Kerry's Biofuels Initiative

Friends: As part of his energy plan Kerry wants to establish a $20B "Energy Security and Trust Fund" capitalized from federal off-shore oil and gas leases. This trust fund is intended to:
1. Provide assistance in strengthening fuel efficiency of automobiles by helping auto plants retool to build more efficient advanced technology vehicles (hybrid and advanced clean diesel technology) and to provide tax credits to consumers to jump start the market for such vehicles.
2. Create a "Clean Fuels Partnership" that will propel America toward producing 20% of its motor fuel from biomass (ethanol from corn; biodiesel from soybean oil; and fuel from other agricultural wastes) by 2020 (15 years). By 2012 (7 years) gasoline sellers will be required to include an increasing percentage of renewable fuels from corn, soybeans, agricultural residues and other biomass to ensure a minimum of 5 billion gallons (presumably of some combination of ethanol and biodiesel) per year. He wants to accelerate the production of advanced biodiesel and cellulosic ethanol and other clean fuels. Some of these funds will be used for tax incentives to make such fuels competitive economically.

MY comment: Where is this ethanol and biodiesel going to come from? How much of our agricultural production would need to be devoted to the generation of these biofuels? I have been looking up some numbers and doing a few back-of-the-envelope calculations for those interested enough to read on: if not please delete.
1. Ethanol
In 2003 (BP statistical review -2004) the US consumed 142 billion gallons of gasoline and another nearly 40 billion gallons of petroleum-based diesel for transportation. According to websites promoting fuel ethanol, in 2001 about 615 million bushels (about 6% of the 10 billion bushel harvest) of corn was used to produce about 2 billion gallons of ethanol (so we can produce about 3.25 gallons of ethanol/bushel of corn).
To increase the ethanol production from 2 billion to 4 billion gallons per year we would need to increase the fraction of the corn devoted to ethanol production by 100% to about 12% of the annual crop. Since the energy return over energy invested (EROEI) for ethanol production using traditional petroleum inputs is at best about 1.25 to 1, this 4 billion gallons of ethanol would replace about 0.8 billion gallons of petroleum gasoline or less than 0.6% of annual petroleum usage.
Suppose we wanted to try to replace all traditional petroleum gasoline with a 10% ethanol-90% gasoline gasohol blend. Then to produce 142 billion gallons of E-10 gasohol we would need 14.2 billion gallons of ethanol. This would require about 4.4 billion bushels of corn or about 44% of the 10 billion bushel corn crop. In other words, a little less than half the acreage now devoted to corn production would have to be directed to fuel production.
So in this way we would displace 14.2 billion gallons of gasoline with ethanol (roughly speaking - a gallon of ethanol contains less energy than a gallon of gasoline). Once again, using traditional agricultural inputs, the EROEI is about 1.25/1, so the net savings is only about 2.8 billion gallons of gasoline if all of the gasoline we sold were sold as an E-10 blend. So this would correspond only about a 2% savings in total gasoline usage.
Biodiesel
The way to produce 100% biodiesel is by transesterification of a vegetable oil (usually soybean oil in the US) using a base catalyzed reaction of the oil with methanol. According to numbers I have found, about 1.5 gallons of biodiesel can be produced from each bushel of soybeans. The biodiesel produced in this way is a 100% mixture of fatty acid methyl esters (for the chemists among you) that is then blended with #2 petroleum diesel to produce a marketable fuel that is 2% biodiesel and 98% petroleum diesel blend in the most common formulation (other mixtures are possible). The total US petroleum diesel usage for transportation in 2003 was nearly 40 billion gallons. If all of this were to be replaced with 2% biodiesel we would need to generate about 800 million gallons (0.02 x 40e9) of 100% biodiesel each year for blending. This would require about 533 million (800/1.5) bushels of soybeans. The US production of soybeans in 2003 was about 2.45 billion bushels. So a little more than 20% of the soybean crop would need to be devoted to produce biodiesel. I have not been able to find any paper discussing the EROEI for biodiesel production from soy oil. However, given that soybeans are also produced using petroleum inputs, the EROEI is likely not large. Moreover, the methanol that is used also needs to be produced and probably also uses some petroleum inputs. If the EROEI for biodiesel were as high as 2/1, we would save about 400 million gallons (800/2) of diesel fuel this way * about 1% of annual use.

I have no idea whether or not we can afford to devote nearly one half or even 12% of our corn acreage to ethanol production nor whether 20% of our soybean acreage should be devoted biodiesel production. I am not suggesting here that biofuels can not be part of our energy future. But let no one be fooled into thinking that this strategy can be a significant replacement for traditional petroleum-based fuels if we rely on traditional petroleum inputs for the production of the biological raw materials needed for biofuels production. Our political leaders should pay attention to such numbers. Using traditional agricultural inputs, Kerry's biofuels initiative will make a minuscule impact on our energy security. Of course, I don't think that Bush's energy policy does any better in this regard.
ken piers

Ken Piers

"Everything should be as simple as possible - but not simpler." A. Einstein