Climate Change: Extinction Rebellion and the Language of the Apocalypse (Part 2: A Real Extinction Threat?)

In my previous post, I started to look at the apocalyptic language used by the climate change activist group Extinction Rebellion (XR). I criticised two fact-checking entities, a fact-checking programme hosted by the BBC called More or Less and a fact-checking web site called Climate Feedback, for misrepresenting some of the statements made by one of the founders of XR.

Both of these entities discredited the co-founder of XR, Roger Hallam, through reframing his statements into something very difficult to defend; that is, they misrepresented him as saying that, if we continue on our current CO2 emission trajectory, the planet’s human carrying capacity will  fall from around 7.5 billion today to one billion by the end of the century. In reality, Roger said we “could” see a world with only one billion if we continue with a policy of ‘business as usual’ for fossil fuel.

The death of over six billion is something I would label as an ‘existential’ risk: the risk of a precipitous drop in the planet’s human population leading to the potential collapse of the political, economic and technological structures that come under the broad heading of ‘human civilisation’. So not everyone will die, but a lot will, and the minority that survive will live an impoverished lifestyle that negatively impacts on their well-being.

So what is needed to get us there? In the BBC Radio 4 programme More or Less, one potential trajectory to such a world was given by the presenter Tim Harford:

Extinction Rebellion provided links to articles and speeches by three scientists. None of them mentioned six billion deaths. One of them, a German atmospheric physicist called Hans Schellnhuber, did say that if we have had unlimited global warming, of eight degrees warming, may be the carrying capacity of the earth would go down to just one billion…..

….. But eight degrees of warming is very much a worst case scenario. It’s well above the range discussed in mainstream forecasts of global warming. In the last a hundred and fifty years, we’ve seen one degree of warming.

Before I tackle problems relating to the above statements, I would also like to point out that the programme makers don’t really do justice to Schellnhuber’s credentials. He is the founder of a leading climate research institute in Germany, the Potsdam Institute for Climate Impact Research (PIK), and has been a lead author for the Intergovernmental Panel on Climate Change‘s past assessment reports. He is also the climate change advisor to the European Union Commission,  the German Chancellor Angela Merkel and the Pope. Check out his Wikipedia page here.

Back to the problems. For a start, if the BBC were going to quote Schellnhuber, why didn’t they ring him up and ask his view on the existential risk posed by climate change? And why do they focus on eight degrees as being extremely unlikely, rather than whether existential risk is extremely unlikely? The claim by Roger Hallam was that an existential risk to humanity is perfectly possible. He makes no claims about the degrees of warming the earth may experience.

So what does Schellnhuber think the chances are of saving our civilisation from the negative impact of climate change? From a December 2018 interview.

First, from three minutes onwards:

Q: You just said about we are in a position where we can manage the situation. But on the flip side, what you just said, you are questioning whether civilisation is sustainable. That is a stark difference.

Schellnhuber: If we get it wrong, So if we do the wrong things — policy in economics and psychology, in science — then I think there is a very very big risk that we will just end our civilisation. The human species will survive somehow, but we will destroy almost everything we have built up over the last two thousand years. I’m pretty sure.

Q: What sort of time frame would you put on that kind of …?

Schellnhuber: Oh it can happen pretty soon, pretty quickly because you see, if a minor conflict in Syria is sending so many shock waves through migrants, for example, to Europe. So, it’s all about nonlinearity. It’s all about non-linearity stupid.

Then from nine minutes:

Giving up is not an option. Why? I’ll just give you an example. I don’t know, do you have children? If you would have a child. I have a ten years old boy. Let’s assume he has an accident. And the doctor says “OK we might save his life ,if we do this type of surgery, but there is only a five percent chance, otherwise he will die”.

Will you say, “no we don’t do it, we don’t go ahead with the surgery”? Of course you will do it. And so it’s the situation we have now. I think we have more than a five percent chance of succeeding. But it’s definitely less than 50% in my view.

What’s the option? If we have a final chance to save our culture and our civilisation. I’m just compelled to do it.

So Schellnhuber — a leading climate scientist and advisor to the Pope, Angela Merkel and the EU — thinks we have a less than 50% chance of avoiding an existential crisis brought on by climate change and that such a crisis could come quite quickly.

In conclusion, I don’t know if Tim Harford is being knowingly disingenuous in misrepresenting Roger Hallam’s statements and then misrepresenting the scientist that XR quotes; perhaps, rather, this is just sloppy investigative journalism. But the fact is one of world’s leading climate scientists absolutely supports Roger’s view on climate change risk. Surely that is a thing of interest that the programme should have wanted to explore?

Moreover, if we want to ask questions about existential risk, shouldn’t we approach academics who study existential risk? This is actually not a difficult thing to do since the UK is blessed by a number of university departments that study just such risk. Don’t the More or Less team at the BBC have access to this knowledge?

In my next post, I will look at one of those departments: Cambridge University’s Centre for the Study of Existential Risk (CSER) and some of the research they produce.

In the meantime, I will leave you with a full-length lecture given by Jochim Schellnhuber at Cambridge University in February 2019. It is a masterclass in the communication of current climate change research and I can highly recommend it.

 

 

 

 

 

 

 

 

Climate Change: Extinction Rebellion and the Language of the Apocalypse (Part 1: ‘Will’ versus ‘Could’)

This blog was born of my awakening to the existential threat posed by climate change: in my opinion the “one risk to rule them all”. A 2010 paper by the renowned glaciologist and paleoclimatologist Lonnie Thomson titled “Climate Change: The Evidence and Our Options” was an inspiration. In this paper, he wrote:

Climatologists, like other scientists, tend to be a stolid group. We are not given to theatrical rantings about falling skies. Most of us are far more comfortable in our laboratories or gathering data in the field than we are giving interviews to journalists or speaking before Congressional committees. Why then are climatologists speaking out about the dangers of global warming? The answer is that virtually all of us are now convinced that global warming poses a clear and present danger to civilisation.

It’s been some time since I last posted, and I haven’t done a post on climate for a long while. My last scribbling was part of a series on renewables yet to be finished. Apologies. I was knocked off course in the spring of this year by a young Swedish girl by the name of Greta Thunberg and a ragtag of marvellous misfits who launched a remarkable new movement under the name Extinction Rebellion.

So coming back to post on climate change is coming home. Moreover, there was a reason for avoiding the subject for years: it hurts. Over a period within which I experienced the death of close relatives and divorce, my emotional bandwidth had gone. Climate change is depressing — and best avoided by those who are struggling.

