Author Archives: Gernot Wagner

Climate Shock in under 90 seconds

Think of the atmosphere as a giant bathtub. There’s a faucet—emissions from human activity—and a drain—the planet’s ability to absorb that pollution. For most of human civilization and hundreds of thousands of years before, the inflow and the outflow were in relative balance. Then humans started burning coal and turned on the faucet far beyond what the drain could handle. The levels of carbon in the atmosphere began to rise to levels last seen in the Pliocene, over three million years ago.

What to do? That’s the question John Sterman, an MIT professor, asked two hundred graduate students. More specifically, he asked what to do to stabilize concentrations of carbon dioxide in the atmosphere close to present levels. How far do we need to go in turning off the faucet in order to stabilize concentrations? Here’s what not to do: stabilizing the flow of carbon into the atmosphere today won’t stabilize the carbon already there at close to present levels. You’re still adding carbon. Just because the inflow remains steady year after year, doesn’t mean the amount already in the tub doesn’t go up. Inflow and outflow need to be in balance, and that won’t happen at current levels of carbon dioxide in the tub (currently at 400 ppm) unless the inflow goes down by a lot.

That seems like an obvious point. It also seems to get lost on the average MIT graduate student, and these students aren’t exactly 'average'. Still, over 80 percent of them in Sterman’s study seem to confuse the faucet with the tub. They confuse stabilizing the inflow with stabilizing the level.

Watch this video to avoid making the same mistake:

Excerpted from Climate Shock.

Posted in 1000 words, Climate science, International, Politics| Leave a comment

We need a climate insurance policy – now

Q&A with Karin Rives first published on EDF Voices.

Climate Shock

Before climate change gets so bad that we may be forced to “geoengineer” ourselves out of catastrophe, a new book—Climate Shock—suggests that we reframe the problem altogether.

Gernot Wagner, a lead senior economist at Environmental Defense Fund and co-author of the book, says we ought to look at climate change as a risk management problem and treat it as such. I had a chat with Gernot about the book he will release next week together with Martin L. Weitzman, a professor of economics at Harvard University.

Karin Rives: Many books have already been published on climate change. What’s new or different about Climate Shock?

Most everyone focuses on what we know about climate change. Our book is about what we don’t know.

Call it Nassim Nicholas Taleb’s “Black Swan,” or the Rumsfeldian “unknown unknowns”—a state of complete and dangerous uncertainty and unpredictability. Call it what you want, but it’s that tail that may yet wag us in the end.

What we know is bad. What we don’t know is potentially much worse. Climate, in the end, is a risk management issue. Just like homeowners take out insurance against fires and flooding, society needs insurance against climate change.

KR: So what do we know?

Last time the planet experienced as much carbon in its atmosphere as there is now, sea levels where up to 66 feet higher than they are today. Camels lived in Canada. That was more than 3 million years ago. The geological clock read “Pliocene.”

We certainly know enough to take reasoned action today. And almost everything we don’t know points in one and only one direction: that action is all the more urgent.

KR: Why do we need to read this book now?

The time to buy our insurance policy is now—while we still can. And I’m speaking both metaphorically and literally.

Insurance here, of course, is to avoid dumping carbon into the atmosphere. We pay to have our trash picked up instead of just dumping it for free onto our streets. We similarly need to pay to avoid dumping carbon into our atmosphere.

That’s not free, but it’s still relatively cheap to do—and much cheaper than experiencing the consequences of unchecked global warming.

KR: What should be my three most important takeaways from your book?

Scream, cope, and profit.

We need to get the right policies in place, and soon. That’s “scream.” Then there’s some global warming we can no longer avoid—and that we are already experiencing. Let’s prepare ourselves better for that.

“Profit” is, of course, what you would expect two economists to say, dollar signs in their eyes and all. All that starts with smart investment decisions. Green, clean, and lean isn’t just got for the planet. It’s also the right financial choice and we need to ensure that it is much more so going forward.

The main takeaway, in the end, is that this isn’t some artificial battle between capitalism and the climate. It’s not about sticking it to the man. It’s about sticking it to carbon.

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Reconsidering the Rebound Effect

By Kenneth Gillingham, David Rapson, and Gernot Wagner.

The Rebound Effect and Energy Efficiency PolicyThe rebound effect from improving energy efficiency has been widely discussed—from the pages of the New York Times and New Yorker to the halls of policy and to a voluminous academic literature. It’s been known for over a century and, on the surface, is simple to understand. Buy a more fuel-efficient car, drive more. Invent a more efficient bulb, use more light. If efficiency improves, the price of energy services will drop, inducing increased demand for those services. Consumers will respond, producers will respond, and markets will re-equilibrate. All of these responses can lead to reductions in the energy savings expected from improved energy efficiency. And so some question the overall value of energy efficiency, by arguing that it will only lead to more energy use—a case often called "backfire."

