Sustainability

West Chester University

 

Biofuels

There is great interest in getting agriculture involved in fuel production. Several different methods exist to convert biomass into fuels. The National Renewable Energy Laboratory (NREL) has a large biomass program. Biofuels can give farmers new streams of revenues. Biofuels have the potential to produce energy with lower greenhouse gas emissions than fossil fuels. However, if they are produced from crops that are used as foodstuff or feedstock, they can drive up the cost of food. If they are produced by using fertilizer or energy intensive steps such as distillation, then they consume as much energy in their production as we get back from burning them. Therefore, there are lots of scientific projects to create more efficient pathways to biofuels.

Biodiesel is formed by adding methanol to fats and oils using sodium hydroxide (NaOH) as a catalyst. New methods of production are being developed. In particular, it would be interesting to find methods that do not produce glycerin as a byproduct or that use caustic NaOH as a catalyst.

Biodiesel clearly has an energy advantage (more energy out than required to produce it). It can also be produced from waste products such as used deep fryer fat; hence, its production can facilitate turning a waste product into something valuable.

A great deal discussion surrounds bioethanol. When produced from sugar cane (as done in Brazil, where the waste biomass is burned to provide the energy for distillation and the resulting charcoal is used as fertilizer rather than using fertilizer that requires natural gas for its production) more energy is derived from burning the ethanol than is used to produce it. When produced from corn (as done in the USA, where ammonia produced from nitrogen and natural gas or coal is used as fertilizer, conventional electricity is used to heat the distillation aparatus and the biomass is thrown away), the energy balance is negative or only slightly positive.

Other alcohols are also being considered for bioproduction. One of these is butanol.Other plants and parts of plants are also being considered for production of alcohols. If we could get alcohols from agricultural and timber wastes - in particular, from cellulose - there could be great potential for biomass to produce inexpensive fuels. Cellulose is a material that is contained in the stringy bits of plants - the parts that humans and animals don't eat - such as corn stalks and cobs.

The Bioenergy Feedstock Information Network (BFIN) is a gateway to a wealth of biomass feedstock information resources from the U.S. Department of Energy, Oak Ridge National Laboratory, Idaho National Laboratory, National Renewable Energy Laboratory, and other research organizations.