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Wednesday, November 28, 2012

Yet Another Type of Biofuel

Creating energy from vegetable mass is a great idea, as long as it doesn't wind up competing with the ever-increasing demand for food, as I have mentioned before. Researchers at the University of California, San Diego, have just reported on their research (in the journal Algal Research) suggesting that ocean algae can be grown as efficiently as freshwater algae for the purpose of creating biofuels. This means that not only does this source of biofuel no compete with food, but it also does not compete for the use of freshwater, which is an increasingly contested resource. The San Diego Union-Tribune has the story:
The scientists genetically engineered marine algae to make valuable industrial enzymes in addition to oil. This feat had been performed in freshwater algae but not in marine species, said UC San Diego researcher Stephen Mayfield, who led the study.
They experimented on a species of algae named Dunaliella tertiolecta, which has a high oil content. They inserted five genes, allowing production of five kinds of industrial enzymes.
“What we showed is that we could do the genetic engineering that’s going to be required to really get costs down,” Mayfield said.Algal biofuels must compete not only against fossil fuels but against other crops, including corn and nonfood “cellulosic” plant material for ethanol, and the jatropha bush, which produces oily seeds. All of these biofuels face limitations that prevent their large-scale adoption anytime soon.
The latter is key, of course, but it is obvious that the sooner we start planning for the use of these sustainable sources of fuel, the better off we'll be.

1 comment:

  1. Thanks to Greg Weeks for linking me to this story:

    Indeed, hydrogen has been discussed for a long time as a source of energy for cars. The problem? Infrastructure, or lack thereof.