Reconsidering bioenergy

Accelerated restoration in progress at the Malheur National Forest, Oregon  [photo: U.S. Forest Service] 

Protecting the Earth's climate takes on greater urgency every day. The vast majority of carbon dioxide (CO2) and other climate-wrecking greenhouse gas (GHG) emissions comes from the unmitigated use of fossil fuels. But that doesn't mean that every form of alternative energy is helpful for the planet. Case in point: bioenergy, such as liquid biofuels to replace oil or forest products to replace coal.

Indeed, using biomass for energy at large scales does not belong on the short list of actions to take for climate protection. This is the conclusion of a commentary by Bill Schlesinger and myself just published in the Proceedings of the National Academy of Sciences. Given the real-world limitations of not only technology but also land-use governance, we argue that the priority policymakers have given to promoting bioenergy is profoundly misplaced.

Breaking down biofuels analysis

Debates about the merits of biofuels have gone on for at least a generation. Over time, one might think that the accumulation of data would resolve key issues, especially those about biofuels and global warming. Nevertheless, the arguments not only persist but have become even more heated.

What has taken things to a new level of contention is that some researchers (myself included) are now rethinking the heart of the matter, namely, the belief that biofuels are inherently carbon neutral. This is the assumption that the CO2 emitted when biofuels are burned does not lead to a net increase in emissions because the carbon in the biofuel is recycled during feedstock growth. My new paper, "Methodological issues regarding biofuels and carbon uptake" published in the journal Sustainability, breaks this aspect of the debate down to its bare essentials.

Biofuels vs. Biodiversity and the Need to Think Beyond Carbon Neutral

Seminar given at the University of Michigan, Thursday, February 8, 2018, as part of the 2016-2018 "Beyond Carbon Neutral" seminar series.

Download the presentation slides [PDF]

ABSTRACT

Just over a decade ago, policymakers gave a big boost to biofuels through the Renewable Fuel Standard (RFS) and similar policies. These policies included sustainability provisions for protecting sensitive lands; the intent was to spur the production of advanced biofuels that would be sustainable in many ways including low CO2 emissions. Now, new studies appear each year revealing the destruction of diverse habitats as biofuel production amplifies the global demand for land. There have also been multiple bankruptcies of highly-subsidized advanced biofuel operations. What went wrong and how can we find a better path forward?

Carbon taxes and the affordability of gasoline

Although new taxes can seem like a third rail in American politics, taxing carbon seems to be an approach that is slowly gaining ground in public discussions of ways to tackle global warming.

We recently explored what a carbon tax would mean for how U.S. consumers feel about the affordability of gasoline. It turns out that for over 90% of Americans, a $40 per ton carbon tax -- which translates to an extra 36 cents per gallon -- would still leave them a gasoline price range that they consider affordable.

Of course, consumers' views on the issue depend on their household incomes, with lower income households expressing a lower price threshold for "pain at the pump," so to speak.

Further details on these survey findings can be found in the article on "A carbon tax: how much would be too much?" at the University of Michigan Energy Survey website, where the full report is also posted.

A new and deeper wrinkle in the biofuel debate

Two short articles just published by the journal Climatic Change highlight the divide in scientific thinking about the effect of biofuels on CO2 emissions. A commentary by Robb De Kleine and colleagues at Ford Motor Company criticizes a paper on the topic published last year by myself and colleagues at the University of Michigan. My response to their commentary explains why I believe that our approach is correct, in contrast to the established lifecycle analysis method that our critics say is the best way to address the question.

Cropland adjoining patches of forest. All arable land
removes carbon from the atmosphere at varying rates. 

This quarrel reflects a new stage in the long-running debate because it does not involve disputes about net energy use or even the food-versus-fuel and land-use change issues raised over the past decade. It is instead a disagreement about the core assumptions to use when examining the question, particularly whether or not biofuels should be treated as inherently carbon neutral. That's the assumption that the CO2 emitted when biofuels are burned does not count because it is biogenic, i.e., newly removed from the atmosphere when feedstocks are grown. My work challenges this assumption, showing that it only holds under certain conditions. De Kleine and colleagues defend the assumption, arguing that it is true unconditionally.

The disagreement is not merely academic. Because new oil production technologies have expanded the supply of economically attractive fossil-based liquid fuels, the business case for biofuels rests increasingly on their value for mitigating CO2 emissions. The stakes are high for both the biofuels industry and for policies to address global warming.

Biofuel Research vs. Mandates: House Science Committee Hearing

John DeCicco speaking before the U.S. House of Representatives Committee on Science, Space and Technology, where the Subcommittees on the Environment and on Energy held a joint hearing entitled "Examining Advancements in Biofuels: Balancing Federal Research and Market Innovation" on Tuesday, July 25, 2017. What follows is the statement delivered at the hearing. 