In a new RFF discussion paper, "The Rebound Effect and Energy Efficiency Policy" we review the literature on the rebound effect, classify the different types, and highlight the need for careful distinction between causal links—which are indeed worthy of the “rebound” label—and mere correlations, which are not. We find, in fact, that measures to improve efficiency, despite potential rebound effects—are likely to improve welfare, generally.

Among the key questions about the rebound effect are a) whether the net benefits of energy efficiency increases are positive (for a costless improvement, the answer is almost certainly "yes"), and b) whether the increase in demand for energy services uses so much additional energy that it leads to greater, rather than less, demand for energy itself (the answer is almost certainly "no").

Our findings are clear: while it is possible for rebound effects to be large in some settings, there is no reliable evidence supporting rebound effects so large that improving energy efficiency leads to more energy use. Backfire is theoretically possible, but even the theoretical predictions rely on channels that are either a) second-order in magnitude (and thus unlikely to overwhelm primary effects), or b) lacking in empirical evidence of their existence and magnitude. Globally, we have little reason to worry about backfire. While there is much uncertainty about the size of the so-called "macroeconomic rebound" (how re-equilibration of markets and such hypothesized effects as induced innovation from the energy efficiency improvement may lead to a rebound), we consider a plausible upper bound of the total effect to be in the range of 60 percent (that is, 60 percent of the potential energy savings will be lost to rebound), with most studies pointing to a smaller effect.

Regardless of its size, we find that the rebound effect is very likely to be welfare-improving. In fact, in the extreme, energy efficiency improvements that come about from innovations or otherwise have no cost are unequivocally welfare-enhancing. If the improvements come with costs, such as air pollution from more driving or more expensive technology, those need to be weighed against the energy savings, emissions savings, and welfare benefits from the policy.

In short, undue emphasis on backfire is a mere distraction. Or as we put it in a recent letter to the editor of the New York Times: energy efficiency improvements such as "LEDs alone won’t solve global warming or global poverty, but they are a step in the right direction for both."

Published on Common Resources. The RFF Discussion Paper is here: "The Rebound Effect and Energy Efficiency Policy."

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Is energy efficiency a good thing even with rebound?

By Inês Azevedo, Kenneth Gillingham, David Rapson, and Gernot Wagner.

Lighting is critical to our livelihoods. Humans have used lighting technology since long before industrialization. For many centuries, this lighting was extremely inefficient, with over 95% of the energy consumed wasted as heat. Recently, the Nobel Prize in Physics was awarded to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura for their remarkable contributions towards highly efficient light emitting diode (LED) technology. A day later, Michael Shellenberger and Ted Nordhaus reignited a long standing debate with an Op-Ed in The New York Times claiming that these developments are not likely to save energy and instead may backfire. (TheTimes has since corrected a crucial point of the article, and it has published three letters to the editor, including one by a subset of co-authors here.)

As evidence for these claims, Shellenberger and Nordhaus cite research that observes the vast improvements in the efficiency of lighting over the past two centuries having resulted in “more and more of the planet [being] dotted with clusters of lights.” They take this as evidence of how newer and ever more efficient lighting technologies have led to demand increases and, thus, have “led to more overall energy consumption.” Further, they refer to “recent estimates and case studies” that suggest “energy-saving technologies may backfire, meaning that increased energy consumption associated with lower energy costs because of higher efficiency may in fact result in higher energy consumption than there would have been without those technologies.”

First off, yes, it is likely that many efficiency improvements are associated with some rebound effect. It’s been with us forever, and it’s been known for over a century. More efficient lighting leads to people using more light. Key here is “leads to.” Causality matters. More on that in a minute.

For now, a quick look at the actual technology in question. It turns out the technology developments for LED lighting are, in fact, much greater than previous advances in lighting. Figure 1 [see the pdf] shows the dramatic pace of technology change in LED efficacy. The Nobel Prize was well-deserved: LEDs provide a major energy-saving innovation.

But what about the claim that this efficiency improvement will only lead to more energy use? This claim is simply not justified. Noting that lighting dots the globe at night today when it did not in the 19th century may be confounding correlation with causation. The world is also much wealthier today and the service provided by light from electricity is very different than candlelight. Perhaps earlier lighting would have dotted the globe at night in 1850 too had we been as wealthy as today and had consistent lighting. We cannot say without looking at the evidence.

The evidence we have is quite clear. Shellenberger and Nordhaus say “The I.E.A. and I.P.C.C. estimate that the rebound could be over 50 percent globally,” and they then proceed to talk about “backfire,” a rebound effect of over 100 percent. That’s quite a jump from 50 to 100. What’s missing here is that most studies, including the IEA’s and their own(!), take 60% as an upper bound. The IPCC summarizes the evidence as thus:

“A comprehensive review of 500 studies suggests that direct rebounds are likely to be over 10% and could be considerably higher (i.e., 10% less savings than the projected saving from engineering principles). Other reviews have shown larger ranges with Thomas and Azevedo (Thomas and Azevedo, 2013) suggesting between 0 and 60%. For household‐efficiency measures, the majority of studies show rebounds in developed countries in the region of 20-45% (the sum of direct and indirect rebound effects), meaning that efficiency measures achieve 65-80% of their original purposes.”

