Energy And Civilization: a review

Also published at and BiophysEco.

If you were to find yourself huddled with a small group of people in a post-crash, post-internet world, hoping to recreate some of the comforts of civilization, you’d do well to have saved a printed copy of Vaclav Smil’s Energy and Civilization: A History.

Smil’s new 550-page magnum opus would help you understand why for most applications a draft horse is a more efficient engine than an ox – but only if you utilize an effective harness, which is well illustrated. He could help you decide whether building a canal or a hard-topped road would be a more productive use of your energies. When you were ready to build capstans or block-and-tackle mechanisms for accomplishing heavy tasks, his discussion and his illustrations would be invaluable.

But hold those thoughts of apocalypse for a moment. Smil’s book is not written as a doomer’s handbook, but as a thorough guide to the role of energy conversions in human history to date. Based on his 1994 book Energy in World History, the new book is about 60% longer and includes 40% more illustrations.

Though the initial chapters on prehistory are understandably brief, Smil lays the groundwork with his discussion of the dependency of all living organisms on their ability to acquire enough energy in usable forms.

The earliest humanoids had some distinct advantages and liabilities in this regard. Unlike other primates, humans evolved to walk on two feet all the time, not just occasionally. Ungainly though this “sequence of arrested falls” may be, “human walking costs about 75% less energy than both quadrupedal and bipedal walking in chimpanzees.” (Energy and Civilization, pg 22)

What to do with all that saved energy? Just think:

The human brain claims 20–25% of resting metabolic energy, compared to 8–10% in other primates and just 3–5% in other mammals.” (Energy and Civilization, pg 23)

In his discussion of the earliest agricultures, a recurring theme is brought forward: energy availability is always a limiting factor, but other social factors also come into play throughout history. In one sense, Smil explains, the move from foraging to farming was a step backwards:

Net energy returns of early farming were often inferior to those of earlier or concurrent foraging activities. Compared to foraging, early farming usually required higher human energy inputs – but it could support higher population densities and provide a more reliable food supply.” (Energy and Civilization, pg 42)

The higher population densities allowed a significant number of people to work at tasks not immediately connected to securing daily energy requirements. The result, over many millennia, was the development of new materials, tools and processes.

Smil gives succinct explanations of why the smelting of brass and bronze was less energy-intensive than production of pure copper. Likewise he illustrates why the iron age, with its much higher energy requirements, resulted in widespread deforestation, and iron production was necessarily very limited until humans learned to exploit coal deposits in the most recent centuries.

Cooking snails in a pot over an open fire. In Energy and Civilization, Smil covers topics as diverse as the importance of learning to use fire to supply the energy-rich foods humans need; the gradual deployment of better sails which allowed mariners to sail closer to the wind; and the huge boost in information consumption that occurred a century ago due to a sudden drop in the energy cost of printing. This file comes from Wellcome Images, a website operated by Wellcome Trust, a global charitable foundation based in the United Kingdom, via Wikimedia Commons.

Energy explosion

The past two hundred years of fossil-fuel-powered civilization takes up the biggest chunk of the book. But the effective use of fossil fuels had to be preceded by many centuries of development in metallurgy, chemistry, understanding of electromagnetism, and a wide array of associated technologies.

While making clear how drastically human civilizations have changed in the last several generations, Smil also takes care to point out that even the most recent energy transitions didn’t take place all at once.

While the railways were taking over long-distance shipments and travel, the horse-drawn transport of goods and people dominated in all rapidly growing cities of Europe and North America.” (Energy and Civilization, pg 185)

Likewise the switches from wood to coal or from coal to oil happened only with long overlaps:

The two common impressions – that the twentieth century was dominated by oil, much as the nineteenth century was dominated by coal – are both wrong: wood was the most important fuel before 1900 and, taken as a whole, the twentieth century was still dominated by coal. My best calculations show coal about 15% ahead of crude oil …” (Energy and Civilization, pg 275)

Smil draws an important lesson for the future from his careful examination of the past:

Every transition to a new form of energy supply has to be powered by the intensive deployment of existing energies and prime movers: the transition from wood to coal had to be energized by human muscles, coal combustion powered the development of oil, and … today’s solar photovoltaic cells and wind turbines are embodiments of fossil energies required to smelt the requisite metals, synthesize the needed plastics, and process other materials requiring high energy inputs.” (Energy and Civilization, pg 230)

A missing chapter

Energy and Civilization is a very ambitious book, covering a wide spread of history and science with clarity. But a significant omission is any discussion of the role of slavery or colonialism in the rise of western Europe.

Smil does note the extensive exploitation of slave energy in ancient construction works, and slave energy in rowing the war ships of the democratic cities in ancient Greece. He carefully calculates the power output needed for these projects, whether supplied by slaves, peasants, or animals.

In his look at recent European economies, Smil also notes the extensive use of physical and child labour that occurred simultaneously with the growth of fossil-fueled industry. For example, he describes the brutal work conditions endured by women and girls who carried coal up long ladders from Scottish coal mines, in the period before effective machinery was developed for this purpose.

But what of the 20 million or more slaves taken from Africa to work in the European colonies of the “New World”? Did the collected energies of all these unwilling participants play no notable role in the progress of European economies?

Likewise, vast quantities of resources in the Americas, including oil-rich marine mammals and old-growth forests, were exploited by the colonies for the benefit of European nations which had run short of these important energy commodities. Did this sudden influx of energy wealth play a role in European supremacy over the past few centuries? Attention to such questions would have made Energy and Civilization a more complete look at our history.

An uncertain future

Smil closes the book with a well-composed rumination on our current predicaments and the energy constraints on our future.