I wish to thank the chairs, ranking members and other members of the Committee and Subcommittees for the opportunity to testify.

The question being addressed today, that of the right balance between fundamental scientific research and government intervention in the marketplace, is crucially important. The focus on biofuels is telling because it involves so many aspects of the question. Indeed, federal biofuels policy provides a morality tale of how things go wrong when the right balance is not maintained.

Before delving into the problems, however, I want to emphasize the importance of maintaining a robust federal investment in research across all fields of study. Funding for science is crucial to maintain American leadership and foster the innovation that leads to high-quality job growth. Federal support for university research is especially crucial for training a new generation of Americans who can fill those jobs. 

A to-the-point radio interview on biofuels and climate

As a guest yesterday on the WEMU (89.1 FM from Eastern Michigan University) "Issues of the Environment" segment, I answered host David Fair's questions about how our recent work differed from the established lifecycle analysis methods used to analyze the greenhouse gas emissions impacts of biofuels.

The resulting interview has great questions from David and clear explanations from myself about why the results of government modeling of the issue are misleading and why, as far as climate is concerned, it's better to repeal biofuel policies and focus on reforestation and other ways to remove carbon from the air and sequester it on land.

Morning Edition: Issues of the Environment 

U-M Researcher Calls For End To Current Biofuel Policy In The U.S.

http://wemu.org/post/issues-environment-u-m-researcher-calls-end-current-biofuel-policy-us

By DAVID FAIR • WEDS 01 FEB 2017

In August of 2016,  University of Michigan Energy Institute scientists, led by John DeCicco, released an 8-year study.  It estimated powering an American vehicle with ethanol made from corn increased carbon pollution more than using gasoline.  In this week's "Issues of the Environment,” David Fair talks with Professor DeCicco about the findings and what it means to future policy. 

IMAGE CREDIT: DREW FROM ZHRODAGUE / FLICKR.COM

Listen Here [10:09 mp3 link] 

The need to speed up carbon uptake

Last week I gave a talk, entitled "Net Ecosystem Production and Actionable Negative Emissions Strategies," at the American Geophysical Union (AGU) fall meeting in San Francisco. It was presented in a session on negative emissions strategies, which refers to the topic of removing CO2 from the air in order to slow -- and hopefully one day reverse -- the buildup of carbon in the atmosphere.

Net ecosystem production (NEP) is the net rate at which carbon is taken up by a terrestrial ecosystem. It determines the amount of carbon that becomes available for some use (e.g., crop or timber harvest) or for sequestration on the land. Scientifically speaking, any parcel of land with living organisms on it is an "ecosystem," including farm land or managed forests as well as natural lands and parts of the built environment that aren't totally paved with sterile concrete.

Plants and other organisms that carry out photosynthesis in the terrestrial biosphere actively remove CO2 from the air. Thus, they provide a fundamental mechanism for pursuing negative emissions. However, to be meaningful for climate mitigation -- which is the sense in which the term negative emissions is used -- carbon must be removed from the air more quickly than it is already being removed. That's what "the need to speed up carbon uptake" means and for the terrestrial biosphere, that means increasing NEP.

The fact that terrestrial carbon management is an actionable ("here-and-now") strategy and that using it for negative emissions requires increasing NEP are the main points of my talk. It can be download here in PDF format including both the narrative and slide images.

Tailpipes top smokestacks as nation's largest CO2 emitters

Transportation, which runs almost entirely on petroleum fuels, and electricity generation, which had used mainly coal, have long been the largest sources of CO₂ emissions in the United States. Although power plant smokestacks exceeded motor vehicle tailpipes and other mobile sources such as aircraft in terms of CO₂ emissions for nearly forty years, this year brings a crossover of these two emission trends. The CO₂ emitted by the transportation sector has been greater than that from the power sector for seven of the past eight months, and so 2016 is on track to see mobility overtake electricity as the country's biggest contribution to global warming.

Latest tweak to U.S. biofuel mandate is politically correct and ecologically cruel

EPA's new Renewable Fuel Standard (RFS) proposal modestly increases the amount of biofuel that America's cars and trucks have to consume next year but still keeps the total renewable fuel mandate below the Congressionally scripted target.

In the plan released on May 18, ordinary corn ethanol gets a 300 million gallon boost, biodiesel is bumped up by 100 million gallons and other so-called advanced biofuels see a 200 million gallon increase compared to last year's regulation. Nevertheless, the proposed 18.8 billion gallon total remains significantly lower than the 24 billion gallon goal for renewable fuel in 2017 that Congress wrote into law back in 2007.