We have each performed our own detailed surveys of the literature (Azevedo 2014; Thomas & Azevedo, 2013Gillingham et al. 2013; Gillingham et al. 2014) and largely agree with these statements from the I.P.C.C. The bottom-line: the evidence for a “backfire” is weak. The rebound effect is clearly there, but first it’s generally relatively small—especially in developed countries. Perhaps most importantly, where it does exist—and it does—it’s good.

Energy inefficiency can’t be good. That doesn’t yet mean that efficiency alone is sufficient. Every economist worth his or her degree would conclude that we need a price on carbon or a similar instrument. Bonus fact: there’s no direct rebound effect with pricing mechanisms.

As the Nobel Committee notes in its press release: “The LED lamp holds great promise for increasing the quality of life for over 1.5 billion people around the world who lack access to electricity grids.” In short, and as two of us say in a shorter letter to the editor, LEDs alone clearly won’t solve global warming, nor will they solve global poverty. But they are a step in the right direction for both. Thank you, Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura, and to the Nobel Committee for recognizing their work.

Published in full as part of a broader post on "Is There Room for Agreement on the Merits and Limits of Efficient Lighting" by Andrew Revkin on the DotEarth blog of The New York Times. For a shorter take, see our letter to the editor of The New York Times. For a longer take, see "The Rebound Effect and Energy Efficiency Policy."

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What if bees had value?

Episode 5 of Paul G. Allen and Morgan Spurlock’s We The Economy explores the hidden value of natural capital:

A Bee's Invoice from We The Economy, starring Adrian Grenier, Gernot Wagner, Jodi Beggs, and Robert F. Kennedy Jr.

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The Silver Bullet Of Climate Change Policy

From Forbes.com:

By Bob Litterman and Gernot Wagner

Whenever the conversation turns to climate change, someone is sure to opine that there’s no silver bullet. The issue is simply too complex to have one solution. When you focus on all the changes that need to occur to reduce greenhouse gas emissions globally it seems like a multifaceted approach is the only way forward.

Most of the world’s vexing problems share that feature. Mideast peace, nuclear non-proliferation, Eurozone stability, and plenty of other national security problems have no single right plan of attack. Some past plans might have brought us tantalizingly close to a seeming solution, but then reality started interfering once again, reconfirming the complexity of it all.

Climate change must surely be in that category. No single country, no single technology, no single approach can seemingly solve this one for us once and for all. Picking a single technology will almost inevitably end in some form of disappointment. Bureaucrats, the saying goes, ought not to try to pick winners. Leave that to venture capitalists for whom failure is a way of life. For every Apple and Facebook, there are dozens who never make it out of the garage. And clean technology doesn’t yet even have a single Apple and Facebook as the standout approach revolutionizing the field.

It turns out, though, that how you frame the issue is crucial. If you think like an engineer there are dozens of challenges. If you think like an economist, there is one. It’s guiding the ‘invisible hand’. How can you create the appropriate incentive to decrease the pollution that’s causing climate change? For that, the government need not be in the business of picking winners at all. What it should—and can—do is identify the loser that’s been clear for decades: greenhouse gas pollution. And the solution is equally clear: create incentives to reduce emissions by pricing it. If we make this one change, most other actions that are needed will follow.

That’s what the European Union has done by capping carbon emissions from its energy sector, including large industrials, covering almost half of total carbon emissions. That’s what California is doing with over 80 percent of its total global warming emissions. It’s what China is experimenting with in seven city and regional trials, including in Beijing and Shanghai. All these systems put a price on greenhouse gas pollution.

On the other side of the ledger, there are still much larger incentives to consume fossil fuels in many other countries. The International Energy Agency estimates that global subsidies are well over $500 billion. These subsidies, which incentivize emissions, sadly dwarf the paltry incentives to reduce them. Free marketeers, small government advocates, and others who dislike distorting government subsidies should be appalled at the tax money poured into fossil fuels.

There’s one simple principle that’s been around in economics for so long that no economist worth his or her degree would question the conclusion: increase the price, watch the quantity demanded go down. It’s such a universal truism that economists call it the “Law of Demand.” Generations of graduate students have estimated the effects of price on demand for anything from the generic widget to demand for car miles driven. People may be irrational at times, but one thing that we know for sure is that they respond to incentives.

Everything we know from decades of the study of human behavior would lead us to believe that carbon pollution will go down as the price on emissions increases. The only interesting question is by how much.

The prescription then for anyone seriously concerned about climate change is simple: price carbon to the point where its now unpriced damages are incorporated into the price, and get out of the way. It’s simple. It works. It’s conservative to the core.

It’s also a silver bullet solution if there ever was one.

Bob Litterman is a Partner at Kepos Capital, LP. Gernot Wagner is a senior economist at the Environmental Defense Fund.

Posted in Cap and Trade, Politics, Technology| Leave a comment
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