated that the best renewable source is human slave labor. That's not surprising; after all, they are doomers!

5. It is refreshing, however, that only 2% of the doomers indicated that they believe that homo sapiens will soon go extinct.

There are a lot of details that you may find interesting in the survey published on the Doomstead Diner. But I would like to conclude this post with a personal note. It is something that I was telling to RE (Reverse Engineer) yesterday. I find that I am becoming less doomerish than I used to be. I can't really say why, but I think I see a chance.  Just a chance, and that won't save us from crashing against the limits of the ecosystem. But, with a little luck, we will emerge into a new world, better than the present one.

Saturday, June 11, 2016

Photovoltaic is an Energy Source, not a Sink!

This is a comment by Luis De Souza on a recent paper by Ferroni and Hopkirk who reported a negative energy yield for photovoltaic plants in Switzerland (in other words, an energy return, EROEI, smaller than one). It is an anomalous result, considering that a comprehensive meta-analysis of the field reported values of 11-12 for the EROEI of the most common PV technology. So, what's wrong with the paper by Ferroni and Hopkirk? A lot of things, it seems. Here, De Souza shows that photovoltaics is a source of energy, even in a not so sunny country as Switzerland. He concludes that something went badly wrong with the review procedure with the journal that published the paper by F&H, "Energy Policy". That seems to be correct and you may be interested to know that an extensive rebuttal of that paper has been prepared and submitted to the journal by a group of researchers expert in the field of energy calculations. That rebuttal finds a lot more wrong things in F&H's paper than those identified by De Souza. In short, Energy Policy managed to publish a flawed study that should never have been published in a scientific journal. Unfortunately, it was done and now a lot of people are using it to support the war against renewable energy.

Photo-Voltaics is not an energy sink in Switzerland

by Luis De Souza

Energy Policy recently published a study conducted on the EROEI of Photo-Voltaics (PV) technologies installed in Switzerland. The end result is a remarkably low figure of 0.8:1, well below any EROEI assessments ever conducted on this energy technology.

Such a figure naturally made the delight of those campaigning against renewable energy, who take at face value any hints of negative performance. However, from this study a number immediately stands out: average lifetime energy yield of 106 kWh/m2/a. As it turns out, a closer look at this single figure is enough to disprove the hypothesis of PV being an energy sink in Switzerland.

Basic check

The first check one can conduct on this EROEI study is to compare it with previous assessments. Pedro Prieto and Charles Hall produced what is possibly the most conservative EROEI study on PV, concluding on a figure of 2.4:1 for Spain. There is much to question in this study, in particularly the arbitrary translation of non physical requirements of a PV system into energy inputs, but for the purpose of comparison let this low figure be taken at face value.

Yearly solar radiation at the latitude of Madrid (40 ºN) is in the range of 2 000 kWh/m2. At the latitude of Bern (47 ºN) this value is down to 1 500 kWh/m2. Assuming the extraordinarily high energy inputs computed by Prieto and Hall for Spain also apply to Switzerland one can directly apply the rule of three to compute an EROEI figure of 1.8:1.

Mind here that EROEI is a logarithmic measurement. Therefore 1.8:1 is considerably closer to 2.4:1 than to 0.8:1. These simple figures start showing that something is fundamentally awkward with the results presented by Ferroni & Hopkirk.

Why energy per unit of area?

The article in itself is not very detailed and leaves much for the reader to guess. However, there is a key figure that plays into this EROEI study that immediately stands out: an average lifetime energy output of 106 kWh/m2/a for solar panels installed in Switzerland. Upfront, it appears a strangely low figure, but there is something more problematic with it. Each solar panel model is designed and built differently, with cells distributed in different ways; even among those produced by the same manufacturer the capacities per unit of area can be quite different.

The graph below shows capacities per unit of area for different models presently on sale by various manufacturers, including the world's top three.

While Ferroni & Hopkirk never indicate what energy output per installed capacity they use, this sample of panel capacity per unit area allows for some investigation into it. The figure below presents this calculation for these same panel models. 

Again, the figures vary widely, with the average under 700 Wh/Wp/a.

Comparison with PVGIS

PVGIS is a web application developed by the Joint Research Centre (JRC) that calculates the energy output of a PV system taking into account yearly solar insulation, panel orientation and system losses to cabling, the inverter, temperature, angular reflectance and more. PVGIS has not been updated in a few years and for the most recent systems I have been involved with it underestimates first year output by 5% to 10%. But for this exercise its results are taken at face value.

The table below is the result produced by PVGIS for an hypothetical system rated at 1 kWp, optimally oriented and installed around where I live, in the Canton of Zürich (47 ºN, in the Northwest of Switzerland). The most relevant figure in this report is the energy output estimate: 1090 Wh/Wp/a. While this is an estimate for an optimally oriented system, it provides a good measure of where the annual energy yield figure used by Ferroni & Hopkirk actually lays. 