EPA's approach reflects a compromise worked out last year after several tortuous years of regulatory delay. This "politically correct" strategy has the agency taking a middle road that balances the money-making interests of the biofuel industry and the corn and soybean lobbies against the engineering and economic realities that render ethanol and biodiesel such inferior motor fuels. Reactions to the proposal were predictable. The renewable fuel lobby and its allies complain "that's not enough" while the oil industry and other critics say "that's too much" biofuel.

House Oversight Testimony on the RFS

This post is a transcript of my oral testimony at the U.S. House of Representatives as delivered on March 16, 2016. 

I wish to thank the Chairs, Ranking Members and other members of the committee and subcommittees for inviting me to today’s hearing.

My name is John DeCicco and I am a research professor at the University of Michigan Energy Institute. My main focus is transportation fuel use and its environmental impact. I hold a doctorate in engineering from Princeton University and have worked on America's energy challenges for nearly 40 years, including 21 years at environmental organizations before returning to academia in 2009.

My recent research has included scientifically rigorous evaluations of the Renewable Fuel Standard (RFS) and other policies that promote biofuels such as ethanol and biodiesel. RFS proponents claim that the policy reduces CO2 emissions. I have found that it does not. In fact, from its inception, the RFS has increased rather than decreased the amount of CO2 entering the atmosphere compared to petroleum fuels such as gasoline.

Think Progress and Out-of-Touch 'Persuasion'

There's no doubt that shifting political opinion toward effective climate action is going to take a lot of persuasion, especially of individuals and policymakers who don't already believe in the urgent need to drastically limit greenhouse gas emissions, or at least tend to rate the environment high on their list of concerns. 

But advocates trapped in the mental boxes of green-group group-think -- and that includes the dear former California governator, Republican though he may be -- are unlikely to change the minds of those in the most need of persuasion by approaching the issue as touted in this recent piece, "Did The Governator Just Come Up With A Republican-Proof Argument On Climate Change?" on Think Progress. 

The question that Mr. Schwarzenegger posed on Facebook was along the lines of "What room with a sealed door would you be rather trapped in, one with a gasoline car running at full throttle or one with an electric car running flat out?" (on treadmills, we presume).

Testimony on the RFS

Here's my statement at today's House hearing on the RFS; see links at the end to access the written testimony and related videos. 

My research shows that the Renewable Fuel Standard, or RFS, has been harmful to the environment from its inception. Now, ten years after the 2005 Energy Policy Act, the program has resulted in higher CO2 emissions than would have occurred otherwise. It also harms the environment in other ways. Sadly, the adverse impacts of the RFS have grown worse since it was expanded by Energy Independence and Security Act (EISA) of 2007.

The notion that renewable fuels readily reduce CO2 is based on a scientifically incorrect understanding of carbon neutrality. Only under certain conditions does substituting a biofuel for a fossil fuel neutralize the CO2 leaving the tailpipe. For that to occur, harvesting the feedstock must significantly increase how rapidly cropland absorbs CO2 from the atmosphere on a net basis. That condition is not met for the corn ethanol mandated by the RFS. It might be satisfied for cellulosic feedstocks, but once properly evaluated, the gains may not be as great as advocates assume.

Thinking Beyond Carbon Neutral

Global climate change is a defining challenge of the 21st century and efforts to address it have many dimensions. Reducing greenhouse gas (GHG) emissions through higher energy efficiency, using solar, wind and nuclear energy, deploying carbon capture and storage (CCS), reducing deforestation, reducing methane emissions and minimizing other causes of excessive radiative forcing are all important. No one option will suffice and it is crucial to integrate technology solutions with policy drivers.

Because the carbon dioxide (CO2) emitted by fossil fuel use is the largest source of anthropogenic GHG emissions, the climate challenge is often characterized as the need to "decarbonize" the economy by eliminating fossil fuels. However, carbon is literally the fuel of life; the natural carbon cycle annually circulates twenty times as much carbon as released from fossil fuels and the majority is biogenic carbon fixed through photosynthesis. Although rapid release of fossil carbon is the primary cause of rising atmospheric CO2 concentrations, the real problem is an imbalance in the carbon cycle rather than fossil fuel use per se. Thus, the real need is to bring the carbon cycle into balance and eventually restore a global net carbon sink.

The mistaken modeling behind biofuel boosters' emissions claims

Arguments about the pros and cons of biofuels such as ethanol have gone on for many years. The latest debates pertain to whether proposals to limit the ramp-up of the Renewable Fuel Standard (RFS) would result in higher or lower emissions of carbon dioxide (CO2) and other climate-disrupting greenhouse gases.

