Sunday, January 29, 2023

Energy Isn't an End in Itself

Ezra Klein of the New York Times has a recent opinion column advocating for a future in which people everywhere use many times more energy than Americans use today. The column is largely inspired by J. Storrs Hall’s book Where Is My Flying Car?, along with other writers who have been promoting what they call “energy abundance”.

Before I explain how wrongheaded Klein’s column is, let me say what I like about it.

I absolutely agree that “Where’s my flying car?” is a legitimate question. I would even call it a fascinating question—though not, ultimately, a very important question.

I also agree with Klein’s incisive criticisms of Hall’s sociopolitical theories. Rather than review those here, I’ll just refer you to Klein, who’s far better than I am with words.

Finally, I agree that poverty is a huge problem in most parts of the world and that bringing everyone out of poverty will entail a pretty big jump in global energy use.

But by “pretty big” I mean something like a factor of 2, not a factor of 20. The world per-capita energy use rate is currently about 2.5 kilowatts. Ending widespread poverty throughout the world will roughly double that number, bringing it up to the current level in western Europe and Japan, about 4 to 5 kW.

Klein is trying to envision a world in which per-capita energy use doubles three more times, then grows even further by unspecified amounts. The first of these additional doublings would bring the world up to the current per-capita energy use rate in the United States, 9 kW. The next doubling would bring the world up to about 20 kW per capita, the current rate in a few small industry-heavy countries such as Iceland and Qatar. The third doubling would take us to 40 kW per capita, a level of energy use that no country on earth has ever experienced. A recent report from a think tank called The Center for Growth and Opportunity, cited favorably by Klein, defines 40 kW per capita as “energy superabundance” and advocates for such a goal. Yet Klein refers to this goal as “fairly modest”, touting the idea of using still more energy.

So what’s wrong with aspiring to use enormous amounts of energy? Just two things: There’s no known reason to do so, and there’s no known energy source that’s free of unwanted side effects.

Before explaining the first of these points in some detail, let me briefly address the second. The only known energy sources that can conceivably scale up to a significant percentage of 40 kW per capita—that is, 400 terawatts globally—are wind (maybe), solar, and nuclear energy. (Sorry, geothermal resources are too limited to sustainably contribute tens of terawatts.) Wind or solar generation on that scale would take over vast stretches of earth’s surface that many people would prefer to reserve for other uses. Nuclear energy on that scale, whether fission or fusion, would produce enough excess heat to vie with the effects of anthropogenic greenhouse gases on a regional, if not global, scale.

So even “clean” energy sources have unavoidable costs. The question then becomes whether there are benefits that make these costs worthwhile.

Why use more energy?

Merely using more energy provides no intrinsic benefit. I could add massive amounts to my personal energy use just by opening the windows in January and cranking up the thermostat. As Amory Lovins famously said, “People don’t want raw kilowatt-hours or lumps of coal or barrels of sticky black goo. They want hot showers, cold beer, comfort, mobility, illumination.”

Energy is a useful abstraction because we can often substitute one energy source for another: coal for wood, natural gas for coal, wind for natural gas. When we make such a substitution, we can estimate how much of the new source we need by equating its energy content to that of the old source. But real-world complications quickly arise in the actual machinery that captures the energy and transmits it and puts it to use. Energy gets lost as waste heat, in steam turbines and automobile engines and chimneys and incandescent bulbs and open windows. Different technologies can produce the same benefit with vastly different amounts of waste.

So although it pains me, as a physicist, to say this, energy per se is not as fundamental to human needs as Klein and others seem to think.

Klein seems to believe that energy itself is more important than what we use it for. He writes that we can choose among three possible goals as a society: use less energy, or use the same amount, or use more. In fact none of these goals make any sense. It’s wrongheaded to treat energy as an end in itself. The sensible goals are hot showers, cold beer, and so on.

OK, so what about those kinds of goals? Klein lists some particular energy uses that would supposedly become possible if we just had more energy. Much of his list is standard fare among “abundance” advocates: desalination to obtain fresh water; indoor farming with artificial light; capturing carbon dioxide directly from the air. Like his predecessors (at least all those I’m aware of), Klein makes no attempt to do the math to determine whether any of these activities will ever be practical—or desirable—on a scale that would add more than a few percent onto global energy consumption. Desalination, for instance, already provides most of Israel’s municipal water supply, yet adds just 5% to that country’s electricity use.

To this standard list Klein then adds nanotechnology, but here he seems to be misreading Hall. Yes, Hall complains ad nauseam about the slow pace at which nanotechnology has developed in recent decades, supposedly depriving us of all sorts of technological miracles. But nanotechnology isn’t a big energy consumer, and even Hall never suggests that the reason why it hasn’t advanced more rapidly has anything to do with limited energy supplies. Klein implies that it does. Maybe he has some convoluted, unwritten reasoning to back up the claim, but I suspect he’s just confused.