But time has moved on and the bandwidth has been restored. Thus the resolve of Greta Thunberg, and then the force of nature which is Extinction Rebellion, has pushed me back into the fray. I am involved in climate change activism again, and it feels the right thing to do.

Nonetheless, I am also a student of risk and I like to attach numbers to things. The new climate awakening of the last 18 months in Europe has brought with it a whole lexicon of fear: crisis, collapse and catastrophe; emergency and extinction. But what do these things  mean? The philosopher king and queen of Extinction Rebellion, Roger Hallam and Gale Bradbrook, frequently talk in such “end of days” apocalyptic terms.

So the question is whether such predictions are appropriate? And do they reflect science? To tackle this question, I’m going to start by concentrating on the language deployed by Roger Hallam, heard in a string of his YouTube videos (for a recent example see here).

In these videos, Roger starts by explaining the potential for climate-induced doom for the human race and then moves on to state the case for non-violent direct action (NVDA), so forcing government action. His ideas have formed the bedrock philosophy behind Extinction Rebellion (XR), a movement that has come out of nowhere over the last 12 months to become the most successful climate change advocacy group ever.

In April 2019, Roger’s language and learning persuaded thousands of protestors to take to the streets of London and occupy many of its iconic landmarks: Waterloo Bridge,  Oxford Circus,  Marble Arch and Parliament Square. In effect, the UK government ceased to control swathes of the capital for around 10 days.

What was even more stunning was the reaction of the general public. While the XR actions garnered a considerable amount of grumbling and a quite a lot of swearing, they also touched a nerve. The discussion of climate change amongst friends and family has almost become a taboo in the UK, as with almost everywhere else in the world (to see the stats on how often climate change is discussed in the US see here). But the London occupations brought to the surface a growing unease within the population, an unease suggesting something really wasn’t right with the weather, and thus the climate.

In a ComRes opinion poll taken after the April actions, 54% of respondents agreed with the statement “I believe climate change threatens our existence as a species”, a position espoused by XR. Put another way, while the majority of those polled by ComRes didn’t support XR’s actions (26% ‘for’, 32% ‘against’,  43% ‘don’t know’), the consensus now is that climate change is an existential threat.

Almost inevitably, the success of XR has garnered a response from those who don’t want climate change to become an important issue in political debate. The attack has been two-pronged. On the one hand, criticism has been levelled at the so called non-democratic nature of XR in its unwillingness to use traditional poliical channels to effect change. I will leave that issue for another day. On the other hand, a concerted effort has also been made to place XR outside of the scientific climate consensus. Roger and other spokespersons for the movement are portrayed as wild-eyed Cassandras warning about the ‘end of days’. Is such a criticism founded?

To answer that question, let’s start by listening to Roger Hallam in the BBC television programme Hardtalk (if there is a geoblock or time limit preventing your access to this programme, don’t worry as I’ve extracted Roger’s key quotes below):

While the whole programme is worth watching, here is Roger expanding upon catastrophic climate risk. In Roger’s words:

1: “The fact of the matter is, we are facing mass starvation within the next 10 years, social collapse and possible extinction of the human race. It couldn’t be worse.” (from 3:49).

2. “This is the major point Extinction Rebellion is trying to say, is that it is over for this civilisation. The reason it’s over is because of the hard physics. We’re not making a political point or an ideological point or trying to be awkward or all the rest of it. We’re simply saying the science is real, the science is real, it means we’re facing social collapse. The reason we are facing social collapse is because of mass starvation and the reason we are going to have mass starvation is because of the collapse in the weather systems around the world.” (from 6:48)

3. “Teenagers are shitting themselves about what’s happening for the future. They’ve got another 50, 60, 70 years to live on this planet. By that time there could be only one billion people left! I mean that’s six billion people that could have died from starvation of being slaughtered in war. And the scale of it is beyond imagination, isn’t it?” (from 15:23)

4. “I am talking about the slaughter, death, and starvation of six billion people this century. That’s what the science predicts. That’s the trajectory we are on and that requires absolutely desperate measures to stop it. And it’s going to be painful, it’s going to be painful.” (from 16:33)

Now we need to be a bit appreciative here over the fact that written and spoken language differ. We also need to realise that this was a high pressure interview, with I’m sure a lot of adrenalin pumping through Roger’s veins. In short, grammatical phrasing and sentence structure is created in real time with no opportunity for a second edit. So we should be a little careful in attaching profound meaning where none was intended. But with that caveat, let’s look at these four statements.

The first one states that “we are facing mass starvation within the next 10 years”. Let’s see whether the United Nation’s Food and Agriculture Organization (FAO) can collaborate that statement. From the FAO, we know that undernourishment, after many years of decline, is on the rise again.

FAO Undernourishment

Further, within the category of undernourishment, the numbers facing crisis-level food insecurity is also moving upward, with climate change a major contributor. From page 40 of the FAO‘s “The State of Food Security and Nutrition in the World 2018″:

While hunger is on the rise, it is equally alarming that the number of people facing crisis-level good insecurity continues to increase. In 2017, almost 124 million people across 51 countries and territories faced “crisis” levels of acute food security or worse, requiring immediate emergency action to safeguard their lives and preserve their livelihoods. This represents  an increase compared to 2015 and 2016, when 80 and 108 million people, respectively, were reported as facing crisis levels. As with increased levels of hunger, major contributors to crisis-level food insecurity are climate-related, in particular droughts.

So, in effect, Hallam’s “mass starvation” related to climate is already with us. So his statement does appear to reflect scientific fact.

In the second statement, Roger says “it’s over for this civilisation”. This is a little more tricky to interpret. Moreover, there is no time line attached. We could take this to mean over for our existing type of civilisation (for example one built on fossil fuel and/or capitalism) or it is over for civilisation across the planet in any form. The latter interpretation was the line that Sir David Attenborough took in the BBC documentary Climate Change: the Facts (from 2:40).

Standing here in the English countryside, it may not seem obvious but we are facing a manmade disaster on a global scale. In the 20 years since I first started talking about the impact of climate change on our world, conditions have changed far faster than I have ever imagined. It may sound frightening, but the scientific evidence is that if we have not taken dramatic action with the next decade, we could face irreversible damage to the natural world and the collapse of our societies. We’re running out of time, but there is still hope. I believe that if we better understand the threat we face, the more likely it is that we can avoid such a catastrophic future.

