“When I use a word,” Humpty Dumpty said, in a rather scornful tone, “it means just what I choose it to mean – neither more nor less.”
“The question is,“ said Alice, “whether you can make words mean so many different things.”
“The question is,” said Humpty Dumpty, “which is to be the master – that’s all.”
Humpty Dumpty is alive and well, living in Washington, and prospering as a public relations consultant to renewable fuels producers.
Humpty’s creativity with language was indispensable in fashioning the Renewable Fuel Standard (RFS) in the Energy Independence and Security Act of 2007 (an extension of the original RFS in the 2005 Energy Act). The 2007 RFS requires that U.S. transportation fuels contain annually increasing volumes of "renewable fuels", reaching 36 billion gallons per year (bgy) by 2022. The act defines a renewable fuel to be “fuel. . .produced from renewable biomass and. . .used. . .in a transportation fuel.” Of the 36 bgy, the Act specifies that up to 15 bgy may be corn ethanol and that at least 21 bgy be “advanced bio-fuel” – bio-diesel, bio-gas, and (primarily) ethanol produced from raw material other than corn (“cellulosic ethanol”).
At first glance, this seems an eminently reasonable definition, but what is "renewable biomass?”
The U.S. Energy Information Administration defines renewable energy resources to be “. . .energy resources that are naturally replenishing [italics added] but flow-limited [italics added]. They are virtually inexhaustible in duration but limited in the amount of energy available per unit of time. Renewable energy resources include biomass, hydro, geothermal, solar, wind, ocean thermal, wave action, and tidal action.”
In turn, biomass is plant material, vegetation, or agricultural waste used as a fuel or energy source or as a feedstock in the production of a renewable fuel.
Biomass is fundamentally different from the other energy resources in EIA’s definition. Biomass is naturally replenishing only if it is not produced by on-purpose cultivation, but entirely through natural processes (yielding materials such as animal manure or wood slash and brush, used as domestic fuels in developing countries, or non-food plants, such as trees and switchgrass). Biomass is not naturally replenishing if – like corn, for example – it is produced on purpose through industrial agriculture, as practiced in the U.S., or other forms of intensive cultivation. On-purpose biomass is not renewable.
Biomass produced on purpose, such as through industrial agriculture, is not renewable, because its on-purpose production consumes non-renewable resources – mainly fossil fuels and fertile soil. These non-renewable resources are indispensable to the production of on-purpose biomass and the fuels produced from it. The non-renewable resources are required in part to relax the flow limitation inherent in natural replenishing processes and thereby achieve practical (i.e., economic) yields of biomass per unit of land dedicated to its production.
So, are the renewable fuels called for by the RFS in fact renewable? In particular, is corn ethanol (for which the mandate volume reaches 15 bgy by 2015) a renewable fuel?
Corn ethanol production in the U.S. consumes fossil fuels equivalent, on average, to about 85% of the energy content of the ethanol. Without extensive use of fossil fuels – which are non-renewable – corn ethanol production as practiced in the U.S. would be impossible.
Corn ethanol production is a complex, resource-intensive, and geographically dispersed industrial process that transforms various combinations of natural gas, coal, diesel fuel, gasoline, sunlight, soil, and water into a transportation fuel. In this sense, corn ethanol is analogous to transportation fuel produced from natural gas or coal, via commercial gas-to-liquids (GTL) and coal-to-liquids (CTL) processes. It is not analogous to fuel that might be produced from truly renewable (naturally replenishing) energy resources – wind, solar, hydro, geothermal, etc.
No matter what Humpty Dumpty's way with words enabled the U.S. Congress to say, corn ethanol is not a “renewable fuel.” Nor is bio-diesel, and for the same reasons. Nor is any other bio-fuel produced from an on-purpose biomass source. Calling them renewable does not make them renewable. But it does make them popular.
Would the American public support national ethanol mandates if Humpty hadn't had the genius to apply the word "renewable" to bio-fuels? One can't be sure. But it's no accident that the country's biggest ethanol lobby (one of HD's best clients) calls itself the Renewable Fuels Association.