U.S. EPA officials writing rules for implementing the expanded national biofuels mandate said yesterday that they are open to changing methods for measuring biofuels' greenhouse gas emissions and plan to seek outside review of the matter.
But the agency has not bowed to industry pressure to withhold language on a key issue: measuring the emissions from "indirect" land-use changes stemming from increased cultivation of crops used in fuel production.
The 2007 energy law expanded the national renewable fuels standard to 36 billion gallons by 2022 and requires that growing volumes—ultimately reaching 21 billion gallons—come from next-generation biofuels such as cellulosic ethanol.
The rule is being reviewed by the White House Office of Management and Budget.
"We believe we are on track for completion of an expedited review," said Paul Argyropoulos, a senior policy adviser with EPA's Office of Transportation and Air Quality. "Unless there are some really sticky issues that I am not aware of to get the proposal out, I would say that we could see a proposal out in the next month."
Argyropoulos spoke at a meeting of a group that advises EPA on agricultural issues and repeatedly committed the agency to a broad review of input that will follow the rule's issuance.
"We need to emphasize that this is a proposal," he said, noting that in some areas the agency will be "co-proposing" options. "It is an opportunity for everyone to chime in on this thing," he said.
The 2007 energy law created the first federal standards for greenhouse gas emissions from biofuels. "Advanced" biofuels must have at least 50 percent lower emissions than conventional fuels, and cellulosic fuels—which reach 16 billion gallons—must be 60 percent lower.
But measuring the sum of the greenhouse gases relating to the lifecycle of fuels feedstock production and harvesting, refining biofuels and using them is a complex and evolving field.
Vincent Camobreco, another EPA staff member, told the advisory group yesterday that the agency will consult EPA's Science Advisory Board and also seek external peer review on the lifecycle analysis.
In particular, a major controversy erupted last year with the publication of a raft of competing studies on how "indirect" land-use changes affect the emissions levels.
The issue revolves around the extent to which use of land for growing biofuels crops prompts clearing of forests of other land worldwide for food production, thereby releasing substantial amounts of carbon into the atmosphere.