Sunday, February 19, 2006

Can Ethanol Replace Oil?

My article “The Problem with Oil” took a look at the nation’s oil balance sheet and illustrated the scope of the problem America is faced with. America imports over half of the crude it uses, the vast majority of which goes to fueling our cars, heating our homes, and keeping our airplanes aloft. Currently, there is an automotive fuel that is relatively renewable, fairly clean, and producible domestically: E85—a blend of 85% ethanol (yes, the stuff of moonshine) with 15% gasoline.

For a variety of reasons, not just any engine can run on E85. Some automobiles are currently sold as “Flexible Fuel Vehicles” that can run on E85, and theoretically any gasoline engine can be converted to run on it; however in reality, conversions can’t be done because there aren’t any EPA certified aftermarket conversion kits. So a conversion is currently illegal, as no aftermarket parts companies want to take the time and expense to get EPA certified. This is a purely legislative hurtle that could be solved in two easy steps: easing the EPA certification process, and setting a target date where all new cars that are sold must be flex-fuel compatible.

I make three key assumptions in this article: that we Americans won’t drive less in the near future, we cannot convert infrastructure for technology that does not exist, and we cannot divert our current agricultural output from present uses to new ones—we can only seek to increase output (in other words, we can’t stop producing food in our quest to produce fuel).

Ethanol is produced from the starches in grains. Ethanol production is well understood and has been with us since before the internal combustion engine—for as long as people have felt the need for a cocktail, they have known how to produce grain alcohols. Currently, the best crop for producing ethanol that can be grown domestically is corn (the ideal crop would be sugarcane, but America’s climate is wrong for it). The question remains: can we grow enough corn to largely replace gasoline?

According to the Department of Agriculture’s National Agricultural Statistics Service (NASS), the approximate total land area of the United States is 2,345,697,640 acres, of which roughly 41.4% is farms. Slightly over half of that land is pastureland or some other non-growing land, with the rest used for a variety of crops—although only about two thirds of that cropland is actively harvested in any given year.

In 2002 (the date of the last NASS atlas), there were 68,230,523 acres of corn harvested for grain. When corn is harvested, it is generally shelled and put into bushels weighing approximately 56 pounds each. The average yield in 2002—a relatively average year—was 129.3 bushels per acre, which converts to roughly 3.28 metric tons of shelled corn per acre.

Depending on the refining process and the quality of the crude, a 42 gallon barrel of crude can yield approximately 19.5 gallons of gasoline and other petroleum products. A metric ton of shelled corn can provide 110 gallons of ethanol—ethanol which can be blended with the gasoline from a single barrel of crude to make about 130 gallons of E85.

Here’s the bad news: America would need 340,936,640 additional acres of corn cultivated to replace all of the US imports of oil—acreage greater than the area cultivated for all crops in any given year. Keeping with the assumption that America cannot divert current crops to large-scale fuel production, we would be faced with having to more than double the amount of land that is currently cultivated. Yet there is a limit to how much land is available for cultivation: cities take up a significant amount of land, national parks take up yet more land, and a great deal of land is simply unsuitable for cultivation of any crop. The cold reality is that we likely cannot dedicate enough land to completely convert to E85.

So is there no point in discussing E85? That’s not necessarily true: America has a refining shortfall of some 3,035,000 barrels per day—requiring us to purchase refined products internationally. With a mere 50,787,411 additional acres of corn we could replace our need to purchase refined products internationally without building any new refineries.

America needs to face up to its oil addiction, and sooner is much better that later. For the foreseeable future there is no single fix for the problem. Yet E85 derived from corn could help to be a stop-gap measure as America begins to wean itself off of oil, and it’s something that can be started on immediately. The technology exists, what is needed is the political and corporate leadership.


Sources of information:
Corn to ethanol conversion data.
Information about E85.
Agricultural statistics.

4 Comments:

Blogger stickman said...

Excellent post!

I am currently driving a flex-fuel vehicle. I mainly drive it on gasoline, but when I travel I get E85 when I can. I purchased E85 for 6 cents less than reg unleaded in Statesville, North Carolina last week. I typically get about 90% of the mileage I get with gasoline, it varies.

If I can buy E85 in Statesville, NC (with delivery charges from Iowa) for $2.11 per gallon, then even with a 51 cent per gallon subsidy, this stuff is getting close to being competitive with oil. For me this erases all the arguments about it requiring more energy to produce than it can deliver, because aside from research grants, ethanol gets no other subsidy. I think this stuff would be a wise investment.

9:56 AM  
Blogger Seth said...

Thanks for reading, I'm glad you enjoyed it. Sadly, we probably can't grow enough corn for every tank in America...but we certainly can do more than we do now. I think that it's a good first step towards a more secure, cleaner, domestic fuel supply.

7:19 PM  
Blogger stickman said...

The argument that we don't have enough land to rely totally on ethanol seems valid to me, at this time. I say "at this time" because not a week has gone by lately that I don't see some innovation, be it in genetic engineering of feed stock for ethanol, or finding that we can derive ethanol from other sources, such as rice stalks. Once the profit motive sets in, America's engineers have proven their ability to make the possible probable, and quickly.

All that said, if enough people buy these flex-fuelers over the next couple of years, then ethanol will serve to write OPEC's obituary, and that's no small matter. The demand will bring the delivery infrastructure to every area, and we ff'ers will be able to opt out of the hydrocarbon merry-go-round. It is just a matter of time.

2:53 PM  
Blogger Seth said...

Yes, there is some hope that there are better crops/distilling methods which will yield more ethanol with less feedstock. Switchgrass and custom engineered enzymes are supposedly an area with promise...but I put that into the category of "future tech". I've got nothing against future tech, but don't want to wait for it!

1:54 PM  

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