While the timing of transition is uncertain, Smil leaves little doubt that a shift away from fossil fuels is necessary, inevitable, and very difficult. Necessary, because fossil fuel consumption is rapidly destabilizing our climate. Inevitable, because fossil fuel reserves are being depleted and will not regenerate in any relevant timeframe. Difficult, both because our industrial economies are based on a steady growth in consumption, and because much of the global population still doesn’t have access to a sufficient quantity of energy to provide even the basic necessities for a healthy life.

The change, then, should be led by those who are now consuming quantities of energy far beyond the level where this consumption furthers human development.

Average per capita energy consumption and the human development index in 2010. Smil, Energy and Civilization, pg 363


Smil notes that energy consumption rises in correlation with the Human Development Index up to a point. But increases in energy use beyond, roughly the level of present-day Turkey or Italy, provide no significant boost in Human Development. Some of the ways we consume a lot of energy, he argues, are pointless, wasteful and ineffective.

In affluent countries, he concludes,

Growing energy use cannot be equated with effective adaptations and we should be able to stop and even to reverse that trend …. Indeed, high energy use by itself does not guarantee anything except greater environmental burdens.

Opportunities for a grand transition to less energy-intensive society can be found primarily among the world’s preeminent abusers of energy and materials in Western Europe, North America, and Japan. Many of these savings could be surprisingly easy to realize.” (Energy and Civilization, pg 439)

Smil’s book would indeed be a helpful post-crash guide – but it would be much better if we heed the lessons, and save the valuable aspects of civilization, before apocalypse overtakes us.


Top photo: Common factory produced brass olive oil lamp from Italy, c. late 19th century, adapted from photo on Wikimedia Commons.

The Carbon Code – imperfect answers to impossible questions

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“How can we reconcile our desire to save the planet from the worst effects of climate change with our dependence on the systems that cause it? How can we demand that industry and governments reduce their pollution, when ultimately we are the ones buying the polluting products and contributing to the emissions that harm our shared biosphere?”

These thorny questions are at the heart of Brett Favaro’s new book The Carbon Code (Johns Hopkins University Press, 2017). While he  readily concedes there can be no perfect answers, his book provides a helpful framework for working towards the immediate, ongoing carbon emission reductions that most of us already know are necessary.

Favaro’s proposals may sound modest, but his carbon code could play an important role if it is widely adopted by individuals, by civil organizations – churches, labour unions, universities – and by governments.

As a marine biologist at Newfoundland’s Memorial University, Favaro is keenly aware of the urgency of the problem. “Conservation is a frankly devastating field to be in,” he writes. “Much of what we do deals in quantifying how many species are declining or going extinct  ….”

He recognizes that it is too late to prevent climate catastrophe, but that doesn’t lessen the impetus to action:

There’s no getting around the prospect of droughts and resource wars, and the creation of climate refugees is certain. But there’s a big difference between a world afflicted by 2-degree warming and one warmed by 3, 4, or even more degrees.”

In other words, we can act now to prevent climate chaos going from worse to worst.

The code of conduct that Favaro presents is designed to help us be conscious of the carbon impacts of our own lives, and work steadily toward the goal of a nearly-complete cessation of carbon emissions.

The carbon code of conduct consists of four “R” principles that must be applied to one’s carbon usage:

1. Reduce your use of carbon as much as possible.

2. Replace carbon-intensive activities with those that use less carbon to achieve the same outcome.

3. Refine the activity to get the most benefit for each unit of carbon emitted.

4. Finally, Rehabilitate the atmosphere by offsetting carbon usage.”

There’s a good bit of wiggle room in each of those four ’R’s, and Favaro presents that flexibility not as a bug but as a feature. “Codes of conduct are not the same thing as laws – laws are dichotomous, and you are either following them or you’re not,” he says. “Codes of conduct are interpretable and general and are designed to shape expectations.”

Street level

The bulk of the book is given to discussion of how we can apply the carbon code to home energy use, day-to-day transportation, a lower-carbon diet, and long distance travel.

There is a heavy emphasis on a transition to electric cars – an emphasis that I’d say is one of the book’s weaker points. For one thing, Favaro overstates the energy efficiency of electric vehicles.

EVs are far more efficient. Whereas only around 20% of the potential energy stored in a liter of gasoline actually goes to making an ICE [Internal Combustion Engine] car move, EVs convert about 60% of their stored energy into motion ….”

In a narrow sense this is true, but it ignores the conversion costs in common methods of producing the electricity that charges the batteries. A typical fossil-fueled generating plant operates in the range of 35% energy efficiency. So the actual efficiency of an electric vehicle is likely to be closer to 35% X 60%, or 21% – in other words, not significantly better than the internal combustion engine.

By the same token, if a large proportion of new renewable energy capacity over the next 15 years must be devoted to charging electric cars, it will be extremely challenging to simultaneously switch home heating, lighting and cooling processes away from fossil fuel reliance.

Yet if the principles of Favaro’s carbon code were followed, we would not only stop building internal combustion cars, we would also make the new electric cars smaller and lighter, provide strong incentives to reduce the number of miles they travel (especially miles with only one passenger), and rapidly improve bicycling networks and public transit facilities to get people out of cars for most of their ordinary transportation. To his credit, Favaro recognizes the importance of all these steps.

Flight paths

As a researcher invited to many international conferences, and a person who lives in Newfoundland but whose family is based in far-away British Columbia, Favaro has given a lot of thought to the conundrum of air travel. He notes that most of the readers of his book will be members of a particular global elite: the small percentage of the world’s population who board a plane more than a few times in their lives.

We members of that elite group have a disproportionate carbon footprint, and therefore we bear particular responsibility for carbon emission reductions.