This week Environmental Protective Agency (EPA ) Administrator Gina McCarthy tweeted the benefits of biofuels: 

and signaled the agency's intent to further raise the RFS volumetric mandate: 

At the crux of the issue is the ability to determine the “carbon footprint” of biofuels using computer models. These models, such as the GREET model developed by Argonne National Laboratory in Illinois, use what are known as lifecycle assessment techniques that claim to account for all of the emissions associated with producing and using a fuel. GREET modeling is the basis for assertions by BIO (the Biotechnology Industry Organization) that the RFS has reduced carbon emissions since it was passed in 2005. It is also the basis for the recent University of Illinois statement that the proposed RFS limits would increase CO2 emissions as much as putting nearly one million more cars on the road. 

Bringing biofuels back to earth

After all that's been written about the pros and cons of biofuels over the years, it's fair to ask whether there's anything left to say. It turns out that there is, and a new insight comes from evaluating what actually happens on the earth, that is, on the land where the plants used to make biofuels are grown.

When do biofuels really balance carbon?

The belief that biofuels are inherently carbon neutral rests on an assumption that the CO₂ absorbed when their feedstocks are grown balances out the CO₂ emitted when the fuel is burned. That's why it's said that biofuels recycle carbon, in contrast to fossil fuels' one-way flow of carbon into the atmosphere.

However, the extent to which CO₂ emissions actually get balanced needs to be verified, not just assumed, even as obvious as it may seem. A careful analysis shows that biofuel carbon flows balance out only under certain conditions. Moreover, those conditions are at best only partly met for the biofuels now being used. To see why, it is necessary to understand some fundamental concepts about CO₂ flows between the biosphere and atmosphere.

Scrutinizing the logic on biofuels

This post picks up a thread based on comments that Prof. Robert Brown and Prof. Bruce Dale made on my "Don't pitch low-carbon fuel ..." post. Both Robert and Bruce take strong exception to my analysis. They invoke the commonly made assumption that substituting a biofuel for a fossil fuel reduces net CO₂ emissions because biofuel use recycles carbon while fossil fuel use does not.

This widely used view of the biofuel lifecycle does not tell
the whole story.  [Image credit: www.EthanolRFA.org] 

Their argument is based on the following logic:

(1) Fossil fuels send old carbon on a one-way trip to the atmosphere, thereby increasing the amount of CO₂ in the atmosphere.

(2) Biofuels use carbon recently taken from the air that is then released back to the air, resulting in no net change in the amount of CO₂ in the atmosphere.

(3) Therefore, substituting a biofuel for a fossil fuel reduces the rate of CO₂ buildup in the atmosphere.

Although this basic analysis neglects processing emissions, we can leave those aside for the purpose of this discussion. They are not what's at the heart of the disagreement, and in any case processing emissions do get tracked by lifecycle models, e.g., as used in the RFS and LCFS. 

Don't tout low-carbon fuel; track real carbon instead

My recent studies expose the fallacies behind California's Low-Carbon Fuel Standard (LCFS) and similar provisions of the U.S. Renewable Fuel Standard (RFS). Such policies claim to reduce the carbon footprint of motor fuels, but are more likely to actually increase CO2 emissions.

I'm not alone in expressing such concerns. A paper whose authors include the original developer of the lifecycle analysis method that underpins the LCFS points out how such approaches can mislead policy makers. A recent World Resources Institute (WRI) report faults policies that promote biofuels and create an adverse "food vs. fuel" trade-off.

Among the objections to my criticism is that it is merely academic and fails to offer a constructive solution for the transportation fuel-related CO2 emissions that remain after improving vehicle efficiency and limiting travel demand.

Governor Arnold Schwarzenegger signing AB 32 on Sept. 27, 2006
(Source: Getty Images via Zimbio)

In California, however, the answer is right under policy makers' noses. The Global Warming Solutions Act [Assembly Bill (AB) 32] caps carbon emissions statewide, and starting this year also places transportation fuels under the cap. AB 32 is the best climate protection program established anywhere to date, and with a technical correction plus expanded provisions for carbon offsets, it would be an ideal policy for addressing fuel-related CO2 emissions.

Flawed studies underpin low-carbon fuel policies

Nearly all of the studies used to promote biofuels as climate-friendly alternatives to petroleum fuels are flawed and need to be redone. This conclusion is just one of the findings of my advanced review paper, "The Liquid Carbon Challenge: Evolving Views on Transportation Fuels and Climate," recently published online by Wiley Interdisciplinary Reviews: Energy and Environment. The unhappy assessment is based on an in-depth review of the literature published on the topic over the past two decades.

Once the erroneous carbon accounting methods are corrected, the results will show that policies used to promote biofuels -- such as the U.S. Renewable Fuel Standard (RFS) and California's Low-Carbon Fuel Standard (LCFS) -- actually worsen the buildup of CO₂ in the atmosphere rather than reducing emissions as promised.