Dueling studies highlight focus on climate impacts of renewable fuel standard

Source: Tiffany Stecker and Julia Pyper, E&E reporters • Posted: Tuesday, June 3, 2014

A couple of industry- and environmentalist-led studies on the greenhouse gas impact of the federal renewable fuel standard are shining a light on the biofuel policy’s role in affecting climate change.
The RFS, which calls on the United States to boost biofuels production to 36 billion gallons per year by 2022, has been used as an argument for jobs, for low-priced gasoline and for national security. But recently, parties on both sides of the biofuels debate have been redirecting the focus onto climate change. The Environmental Working Group released a study last week that found U.S. EPA’s proposed cut in the amount of ethanol would prevent 3 million tons of carbon dioxide from entering the atmosphere — the equivalent of 580,000 cars.In March, biotechnology trade group BIO published a study with the opposite message.Proposed cuts in the RFS would increase net emissions by 6.6 million metric tons between 2013 and 2014. EPA proposed in November to lower the 2014 mandate for corn ethanol by nearly 10 percent and the mandate for advanced biofuels by 41 percent from the agency’s 2010 projections. This marks the first time EPA has suggested scaling back the RFS gallon amounts.”Usually, when people disagree so widely, they have very different assumptions,” said Mark Bunger, research director at Lux Research, a technology research and advisory firm. In this case, both groups have taken different approaches to measuring greenhouse gas emissions from biofuels.BIO based its findings on the GREET model developed by scientists at the Argonne National Laboratory, as well as EPA’s own estimates. In the latest version of the model, the scientists estimate that the rise in Canadian oil sands imports have increased the carbon intensity of transportation fuel and thus decreased the relative carbon intensity of biofuels.

The Environmental Working Group used a different system. Its researchers took EPA’s Regulatory Impact Analysis from 2010, which estimates that digging up of wetlands and grasslands to grow corn for ethanol will lead to a net increase of greenhouse gas emissions. On top of that, it adjusts EPA’s assumption that ethanol companies will use plant biomass to power their refineries. Today, the fuel of choice for ethanol facilities is low-cost natural gas, not biomass, said Scott Faber, Environmental Working Group’s vice president of government affairs.

Combat with ‘different yardsticks’

BIO’s analysis “relies upon a model that includes significant flaws that have been recognized by the developers of the model,” said Faber. The model doesn’t accurately account for the limits of growing corn — notably, water — as demand driven by the RFS increases.

But Environmental Working Group’s comparison between petroleum and ethanol emissions is incongruous, said Paul Winters, communications director for BIO.

The Environmental Working Group “has selected the [GREET model] estimate for oil and compared it to their own estimate of the emissions of corn ethanol, using different boundaries,” wrote Winters in an email. “Their assertion that corn ethanol’s emissions are higher than oil’s emissions isn’t proven, because they’re essentially using different yardsticks to measure.”

It’s been a big year for climate change. The U.N. Intergovernmental Panel on Climate Change released three reports between last September and April on the physical causes, impacts and mitigation possibilities for climate change. Earlier this month, the U.S. Global Change Research Council published the National Climate Assessment. And today, the Obama administration will unveil sweeping carbon regulations for the nation’s power plants.

The IPCC reports were generally supportive of biofuels as a mitigation strategy, saying that bioenergy plays a “critical role” in reducing carbon emissions. But the authors did bring up some concerns over biofuels’ effects on water resources, biodiversity and human communities (ClimateWire, April 14).

Although there are still questions on how to assess biofuel emissions in the real world, a lot of the scientific logic has been established, said Bunger. Conclusions on the benefits and drawbacks depend on what assumptions are made, and what kind of measurements are taken.

EPA’s decision to propose a cut in the number of gallons of corn and Brazilian sugar-cane ethanol was largely based on concerns around the blend wall. This is the situation in which there is more ethanol in the market than there is room in the national fuel supply, assuming that ethanol can only safely be blended in gasoline at a rate of 10 percent. The petroleum industry says that incorporating a greater amount could damage engines, although EPA has approved blends as high as 15 percent.

The dirtier oil argument

This focus on the blend wall, not climate, was apparent in meetings with EPA, said Sen. Amy Klobuchar (D-Minn.) earlier this year.

“They were not making environmental arguments about why the rule had been changed,” said Klobuchar, a strong supporter of the RFS.

At its inception, the RFS was not established to do something about climate change but as a reaction to spiking oil prices and a war in Iraq.

“The Energy Independence and Security Act did not pass 86 to 8 because the majority of the Senate wanted to do something about climate,” said John DeCicco, a research professor at the University of Michigan Energy Institute, referring to the 2007 law that codified the RFS. “It passed because of waving the flag and rah-rah energy independence.”

According to DiCicco, who supports the Environmental Working Group’s assessment that corn ethanol increases carbon emissions, many environmental groups saw the RFS as “green” and threw their support behind it.

Although environmental support for corn ethanol has waned since the passage of the act, there’s still a climate argument to be made for the RFS, said Jeremy Martin, a senior scientist in the Clean Vehicles Program at the Union of Concerned Scientists.

“With oil getting dirtier each year, the current turmoil facing the RFS is certainly no victory for climate action,” said Martin. “Corn ethanol is not going away, regardless of what happens with the RFS, so [the Environmental Working Group’s] focus on short-term corn-ethanol volumes is misdirected.”