Nonetheless, with no number, no date and no definition of the terms civilisation and collapse, it is very difficult to say whether the statement is, in a word beloved of climate change deniers, “alarmist”.

So let’s move on to statement 3. In this statement we have something much more concrete to work with. We have a date, 2090, when present teenagers will be 70 and we have a number, 6 billions deaths taking the carrying capacity of the planet down to one billion. But did he actually say that? No, actually he didn’t! He said “by that time there “could” actually be one billion people left. So this is a statement relating to probability.

Yet in Statement 4, it appears that he is predicting 6 billion dead by 2100. At this point, I believe we need to apply a degree of common sense. Statement 3 starts at 15:23 and Statement 4 starts at 16:33, a mere 70 seconds apart. Has he changed his view on the survival chances of the majority of humankind within just over a minute? Implausible. So how do we reconcile the two statements? Well, for me, it seems pretty obvious. In the final statement, Roger appears to be considering the outcome of “a” trajectory rather than “the” trajectory.

Unfortunately, that is not how the BBC Radio 4 fact-checking programme More or Less decided to deconstruct the interview (here). Nor is it how the climate change fact-checking site Climate Feedback treated Roger’s statement (here), their key takeaway given below:

Climate Feedback
I think, in both instances, the fact checkers have gone down the slippery slope off indulging in straw man arguments; i.e., they are refuting an argument that Roger didn’t actually make. In short, they concentrated on Statement 4, and severed it from Statement 3.

In my next post, I will look in more detail at how the BBC programme More or Less and Climate Feedback came to their conclusions and whether their approach is helpful in assessing climate change risk. Ultimately, I want to move on to the much more interesting question posed by Roger in Statement 3, but with a little tweak. That is, what is the risk of a catastrophic climate outcome by end of century that results in mass death?

Have the Kids Started Caring?

Back in 2011, I wrote a blog post called “Do the Kids Care?” about the attitude of young people toward climate change. The tentative conclusion was they cared less due to their limited experience of risk. Today (15th February 2019) was a day when many of them certainly seemed to care. I had the pleasure of attending a rally in Oxford (part of the #SchoolStrikeforClimate movement), which was inspired by the 16-year old climate activist from Sweden Greta Thunberg.

 
So have global youth undergone a Damascene conversion and suddenly realise the existential threat they face from climate change? Probably not, but I hope that something significant is emerging  here: at least a realisation by youth that they will be expected to clear up the CO2 pollution party from hell thrown by their parents and grandparents.

The jury is out over whether this movement has staying power, but in the meantime the next school student strike is going global and takes place on 15th March; details can be found here:

https://www.facebook.com/events/1994180377345229/

So get out there and give Greta and all the other kids a helping hand!

IMG_0010

And in the meantime, here is my original post from 2011:

Climate change, if nothing else, is a time horizon risk: the longer you live, the more you are exposed to climate change and its impacts. Thus, to follow the logic, the old (and especially childless) should be less sensitive to climate change risk than the young. (For the different question of “Should the kids care?” see ‘Odds of Cooking the Kids’ here, here and here.) But do the young care?

survey last year suggests the young care a little less about climate change than anyone else. This seems rather strange, since the young adults involved would have had a high exposure to the topic from early adolescence both through the media and school.

The first Climate Change Conference took place in Geneva 1979 a few years after a landmark paper by Wally Broecker in 1975 established a link between anthropogenic (human) CO2 emissions and temperature rise. The Intergovernmental Panel on Climate Change (IPCC) was established in 1988, but it probably took another decade before the topic spilled out of the academic community and into the public domain.

By around 2006 or 2007, few people would have remained unaware of the issue, even if they differed about the causes and severity of the problem. The documentary ‘An Inconvenient Truth’ show cased Al Gore’s campaign to educate citizens about the dangers of global warming and received extensive publicity. Meanwhile, the IPCC’s Fourth Assessment Report declared that human-caused factors were ‘very likely’ the cause of climate change and was widely reported. In retrospect, these years appear to have seen the high water mark for public awareness of the risks from climate change (partly because carbon-industry financed lobby groups had only just started to enter the debate on the skeptics’ side).

For a younger generation, the general media buzz over climate change was also supplemented by information they received via their school curricula.

In the UK’s case, a child in high school in the 1980s would only have come across climate change in school if introduced to the topic by an enthusiastic science teacher. In 1995, however, climate change was formally introduced into the National Curriculum, and nowadays a pupil has no choice but to bump up against it in variety of contexts including science, geography and even, occasionally, religious education.

In the United States, the federal, state and local involvement in education have made the delivery of climate change education a little more variable between schools. Nonetheless, there appears to be a consensus among teachers that climate change is taking place and that it should be taught. A position paper (here) from the US National  Association of Geoscience Teachers (NAGT) is unequivocal:

The National Association of Geoscience Teachers (NAGT) recognizes: (1) that Earth’s climate is changing, (2) that present warming trends are largely the result of human activities, and (3) that teaching climate change science is a fundamental and integral part of earth science education.

The National Association of Science Teachers (NSTA) is a little less forthright on the subject, but in a 2007 NSTA President’s report  entitled ‘Teaching About Global Climate Change’ we see this:

Central to environmental literacy is students’ ability to master critical-thinking skills that will prepare them to evaluate issues and make informed decisions regarding stewardship of the planet. The environment also offers a relevant context for the learning and integration of core content knowledge, making it an essential component of a comprehensive science education program.

Two of the most reliable sources of information for classroom teachers are the National Oceanic and Atmospheric Administration and the United Nations Intergovernmental Panel on Climate Change, both offering materials that are scientifically based and bias-free.

No prizes for bravery here, but by endorsing two sources that document the risks related to human-induced climate change, the NSTA in effect is adopting a similar position to the NAGT—but at one remove. The NSTA’s reticence is obviously because science teachers who promote awareness of the problem are likely to receive a lot of push-back; an NSTA survey (here) gives a sense of this:

(Rather disappointingly for a science-based organisation, neither the number of educators who responded nor the climate change beliefs of the responding educators were reported, rendering any firm conclusions problematic).

Overall, however, for those students who had not already taken a firm position vis-a-vis the veracity of human-induced climate change from their parents, the senior school experience over the last 10 years or so would have taught most of them that the climate is changing and anthropogenic carbon emissions are to blame (based on scientific evidence). For those 1990s high school graduates, the school input on the topic would likely have been far more mixed. But by contrast, anyone over 35 is unlikely to have come across climate change at school.

