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Chair's Corner
• • •
July/August 2005
The SUV
in the Pantry
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Tom Starrs |
I spend a fair amount of time thinking about
how to reduce my family’s dependence on energy, particularly
energy derived from fossil fuels. I commute to work by bicycle
or bus, install compact fluorescents when light bulbs burn out,
replace major appliances with the most efficient ones I can afford,
and cast jealous glances at my friends who drive hybrids or alternative-fueled
vehicles. But until recently, I didn’t think of myself as
an energy glutton because of the food I eat.
Then I read an astonishing statistic: It takes about 10 fossil
fuel calories to produce each food calorie in the average American
diet. So if your daily food intake is 2,000 calories, then it
took about 20,000 calories to grow that food and get it to you.
In more familiar units, this means that growing, processing and
delivering the food consumed by a family of four each year requires
the equivalent of almost 34,000 kilowatt-hours of energy, or more
than 930 gallons of gasoline. (For comparison, the average U.S.
household annually consumes about 10,800 kilowatt-hours of electricity,
or about 1,070 gallons of gasoline.) In other words, we use about
as much energy to grow our food as to power our homes or fuel
our cars.
Overall, about 15 percent of U.S. energy use goes to supplying
Americans with food, split roughly equally between the production
of crops and livestock, and food processing and packaging. David
Pimentel, a professor of ecology and agricultural science at Cornell
University, has estimated that if all of humanity ate the way
Americans eat, we would exhaust all known fossil fuel reserves
in just seven years.
The implications of agricultural energy use for the environment
are disturbing. According to the Intergovernmental Panel
on Climate Change, agriculture contributes over 20 percent of
human-caused greenhouse gas emissions, including more than 20
percent of carbon dioxide, 55 percent of methane and 65 percent
of nitrous oxide. In addition, our energy-intensive agriculture
industry contributes substantially to soil erosion, loss of wildlife
habitat, degradation of water quality from chemical runoff and
causes other adverse environmental impacts.
Much of the energy embedded in our food comes from growing grains
that require further processing to be eaten. Producing a 2-pound
box of breakfast cereal, for example, requires the equivalent
of burning half a gallon of gasoline.
Eating high on the food chain is even worse. Eating a carrot or
an apple gives the diner all of the caloric energy in those foods,
but feeding these foods to a pig and then eating the pig reduces
the energy available by a factor of 10. That’s because the
pig uses most of the energy just staying alive, and stores only
a fraction of the energy in the parts that we eat. All told, it
takes 68 calories of fossil fuel to produce one calorie of pork,
and 35 calories of fuel to make one calorie of beef.
Interestingly, the path to reducing the energy intensity
of the food system dovetails nicely with the path to
a healthy and nutritious diet. It can be summarized in three simple
suggestions.
First, eat lower on the food chain. That means more fruits and
vegetables, and fewer meats and fish. Meats, poultry and fish
contain necessary proteins, but most American diets contain too
much protein — about twice the recommended quantity. Since
80 percent of grains go to feeding livestock, the amount of energy
used indirectly to support our diet of double bacon cheeseburgers
— with the secret sauce and supersized, please — is
staggering. And, if you do eat meat, then try to avoid animals
grown in feedlots or factory pens. They take far more energy calories
to raise than free-range, grassfed critters, which have only about
a third of the embedded energy.
Second, eat more fresh foods and fewer processed foods. Fruits
and vegetables again, but also whole grains, legumes and other
less-processed foods, have much less embedded energy. In general,
the more packaging, the more processing — and the more energy
associated with its production.
Third, buy local. Incredibly, the food items on U.S. grocery store
shelves have traveled an average of about 1,500 miles. And some
foods are much worse.
Table grapes grown in Chile, transported by ship to California
and shipped by truck to Iowa have traveled over 7,200 miles. Pineapples
grown in Hawaii, shipped by plane to California and by truck to
Iowa have traveled over 4,200 miles. In response, some agricultural
scientists have proposed ecolabeling programs based on carbon
dioxide emission rankings or broader lifecycle assessment information.
These analyses provide better information than just the miles
traveled. For instance, because they travel by air rather than
by ship, the Hawaiian pineapples are among the most carbon intensive
of foods, contributing about 40 pounds of carbon dioxide per pound
of pineapple. That is about 10 times the next highest figure among
the foods studied.
In my hometown of Portland, Ore., individuals and businesses alike
are starting to recognize and respond to the public’s concerns
about fossil food. Grocery stores featuring locally grown and
organic products are common. Farm stands, farmer’s markets
and community-supported agriculture operations are thriving. Here,
even fast food restaurants are using local and organic ingredients.
For instance, Burgerville is a local chain that buys exclusively
Oregon Country
Beef, the branded product of 40 family ranches in the region that
produce an all-natural product made without hormones, genetically
modified grain or any animal byproducts. Burgerville promotes
the fact that customers can trace the source of their food from
ranch to table — and play a role in sustaining the local
agricultural economy. Another local company, Hot Lips Pizza, worked
with a group of Northwest farmers to create a Food Alliance-certified
local market for organic wheat and flour, providing its customers
with pizza that is more sustainability grown. It is also really,
really tasty.
After all, you are what you eat.
Thomas Starrs |
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