How to Grow Fuel That's Good for the Planet

Posted: 06-Feb-2006; Updated: 17-Jan-2007

Burning a plant to create fuel adds no net carbon to the atmosphere. The amount released is equal to the amount absorbed during photosynthesis. What tips the balance is the energy used in farming -- for plows and harvesters, for the manufacturing of pesticides and fertilizer -- and in conversion and transportation. Environmental Defense is working to improve land-use and energy-production practices to right that balance. We also want to ensure that farmers can earn money by cutting carbon. Here's how:

Sustainable farming: No-till farming stores carbon in the soil. Cutting back on fertilizers reduces nitrous oxide, a potent greenhouse gas. And leaving just 40% of stalks and leaves in the field renourishes soils.

Ecosystem protection: Ecologically vulnerable lands should not be used for bioenergy crops. Incentives should be increased for planting forests, which provides the greatest emissions reductions per acre and filters air and water.

Efficient conversion: Small scale, widely distributed biorefineries reduce transportation costs and energy use. So does the use of waste products: Lignin, the part of a plant that can't be converted to sugar, can be burned to power the biorefinery; the leftover mash can be fed to livestock.

Choosing the right crop: Making ethanol from corn requires lots of energy and fertilizers, yielding small net reductions in emissions. Bigger gains come from using fast-growing crops like switchgrass. The most immediate gains will come from converting wood chips and other wastes.