Bioethanol is in the gas most of us put in our cars. This renewable fuel comes from corn, potatoes, and other plants, and reduces the harmful emissions associated with petroleum-based fossil fuels. As a reminder, fossil fuels like coal and oil are also derived from plants, but they are not considered renewable because it takes the Earth thousands of years to convert plant material into these energy-rich forms.
Even though it is considered renewable, ethanol has received a black eye in recent years. That’s largely because it takes so much energy to plant, fertilize, harvest, and distill the product. This is known as the “embedded energy” in biofuels. It takes an equivalent amount of fossil fuel energy to produce the energy contained in bioethanol.
That’s not such a great ratio compared to the biodiesel that comes from oilseed plants like canola or sunflower. In that scenario, every unit of energy expended to create the fuel produces five units to use. That’s because less heat is needed to manufacture biodiesel, compared to bio-ethanol.
There are also concerns about using rich agricultural lands to create fuel instead of food. In fact, many scientists use the term “agro-fuels” instead of biofuels to emphasize this point.
Some states are innovating programs that use marginal lands, such as highway medians and roadsides, to grow canola or sunflowers for biodiesel. Grown on roadsides, biodiesel fuels don’t reduce crop yields and don’t raise the price of food grains in the world market.
This is real home-grown energy for the future.
Web Links
Freeways to Fuel: Center for Agronomic and Woody Biofuels
http://cawb.info/htm/free-ways-to-fuel
Energy Bulletin on Embedded Energy in Ethanol
Photo, taken on September 18, 2006, courtesy of Flickr.