Tuesday, October 04, 2016

Ethanol in U.S. Gas Tanks Is Backfiring for Climate Change

Despite accelerating global warming, federal rules require that gasoline contain ethanol made from corn. (Credit: Katy Warner/flickr) Click to Enlarge.
A team of researchers has concluded that for every three gallons of corn ethanol that’s being burned under America’s flagship renewable fuel rules, Americans will avoid burning just one gallon of gasoline made from crude.

Their findings add to evidence that the mandated use of biofuels under the Renewable Fuel Standard, which was approved by Congress and is overseen by the EPA, is making the problem of global warming worse — while doing little to ease fuel imports.

The researchers, from the University of Minnesota, St. Paul, focused their analysis on the “fuel rebound effect.”  That’s economist jargon describing an unintended market consequence of rules requiring America’s gasoline industry to blend biofuels into its products.

“The fuel rebound effect is so strong, and the climate benefits of the biofuels are so small, especially for corn ethanol, that emissions increase,” said Jason Hill, an energy and sustainability researcher who led the work, published in the journal Energy Policy. “That’s a big problem.”

When lawmakers approved the Renewable Fuel Standard in 2005 and tweaked it in 2007, it was assumed that biofuels by now would be coming from agricultural waste and other woody material.  But the technology needed to do that remains unviable.  About 10 percent of gasoline sold in the U.S. this year will come from growing corn and other crops — 15 billion gallons of ethanol overall.

By driving up the supply of alternative fuels, the standard has caused demand for fossil fuels to drop.  But not on a gallon-for-gallon basis.

Biofuels contain less energy than fossil fuels, so more must be burned to travel the same number of miles.  And increasing the production of an alternative fuel helps make fossil fuels cheaper, tempering the reductions in fossil fuel demand — the so-called fuel rebound effect.

After surveying more than a dozen peer-reviewed studies, the researchers assigned a broadly accepted numerical value to the fuel rebound effect.  They also compared the energy content of biofuel with gasoline.  Finally, for the sake of number-crunching, they assumed that overly optimistic EPA assumptions about the climate benefits of different biofuels were accurate.

Crunching those numbers led the the researchers to conclude in their paper that America’s fuel standard “actually leads to a net increase” in greenhouse gas emissions — by hundreds of millions of tons from 2006 to 2022.
The EPA treats heat-trapping carbon dioxide pouring from exhaust pipes from biofuels as though it doesn’t exist.  That’s based on what scientists have called a “critical climate accounting error,” which is also rife in Europe and elsewhere, in which bioenergy is treated as a “carbon neutral” fuel despite its direct and indirect roles in polluting the atmosphere.

Read more at Ethanol in U.S. Gas Tanks Is Backfiring for Climate Change

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