|
The Boston
Globe - November 3, 2008
From
a strange brew, cheaper fuel
That
is goal as company tries to simplify ethanol production via bioengineering
The Boston Globe
What does it take
to brew a tank of biofuel?
At the Mascoma Corp.
lab, the recipe might include a dash of enzymes from termite guts, elephant
stomach mixed with yeast, a load of pulverized switch grass or paper sludge,
and a few days of fermentation.
Anything goes here,
as scientists try to find a quicker, cheaper way to make cellulosic ethanol,
a "second generation" biofuel that uses non-food plant residue
and other waste as its main ingredients, instead of corn or soy.
The key is splicing
together the right combination of genes, such as those found in termites
or an elephant stomach, to create a super bug capable of producing cellulose-digesting
and sugar-fermenting enzymes that will help to streamline the brewing
process from four steps to one.
"Don't ask, 'How
did you get something that used to be in an elephant stomach?' "
joked Bruce Jamerson, Mascoma's chief executive and a member of Massachusetts'
Advanced Biofuels Task Force, which was created by the state last November.
Jamerson's company,
which has corporate offices in Boston, recently partnered with General
Motors Corp. to help further its scientists' work at the research facility
in Lebanon, which has 66 employees.
"I'd like to
be [test] driving some vehicles by the end of this year with our product,"
Jamerson said.
If successful, Mascoma's
biofuel could be a locally produced substitute for gasoline made out of
petroleum, as well as for gas alternatives made from food crops. Such
"first generation" biofuels have come under fire because crops
that once fed people were being used to make fuel, possibly driving up
food costs, and producing more greenhouse gases than first thought.
Environmentalists
say Mascoma's biofuel looks promising because it has the potential to
be both affordable and sustainable.
"One of the big
things [they're doing] is making it possible to use a lot of different
materials like grasses or wood chips," said Jeremy Martin, a senior
scientist with the Union of Concerned Scientists, a nonprofit group in
Cambridge.
And it appears Mascoma
is asking questions that Martin said early biofuel makers often did not
ponder, such as, "Where do those [materials] come from and what's
the impact of getting them?"
But commercial production
of an environmentally friendly, cost-competitive biofuel like the one
Mascoma is developing is still years away, according to the state task
force. It estimates that by 2025, the biofuels industry could add up to
$1 billion a year to the Massachusetts economy and create up to 4,000
jobs. Challenges include getting production and fuel-distribution facilities
running and making vehicles powered by biofuels more available.
For now, Mascoma researchers
in Lebanon are still trying to hit upon the right ingredients for their
biofuel recipe, which is likely to include a strain of the microbe Thermoanaerobacterium
saccharolyticum, or T. sacch.
Jamerson said his
company's ethanol-making process takes less time than the traditional
four-step process, which calls for the addition of costly enzymes that
range in price from 50 cents to $1 or more for every gallon of fuel produced.
On a recent afternoon,
bottles filled with samples of microbes lined the shelves in the "organism
discovery" room of the Mascoma lab. It's here that microbes, some
of which were found in hot springs at Yellowstone National Park, are tested
in an oxygen-free chamber to see what they do.
"Just because
they grow in a hot spring doesn't mean they're going to grow in a plant,"
said Larry Feinberg, a research scientist.
In the "molecular
biology" room, which is permeated with the odor of yeast, scientists
splice together genes to develop microbes with specific properties, trying
to find the right combination. The cultures - which look like little dots
of cake frosting - are grown in petri dishes. Later, they are transferred
to shaking flasks.
"They like the
agitation," explained lab manager Nathan Margolis.
In the pretreament
room, materials such as switch grass, corn stover, wood chips, and paper
sludge get heated and turned into a substance the color of coffee grounds
that resembles ripped-up peat moss.
Eventually, everything
gets tossed together in a fermentation tank that looks like an oversize
French press accessorized with random tubes.
"This is where
the action is," Margolis said of the dark beer-like substance brewing
in the tanks. "At the end of the day we're going to send it over
to analysis and find out, you know, how much ethanol is in there. More
is better."
Environmentalists,
Massachusetts officials, and others are monitoring Mascoma's progress.
Ian Bowles, secretary
of the state Executive Office of Energy and Environmental Affairs, called
biofuel a key part of Governor Deval Patrick's energy vision.
The state recently
passed legislation giving cellulosic biofuels an exemption from the gas
tax.
"Job one is to
be an alternative to petroleum," Bowles said of such fuels. "The
second is to do that in an environmentally benign way."
Environmentalists
say that's going to be one of the biggest hurdles for companies like Mascoma
to overcome.
The Conservation Law
Foundation, a nonprofit environmental advocacy group with offices throughout
New England, is calling for a low-carbon fuel standard that would scrutinize
every fuel - not just biofuel - and its production, and regulate and rank
them based on which pollute the least through their life cycles.
"You are looking
at how to get the greatest greenhouse gas reductions from every step in
the process rather than just at the tailpipe," said Shanna Cleveland,
a staff attorney with the foundation.
|