So back to the survey—conducted jointly by the American University, Yale University and George Mason University—titled ‘The Climate Change Generation?’ The generation in question as per the survey definition was a sample of 1001 adults aged between 22 and 35 as of when the survey took place (between December 24, 2009 and January 3, 2010).

Given the educational backdrop of the ‘Climate Change Generation’ we get two immediate counter-intuitive findings from the survey. Younger people neither think about climate change more nor worry about it more (or at least no more than others):

And this being a risk blog, I am particularly interested in people’s perceptions of the personal harm they could incur. Again, the young don’t appear particularly concerned.

Moreover, despite the impression that climate change concern (and activism) is a province of the young (and almost a social norm these days), the data just don’t show this to be true:

Could it be that factor ‘youth’ is not determining the direction of the survey responses  (and when it does, the sign is opposite of what one would expect) because the ‘old young’, who had come of age in the 1990s when climate change was less reported, were diluting the signal in the data? The answer to this is ‘no’ since the survey also split the young adults into two cohorts: in effect, the ‘young young’ and the ‘old young’. Note the answer ‘not at all worried about global warming’ at the bottom of the chart sees the ‘young young’ the least concerned of all:

On reflection, it appears that education has had no impact on the brain’s perception of risk, which takes us into the realm of cognitive psychology. A traditional view of the risk appetite of adolescents has suggested that they have a feeling of invulnerability (and perhaps this extends to those in their twenties as well). However, more modern findings such as a paper by Cohn et al entitled ‘Risk Perception: Differences Between Adolescents and Adults’ suggests this is not the case:

Adolescent involvement in health-threatening activities is frequently attributed to unique feelings of invulnerability and a willingness to take risks. The present findings do not support either proposition and instead suggest that many adolescents do not regard their behavior as extremely risky or unsafe. Compared with their parents, teenagers minimized the harm associated with periodic involvement in health-threatening activities. Ironically, it is periodic involvement in these activi- ties that jeopardizes the health of most adolescents. Thus teenagers may be underestimating the risk associated with the very activities that they are most likely to pursue, such as occasional intoxication, drug use, and reckless driving.

So to get a better idea of what is going on, it is worth moving on to the field of heuristics and biases in the perception or risk, which has become a key area of study in economics and finance over the last 30 years. This new area of investigaton was kicked off by the pioneering work of Nobel Laureates Daniel Kahneman and Amos Tversky; a good and accessible summary of the work can be found in Kahneman’s recent book “Thinking fast and slow“.

One critical finding was the distinction between ‘choice from experience’ and ‘choice from description’. Experimental data show that rare outcomes are overweighted when they are vividly described but are frequently underweighted if they are abstract. By extension, a more abstract threat, like harm from radiation, may be overweighted as a risk as it calls forth rich associations that provide a vivid description: for example, images from Chernobyl, a scene from the movie ‘China Syndrome’ or a picture of a child atom bomb victim suffering from radiation sickness.

Keeping this in mind, climate change risk is rather difficult to grasp in terms of the potential impact on oneself: no photos of dying babies to give us a descriptive representation—or at least only abstract theoretical ones.

Furthermore, risks are underweighted if we have no experience of them. The experience can also go beyond one’s own experience and encompass those of others. Accordingly, a particular teen or adult may not have experienced an auto crash through reckless driving, but it is almost certain that the adult will know someone personally, either family or friend, who has suffered from a reckless driving act. They thus get an experience boost by proxy.

Thankfully, few of us have yet to experience severely negative effects from climate change. However, an elderly person is more likely to have experienced, or known someone who has experienced, a rare event that gives them a proxy association of climate risk. Through having touched on the experience of war, flood  and other natural disasters (and possibly even famine for immigrants from low income countries), older people are better aware that ‘ really bad stuff’ happens.

In all this, sets of statistical tables showing objective probabilities have far less impact on people’s perceptions of risk than one would expect if humans were no more than purely rationale calculating machines. Presenting a person with a dry set of stats will barely move the risk perception needle—whether the subject is vulnerability to HIV infection or the destruction of the planet. We are just not built that way (even if we did do some stats at school).

Critically, though, the old perceive only a little more climate change risk than the young. Humans, as a whole, look like a teenager engaging in unprotected sex when it comes to global warming. Whether this poor risk perception can be changed is something I want to return to in a future post.

Seba’s Solar Revolution Part 5 (A Blended Solution to Intermittency)

In my last post looking at the potential for solar energy, I highlighted the drawbacks identified by Euan Mearns and Roger Andrews in their blog Energy Matters. They emphasise the disjoint between when and where renewable energy can be produced and when and where it is needed. The disconnect between production and consumption makes any consideration of levelized cost of energy (LCOE) problematic.

LCOE is the cost to produce energy at a particular place and time; it is not the cost to deliver energy to the consumer at a particular place and time. Accordingly, while renewables have made great strides to match or even undercut their fossil-fuel rivals in terms of cost competitiveness on an LCOE basis (see the chart below) this isn’t enough to allow renewables to rule the world.

Untitled 2

Critically, renewables suffer from a feast or famine: throughout the day and over the year, you could be producing too much renewable energy that goes well beyond demand or not enough energy to meet demand. Once you crank up renewables on a much larger extent than now, you get into a world of energy deficits and energy surpluses as shown in the Energy Matters chart below (from here):

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Nonetheless, when putting together the chart above, Andrews skips around or simply ignores any counter arguments that could upset his thesis.

Critically, the question of renewable energy intermittency is well-known, but is being tackled by grid operators in a holistic, multi-dimensional manner. There is no silver bullet ready to solve the problem of intermittency; that is, the problem of moving energy through time and space.

Nonetheless, if you are a renewable energy skeptic, you can extract any one solution to the problem of intermittency, deconstruct it and then destroy it. In isolation, this is relatively easy to do, and is a classic straw-man argument. You pick any one solution, crank it up to try to solve the intermittency problem in its entirety, and then rubbish the solution due to the astronomic cost estimate that you produce.

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But the solution to the problem of intermittency comes as a package. A range of solutions to the intermittency problem will be rolled out, and no one solution is expected to tackle the problem of intermittency alone. Restated, if each approach is resolving a bite-sized portion of the problem, it only has to be scaled to a far lower size. The range of such solutions could each have a manageable cost, and after being blended together you get to where you want to go: a renewable energy world. Note, I am not saying this is the likely outcome, I am saying that this is a possible outcome.