Finally there’s transportation—specifically, aviation and space travel. Hall claims that these technologies have been held back, since the 1970s, by “ergophobia”—fear of using energy. Klein suggests (again without doing any of the math) that if we just had enough energy, virtually everyone on earth would be using it to fly hundreds or thousands of miles a day. Is any of this plausible?

I don’t think so. It’s true that aviation and space travel both require a lot of energy per passenger, but neither is being held back by fuel shortages or even by fuel costs. Less than one percent of the total cost of a Space Shuttle launch was for rocket fuel. For commercial jet flights the fuel cost percentage is higher (typically about 20%), but still not dominant.

The more important role that energy plays in limiting aviation and space travel is indirect. The kinetic and gravitational energies maintained during flight make it intrinsically dangerous—and it’s perfectly rational to be “ergophobic” about that danger. There are ways to mitigate the risks of flying, and the safety record of commercial jet travel is a miracle of the modern world. But risk mitigation comes at a high cost, both in dollars and in convenience: pilot licensing rules, maintenance requirements, air space restrictions, airport security screenings, and so on. People will inevitably disagree over how much risk to accept in exchange for reducing those costs, but let’s not confuse the cost of safety with the cost of fuel.

In summary, it is a logical fallacy to argue that merely supplying the needed energy would give us the world that Klein envisions, in which billions of people commute between continents on a daily basis. Besides the challenges of safety and convenience (and counteracting gravity in the first place), it’s just not clear how many people would voluntarily choose such a lifestyle. Most Americans today could afford to travel more than they actually do, but find life less hectic and more meaningful when they put down roots and spend plenty of time close to home.

Rewriting energy history

Although Klein’s column is ostensibly about the future, his rhetoric relies on comparisons to the past. Such comparisons are all too tempting, because no sane person today wants to go back to the awful living conditions our ancestors had to endure.

But Klein mangles the facts about past energy use.

The most eye-popping howler in Klein’s column is his claim that “Across the 18th, 19th and 20th centuries, the energy humanity could harness grew at about 7 percent annually.” He says this in the context of describing Hall’s book, which contains a somewhat similar claim. Hall’s version is exaggerated badly enough. Klein’s version is far worse.

The words “across” and “harness” are somewhat vague, so there’s no unique way to correct Klein’s claim, but no reasonable interpretation of it is anywhere close to true. If we’re talking about the growth in global primary energy use from 1700 through 2000, then the average annual increase was actually about 1.2%, not 7%. With 300 years of compounding, this means the overall increase was by a factor of about 40, whereas Klein’s 7% would imply a growth factor of (brace yourself!) 650,000,000. (The 1.2% annual increase breaks down into a population growth rate of about 0.8% and an energy-per-capita growth rate of about 0.4%.) Even during the 20th century, when energy use grew more rapidly, the average annual growth rate of global energy use was only 2.3% (again about 2/3 from population growth and 1/3 from energy-per-capita growth). There have been shorter time periods over which world energy use grew somewhat more rapidly, but “7 percent annually” over “centuries” is a ridiculous claim.

Hall, for what it’s worth, arrives at his 7% annual growth figure by looking not at all of humanity but only at “our civilization”—by which he seems to mean the United States since 1800, and perhaps Great Britain during the century or so before that. He plots a graph purporting to show a 2% annual growth rate in U.S. per-capita energy use from 1800 through 1979, although it actually shows an average growth rate of less than 1% over that time period. He then compounds the alleged 2% per-capita energy use growth with an alleged population growth rate of 3% (also exaggerated from the actual U.S. value of about 2% over this time period), to obtain a claimed 5% growth rate in “our civilization’s” total energy use. Finally he adds on a 2% “energy efficiency growth rate” (which he obtains by extrapolating from a much narrower data set), to get a purported 7% growth rate in “usable” energy. (Perhaps Klein intends “could harness” to imply the incorporation of some kind of growing efficiency factor. If so he has not made that clear, nor has he incorporated any such factor into his article’s other energy figures.)

In fact the only way to arrive at anything close to a 7% annual energy growth rate over multiple centuries—for the world or any large portion of it—is to arbitrarily define “energy” to exclude the wood and other biomass energy that accounted for nearly all energy use before the Industrial Revolution. That’s what Hall has actually done, as he confesses on his blog. If humanity’s energy use in 1700 was zero by definition, then it has grown since then by a factor of infinity! Does Klein (who calls Hall’s technical analyses “careful”) realize that he’s propagating this foolishness on Hall’s part? We have no way to tell.

But then Klein does it again, this time with a misleading paraphrase from Charles Mann’s book The Wizard and the Prophet:

Without energy, even material splendor has sharp limits. Mann notes that visitors to the Palace of Versailles in February 1695 marveled at the furs worn to dinners with the king and the ice that collected on the glassware. It was freezing in Versailles, and no amount of wealth could fix it. A hundred years later, Thomas Jefferson had a vast wine collection and library in Monticello and the forced labor of hundreds of slaves, but his ink still froze in his inkwells come winter.

