Exploring Algae as Fuel.
The New York Times, July 26, 2010.
"SAN DIEGO - In a laboratory (at Sapphire Energy) where almost all the test
tubes look green, the tools of modern biotechnology are being applied to
lowly pond scum.
Foreign genes are being spliced into algae and native genes are being
Different strains of algae are pitted against one another in
survival-of-the-fittest contests in an effort to accelerate the evolution of
fast-growing, hardy strains.
The goal is nothing less than to create superalgae, highly efficient at
converting sunlight and carbon dioxide into lipids and oils that can be sent
to a refinery and made into diesel or jet fuel.
Dozens of companies, as well as many academic laboratories, are pursuing the
same goal - to produce algae as a source of, literally, green energy. And
many of them are using genetic engineering or other biological techniques,
like chemically induced mutations, to improve how algae functions.
Algae are attracting attention because the strains can potentially produce
10 or more times more fuel per acre than the corn used to make ethanol or
the soybeans used to make biodiesel. Moreover, algae might be grown on arid
land and brackish water, so that fuel production would not compete with food
production. And algae are voracious consumers of carbon dioxide, potentially
helping to keep some of this greenhouse gas from contributing to global
But efforts to genetically engineer algae, which usually means to splice in
genes from other organisms, worry some experts because algae play a vital
role in the environment. The single-celled photosynthetic organisms produce
much of the oxygen on earth and are the base of the marine food chain.
At a meeting this month of President Obama's new bioethics commission,
Allison A. Snow, an ecologist at Ohio State University, testified that a
"worst-case hypothetical scenario" would be that algae engineered to be
extremely hardy might escape into the environment, displace other species
and cause algal overgrowths that deprive waters of oxygen, killing fish.
Many scientists, particularly those in the algae business, say the fears are
overblown. Just as food crops cannot thrive without a farmer to nourish them
and fend off pests, algae modified to be energy crops would be uncompetitive
against wild algae if they were to escape, and even inside their own ponds.
Some companies are sticking with searching for and breeding natural strains.
"Re-engineering algae seems driven more by patent law and investor desire
for protection than any real requirement," said Stan Barnes, chief executive
of Bioalgene, which is one of those companies.
Sapphire Energy, which is three years old, has raised $100 million from
prominent investors, including Bill Gates. Sapphire is also getting $100
million in federal financing to build a demonstration project containing 300
acres of open ponds in the New Mexico desert.
The company has inserted a gene into algae that allows the organisms to make
a hydrocarbon they would not naturally produce, one that would help make
fuel. The company is also developing algae that can thrive in extremely
salty and exceedingly alkaline water. It has even developed algae resistant
to the herbicide Roundup. That would allow the herbicide to be sprayed on a
pond to kill invading wild algae while leaving the fuel-producing strain
Not all these traits are being developed by genetic engineering, because in
many cases scientists do not know what genes to use. Instead, the company
screens thousands of strains each day, looking for organisms with the right
properties. Those desirable traits can be further enhanced by breeding or
In one room at Sapphire's lab, parallel tubes contain algae with identical
traits growing under identical conditions. But each strain is slightly
different, and only the fastest growing one - determined by which tube turns
the darkest green - will be chosen for further development.
Algae can reproduce rapidly, doubling in as little as a few hours. And they
can be carried long distances by the wind. "They have the potential to blow
all over the world," said Richard Sayre of the Donald Danforth Plant Science
Center in St. Louis.
Instead of using open ponds, some companies are using bioreactors, which
typically contain the algae in tubes. Some experts say, however, that these
would not totally prevent escapes. "The idea that you can contain these
things and have a large-scale system is not credible," said John R.
Benemann, an industry consultant in Walnut Creek, Calif. He said, however,
that he saw absolutely no risk from genetically engineered algae.
Sapphire says it is not growing any genetically engineered algae in open
ponds yet. When it is ready, it says, it will comply with all regulations.
Genetically engineered algae, whether in open ponds or enclosed bioreactors,
are likely to be regulated by the Environmental Protection Agency, which now
regulates genetically engineered microbes under the Toxic Substances Control
Steven G. Chalk, acting deputy assistant secretary for renewable energy at
the Energy Department, said any federally financed project, like Sapphire's
New Mexico demonstration, would have to undergo an environmental assessment.
But risks would be assessed case by case, he said, not for all conceivable
genetically modified algae."
Dr. Ann C. Wilkie Tel: (352)392-8699
Soil and Water Science Department Fax: (352)392-7008
University of Florida-IFAS
P.O. Box 110960 E-mail: [log in to unmask]
Gainesville, FL 32611-0960
Campus location: Environmental Microbiology Laboratory (Bldg. 246).
BioEnergy and Sustainable Technology Society