Do biofuel policies seek to cut emissions by cutting food?

March 27, 2015, Princeton University

A study published today in the journal Science found that government biofuel policies rely on reductions in food consumption to generate greenhouse gas savings.

Shrinking the amount of that people and livestock eat decreases the amount of carbon dioxide that they breathe out or excrete as waste. The reduction in food available for consumption, rather than any inherent fuel efficiency, drives the decline in in government models, the researchers found.

"Without reduced , each of the models would estimate that biofuels generate more emissions than gasoline," said Timothy Searchinger, first author on the paper and a research scholar at Princeton University's Woodrow Wilson School of Public and International Affairs and the Program in Science, Technology, and Environmental Policy.

Searchinger's co-authors were Robert Edwards and Declan Mulligan of the Joint Research Center at the European Commission; Ralph Heimlich of the consulting practice Agricultural Conservation Economics; and Richard Plevin of the University of California-Davis.

The study looked at three models used by U.S. and European agencies, and found that all three estimate that some of the crops diverted from food to biofuels are not replaced by planting crops elsewhere. About 20 percent to 50 percent of the net calories diverted to make are not replaced through the planting of additional crops, the study found.

The result is that less food is available, and, according to the study, these missing calories are not simply extras enjoyed in resource-rich countries. Instead, when less food is available, prices go up. "The impacts on food consumption result not from a tailored tax on excess consumption but from broad global price increases that will disproportionately affect some of the world's poor," Searchinger said.

The emissions reductions from switching from gasoline to ethanol have been debated for several years. Automobiles that run on ethanol emit less , but this is offset by the fact that making ethanol from corn or wheat requires energy that is usually derived from traditional -emitting sources, such as natural gas.

Both the models used by the U.S. Environmental Protection Agency and the California Air Resources Board indicate that ethanol made from corn and wheat generates modestly fewer emissions than gasoline. The fact that these lowered emissions come from reductions in food production is buried in the methodology and not explicitly stated, the study found.

The European Commission's model found an even greater reduction in emissions. It includes reductions in both quantity and overall food quality due to the replacement of oils and vegetables by corn and wheat, which are of lesser nutritional value. "Without these reductions in food quantity and quality, the [European] model would estimate that wheat ethanol generates 46% higher emissions than gasoline and corn ethanol 68% higher ," Searching said.

The paper recommends that modelers try to show their results more transparently so that policymakers can decide if they wish to seek greenhouse gas reductions from food reductions. "The key lesson is the trade-offs implicit in the models," Searchinger said.

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dogbert
5 / 5 (1) Mar 27, 2015
The reduction in food available for consumption, rather than any inherent fuel efficiency, drives the decline in carbon dioxide emissions in government models, the researchers found.


The production an use of ethanol has always resulted in much larger carbon production than simply burning fossil fuels.

"Without these reductions in food quantity and quality, the [European] model would estimate that wheat ethanol generates 46% higher emissions than gasoline and corn ethanol 68% higher emissions," Searching said.


But of course, there is no reduction in food consumption because corn or wheat is diverted to produce ethanol. Farmers continue to produce sufficient food and people are not starving from the production of ethanol as is evident from the so called "obesity epidemic".

Ethanol production has never been about carbon reduction. It has always been about redistributing resources.
gkam
1 / 5 (1) Mar 28, 2015
This ethanol mandate was invented by Agribusiness, and pushed through Congress by them, not the eco-freaks. We were well aware of the Food-versus-Fuel controversies, back into the late 1970's.
antigoracle
not rated yet Mar 28, 2015
EAT LESS, PAY MORE.

The AGW Cult, YES, we are your future.
antigoracle
not rated yet Mar 30, 2015
The study looked at three models used by U.S. and European agencies, and found that all three estimate that some of the crops diverted from food to biofuels are not replaced by planting crops elsewhere. About 20 percent to 50 percent of the net calories diverted to make ethanol are not replaced through the planting of additional crops, the study found.

Ah, the "genius" of the AGW Cult; starve the poorest. After all, if you're not breathing then you're not releasing the evil CO2.
gkam
not rated yet Mar 30, 2015
Those with no understanding of how we got here will blame others but the real crooks and perps, Agribusiness and its whores in Congress.
antialias_physorg
not rated yet Mar 30, 2015
Production of bio-ethanol should be restricted to sources like:
- spoiled food/food waste
- non-food parts of plants that are otherwise thrown out (stems, leaves, etc.)
- plants that are grown on lands that otherwise cannot be used for food production
- non-food biomaterial sourced from the oceans.

...and the use of bioethanol should be restricted to balancing the energy grid when other renewables aren't available and as an emergency reserve.

I think under those conditions bio-fuel makes sense. But for widespread use in everyday situations (power generation, mobility, ... ) there are better alternatives.
Dethe
1 / 5 (1) Apr 04, 2015
biofuel policies rely on reductions in food consumption to generate greenhouse gas savings
It has been proven many times, that biofuels actually increase the consumption of classical fossil fuels. If these fuels are still saved, it just means, the production of another commodity must get limited with production of biofuels. But the governmentally subsidized production of biofuels is way too good business for people involved for to "forget" the macroeconomical calculus.
gkam
1 / 5 (1) Apr 04, 2015
Blame Agribusiness, Dethe.

We ecofreaks warned of this decades ago.

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