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Furthermore, Tony Seba’s predictions are, obviously, forward-looking. So any analysis must be looking at costs out into the future. And those are not just the costs associated with the generation of renewable energy itself, but also the costs to provide a solution to the intermittency problem going out 10 years or more. As of today, if we add the cost of the package of intermittency solutions, 100% energy generation via renewables comes out a lot more expensive than fossil-fuel energy generation  (of course ignoring the cost of climate change). But that says nothing about tomorrow.

What are the partial solutions to the intermittency problem? I would place them into four major categories.

  • Overbuild low cost renewables to partially plug the energy deficits
  • Move renewable energy through space (transmission)
  • Move renewable energy through time (storage)
  • Alter the timing of demand to meet supply

These are the topics for my next posts.

P..S. While checking the link to Energy Matters on this post, I was sad to see that Roger Andrews has just passed away. While I don’t agree with everything he wrote, his posts  have frequently challenged my beliefs and made me delve a lot deeper into the energy literature. Commiserations to his family; he will be missed by the many who follow the Energy Matters blog.

 

The Green New Deal and Modern Monetary Theory (MMT)

This post is a bit of diversion from my recent focus on the mobility and energy revolutions currently taking place (the solar posts are “to be continued”). The Democrats new super star Alexandria Ocasio-Cortez has been making waves since becoming the youngest woman to ever serve in the United States Congress. Yesterday Ocasio-Cortez submitted a non-binding resolution in the House of Representatives under the title “Recognising the duty of the Federal Government to create a Green New Deal“. If you haven’t read the actual document (a couple of pages long), I urge you take a look rather than get a second-hand interpretation. You can find the resolution here. And Ocasio-Cortez introducing the policy here:

The resolution is to be accomplished “through a 10-year national mobilization” to execute a series of projects and achieve a range of goals, one of which is “meeting 100 percent of the power demand in the United States through clean, renewable, and zero-emission energy sources”. Well I think Tony Seba would approve of that even if Tony would believe this will happen regardless of the government’s involvement through the magic of technology and market forces.

Criticisms, or course, have come thick and fast, but one of the most major relates to cost: who will pay for the Green New Deal? The frequently asked question (FAQ) sheet attached to the resolution gives this answer:

How will you pay for it?

The same way we paid for the New Deal, the 2008 bank-bailout and extended quantitative easing programs. The same way we paid for World War II and all our current wars. The Federal Reserve can extend credit to power these projects and investments….

The critical component of this response to the question of payment is the statement that “the Federal Reserve can extend credit to power these projects and investments”. And this is where I am heading with this post. Ocasio-Cortez is not only an advocate of a far-reaching environmental policy aimed at tackling climate change, but she is also an adherent to the rather arcane economic theory of Modern Monetary Theory, or MMT.

MMT focuses on the fact that modern monetary systems are based on fiat money. This means monetary systems where nothing backs the issuance of paper money, unlike under previous systems which were backed by gold or some other real substance. Under such so called ‘fiat money’ systems, the government can never go bankrupt since it has the power to print money. That said, while the government may not be able to bankrupt itself through printing money, it is quite capable of bankrupting the private sector through printing so much money that it sets off hyper-inflation: think Wehrmacht Germany, Zimbabwe or Venezuela. Nonetheless, MMT adherents see a world of difference between using debt and money creation in a responsible way to achieve policy goals and in an irresponsible way to support some form of crony capitalism.

Critically, the general public finds it very hard to understand the fact that the government can create money from nothing, but this is just an irrefutable fact.

Accordingly, the government can impact on the real economy through printing paper money in exchange for labour or goods. Under Ocasio-Cortez’s plan, the US government could print money, via the Federal Reserve, to buy wind and solar farms and pay workers to install them. It would use government debt to get to where it wants to go.

In many aspects, MMT is not far away from traditional Keynesian economics, which encourages governments to smooth out business cycles through engaging in pump priming the economy by running fiscal deficits whenever a recession emerges. Followers of MMT, however, believe that the government’s power over money creation should not just be used as a safety net in times of trouble but also in a much more proactive goal-oriented manner to solve current problems.

Under MMT, you needn’t worry about deficits and debt in and of themselves, but only if they result in the adverse outcomes of rising inflation and real interest rates. According to followers of MMT, if you run a big deficit and build up a lot of debt with neither inflation rising nor real interest rates spiking, then you have nothing to worry about. MMT also shifts the policy balance of power away from central banks to politicians.

At this stage, I recommend you sit down and spend a very fruitful 45 minutes of your time watching the following January 2019 lecture by the most famous advocate for MMT Stephanie Kelton. Kelton is that rare thing in an economics professor: a great communicator. Anyone who has got this far down the blog post will be able to understand the lecture — I promise (honest). More important, by the end of the lecture you will realize that government spending is not like household spending. So next time a politician says that a government must learn to live within its means just like a household, you will understand that the politician in question doesn’t know what he or she is talking about.

And, finally, in response to Prime Minister Theresa May’s claim that “there is no magic money tree”, well, actually there is, and in the UK it sits within the Bank of England (BOE). In a wonderful BBC Radio 4 programme called “Shaking the Magic Money Tree“, Michael Robinson descended into the depths of the BOE to see money created out of nothing: so the money tree does exist!

That said, magic can be a force for good or evil. I’m not saying that Ocasio-Cortez has no constraint over what the government can do deficit-wise in terms of executing a Green New Deal. But the judicious use of government’s deficits to finance ambitious government goals should not be dismissed out of hand. Financing such goals through deficits has been done before, and, handled well, it can be done again.

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Seba’s Solar Revolution Part 4 (A Question of Where and When)

Over the last decade, the efficiency of solar panels has gone up and cost has come down. Accordingly, if we could move solar-generated electricity seamlessly through time and space, even a relatively poorly endowed country like the UK (in terms of solar irradiation and land availability) could meet its energy needs through allocating around 5% of its land mass to solar panels (as I discussed in my last post).

If the world were run by some kind of benevolent green dictator, he or she could possibly just issue a decree mandating a mass solar power build out which would replace all existing fossil fuel plants. In reality, the only dictatorship we face is that of ‘the market’. For solar to spread, therefore, the market must recognise solar as cheaper than existing fossil fuel alternatives.

Moreover, in order to reach a Tony Seba style 100% solar nirvana, solar must transition through a two-stage process. First, it needs to take out all the fossil-fuel competition with respect to new energy generation facilities to be built from now onward. Second, solar must push out all fossil fuel competition in the form of existing energy generation facilities. The first task is much easier than the second.

