Thinking Clearly about Oil and Alternative Fuels

07/20/2009 03:40 pm ET | Updated May 25, 2011

Never mind the recent decline in oil prices from their record highs. The age of cheap oil is over. And it will not return. Shrinking supplies of conventional crude, rising demand from emerging markets and the shadowy presence of speculators have forever ended the days of $20 per barrel oil and $1 per gallon gasoline. If oil were "only" expensive, it would be painful but not particularly dangerous. But because remaining conventional oil supplies are increasingly located in hostile or unstable countries, our oil addiction is also a huge threat to our national security. We need to think clearly about alternatives to oil.

We are safer as a nation when oil alternatives fit easily into our existing fuel distribution and vehicle system, stretch domestic oil supplies and can be produced in large volumes at reasonable cost. We already have this in the blending of 10 percent ethanol (E10) into more than 70 percent of regular unleaded gasoline sold in this country and in 85 percent ethanol (E85) for the more than 7 million flex-fuel vehicles capable of using higher blends of ethanol on the road today.

About nine billion gallons of ethanol will be produced in the US this year, most of it from corn. That is a fraction of the 140 billion gallons of gasoline America will use, but much larger volumes of "cellulosic ethanol" are on the horizon. Cellulosic materials include agricultural and urban wastes, woody materials and grasses. Call it "grassoline." Corn ethanol and grassoline can help ease our dangerous oil addiction, but we must not be sidetracked by irrelevant issues.

Of all the irrelevant issues concerning ethanol, the so-called "net energy" argument is near the top. According to this argument, ethanol is not a good fuel because "it takes more energy to make ethanol than you get when you burn it in your car." The fact is that all fuels, every single one, take more energy to make than you get when you burn them in your car. Gasoline actually has a worse "net energy" than ethanol. Net energy is simply irrelevant.

From a national security perspective, the most relevant question is, "How much oil does ethanol replace?" The answer might surprise you. Very little oil - mostly diesel fuel for planting, tilling and harvesting crops - is required to produce ethanol. A recent publication in the journal Science shows that only about 0.04 MJ (mega joule, a measure of energy content) of petroleum is required to produce one MJ of ethanol. That is a 25:1 advantage in favor of ethanol production. Because ethanol has less energy per gallon than gasoline, we get more than 30 gallons of ethanol for every gallon of oil we "invest" to make the ethanol, versus eight-tenths of a gallon of gasoline per gallon of oil. When ethanol is used as E85 fuel in a flex-fuel vehicle, we are effectively getting around 800 miles per gallon of oil consumed.

Thus, overall domestic fuel supplies are stretched far into the future when we take our own oil and use it to produce ethanol from our domestic agricultural and forest materials. Ethanol from corn and the much larger amounts of grassoline that are on the way are the only near-term petroleum alternatives we have that significantly enhance national security by replacing lots and lots of oil.

Note: Dr. Dale is set to debate Dr. David Pimentel, professor of ecology and entomology at Cornell University, today (Nov. 18) at Wellesley College regarding the benefits of biofuels.