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Philpott and I discuss biofuels

Nathanael Greene

Posted April 4, 2008

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Two weeks ago, I wrote about some misguided claims by David Pimentel and what I saw as overly broad and overly pessimistic views on biofuels from cellulosic biomass by Tom Philpott. Last week, Tom paid my blog here a visit and posed some reasonable questions and invited folks to what will hopefully be an informative debate on his blog on Grist. So let's have at it.

Rather than start with our points of disagreement, I'd like to start with some points that I hope that Tom and many of our readers will agree with because in the end these points are the reasons that I and NRDC continue to struggle with biofuels despite all the challenges and controversies. First and foremost, we need to stop global warming by stabilizing atmospheric GHG concentrations at the equivalent of less than 450 ppm CO2. For us here in the US, this means reducing our GHG pollution by 80% below 1990 levels by 2050. Furthermore, we have to do this in a way that ensures that the cure is not worse than the disease. In other words, we have to try to stop global warming while also addressing our other major environmental and social challenges and we can't afford to exacerbate those challenges.

This is a daunting challenge and our current path is not going to get us there. We cannot extrapolate forward our current rates of consumption and our current rates of technological improvement and expect to get to a sustainable future. We need important technological innovations and changes to our policies. What's more, there is no single technological innovation that will magically put us on a path to sustainability. We need innovations and changes across our economy.

The good news is that even analysts as conservative and mainstream as McKinsey and Co. believe we can be on the right path by 2030 at little or no cost to our economy as long as we start now. However, it takes aggressive action and requires a wide array of technologies.


1 Constant 2007 dollars

2 Billions of tons of CO2 equivalent eliminated per year relative to business as usual projections

Source: NRDC analysis partially extrapolated from McKinsey report; see

And this is probably even more true in the transportation sector as it is in the rest of the economy. Our current path domestically and internationally is wildly unsustainable with demand growing  and efficiency deteriorating (until our recent victory on increasing CAFE). As a result, gasoline demand is expected to roughly double in the US by 2050 under BAU.

Up to here, I'm hoping that we're all mostly in agreement.

Our options to bend the GHG emissions curve associated with transportation are fairly straight forward: improve the efficiency of our vehicles, change our mode of transport to more efficient ones, travel less, and put lower carbon fuels into our cars, trucks, planes and other forms of transport. When we look at trying to reduce the transportation sector's emissions by 80% from 1990 levels by 2050 through these options, it's not easy to make the numbers add up. In the light-duty vehicle sector, one of the most aggressive scenarios that we have analyzed relies on improving our vehicle fuel economy three fold, cutting our VMT 20% and ramping up the use of electricity to where it drives 50% of all VMT. (For modeling purposes, we assume all vehicles are flex-fuel plug-ins hybrids that use electricity for 50% of their driving and E85 for the rest. To be clear, we don't care if it's this configuration of vehicles and we certainly don't care what fuel molecule ends up being used.) Even under this scenario we still see the need for about 60 billion gallons (on an ethanol basis) of truly low-carbon biofuels (e.g. about an 80% reduction from gasoline lifecycle GHG emissions) to provide about 9 1.4 gigatonnes of CO2 equivalent GHG emission reductions. And even after that, the transportation sector is just barely carrying its weight in terms of providing emissions reductions.


(Note: 38 billion gallons on a gasoline equivalent basis equals 58 billion gallons on an ethanol basis because of the lower energy density of ethanol.)

What happens if these emissions reductions don't materialize from biofuels? Nothing, if we can get them from some other part of the transportation sector, but of course every other option faces technical and political challenges as well. Whether it is battery technologies, entrenched interests addicted to sprawl, or the challenges to rapidly scaling up renewable power and the associated transmission, no pathway is a technically and politically sure thing.

So what if these emission reductions don't materialize from the transportation sector at all?  Again, nothing as long as we get it from some other sector, but again there are challenges everywhere we look. The bottom line is that we need lots of solutions and we need them all to provide as much pollution reduction as they can in a broadly sustainable way.

And that is why NRDC continues to struggle with biofuels. Not because I like ethanol or we like controversial and complicated issues, but because we're committed to stopping catastrophic climate change. To do that we can't afford to give up trying to figure out how to make potentially significant solutions work. 

I'm going to leave off at this point and see if we're in agreement on the premise that we have to struggle hard to figure out how to make potentially significant solutions to the climate challenge work. There are perfectly valid questions about whether biofuels can technically and politically be made to be a solution (and I look forward to discussing them), but I want to make sure that we come to these questions with a shared sense of urgency around trying. We cannot afford blind optimism, but we must share a belief that we can and must over come enough of the technical and political challenges to the solutions to global warming to save our environment from ourselves. 

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john schneiderApr 4 2008 11:40 PM

It's a start NG

Just like we tried with Vinod Khosla, we can try to convince you to abandon ethanol in favor of plugin hybrids, plugged into a renewable smart grid. You do mention plugin hybrids but only give them a possible savings figure of 50%.
The thing is that if a plugin covers the average daily trip length between charging opportunities(about 21 miles I believe), and most do go 40 to 60 miles on plugin power alone, then the liquid fuel savings are more like 80 or even 90%.