The Air Transport Action Group, a UK-based industry association, estimated that the airline industry accounts for about 2% of global CO2 emissions. That may sound small, but given the tiny percentage of the world population that flies regularly, it represents a massive outlier in terms of carbon-intensive behaviors. In the United States, air travel is responsible for about 8% of the country’s emissions ….”

Favaro is keenly aware that if the Carbon Code were read as “never get on an airplane again for the rest of your life”, hardly anyone would adopt the code (and those few who did would be ostracized from professional activities and in many cases cut off from family). Yet the four principles of the Carbon Code can be very helpful in deciding when, where and how often to use the most carbon-intensive means of transportation.

Remember that ultimately all of humanity needs to mostly stop using fossil fuels to achieve climate stability. Therefore, just like with your personal travel, your default assumption should be that no flights are necessary, and then from there you make the case for each flight you take.”

The Carbon Code is a wise, carefully optimistic book. Let’s hope it is widely read and that individuals and organizations take the Carbon Code to heart.


Top photo: temporary parking garage in vacant lot in Manhattan, July 2013.

More than one way to fall off a cliff

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Wonkometer Warning MH-225The “energy cliff” is a central concept in ecological economics, and it’s based on a very simple ratio. But for me this principle was a slippery thing to grasp, and I eventually realized some of the most common graphs used to illustrate the Energy Cliff were leaving me with a misleading mental image.

This column takes a closer look at Energy Return on Energy Invested (ERoEI, EROEI or simply EROI) and the Energy Cliff, concluding with the question of how and whether the Energy Cliff might be experienced as a historical phenomenon.

The Energy Cliff as a mathematical function

Below are two frequently used versions of the Energy Cliff graph, based on the pioneering work of Charles Hall. They illustrate the relationship between Energy Return on Energy Invested and the percentage of energy production that is “surplus”, i.e., not needed by the energy sector for its own work and therefore available for use by the rest of society.

Chart accessed via

Chart accessed via

Chart from Tim Morgan, Life After Growth, Kindle edition, locus 980

Chart from Tim Morgan, Life After Growth, Kindle edition, locus 980

In each case the EROEI is shown on the horizontal axis with lowest values at the right. The apparent suddenness of the drop-off in surplus energy depends on the relative scales of the axes and maximum value shown for EROEI, but in each case the drop-off becomes nearly perpendicular as EROEI falls below 10 – thus the name “Energy Cliff”.

Simple enough, eh? But after seeing this graph presented in several books and essays, I still found the concept hard to master. I kept asking myself, “How does that work again?” or “Why does energy supply drop off so suddenly?”

The problem, I realized, is that the impression these graphics leave in my mind is at odds with the intent. As these examples show, the “Energy for society” or “Profit energy” dominates the graphic visually, and the “Energy used to procure energy” or “Cost energy” seems like such a small sliver that it couldn’t possibly be that important. Mathematically naïve as that impression may have been, it nevertheless made it difficult for me to retain a clear understanding of the Energy Cliff.

The solution for me was to play with the graph until I felt I understood it clearly, using imagery that reinforced the understanding.

It was most helpful, I found, to present the graph not as an unbroken continuum between the two variables, but as a bar chart showing discrete values of Energy Return on Energy Invested: 1, 2, 3, 4, etc up to 50.

The Energy Cliff as a Bart Chart

Visualizing the numbers this way minimizes the tendency to see the surplus energy, or Net energy output, as one massive block. Just as importantly, it allowed me to easily focus on the relationship between specific values of Energy input and Net energy output.

For example, at the far right end of the graph is the ERoEI value 1. This corresponds to a bare break-even scenario. An oil well with this ERoEI would not be worth drilling: we would use up one barrel of oil to drill and operate the well, and it would spit out exactly one barrel in return, leaving us with no surplus energy for our efforts.

An ERoEI of 2 corresponds to a Net energy output of 50%. To return to our Proverbial Oil Corp., we burn one barrel of oil to drill and operate a well, and the well spits out two barrels, leaving us with a net gain of 1 barrel or 50% of the Total energy output.

Our oil wells with ERoEI of 3 give us 3 barrels total for every one we invest, for a net energy gain of 2 barrels or 66.6%, wells with ERoEI of 4 give us a net energy output equal to 75% of their total energy output, wells with ERoEI of 5 give us a net energy output equal to 80% of their total energy output, and so on.

We can also see clearly that the Energy input and Net energy output percentages change very slowly for ERoEI values above 20 – at which point Energy input is 5% and Net energy output is 95% of Total energy output).

There is another simple tweak to this chart that can vividly illustrate the sudden drop-off: animation. (And since most of us use supercomputers capable of guiding a moon mission for our morning reading, why not throw in some animation?)

The animated Energy Cliff – click chart to set in motion

The animated Energy Cliff – click chart to set in motion

By focusing attention on just a narrow range of ERoEI values at a time, this moving bar graph illustrates the fact that Net energy output changes slowly throughout most of the range, and then drops off suddenly and swiftly.

The animated graph relies on the element of time as a key facet of the presentation. That begs the question: can the Energy Cliff chart be read as a function of time?

The Energy Cliff as a historical phenomenon

It is easy to look at the Energy Cliff graphic as a chronological progression, given the convention of viewing timelines with past on the left and future on the right. That would be a mistake – there is no element of time in the chart – but it might be a useful mistake if made consciously.

It’s true that ERoEI rates have been declining slowly for the past 50 years, and many new energy technologies today have ERoEI rates of 10 or lower. And in fact, the Energy Cliff chart is sometimes presented as evidence that an impending energy crisis is mathematically inevitable. While that would be an unwarranted extrapolation from a graph of a simple exponential curve, it isn’t hard to cherry-pick data that graphs to a shape similar to the Energy Cliff.