Energy generation costs are composed of two principal components: 1) the energy generating facility and 2) the ongoing operating and maintenance expenses. The second part is relatively easy to imagine. How much fuel and maintenance is required to produce X amount of energy, say a kilowatt hour (kWh) or megawatt hour (MWh)? For solar, the obvious answer to this question is “not much”. Once you have your panel set up, it just sits there generating electricity when the sun comes up every day. You may occasionally have to clean it and also prevent your local neighbourhood yob writing graffiti all over it or stealing the wires connecting it to the grid, but that’s about all. In economics speak, we describe this situation as one where the marginal cost of generating an additional kWh or MWh of electricity once a panel is in place is close to zero.

The marginal cost when producing 1 kWh or 1 MWh of electricity from a coal or gas-fired facility is, however, not zero since you need to put coal or gas in at one end to get electricity out the other end. For an automobile, you need to stick gasoline in at one end to get motion out the other end (in this case the via engine and the four wheels). Sorry, I know this bit is blindingly obvious.

The more complex bit of the LCOE calculation relates to the capital cost of the energy-generating plant required. For a utility scale solar farm, you will need to secure a large area of land (buy or lease), purchase the requisite number of solar modules, mount them, connect them up and then covert the electricity generated into a grid-compliant standard through the use of inverters and transformers. A 2017 report by the United States National Renewable Energy Laboratory (NREL) shows the cost breakdown of a variety of solar installations by size and also through time in the US.

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Once we know the total cost of the installation, it can then be apportioned over all the electricity generated through the expected lifetime of the facility. Simplistically, the capital cost per unit of energy produced is combined with the operating and maintenance cost of each unit of energy produced to arrive at a single number: the levelled cost of energy (LCOE). The LCOE also takes into account how the project is financed and the time value of money. The NREL provides a more detailed explanation of the LCOE calculation here and also an LCOE calculator that you can play around with here. For those of you who don’t have a financial background and are not familiar with discounted cash flow (DCF) methodology, you can just think of the LCOE as the price at which a project needs to sell its electricity in order to breakeven and stay in business.

Accordingly, if a utility scale solar project has an LCOE of $40 per MWh (which is the same thing as 4 cents per kWh, the financial press switches between the two), then the owners will be very happy bunnies if they can sell their electricity at $50 per MWh. Likewise, an energy consumer may want to enter into a power purchase agreement (PPA) with an energy generator for a set amount of electricity over a set period of time. If a solar utility is offering to enter into the PPA at 4 cents per kWh while a coal-fired facility can only go down to 5 cents per kWh, you will likely go with the solar – other things being equal.

The wording “other things being equal” is critical. Presuming no battery storage is involved, the solar facility can only supply electricity during the day and nothing at night. A factory operating 24/7 needs electricity 24/7. If its weekly requirement is, say, 100 MWh the fact that the solar farm can deliver at $40 per MWh versus $50 for the coal-fired plant will not be a sufficient condition for it to win the contract since it can’t supply the electricity both day AND night. At times, Tony Seba and other commentators can be rather disingenuous in claiming that renewable energy is cheaper than fossil-fuel generated electricity for just this reason. Having an LCOE for renewables lower than that for fossil fuel plants is a necessary but NOT a sufficient condition for renewables to displace fossil fuel. As I stressed in my last post, a kWh or MWh of energy that is not located in time and space is a pretty meaningless concept.

That said, I am not suggesting that we throw LCOE out the window. For renewables to replace fossil fuels, we first need to get the LCOE of renewables below that of fossil fuels and then we need to open up the gap between the two. If solar is generating electricity at $40 per MWh and coal at $100 per MWh, then $60 per MWh is available to transfer the solar generated electricity through time and space. The money could be spent on some form of storage (time) or some form of connection (space). The bigger the gap, the bigger the incentive for markets to try and arbitrage away the cost difference through putting in place mechanisms to transfer energy through such time and space.

With all those caveats in place, it’s time to look at some LCOE numbers. A well-respected benchmark annual appraisal of competing LCOEs is published every November by the investment bank and asset management firm Lazard. The entire slide deck is well worth flipping through and you can find it here, but I will just extract three charts.

First up, you can see that for new build facilities, the LCOE of both wind and utility scale solar is now below that of gas combined cycle and coal. Accordingly, if we didn’t have any issues with respect to the provision of energy in time and space it would be cheaper to deliver all new energy generation through renewables.

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Tony Seba’s claim, however, is that solar will not only be the energy generation vehicle for the future but it will also replace all the old fossil fuel facilities that have been constructed in the past. That is a much tougher hurdle. Remember the LCOE has two principal components: the ongoing operating and maintenance costs and the cost of the facility spread out over all the energy generated over the useful life of that facility.

When looking forward, the cost of building a brand new gas combined cycle or coal facility will be included in the LCOE number, when looking back it won’t. That is because that money has already been spent: it’s a sunk cost. So if solar is to mothball existing fossil fuel power stations, its LCOE must be cheaper that the LCOE of the gas or coal plant made up of the operating and maintenance (O&M) expense alone. The good news from Lazard’s November 2018 report is that wind and solar have got so cheap that they are starting to fulfil that condition as well. The cheapest solar facility at $36 per MWh is cheaper than a large proportion of coal-fired power stations whose operating and O&M costs are between $27 and $45 per MWh.

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Even more encouraging is the fact that solar has been consistently coming down its cost curve just as Tony Seba predicted.

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In addition, in areas of high solar irradiance we have seen 20 year power purchase agreements (PPAs) signed with solar utility scale projects at $20 per MWh or lower. The chart below shows the situation in the US, with new PPA price records being set in states like Arizona and Nevada (source: here). Presumably these PPA prices are higher than the projects underlying LCOE otherwise these projects would be loss-making and the solar utilities wouldn’t sign the agreements.

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Fortunately, the cost declines have been such that even in countries with poorer solar irradiance profiles, like those in northern Europe, solar has become increasingly competitive. The chart below is taken from a report by the German Fraunhofer Institute for Solar Energy Systems (ISE). At the time of this post, one US dollar bought 0.87 euros. Keeping that exchange rate in mind, ISE forecasts that the cheapest utility scale solar installations will see their LCOE drop from 4 euros per MWh to 2 euros around 2032. At that price solar will be far cheaper than coal and combined-cycle gas turbine plants.

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The upshot of this analysis is that countries that are well endowed in terms of solar irradiance already have solar plants that are cheaper than their fossil fuel competition on an LCOE basis, and countries that are less well endowed will see their solar plants winning out over the fossil fuel competitors on an LCOE basis over the next 10 years or so as solar costs continue to decline.

