Time to rethink misguided policies that promote biofuels to protect climate

September 24, 2013

Policymakers need to rethink the idea of promoting biofuels to protect the climate because the methods used to justify such policies are inherently flawed, according to a University of Michigan energy researcher.

In a new paper published online in the journal Climatic Change, John DeCicco takes on the widespread but scientifically simplistic that biofuels such as ethanol are inherently "carbon neutral," meaning that the heat-trapping emitted when the fuels are burned is fully balanced by the uptake that occurs as the plants grow.

That view is misguided because the plants used to make biofuels—including corn, soybeans and —are already pulling carbon dioxide out of the atmosphere through , said DeCicco, a research professor at the U-M Energy Institute and a professor of practice at the School of Natural Resources and Environment.

DeCicco's paper is unique because it methodically deconstructs the life-cycle-analysis approach that forms a basis for current promoting biofuels. Instead, he presents a rigorous analysis based on biogeochemical fundamentals to identify conditions under which biofuels might have a climatic benefit. These conditions are much more limited than has been presumed.

"Plants used to make biofuels do not remove any additional carbon dioxide just because they are used to make fuel as opposed to, say, corn flakes," DeCicco said.

DeCicco stressed that research and development are important to create better options for the future. R&D is especially needed for bio-based or other technologies able to efficiently capture and use more carbon dioxide than is already being captured and stored by natural vegetation. But going beyond R&D and into subsidies, mandates and other programs to prop up biofuels is unwarranted, he said.

DeCicco's direct carbon accounting examines carbon sources and sinks (storage sites, such as forests or crop fields) separately, an approach that lends greater clarity about options for addressing carbon dioxide emissions from liquid fuels.

"Biofuels have no benefit at the tailpipe," DeCicco said.

Per unit energy, the carbon dioxide emissions from burning ethanol are just 2 percent lower than those from gasoline. Biodiesel yields carbon dioxide emissions about 1 percent greater than those from petroleum diesel.

"If there is any climate benefit to biofuels, it occurs only if harvesting the source crops causes a greater net removal of carbon dioxide from the air than would otherwise have occurred," DeCicco said.

His paper concludes that for now, it makes more sense to enable plants to soak up carbon dioxide through reforestation and to redouble efforts to protect forests, rather than producing and promoting biofuels.

Corn ethanol production of 14 billion gallons supplied 4.4 percent of total U.S. transportation liquid fuel use in 2011. However, even that small share of liquid fuel supply required 45 percent of the U.S. corn crop.

Biofuels are the presumed replacement for the petroleum-based transportation fuels, gasoline and diesel, that dominate liquid fuel use. In the United States, the federal Renewable Fuel Standard mandates a large increase in biofuels use, which has now reached 16 billion gallons a year, mainly . But DeCicco pointed out that a recent National Academy of Sciences report concluded that the Renewable Fuel Standard may not reduce greenhouse gas emissions at all, once global impacts are counted.

Explore further: Alternative-fuel cars are no carbon cure-all

More information: dx.doi.org/10.1007/s10584-013-0927-9

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1.9 / 5 (9) Sep 24, 2013
Since it seems we are stuck with alcohol in the gas I wish companies that make small engines would use rubber gaskets and parts that are immune to the alcohol. I'm tired of having to buy new carburetors for my stuff with small engines. The alcohol melts the rubber and it clogs up all the ports in the carburetors. As far as I can tell you can't get it back out either. I've tried.
1.6 / 5 (13) Sep 24, 2013
We're not stuck with it; we just need to vote the politicians who are responsible for it out of office. When that finally happens, in addition to reducing fuel-system issues, we'll no longer have fuel crops competing with food crops, and the rate of inflation for those consumer items will slow down. Fuel mileage numbers for gasoline-powered vehicles will increase enough to make real-world difference.

Until then, the best answer for small engines that see seasonal use is to just use non-ethanol fuel. If you're in the US or the GWN, take a look here- http://pure-gas.org/

A lot of the these retailers will sell gas in 1 or 5 gallon containers.
1.5 / 5 (8) Sep 24, 2013
I keep trying to vote them out. Unfortunately as far as I can tell the average person living in a city seems to think food comes from a grocery store. Most of them have no idea what getting food to a store actually requires or where it comes from and if they don't find what they want in one they just go to another. A food shortage would leave them totally lost.

We have a couple of stations in town that does sell pure gas but they are all on the other side of town on roads that I won't ride a bike on which is my main transportation. This area is not very bike friendly. Taking a cab would put me paying about $60+ for 5 gallons of gas. I've already switched out a couple of engines on my stuff to electric motors. That has mostly solved the problem for me.

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