Consider the following table of ERoEI rates over time.

Selected ERoEI rates over time

This table starts with EROEI rates before the industrial age, and finishes with rates that could plausibly represent the collapse of industrial society. When graphed these numbers show a drop-off much like the Energy Cliff, with the addition of a steep slope going up at the outset of industrial civilization. The values are roughly scaled chronologically, to represent the length of time during which very high EROEI prevailed – basically, the 20th century.

Net Energy over time - chart 1 copy


The numbers cherry-picked for this chart include, crucially, an EROEI for photovoltaic panels in Spain as calculated by Charles Hall and Pedro Prieto, which was the subject of spirited discussion recently on Resilience. At 2.45, this EROEI is far below the level needed to support a highly complex economy. If this number is correct and turns out to be representative of photovoltaics more generally, then the scenario suggested in the above chart is plausible. As high EROEI petroleum sources are depleted, we turn to bottom-of-the-barrel resources like tar sands, and then to solar panels which are even less energy-efficient. Complex industrial society soon collapses, and the vast majority of us must return to the fields.

For a very different picture, we could use the EROEI for solar panel installations presented by Ugo Bardi in Resilience, from a study by Bhandari et al. In this view, photovoltaics in Spain have an EROEI of 11–12, safely out of the drop-off zone of the Energy Cliff. In this scenario we’d have no need for last-ditch fossil fuels from tar sands, solar panels would produce enough surplus energy to create more solar panels and keep industrial society rolling cleanly along, and the Energy Cliff would be a mathematical function but not a historical reality.

Net Energy over time - chart 1 copy


These two charts are equally over-simplified, ignoring other renewable resource energy technologies with widely varying EROEI rates such as hydro-electric generation. It’s unknown how long we might stretch out the dwindling supply of high-EROEI fossil fuels, or whether there will be a collective decision to clamp down on carbon emissions and leave fossil fuels in the ground. And I’m unqualified to make any judgment on whether the Hall/Prieto or the Bhandari assessment of photovoltaics is most realistic.

In presenting these two different charts I merely want to illustrate that while the Energy Cliff graph of a mathematical function is simple and direct, extrapolating from this simple function to forecast historical trends is fraught with uncertainty.

Top graphic: “The Fool” in the Rider-Waite Tarot deck dances gayly at the edge of a precipice.


Naomi Klein, photograph by Joe Mabel, distributed via Wikimedia Commons

A renewable energy economy will create more jobs. Is that a good thing?

Also published at

In a tidal wave of good news stories, infographics and Facebook memes about renewable energy job creation, the implicit, unquestioned assumption is that More Jobs = A Healthier Economy.

A popular Facebook meme, based on the Stanford University Solutions Project, celebrates the claim that in a renewable energy-powered Canada, 40% more people will work in the energy sector.

From the Environment Hamilton Facebook page.

From the Environment Hamilton Facebook page.


In elaborate info-graphics, the Solutions Project provides comparable claims for all 50 US states and countries around the world – although “assertion-graphic” might be a better term, since the graphics are presented with no footnotes and no clear links to any data that might allow a skeptical mind to evaluate the conclusions.

From The Solutions Project website.

From The Solutions Project website.

And Naomi Klein, author of This Changes Everything and one of the proponents of The Leap Manifesto, cites the Energy Transition in Germany and notes that 400,000 new jobs have already been created. In her hour-long talk on the CBC Radio Ideas program and podcast, Klein gets at some of the key issues that will determine whether More Energy Jobs = A Good Thing, and we’ll return to this podcast later.

To start, though, let’s look at the issue through the following proposition:

The 20th century fossil-fueled economic growth spurt happened not because the energy industry created many jobs, but because it created very few jobs.

For most of human history, providing energy in the form of food calories was the major human occupation. Even in societies that consumed relatively high amounts of energy via firewood, harvesting and transporting that wood kept a lot of people busy.

But during the 19th and 20th centuries, as the available per capita energy supply in industrialized countries exploded, the proportion of the population employed supplying that energy dropped dramatically.

The result: instead of farming to provide the carbohydrates that feed humans and oxen, or cutting firewood to heat buildings, nearly the whole population has been free to do other activities. Whether we have made good use of this opportunity is debatable, but we’ve had plenty of energy, and nearly our entire labour force, available to run an elaborate manufacturing, consumption and service economy.

Seen from this perspective, the claim that renewable energy will create more jobs might set off alarms.

What’s in a job?

Part of the difficulty is that when we speak of a job, we refer to two (or more) very different things.

A job might mean simply something that has to be done. In this sense of the word, we don’t usually celebrate jobs. If we need to carry all our water in buckets from a well five kilometers from home, there are a lot of jobs in water-carrying – but we would probably welcome having taps right in our kitchens instead. Agriculture employs a lot of people if the only tools are sticks, but with better tools the same amount of food can be raised with fewer people working the fields.

So when we think of a job as the need to do something, we typically think that the fewer jobs the better.

When we celebrate job-creation, on the other hand, we typically mean something quite different –  a “job” is an activity that is accompanied by a pay-cheque. Since in our society most of us need to get pay-cheques for most of our lives, job-creation strikes us as a good thing to the extant that pay-cheques are involved.

Here’s the wrinkle with renewable energy job creation: the renewable energy transition will likely create jobs in the sense of adding to the quantity of work that must be done (which we normally try to minimize) and jobs in the sense of providing pay-cheques (which we typically want to maximize). The two types of job-creation are at cross-purposes, and the outcome is uncertain.

Allocation of energy surplus

Widespread prosperity depends not only on what work is done and what surplus is produced, but on how that surplus is allocated and distributed.