And now for some push back from the renewable energy skeptics Euan Mearns and Roger Andrews from the blog Energy Matters. In November 2018, Spain announced that it intended to move to 100% renewable generated electricity by 2050. Compared with Tony Seba’s claim of 100% solar by 2030 across the entire energy spectrum, it doesn’t seem so aggressive, but let’s put that to one side. In a post in November, Energy Matters took umbrage over the Spanish government’s claim and proceeded to show why such a target would be impossible to achieve.

At the heart of Energy Matters Roger Andrews’ argument is the claim that if we adopted renewables entirely to drive the electricity grid, it would become impossible to transport sufficient energy through time. Solar and wind’s intermittency would lead to large gaps in energy generation, and these gaps would be impossible to fill economically through the use of storage or by any other means. For his analysis, Andrews picked out the average electrical energy consumption and production patterns for two months in Spain: January and July. I will just concentrate on July here, but recommend you read the entire post to follow his argument from beginning to end. Here is the current contribution of renewables production to electricity consumption in July in Spain:

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And after scaling up renewables production:

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At this point, it’s worth reproducing the commentary accompanying this chart:

Obviously Spain plans to fill the hole with wind and solar. This approach has one thing going for it – the peaks and troughs in renewables generation are a good match to the demand peaks and troughs. But when we scale up July 2018 wind and solar generation (by a factor of 4.5) to match July 2018 demand we see that the amplitudes don’t cooperate.

Andrews then goes on  to produce a chart showing the deficits and surpluses:

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Which could only be equated by putting into place 1 terawatt-hours (1 TWh) of storage in his view:

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In January, the mismatch is even worse with a requirement for 2 TWh of storage to solve the intermittency problem. Roger Andrews further speculated that potentially 5 TWh to 10 TWh may be required to achieve energy security across the entire year. As an aside, how much would a TWh of storage cost? If we are going to provide such storage via batteries, the RNEL in a recent reported issued in January 2019 estimates the cost of a 4-hour system at $380 per kWh.

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Unfortunately, a terawatt-hour is a billion times bigger than a kilowatt hour. So to provide 1 TWh of battery storage would cost $380 billion at current prices. So to get the amount of storage Andrews suggests, we need trillions of dollars. Given Spain’s gross domestic product was only about $1.3 trillion in 2019, buying trillions of dollars worth of batteries looks unrealistic. Of course, there are other storage options like pumped storage, which Andrews briefly considers, but these have major environmental impacts.

So has Roger Andrews thrust a dagger into Tony Seba’s dream of golden world of solar? Well, these Energy Matters posts are certainly thought-provoking, but if I had a criticism it would be that they suffer from an awful lot of confirmation bias. Andrews appears intent on skewering renewables at the outset and then builds his argument to achieve that end. Accordingly, he frequently makes assumptions in his calculations that look somewhat dubious. In my next post, I will subject Roger Andrews’ skepticism to bit of my own skepticism to see if we can resurrect Tony Seba’s dream .

 

Seba’s Solar Revolution Part 3 (Where to Put the Panels)

In my last post, I mentioned that the late Cambridge University professor David Mackay was skeptical over the ability of solar to play a lead role in decarbonising the world’s energy infrastructure. MacKay’s highly influential book “Sustainable Energy Without the Hot Air” is rooted in basic science. Yet, despite the text being peppered with scientific identities, it also includes a number of value judgements that touch on the world of economics. And it is from these value judgements that MacKay’s skepticism arises.

MacKay’s book is principally concerned with what it would take to decarbonise the UK economy. Tony Seba, in contrast, forecasts that solar can power the globe not just the UK. In this post, I will stay with the UK, although I will look at other countries in future posts. Nonetheless, for Tony to be right, each and every country must be able to secure its energy needs through solar including the UK (though the solar energy may be imported from abroad). Accordingly, if Mackay’s argument is right (that is that the UK’s solar resource in inadequate) then Tony’s is wrong (notwithstanding the import argument).

Two of the major pushbacks against solar rest on the land mass requirement for sufficient energy generation and the intermittent nature of solar that puts unbearable stresses on the grid. As a former economist by training, I regard such arguments as second-order ones. They are both really subsumed under cost issues. Land is just a scarce resource like any other, and if the return on the land used for solar is higher than that for any other use, then it should be allocated to solar-power usage (that calculation can take into account the cost of climate change and the public good value of land).

Moreover, the unit of energy we are working with in this post, a kilowatt hour, is quite simplistic in economic terms. Energy is demanded at a particular place and at a particular time (hour of the day, and day of the year). A kilowatt hour generated in mid-summer in Spain in July, it not the same thing as a kilowatt hour consumed in mid-winter in London in January. The levelised cost approach (I will have a lot to say on that in future), which is used to compare different energy-producing assets, doesn’t take time and place into account.

In reality, we can think of the energy market as composed of 8,760 hour-long blocks (24 hours times 365 days) with a GPS attached to each one. In each of these GPS-stamped timed blocks, the market will equalise supply and demand at a certain price.

MacKay’s analysis only implicitly addresses the economics. Nonetheless, before we start moving energy through time and space, we must ensure that we have enough energy to move in the first place. MacKay does tackle that question.

In a section of his book titled “Fantasy time: solar farming”, Mackay conducts a thought experiment within which he covers 5% of the UK land with 10%-efficient solar photovoltaic panels.

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He starts by calculating that “the average raw power of sunshine per square metre of flat ground (in the UK) is roughly 100 W/m2″. However, with a 10% efficiency photovoltaic panel, of the 100 W/m2 only 10 W/m2 is converted into electricity. From my last post we also know that if we leave a 40W light bulb on all day, it will use up nearly 1 kWh of power (0.04kW times 24). So if we generate 10 W per a one metre squared solar panel, we will get a quarter of that in energy, or 0.25 kWh. MacKay in his calculation has allocated 5% of the UK’s land mass to be used for solar power, which gives 200 m2 to each UK citizen. Times 200 by 0.25 kWh and we get 50 kWh per person per day, which compares with total energy demand of 125 kWh per person per day.

Also, as an aside, note that his calculation goes from power (solar irradiance measured in watts or kilowatts) into an energy number (solar insolation measured in watt hours or kilowatt hours).

