Growing algae for biofuels is an energy-intensive process that can generate more greenhouse gases than the process sequesters, according to a new study.
Examining the life cycle of algal biofuels, researchers from the University of Virginia found that the process emits high levels of greenhouse gases because algal production requires using large amounts of fertilizer.
Those fertilizers often come from petroleum-based sources, and fertilizers also emit nitrous oxide, a greenhouse gas, according to the study. The study, published in the journal Environmental Science and Technology, said that while biofuel production from crops such as corn, canola, and switchgrass can result in a net carbon dioxide uptake, that is not yet the case with algal biofuels.
The paper said that one promising way to overcome the environmental impact of using fertilizers to grow algal biofuels is to produce them with effluent from sewage treatment plants. Proponents of algal biofuels also said it is too early to make firm conclusions about the environmental impact of the technology because it is still in its infancy.
Article appearing courtesy Yale Environment 360.
photo: Proyecto Agua