As battery technology gets better that range can be 100 miles or more, then the savings goes up over 90%. With those kinds of reductions oil will last for a few decades. And GHG reductions will cure the climate disaster.

This would be set to kick in over a couple of decades, of course no total solution will happen overnight. Cellulosic ethanol would take years to roll out too, according to recent studies.

In 15 or 20 years as batteries approach the energy density of liquid fuel (even 1/5 the density would be equal to liquid fuel burned at 14% in a gas guzzling internal combustion engine, since electric motors are 5 times that efficent), and charge tmes drop to 5 to 10 minutes, no liquid fuel will be needed.

Any molecule that serves as liquid fuel will do, that's true enough, but it has to actually be carbon neutral to be part of the solution to gHG disaster. Ethanol from cellulose, sugar cane, or corn is not carbon neutral. Sorry.

Join us and come on in for the big win Nathanial. And bring NRDC with you. Plugin hybrids plugged into a renewable smart grid is the way to go.

Ron SteenblikApr 5 2008 06:58 AM

Very constructive, Nathanael. I think this post puts the discussion on the right track. Let me add a few additional thoughts on areas for possible agreement:

-- Policies can have large unintended consequences. We know the problem: greenhouse gas emissions (and other pollutants). We should be very, very cautious in acting on the assumption that we know what is the "solution", however. This year's "solution" can turn out next year to be a disaster.

-- The food-versus-fuel debate is not, and should not be, just about the United States and whether the diversion of grains and oilseeds for biofuel production adds 3 cents or 10 cents to the cost of a box of Corn Flakes. In the developing world, where incomes are a fraction of those in the developed world, food often accounts for more than 50% of household expenditure. And most of that expenditure is on unprocessed or semi-processed staples, not highly processed breakfast foods. Double the wholesale price of the primary commodity, and you increase costs for a product like cornmeal -- a staple in southern Africa -- by 40-80%, not 3%. According to this article (not the most authoritative, I realize, but all I could find quickly), "Prices of white corn meal in South Africa have risen by 186% in the last two years, due to poor harvests throughout much of southern Africa and the demand-driven world price, which has been pushed higher by the demand for ethanol produced by corn in the U.S. The number of people the U.N. calls “food insecure,” particularly in Zimbabwe, Swaziland, Lesotho and southern Mozambique, has gone from 3.1 million in 2006 to 6.1 million [in 2007]." Clearly biofuels should not bear all the blame for high grain and oilseed prices, but it offends me when some biofuel enthusiasts (e.g., Prof. Bruce Dale) continue to talk only about the price of corn when prices for other grains displaced by corn are also rising, and to ignore the much bigger impacts these price rises are having on the poor in the rest of the world.

-- We should resist being influenced by the optimism in particular technologies being expressed by those with a financial stake in those same technologies. It is natural, and healthy, that they should be optimistic. But policy-making should be concerned with removing obstacles to people realizing their dreams, not fulfilling those dreams for them.

-- Policies differ in the degree to which they can become entrenched, thereby making a change of course -- as may need to be the case as new evidence of their effects comes to light -- more and more difficult. Government support for R&D is the least distorting. If a particular technology looks fruitless, the government can simply stop funding new projects, and walk away. Government support for poduction is the most distorting, especially (as is bound to happen with any policy touching agriculture) if it generates rents that then become capitalized into the value of production factors. That is exactly what is happening in support for biofuels: owners of scarce factors of production, in this case arable land, are seeing the value of their properties zooming skyward. In Iowa, for example, average land values for farmland have more than doubled since 2000, and approached $4,000 per acre in 2007. Good for owners of farmland; less good for farmers who have to rent farmland, or aspiring young farmers who have not been lucky enough to inherit farmland from their parents. In theory, at least, the main federal-level policy supporting the blending of biofuels in the United States, the volumetric tax credits, are time-bound. Congress could choose to not renew them. (In practice, of course, Congress has renewed them again and again.) Use or blending mandates are the least flexible, and least transparent mechanism for supporting the industry. They are the least transparent because the shift the risk of high production costs to consumers, but give them no choice but to pay that cost. And they are the least flexible because, once in place, a mandate is like a government guarantee. Can you imagine Congress announcing that the mandated volumes for 2022 will drop to zero in 2023?

Critics of current biofuel policies should not automatically be labeled as ignorant, or shills for the oil industry. Unfortunately, it is the nature of policy debates that those who have a vested interest in a particular government action have a head start on their critics. Nobody in academia or the NGO community is going to invest time and intellectual capital thinking about a policy until it starts to take flesh. Marshaling counter-arguments takes time.

I'll stop here, but hope to add some more comments later.

David AhlportApr 5 2008 04:09 PM

I don't really see why the McKinsey study is relevant.

What the study says is:
"We set the cost of biofuels at zero, on the assumption that by 2050 biofuels supply will likely be setting the international price for transportation fuels."