In the middle of the 20th century in North America and Europe, only a few people worked in energy supply but they produced a huge surplus. At the same time, the products of surplus energy were distributed in relatively equal fashion, compared to the rising levels of inequality today. The mass consumption economy – a brief anomaly in human history which is ironically referred to as Business As Usual – depended on both conditions being met. There had to be a large surplus of energy produced (or, more accurately, extracted) by a few people, and this surplus energy had to be widely distributed so that most people could participate in a consumer economy.

Naomi Klein gives prominent emphasis to the second of these two conditions. In her CBC Radio Ideas talk, she says

There’s a group in the US called Movement Generation which has a slogan that I quote a lot, which is that “transition is invevitable, but justice is not.” You can respond to climate change in a way that people putting up solar panels are paid terrible wages. In the US prison inmates are making some of the solar panels that they’re putting up. … There has to be a road map for responding to climate change in an intersectional way, which solves multiple problems at once.”

She cites the German Energy Transition as an encouraging example:

There are 900 new energy co-operatives that have sprung up in Germany. Two hundred towns and cities in Germany have taken their energy grids back from the private companies that took them over in the 1990s, and they call it “energy democracy”. They’re taking back control over their energy, so that the resources stay in the communities and they can use the profits generated from renewable energy to pay for services. They’ve also created 400,000 jobs as part of this transition. So they’re showing how you solve multiple problems at once. Lower emissions create good unionized jobs and generate the revenue we need to fight the logic of austerity at the local level.”

In Klein’s formulation, democratic control of the energy economy is a key to prosperity. Because of this energy democracy, the new jobs are “good unionized jobs” which “fight the logic of austerity”. But is that sustainable in the long run?

As Klein says, in Germany’s “energy democracy” they use “the profits generated from renewable energy to pay for services”. But that presupposes that the renewable energy technologies being used do indeed generate “profits”.

It remains an open question how much profit – how much surplus energy – will be generated from renewable energy development. If renewable energy developments consume nearly as much energy as they produce, then in the long run the energy sector may produce many pay-cheques but they won’t be generous pay-cheques, however egalitarian society might be.

Book cover, Life After Growth by Tim MorganEnergy sprawl

Tim Morgan uses the apt phrase “energy sprawl” to describe what happens as we switch to energy technologies with a lower Energy Return on Energy Invested (EROEI).

‘energy sprawl’ … has both physical and economic meanings. In physical terms, the infrastructure required to access energy and deliver it to where it is needed is going to expand exponentially. At the same time, the proportion of GDP absorbed by the energy infrastructure is going to increase as well, which means that the rest of the economy will shrink.” (Life After Growth, Harriman House, 2013, locus 2224)

As Morgan makes clear, energy sprawl is not at all unique to renewable energy transition – it applies equally to non-conventional, bottom-of-the-barrel fossil fuels such as fracked oil and gas, and bitumen extracted from Alberta’s tar sands. There will indeed be more jobs in a renewable resource economy, compared to the glory days of the fossil fuel economy, but there will also be more energy jobs if we cling to fossil fuels.

As energy sprawl proceeds, more of us will work in energy production and distribution, and fewer of us will be free to work at other pursuits. As Klein and the other authors of the Leap Manifesto argue, the higher number of energy jobs might be a net plus for society, if we use energy more wisely AND we allocate surplus more equitably.

But unless our energy technologies provide a good Energy Return On Energy Invested, there will be little surplus to distribute. In other words, there will be lots of new jobs, but few good pay-cheques.

Top photo: Canadian author and activist Naomi Klein, photographed by Joe Mabel in October 2015, accessed via Wikimedia Commons

Oil well in southeast Saskatchewan, with flared gas.

Energy at any cost?

Also published at

If all else is uncertain, how can growing demand for energy be guaranteed? A review of Vaclav Smil’s Natural Gas.

Near the end of his 2015 book Natural Gas: Fuel for the 21st Century, Vaclav Smil makes two statements which are curious in juxtaposition.

On page 211, he writes:

I will adhere to my steadfast refusal to engage in any long-term forecasting, but I will restate some basic contours of coming development before I review a long array of uncertainties ….”

Link to Vaclav Smil series list.And in the next paragraph:

Given the scale of existing energy demand and the inevitability of its further growth, it is quite impossible that during the twenty-first century, natural gas could come to occupy such a dominant position in the global primary energy supply as wood did in the preindustrial era or as coal did until the middle of the twentieth century.”

If you think that second statement sounds like a long-term forecast, that makes two of us. But apparently to Smil it is not a forecast to say that the growth of energy demand is inevitable, and it’s not a forecast to state with certainty that natural gas cannot become the dominant energy source during the twenty-first century – these are simply “basic contours of coming development.” Let’s investigate.

An oddly indiscriminate name

Natural Gas is a general survey of the sources and uses of what Smil calls the fuel with “an oddly indiscriminate name”. It begins much as it ends: with a strongly-stated forecast (or “basic contour”, if you prefer) about the scale of natural gas and other fossil fuel usage relative to other energy sources.

why dwell on the resources of a fossil fuel and why extol its advantages at a time when renewable fuels and decentralized electricity generation converting solar radiation and wind are poised to take over the global energy supply. That may be a fashionable narrative – but it is wrong, and there will be no rapid takeover by the new renewables. We are a fossil-fueled civilization, and we will continue to be one for decades to come as the pace of grand energy transition to new forms of energy is inherently slow.” – Vaclav Smil, preface to Natural Gas

And in the next paragraph:

Share of new renewables in the global commercial primary energy supply will keep on increasing, but a more consequential energy transition of the coming decades will be from coal and crude oil to natural gas.”

