Is Ethanol As "Green" As We Think?
By Christopher Patrick
The “green fuel” ethanol is appearing a lot in the news these days. It is possible you’re a little confused by the conflicting stories. Some studies indicate that ethanol is good for the environment; others say that it is bad. Reports argue about the efficiency of production, the effect on the global and local economies, and whether or not it is even green. With all this controversy you might have some trouble making up your mind about whether growing corn for ethanol here in Maryland is a good or a bad thing.
Ethanol is an alcohol made from fermenting sugars; we humans have produced it for consumption (i.e., beer and wine) for thousands of years. We also mix ethanol with gasoline to use as automobile fuel. The percentage of ethanol, made from corn, found in U.S. fuels ranges from 10 percent to 85 percent. This practice is not that new. Ethanol fuel made from sugarcane has been used for decades in Brazil. However, recently ethanol has been touted as a green fuel and American ethanol production using corn has skyrocketed.
Ethanol is considered green because the carbon produced by burning it comes from plants that drew carbon from the atmosphere, unlike fossil fuels, which go directly from the ground to the air and are not recycled again as energy. Ethanol has also been praised for reducing the producer’s dependence on foreign oil. Brazil recently became completely energy self-sufficient by using a combination of ethanol from sugarcane and domestic oil.
The actual energy efficiency of ethanol depends on what it is made from. Making this fuel from plants involves breaking down the plant matter into sugar; this is the challenge. The United States uses corn, which is only about 25 percent as efficient as sugarcane (the source of Brazil’s ethanol) when you factor in the energy it takes to grow corn and convert it to ethanol. The net energy gain is so poor that some scientific studies question whether corn ethanol is worth the effort. Right now corn ethanol is only profitable due to government subsidies. In the future new procedures making “cellulosic ethanol” from wood chips, sawdust, and switchgrass will make ethanol production economically viable; however, this is estimated to be a decade away.
In spite of the controversy corn-based ethanol production is increasing dramatically in response to the Energy Policy Act of 2005. From a global perspective this has positive and negative economic effects. As the purpose of corn production switches from food to ethanol the cost of food corn will increase. Corn feeds beef and cattle; the rising price of corn will increase the prices of red meat, poultry, and eggs until more sustainable practices are developed. According to the Economist magazine, food index prices have increased 75 percent since 2005, affecting the poor around the world. On the flip side corn farmers worldwide will benefit from rising grain prices.
These same global issues come into play here in the Chesapeake Bay watershed. According to the state agricultural statistics survey, in the last year the average market price of corn increased from $2.19 to $3.25 per bushel. A recent U.S. Department of Agriculture study posits that in response Maryland corn acreage increased 10 percent this year, to 540,000 acres. Corn is predicted to increase by another 500,000 acres in the coming years, through a combination of agricultural expansion and farmers switching from crops such as soybeans. From the corn farmer’s perspective this
is great news; however, not all agriculture is going to benefit. At 35 percent poultry is the largest part of Maryland agriculture. Rising prices for eggs and meat caused by rising costs of feed may cause stagnation in the poultry market.
On the environmental side we may be reducing carbon emissions by switching from petroleum to corn ethanol, according to which expert you talk to, but there are also unforeseen side effects. Growing corn requires a great deal more fertilizer than growing other crops. As corn acreage increases the nitrogen runoff into the Chesapeake Bay will also increase. If predictions about corn expansion are correct nitrogen runoff will increase by 8–16 million tons annually, according to estimates from one recent study. That is a lot of extra nitrogen, and it will fuel algal blooms, causing oxygen-less dead zones in the Bay.
There are steps farmers can take to prevent increased runoff into the Bay. Consider contacting your local legislators to let them know you are concerned about this issue and that you’d like safeguards put in place. As new technologies, such as cellulosic ethanol from wood chips and switchgrass, become cost effective, some of these problems will solve themselves because corn will not continue to be used for ethanol production. However, there isn’t enough plant matter on the entire planet to meet our global energy demands even if cellulosic ethanol becomes cheap and effective. Using “green” fuel can help us reduce our global carbon emissions but we still need to conserve and look for alternative energy sources.
Christopher Patrick has a bachelor of science degree from the University of Maryland, College Park, in behavior, evolution, ecology, & systematics, and is currently a graduate student in the Ecology, Evolution, & the Environment Cluster of the Biological Sciences Department at the University of Notre Dame, South Bend, Indiana, studying biotic homogenization and community ecology.