So basically it's assumed that oil will be so expensive by 2050, that we already would have switched to biofuels by then.

So marginal cost and marginal benefit is zero, but only because it represents doing nothing different after 2050, after the switch had occurred.

How is that relevant to the actual cost of implementing biofuels in the first place?


Thats like describing the cost of a solar panel as zero, because the initial capital cost for some reason doesn't exist.

Nathanael GreeneApr 7 2008 06:03 PM

(Note 4.8.08: wrote this comment yesterday in a meeting, typing too fast -- realized today that I'd made a bunch of typing errors ... Here’s is a corrected version.
— Nathanael)

John, Ron, and David,

Thanks for your comments. You’ll get no argument from me on the idea that electrification of transportation has a critical role to play or that electrification should get more attention given the uncertainty around the scale of the potential contribution of truly low-carbon, broadly sustainable biofuels. Where we differ is over the notion that we can afford to abandon one option for the other or that we have to. We need to bring an array of solutions to bear on global warming; there is no magic bullet.

That’s where the McKinsey study is relevant -- not in service of an argument that biofuels will be cheap, but in making the case that if we successfully push the broad package of lots of solutions, stopping global warming as a whole doesn’t need to come at any significant cost.

For these reasons and for many of the points that Ron raises, our top priority policy goal regarding transportation energy (for transportation overall, efficiency is the top priority) is the low-carbon fuel standard. As I’ve discussed before, the LCFS focuses on performance and encourages competition among any technology options that on a full lifecycle basis lower GHG emissions compared to gasoline or diesel.

(P.S. I don’t believe that I have ever claimed, and I certainly don’t maintain, that biofuels are carbon neutral. The biomass part has the potential to create a carbon cycle, which can be carbon negative if the crops are grown very carefully, but in most cases will not be negative.)

(P.P.S. The McKinsey study starts from the assumption that oil will cost $60/barrel — the study does not assume that oil is so expensive that biofuels will obviously be cheaper.)

Russ FinleyApr 9 2008 06:14 PM

The biofuel issue has shifted in just a few short years to the point that all hope now seems to be pinned on fuels not proven economically or environmentally viable. I try not to invest much time discussing the probabilities of future technological breakthroughs. So, even though this all started with a discussion of cellulosic, which I remain agnostic about, the issue of government mandates and subsidies (other than research money) remains contentious.

You mention the need for an 80% reduction four times. Coincidentally, that is the same percentage I tout when I tell people how much one family in particular has managed to reduce gas consumption over the last two years.

The sacrifice this family endured will bring tears to your eyes. They traded one midsize, five-person hatchback for a different one that gets twice the mileage (a 100% improvement) and replaced single occupant trips in their SUV with a hybrid electric bike that has a 15-mile range and can do 30 mph for short bursts. They still have the SUV, but they rarely drive it.

No sacrifice needed. Not only are they saving a lot of money on gasoline but their quality of life has improved. They traded one Seattle progressive favorite, the forest-green Subaru, for another one, the ubiquitous Pious (no typo). And the electric bike means that they longer have to sit trapped in Seattle traffic, vie or pay for parking spaces when making single occupant trips. It happens to be my family but that is irrelevant. It could be any family. I use this example as a real world, on the ground example of how attainable that 80% reduction in personal transport emissions is without biofuel mandates and subsidies.

Pardon all of the links back to Grist. I'm not trying to drive traffic over there. I'm just familiar with my posts and they help to make these points.

I've noticed that a lot of organizations that were not particularly skeptical of the old science that buoyed their support of biofuel mandates in the past are suddenly expressing a lot of skepticism of the new science (which is nothing more than a continuation and improvement of previous research) that does not support biofuel mandates.

john schneiderApr 11 2008 02:55 AM

"The biomass part has the potential to create a carbon cycle, which can be carbon negative if the crops are grown very carefully"

This just isn't possible. The carbon cycle is photosynthesis biochemically trapping the carbon from CO2 as cellulose. the cellulose then is turned into soil. The cellulose very slowly breaks down over years and years.

Burning the cellulose as fuel breaks the cycle. I realize that the carbon cycle neutrality view of fuel farming is a widespread belief Nathanael, it is at the base of every argument for biofuels. But it is fallacious.

We have to halt this mass delusion. Recent studies proving ethanol from corn releases twice the GHG of gasoline have to be accepted.

Biogas digestion of farm waste and selected biomass that would otherwise burn in wildfires uses the carbon cycle to eliminate a huge GHG effect from manure and fertilizer run off.

That is a GHG free biofuel. Especially when the biogas is used in solid oxide fuel cell/turbines at 70% efficiency to backup a ditributed renewable smart grid. Biogas can be stored for low wind or solar times.

Please try to get NRDC around to this POV derived from the latest studies of biofuel carbon emission. Farm biogas, solar, and wind boosted with subsidy diversion is an energy/farm policy we can all get behind.

Get Barack behind it and we could really save our climate. There is not a lot of time top waste on fuel farming boondoggle. The ice in glaciers and ice caps is melting very much faster than the IPCC predicted.

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