Were King Louis XIV and Thomas Jefferson truly “without energy”? Of course not! The Palace of Versailles has 1200 fireplaces, and surely the king could afford to keep them supplied with wood. The fireplace count at the much smaller Monticello is just 8, but they consumed 10 cords of wood per month, which would have provided about 200 million Btu of energy. The same energy in the form of natural gas would now cost you about $3600. Louis XIV and Jefferson weren’t lacking energy. They were lacking efficient central heating systems that capture most of the energy before it goes up the chimney.

Today’s American homes are not merely better heated and better lit than in Thomas Jefferson’s day. We also have refrigerators, air conditioners, hot running water, automatic washers and dryers, electronic entertainment systems, and a cornucopia of other energy-hungry appliances. And our homes have grown, doubling (at least) in square footage per capita. Yet astoundingly, we use less energy per capita in our homes today than Americans used in 1800. How efficiently we use energy can be more important than how much energy we use.

These historical facts about energy use don’t get discussed much, so perhaps we shouldn’t be shocked that Klein could get them so wrong. Still, I would expect someone who writes for such a large audience to consult a knowledgable expert for some basic fact-checking. It’s unfortunate that the New York Times allows its opinion columnists to spread falsehoods that are so easily refuted.

Why promote energy use as a goal?

When smart people misstate facts, even unintentionally, it’s natural to ask why. So I’d like to end this essay by considering some of the possible incentives, motives, and goals of the “energy abundance” movement. Why are so many writers currently pushing the idea that increased energy use is a moral good—a worthy end in itself?

One incentive for virtually every writer these days is to attract readers, generate clicks, and sell subscriptions or books. To do that it helps to say things that are surprising and provocative, not banal and reasonable. Fuel a culture war whenever possible.

It also helps to say things that readers want to hear. Many Americans are understandably tired of being scolded for using too much energy. They’re eager to believe that the scolds were wrong.

But there are plenty of subjects that can arouse readers’ emotions. Why “energy abundance” in particular?

For any intellectual there is a natural urge to understand broad swaths of the world in terms of a few deep principles: to devise a Grand Unified Theory of How the World Works. The so-called “abundance agenda”, as articulated by Klein’s collaborator Derek Thompson (in an article modestly titled “A Simple Plan to Solve All of America’s Problems”), seems to be a proposal for such a theory. We need (Thompson says) an abundance not just of energy but also of housing, infrastructure, immigrants, COVID tests, and admission slots at elite colleges.

As a physicist I’m all too familiar with the temptation to devise Grand Unified Theories. But I also know that virtually all of these theories turn out to be wrong (or sometimes “not even wrong”, that is, too vague to make testable predictions). The world of human affairs is vastly more complex than that of fundamental physics, so we should be even more skeptical of Grand Unified Theories in the social realm. A theory that works beautifully in one situation can still fail badly in another, so we shouldn’t become too attached to any particular Grand Unified Theory. In the language of Archilochus and Isaiah Berlin, we should try to think like foxes, not hedgehogs.

At least that’s my opinion. The “abundance agenda” folks are obviously trying to be hedgehogs.

Of course there’s also a Grand Unified Theory that’s opposite to the abundance agenda: what we could call the “scarcity agenda” of those who preach about limited resources and living within our means. That way of thinking had its heyday when I was growing up during the 1970s, and is still prevalent among environmental activists and many academics. Like the “abundance agenda”, it’s a correct and useful viewpoint in some circumstances but fails badly in others. So a worthwhile motive for the energy abundance tribe would be to counteract the worst excesses of the energy scarcity tribe. I think that probably is part of their motivation, even if they go beyond it to indulge in their own excesses.

There’s one further motivation that I think underlies some, though not all, of the recent literature on “energy abundance”. The Center for Growth and Opportunity, whose “Energy Superabundance” report Klein cites for its energy use rate goal of 40 kW per capita, was established (at Utah State University in 2017) by a $25 million grant from the Charles Koch Foundation. Although the Center denies that its activities are “directed or influenced in any way” by its donors, Charles Koch’s fortune came from oil and he makes no secret of his libertarian political agenda.

After decades of casting doubt on climate science, fossil fuel interests have learned that that tactic is no longer acceptable in polite society. How, then, can they promote continued growth of fossil fuel use? One effective way might be to spread the general message that we should use more energy.

Klein’s essay, of course, includes the perfunctory caveat that the energy we use in our utopian future should be “clean”. He even alludes to the “daunting” task of shifting our energy economy to “nonpolluting sources”. But the thrust of his essay is that energy has brought us wondrous gifts, and promises us new miracles to come, if only we’ll make every effort to use more of it. Seeing that message in the Opinion section of the New York Times surely brought a smile to the face of Charles Koch.