In support of his view that a transition away from fossil fuel reliance will take at least several decades, Smil looks at major energy source transitions over the past two hundred years. These transitions have indeed been multi-decadal or multi-generational processes.

Obvious absence of any acceleration in successive transitions is significant: moving from coal to oil has been no faster than moving from traditional biofuels to coal – and substituting coal and oil by natural gas has been measurably slower than the two preceding shifts.” – Natural Gas, page 154

It would seem obvious that global trade and communications were far less developed 150 years ago, and that would be one major reason why the transition from traditional biofuels to coal proceeded slowly on a global scale. Smil cites another reason why successive transitions have been so slow:

Scale of the requisite transitions is the main reason why natural gas shares of the TPES [Total Primary Energy System] have been slower to rise: replicating a relative rise needs much more energy in a growing system. … going from 5 to 25% of natural gas required nearly eight times more energy than accomplishing the identical coal-to-oil shift.” – Natural Gas, page 155

Open-pit coal mine in south-east Saskatchewan.

Open-pit coal mine in south-east Saskatchewan. June 2014.

Today only – you’ll love our low, low prices!

There is another obvious reason why transitions from coal to oil, and from oil to natural gas, could have been expected to move slowly throughout the last 100 years: there have been abundant supplies of easily accessible, and therefore cheap, coal and oil. When a new energy source was brought online, the result was a further increase in total energy consumption, instead of any rapid shift in the relative share of different sources.

The role of price in influencing demand is easy to ignore when the price is low. But that’s not a condition we can count on for the coming decades.

Returning to Smil’s “basic contour” that total energy demand will inevitably rise, that would imply that energy prices will inevitably remain relatively low – because there is effective demand for a product only to the extent that people can afford to buy it.

Remarkably, however, even as he states confidently that demand must grow, Smil notes the major uncertainty about the investment needed simply to maintain existing levels of supply:

if the first decade of the twenty-first century was a trendsetter, then all fossil energy sources will cost substantially more, both to develop new capacities and to maintain production of established projects at least at today’s levels. … The IEA estimates that between 2014 and 2035, the total investment in energy supply will have to reach just over $40 trillion if the world is to meet the expected demand, with some 60% destined to maintain existing output and 40% to supply the rising requirements. The likelihood of meeting this need will be determined by many other interrelated factors.” – Natural Gas, page 212

What is happening here? Both Smil and the IEA are cognizant of the uncertain effects of rising prices on supply, while graphing demand steadily upward as if price has no effect. This is not how economies function in the real world, of course.

Likewise, we cannot assume that because total energy demand kept rising throughout the twentieth century, it must continue to rise through the twenty-first century. On the contrary, if energy supplies are difficult to access and therefore much more costly, then we should also expect demand to grow much more slowly, to stop growing, or to fall.

Falling demand, in turn, would have a major impact on the possibility of a rapid change in the relative share of demand met by different sources. In very simple terms, if we increased total supply of renewable energy rapidly (as we are doing now), but the total energy demand were dropping rapidly, then the relative share of renewables in the energy market could increase even more rapidly.

Smil’s failure to consider such a scenario (indeed, his peremptory dismissal of the possibility of such a scenario) is one of the major weaknesses of his approach. Acceptance of business-as-usual as a reliable baseline may strike some people as conservative. But there is nothing cautious about ignoring one of the fundamental factors of economics, and nothing safe in assuming that the historically rare condition of abundant cheap energy must somehow continue indefinitely.

In closing, just a few words about the implications of Smil’s work as it relates to the threat of climate change. In Natural Gas, he provides much valuable background on the relative amounts of carbon emissions produced by all of our major energy sources. He explains why natural gas is the best of the fossil fuels in terms of energy output relative to carbon emissions (while noting that leaks of natural gas – methane – could in fact outweigh the savings in carbon emissions). He explains that the carbon intensity of our economies has dropped as we have gradually moved from coal to oil to natural gas.

But he also makes it clear that this relative decarbonisation has been far too slow to stave off the threat of climate change.

If he turns out to be right that total energy demand will keep rising, that there will only be a slow transition from other fossil fuels to natural gas, and that the transition away from all fossil fuels will be slower still, then the chances of avoiding catastrophic climate change will be slim indeed.

Top photo: Oil well in southeast Saskatchewan, with flared gas. June 2014.

Wind turbine on site of Pickering Nuclear Generating Station.

How big is that hectare? It depends.

Also published at

link to Accounting For Energy seriesThe Pickering Nuclear Generating Station, on the east edge of Canada’s largest city, Toronto, is a good take-off point for a discussion of the strengths and limitations of Vaclav Smil’s power density framework.

The Pickering complex is one of the older nuclear power plants operating in North America. Brought on line in 1971, the plant includes eight CANDU reactors (two of which are now permanently shut down). The complex also includes a single wind turbine, brought online in 2001.

Wonkometer-225The CANDU reactors are rated, at full power, at about 3100 Megawatts (MW). The wind turbine, which at 117 meters high was one of North America’s largest when it was installed, is rated at 1.8 MW at full power. (Because the nuclear reactor runs at full power for many more hours in a year, the disparity in actual output is even greater than the above figures suggest.)

How do these figures translate to power density, or power per unit of land?

The Pickering nuclear station stands cheek-by-jowl with other industrial sites and with well-used Lake Ontario waterfront parks. With a small land footprint, its power density is likely towards the high end – 7,600 W/m2 – of the range of nuclear generating stations Smil considers in Power Density. Had it been built with a substantial buffer zone, as is the case with many newer nuclear power plants, the power density might only be half as high.