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Comparison with Swiss statistics
Ferroni & Hopkirk cite the statistics compiled by Swiss Federal Office of Energy (SFOE) as the source of their 106 kWh/m2/a figure. There are a number of different documents available from theSFOE website covering all matters of energy generation and consumption.

In recent years the SFOE has produced a yearly report of renewable energy with a series of important figures. The report for 2015 is not available yet, therefore the figures used here refer only up to 2014. These are all aggregate values, but are already enough to provide another investigation path into Ferroni & Hopkirk's figure.

After going through these reports, one thing becomes evident: the SFOE does not use the energy output per unit area measure cited by Ferroni & Hopkirk. As expected, average electricity generation figures are rather provided in energy output per installed capacity (Wh/Wp/a).

Secondly it is important to note that PV is something relatively new in Switzerland, installed capacity has picked up only recently, almost tripling from 2012 to 2014. At the end of 2014 there were 1060 MWp of PV panels installed in Switzerland, a figure that grew 40% that year alone. During 2014 electricity generation from PV reached 841 GWh.

Assuming that all the new systems installed in 2014 were connected to the grid on the 1st of January a figure 794 Wh/Wp comes out for the year. This is already on the high side of the possible generation per installed capacity figures used by Ferroni & Hopkirk. However, assuming that these new systems where connected to the grid at a regular pace throughout the year, this number rises to 927 Wh/Wp. This is less than 15% off the PVGIS estimate, and possibly explainable by non optimal orientation of some systems and a small fraction of older and likely less efficient systems. Usually, systems tend to be installed towards the end of the year, to take up the most favourable legislative framework.

Possible causes

The first cause that comes to mind for such low energy yield figure is an erroneous cell efficiency factor. PV cells are rated in control experiments where their energy output is assessed at a temperature of 25 ºC and a constant radiation of 1 kW/m2. This assessment is very useful to compare different cell technologies. Modern day wholesale crystalline cells reach efficiency factors between 14% and 16%, i.e. they convert that fraction of incident radiation into electrical current.

Since Ferroni & Hopkirk present average lifetime yield in energy per unit area, these authors might have converted incident radiation in Switzerland directly into an energy yield. However, instead of using the figures above, the efficiency factor they used must have been in the order of 8% to 9% to result in an energy per installed capacity value around 690 Wh/Wp/a. Such low conversion factors are more common with thin film technologies.

A second hypothesis is the employment of an unusually high cell degradation rate. PV cells loose their properties over time, both to the heat they are exposed to, as to the solar radiation itself. While tools such as PVGIS can easily model system losses, they usually leave this degradation rate out. Research centres such as the JRC have assessed PV technologies for decades, concluding on an energy yield degradation rate in the order of 0.5 %/a. Moreover, these long term studies also indicate that cells tend to degrade in a linear fashion.

The following figure presents two hypothetical degradation rates that bring down a PV panel from 1090 Wh/Wp/a to an average yield of 690 Wh/Wp/a over a 25 year lifetime: a liner degradation of 33.5 Wh/Wp/a and a logarithm decline of 4 %/a. In both cases the energy yield dives under half before the end of system life.

While this latter hypothesis is my favourite, it does not explain the employment of the strange energy per unit area figure. Also, these degradation rates would assume that in the face of a fast collapse in energy output owners would never activate panel warranty. 

Final remarks

Replacing the inexplicably low energy yield figures used in this study by those available from the SFOE is already enough to bring the Swiss PV park into positive net energy territory. However, such result is still far from previous PV EROEI assessments, even the highly conservative estimate produced by Prieto & Hall. Just as the energy yield assumptions proved problematic in this study, I expect similar awkwardness to be found on the energy input side of the equation. However, I leave this aspect to be assessed by someone else.

The publication of such a study by a relatively renowned outlet begs for deep reflection. The last article I authored in a scientific journal was over two years in review; this is usually a slow and painstaking process. Being myself an editor and reviewer at scientific publications, I am at a loss to explain how could such a problematic figure of 106 kWh/m2/a have possibly made through the peer review process. It should have immediately raised a red flag to whoever is slightly acquainted with PV technology and economics, calling for close scrutiny by reviewers and editors alike. Something fundamental has failed in the review process at Energy Policy. 

The Take Away

The EROEI figure concluded by Ferroni & Kopkirk for PV is the lowest ever and far below any previous studies.

These authors use awkward units that largely obfuscate their assumptions on yearly energy yield.

A sample of various panel models points to an energy yield under 700 Wh/Wp/a used in this study.

Official statistics point to an average yield well above 900 Wh/Wp/a for the Swiss PV park; this is in line with values from assessment tools like PVGIS.

The peer review process is not functioning properly at Energy Policy.


Ugo Bardi is a member of the Club of Rome and the author of "Extracted: how the quest for mineral resources is plundering the Planet" (Chelsea Green 2014)