At this point, let’s take a step back and look at that allocation of 5% of the UK’s land mass to solar panels. The UK land area is 25.25 million hectares and the population 66 million. Divide one by the other and we get around 0.38 hectares per person, (or just under an acre), which is the same thing as 3,800 m2. MacKay gives each person in the UK 4,000 m2 of land each since the population of the UK was about 5 million smaller when he was working out the maths. However, these numbers are near enough.

Switching from metres squared per person to number of persons per square kilometre, which is the standard measure when comparing countries, I have put together a table of population densities for selected countries, mostly ones with large populations, below. Note that a hectare (10,000 m) is 0.01 of a square kilometre, so 0.4 hectares (40,000 mor 0.004 square kilometres) per person translates into 250 people per square kilometre.

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From the table we can see that only the Netherlands, Japan, the Philippines, India and Bangladesh have population densities higher than the UK. So if the UK can become energy self-sufficient via solar it bodes very well for the rest of the world (putting differing solar irradiance numbers for each country aside for the time being). Moreover, the really profligate energy users, like the USA and Australia (which get through over twice the energy per person than the UK), have the advantage of having a lot of land.

Back to the UK and MacKay’s fantasy time solar farming:

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That 50 kWh per day per person amounts to 40% of the UK’s energy consumption of 125 kWh per person per day. Accordingly, if we hold our 10% panel efficiency steady, then to meet 100% of UK energy requirements we would need to cover 12.5% of the UK land mass with solar panels (about 500 m2 per person).

Critically, MacKay headed his calculation “fantasy time” since he felt the calculation rested upon an unrealistically high cost. Fortunately, this is one area where MacKay was wrong (and Seba right): those fantasy cost reductions have come true (from Bloomberg‘s New Energy Finance (BNEF)‘s New Energy Outlook 2018):

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In short, MacKay was far too pessimistic when it came to the cost curve. BNEF calculates a learning rate of 28.5% for solar PV. The learning rate 28.5% means that every time production capacity for solar PV panels is doubled, the cost of those panels comes down by 28.5%. This is an example of a virtuous circle: lower costs spur greater demand for the panels, which spurs greater production, which spurs future cost cuts and thus greater demand — and so the cycle goes on. (Of course, the panels are not the only components that go into a utility sized solar farm and all the other components will have their own learning curves and, hopefully, declining cost curves. We will come back to that in a later post.)

We are 10 years on from when MacKay wrote Without the Hot Air and already solar is overtaking all existing sources of fossil-fueled energy production in terms of cost competitiveness. Of course, there is a big caveat here: production costs are very different from the cost to deliver energy to a customer at a particular time and at a particular place as I have flagged above. Nonetheless, MacKay was worried about how solar stacked up cost-wise on a production basis out to 2050. That worry was misplaced.

How audacious is this plan? The solar power capacity required to deliver this 50 kWh per day per person in the UK is more than 100 times all the photovoltaics in the whole world. So should I include the PV farm in my sustainable production stack? I’m in two minds. At the start of this book I said I wanted to explore what the laws of physics say about the limits of sustainable energy, assuming money is no object. On those grounds, I should certainly go ahead, industrialize the countryside, and push the PV farm onto the stack. At the same time, I want to help people figure out what we should be doing between now and 2050. And today, electricity from solar farms would be four times as expensive as the market rate. So I feel a bit irresponsible as I include this estimate in the sustainable production stack in figure 6.9 – paving 5% of the UK with solar panels seems beyond the bounds of plausibility in so many ways.

A second observation (or criticism) is that MacKay seems to have also been too pessimistic in term of not just his cost assumption but also efficiency. In the above calculation, MacKay used 10% efficiency panels:

I assumed only 10%-efficient panels, by the way, because I imagine that solar panels would be mass-produced on such a scale only if they were very cheap, and it’s the lower-efficiency panels that will get cheap first.

In reality, those crystalline-silicon PV modules shown in the BNEF report above are far more efficient. From the United States Department of Energy:

Crystalline silicon PV cells are the most common solar cells used in commercially available solar panels…..

……Crystalline silicon PV cells have laboratory energy conversion efficiencies over 25% for single-crystal cells and over 20% for multicrystalline cells. However, industrially produced solar modules currently achieve efficiencies ranging from 18%–22% under standard test conditions.

 

True, these efficiencies are at the panel level not at the solar farm level. A utility scale solar facility will also need room for inverters, control panels, transmissions mechanisms, maintenance huts, security facilities and so on. Yet, we are already at around 20% efficiency levels for commercial products in 2019. Even if we knock off a few percentage points of efficiency to take account of ground cover occupied by stuff needed for a solar installation other than the panels, we are still far above MacKay’s efficiency figure.

A second area where MacKay was far too pessimistic with respect to the technology relates to the Shockley-Queisser limit. This limit sets the maximum theoretical upper efficiency limit of a single layer solar cell to around 33%. However, a new generation of multijunction cells has hopped over the Shockley-Queisser limit. With a two-layer cell your theoretical ceiling is 44% and with three layers 50%. The US National Renewable Energy Laboratory (NREL) shows the major improvements achieved in the past and those predicted for the future. The energy academic Varun Sivaram also devotes a chapter in his book “Taming the Sun” to these frontier PV technologies.

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Currently, the really super-high efficiency panels that are up at 40% are not cost competitive enough to adopt for commercial use. Further, most have drawbacks in terms of manufacturing cells at sufficient size and also with respect to building cells durable enough to be deployed in real-world field conditions. Yet results to date suggest the more efficient panels have kept migrating out of the laboratory and into the marketplace at an ever-falling price.

Given where we are now in terms of panel efficiency and where we will likely be in 10 years time, it is possible that the 200 m2 of land allocated by MacKay to every UK citizen for solar panels could actually meet all the UK energy needs; that is, 125 kWh per person per day if we were deploying 25% efficiency panels (provided that the energy could be transferred though time and space). Further, once solar PV technology can be incorporated into roof tiles and road pavings, not all of the required space need be taken from agriculture land (figure below taken from Without the Hot Air“).

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Then, of course, we could add energy generated from wind into our mix. Each additional kWh coming from wind energy means one less kWh needs to come from solar energy. Tony Seba’s focus was on solar, but I see solar and wind as inseparable twins.

Overall, Mackay was far too pessimistic over the ability of solar to come down its cost curve. In my next post, however, I want to look at an even more potent argument against the future primacy of solar. The blogger Euan Mearns and his co-contributor Roger Andrews are not huge fans of renewables and feel the displacement of solar is a pipe dream of green fantasists. We shall see what they have to say.