Random Thoughts on Food/Energy Linkages
The idea of corn-based energy system strikes me as wildly irrational. In my first book, Farming for Profit in a Hungry World (1977), and even earlier in an article in Environment, I calculated that took about 10 calories a fossil fuel energy to send a single calorie of food to the dinner table. The ratio for corn-based ethanol is not nearly as unfavorable, and with some new technology could possibly even produce a surplus.
Transportation is a significant contributor to the energy requirements for food production. Food typically travels more than 1500 miles. I give a further explanation of this statistic below. Fuel efficiency is a very relevant consideration here, but consuming local food supplies is probably a simpler method of conserving fuel.
In any case, shifting the energy system to corn-based ethanol increases the price of corn, a plant used for cattle feed and fructose, responsible for a considerable part of obesity in the U.S. By diverting corn to energy production, the supply of corn for food will shrink, perhaps causing a reduction in obesity, but also more likely to increase starvation in poor countries.
The intensive use of energy causes global warming, which is presently causing a heat wave that is threatening the current corn harvest — a very troubling negative feedback link.
Pirog, Rich and Pat Schuh. 2003. The Load Less Traveled: Examining the Potential of Using Food Miles and CO2 Emissions in Ecolabels. Leopold Center for Sustainable Agriculture, Iowa State University.
A food mile is the distance food travels from where it is grown or raised to where it is ultimately purchased by the consumer or end-user. A Weighted Average Source Distance (WASD) can be used to calculate a single distance figure that combines information on the distances from producers to consumers and amount of food product transported. U.S. Department of Agriculture Agricultural Marketing Service produce arrival data from the Chicago, Illinois terminal market were examined for 1981, 1989, and 1998, and a WASD was calculated for arrivals by truck within the continental United States for each year. Produce arriving by truck traveled an average distance of 1,518 miles to reach Chicago in 1998, a 22% increase over the 1,245 miles traveled in 1981.
A WASD was calculated for a sampling of data from three Iowa local food projects where farmers sold to institutional markets such as hospitals, restaurants, and conference centers. The food traveled an average of 44.6 miles to reach its destination, compared with an estimated 1,546 miles if these food items had arrived from conventional national sources.