A nuclear power plant, of course, requires a complex fuel supply chain that starts at a uranium mine. To arrive at more realistic power density estimates, Smil considers a range of mining and processing scenarios. When a nuclear station’s output is prorated over all the land used – land for the plant site itself, plus land for mining, processing and spent fuel storage – Smil estimates a power density of about 500 W/m2 in what he considers the most representative, mid-range of several examples.

Cameco uranium processing plant in Port Hope, Ontario

The Cameco facility in Port Hope, Ontario processes uranium for nuclear reactors. With no significant buffer around the plant, its land area is small and its power density high. Smil calculates its conversion power density at approximately 100,000 W / square meter, with the plant running at 50% capacity.

And wind turbines? Smil looks at average outputs from a variety of wind farm sites, and arrives at an estimated power density of about 1 W/m2.

So nuclear power has about 500 times the power density of wind turbines? If only it were that simple.

Inside and outside the boundary

In Power Density, Smil takes care to explain the “boundary problem”: defining what is being included or excluded in an analysis. With wind farms, for example, which land area is used in the calculation? Is it just the area of the turbine’s concrete base, or should it be all the land around and between turbines (in the common scenario of a large cluster of turbines spaced throughout a wind farm)?  There is no obviously correct answer to this question.

On the one hand, land between turbines can be and often is used as pasture or as crop land. On the other hand, access roads may break up the landscape and make some human uses impractical, as well as reducing the viability of the land for species that require larger uninterrupted spaces. Finally, there is considerable controversy about how close to wind turbines people can safely live, leading to buffer zones of varying sizes around turbine sites. Thus in this case the power output side of the quotient is relatively easy to determine, but the land area is not.

Wind turbines in southwestern Minnesota

Wind turbines line the horizon in Murray County, Minnesota, 2012.

Smil emphasizes the importance of clearly stating the boundary assumptions used in a particular analysis. For the average wind turbine power density of 1 W/m2, he is including the whole land area of a wind farm.

That approach is useful in giving us a sense of how much area would need to be occupied by wind farms to produce the equivalent power of a single nuclear power plant. The mid-range power station cited above (with overall power density of 500 W/m2) takes up about 1360 hectares in the uranium mining-processing-generating station chain. A wind farm of equivalent total power output would sprawl across 680,000 hectares of land, or 6,800 square kilometers, or a square with 82 km per side.

A wind power evangelist, on the other hand, could argue that the wind farms remain mostly devoted to agriculture, and with the concrete bases of the towers only taking 1% of the wind farm area, the power density should be calculated at 100 instead of 1W/m2.

Similar questions apply in many power density calculations. A hydro transmission corridor takes a broad stripe of countryside, but the area fenced off for the pylons is small. Most land in the corridor may continue to be used for grazing, though many other land uses will be off-limits. So you could use the area of the whole corridor in calculating power density – plus, perhaps, another buffer on each side if you believe that electromagnetic fields near power lines make those areas unsafe for living creatures. Or you could use just the area fenced off directly around the pylons. The respective power densities will vary by orders of magnitude.

If the land area is not simple to quantify when things go right, it is even more difficult when things go wrong. A drilling pad for a fracked shale gas may only be a hectare or two, so during the brief decade or two of the well’s productive life, the power density is quite high. But if fracking water leaks into an aquifer, the gas well may have drastic impacts on a far greater area of land – and that impact may continue even when the fracking boom is history.

The boundary problem is most tangled when resource extraction and consumption effects have uncertain extents in both space and time. As mentioned in the previous installment in this series, sometimes non-renewable energy facilities can be reclaimed for a full range of other uses. But the best-case scenario doesn’t always apply.

In mountain-top removal coal mining, there is a wide area of ecological devastation during the mining. But once the energy extraction drops to 0 and the mining corporation files bankruptcy, how much time will pass before the flattened mountains and filled-in valleys become healthy ecosystems again?

Or take the Pickering Nuclear Generation Station. The plant is scheduled to shut down about 2020, but its operators, Ontario Power Generation, say they will need to allow the interior radioactivity to cool for 15 years before they can begin to dismantle the reactor. By their own estimates the power plant buildings won’t be available for other uses until around 2060. Those placing bets on whether this will all go according to schedule can check back in 45 years.

In the meantime the plant will occupy land but produce no power; should the years of non-production be included in calculating an average power density? If decommissioning fails to make the site safe for a century or more, the overall power density will be paltry indeed.

In summary, Smil’s power density framework helps explain why it has taken high-power-density technologies to fuel our high-energy-consumption society, even for a single century. It helps explain why low power density technologies, such as solar and wind power, will not replace our current energy infrastructure or current demand for decades, if ever.

But the boundary problem is a window on the inherent limitations of the approach. For the past century our energy has appeared cheap and power densities have appeared high. Perhaps the low cost and the high power density are both due, in significant part, to important externalities that were not included in calculations.

Top photo: Pickering Nuclear Generating Station site, including wind turbine, on the shoreline of Lake Ontario near Toronto.

Insulators on high-voltage electricity transmission line.

Timetables of power

Also published at

accounting_for_energy_2For more than three decades, Vaclav Smil has been developing the concepts presented in his 2015 book Power Density: A Key to Understanding Energy Sources and Uses.

The concept is (perhaps deceptively) simple: power density, in Smil’s formulation, is “the quotient of power and land area”. To facilitate comparisons between widely disparate energy technologies, Smil states power density using common units: watts per square meter.

Wonkometer-225Smil makes clear his belief that it’s important that citizens be numerate as well as literate, and Power Density is heavily salted with numbers. But what is being counted?

Perhaps the greatest advantage of power density is its universal applicability: the rate can be used to evaluate and compare all energy fluxes in nature and in any society. – Vaclav Smil, Power Density, pg 21

A major theme in Smil’s writing is that current renewable energy resources and technologies cannot quickly replace the energy systems that fuel industrial society. He presents convincing evidence that for current world energy demand to be supplied by renewable energies alone, the land area of the energy system would need to increase drastically.

Study of Smil’s figures will be time well spent for students of many energy sources. Whether it’s concentrated solar reflectors, cellulosic ethanol, wood-fueled generators, fracked light oil, natural gas or wind farms, Smil takes a careful look at power densities, and then estimates how much land would be taken up if each of these respective energy sources were to supply a significant fraction of current energy demand.

This consideration of land use goes some way to addressing a vacuum in mainstream contemporary economics. In the opening pages of Power Density, Smil notes that economists used to talk about land, labour and capital as three key factors in production, but in the last century, land dropped out of the theory.

The measurement of power per unit of land is one way to account for use of land in an economic system. As we will discuss later, those units of land may prove difficult to adequately quantify. But first we’ll look at another simple but troublesome issue.

Does the clock tick in seconds or in centuries?

It may not be immediately obvious to English majors or philosophers (I plead guilty), but Smil’s statement of power density – watts per square meter – includes a unit of time. That’s because a watt is itself a rate, defined as a joule per second. So power density equals joules per second per square meter.

There’s nothing sacrosanct about the second as the unit of choice. Power densities could also be calculated if power were stated in joules per millisecond or per megasecond, and with only slightly more difficult mathematical gymnastics, per century or per millenium. That is of course stretching a point, but Smil’s discussion of power density would take on a different flavor if we thought in longer time frames.

Consider the example with which Smil opens the book. In the early stages of the industrial age, English iron smelting was accomplished with the heat from charcoal, which in turn was made from coppiced beech and oak trees. As pig iron production grew, large areas of land were required solely for charcoal production. This changed in the blink of an eye, in historical terms, with the development of coal mining and the process of coking, which converted coal to nearly 100% pure carbon with energy equivalent to good charcoal.

As a result, the charcoal from thousands of hectares of hardwood forest could be replaced by coal from a mine site of only a few hectares. Or in Smil’s favored terms,

The overall power density of mid-eighteenth-century English coke production was thus roughly 500 W/m2, approximately 7,000 times higher than the power density of charcoal production. (Power Density, pg 4)

Smil notes rightly that this shift had enormous consequences for the English countryside, English economy and English society. Yet my immediate reaction to this passage was to cry foul – there is a sleight of hand going on.

While the charcoal production figures are based on the amount of wood that a hectare might produce on average each year, in perpetuity, the coal from the mine will dwindle and then run out in a century or two. If we averaged the power densities of the woodlot and mine over several centuries or millennia, the comparison look much different.

And that’s a problem throughout Power Density. Smil often grapples with the best way to average power densities over time, but never establishes a rule that works well for all energy sources.

Generating station near Niagara Falls

The Toronto Power Generating Station was built in 1906, just upstream from Horseshoe Falls in Niagara Falls, Ontario. It was mothballed in 1974. Photographed in February, 2014.

In discussing photovoltaic generation, he notes that solar radiation varies greatly by hour and month. It would make no sense to calculate the power output of a solar panel solely by the results at noon in mid-summer, just as it would make no sense to run the calculation solely at twilight in mid-winter. It is reasonable to average the power density over a whole year’s time, and that’s what Smil does.

When considering the power density of ethanol from sugar cane, it would be crazy to run the calculation based solely on the month of harvest, so again, the figures Smil uses are annual average outputs. Likewise, wood grown for biomass fuel can be harvested approximately every 20 years, so Smil divides the energy output during a harvest year by 20 to arrive at the power density of this energy source.

Using the year as the averaging unit makes obvious sense for many renewable energy sources, but this method breaks down just as obviously when considering non-renewable sources.

How do you calculate the average annual power density for a coal mine which produces high amounts of power for a hundred years or so, and then produces no power for the rest of time? Or the power density of a fracked gas well whose output will continue only a few decades at most?

The obvious rejoinder to this line of questioning is that when the energy output of a coal mine, for example, ceases, the land use also ceases, and at that point the power density of the coal mine is neither high nor low nor zero; it simply cannot be part of a calculation. As we’ll discuss later in this series, however, there are many cases where reclamations are far from certain, and so a “claim” on the land goes on.

Smil is aware of the transitory nature of fossil fuel sources, of course, and he cites helpful and eye-opening figures for the declining power densities of major oil fields, gas fields and coal mines over the past century. Yet in Power Density, most of the figures presented for non-renewable energy facilities apply for that (relatively brief) period when these facilities are in full production, but they are routinely compared with power densities of renewable energy facilities which could continue indefinitely.

So is it really true that power density is a measure “which can be used to evaluate and compare all energy fluxes in nature and in any society”? Only with some critical qualifications.

In summary, we return to Smil’s oft-emphasized theme, that current renewable resource technologies are no match for the energy demands of our present civilization. He argues convincingly that the power density of consumption on a busy expressway will not be matched to the power density of production of ethanol from corn: it would take a ridiculous and unsustainable area of corn fields to fuel all that high-energy transport. Widening the discussion, he establishes no less convincingly, to my mind, that solar power, wind power, and biofuels are not going to fuel our current high-energy way of life.

Yet if we extend our averaging units to just a century or two, we could calculate just as convincingly that the power densities of non-renewable fuel sources will also fail to support our high-energy society. And since we’re already a century into this game, we might be running out of time.

Top photo: insulators on high-voltage transmission line near Darlington Nuclear Generating Station, Bowmanville, Ontario.