The U.S. is looking for ways to depend less on foreign oil and reduce greenhouse
gas emissions. A popular method is so-called bio-fuels. Those are fuels, such as
ethanol or bio-diesel, made from plants. Cleaner burning bio-diesel has been billed
as an environmentally-friendly replacement for our 60 billion gallon a year thirst for
diesel oil. But there aren’t enough crops or land to produce enough bio-diesel to
replace fossil fuel-based diesel. Amy Quinton reports new research is looking at
another way to make bio-diesel: using algae:
Transcript
The U.S. is looking for ways to depend less on foreign oil and reduce greenhouse
gas emissions. A popular method is so-called bio-fuels. Those are fuels, such as
ethanol or bio-diesel, made from plants. Cleaner burning bio-diesel has been billed
as an environmentally-friendly replacement for our 60 billion gallon a year thirst for
diesel oil. But there aren’t enough crops or land to produce enough bio-diesel to
replace fossil fuel-based diesel. Amy Quinton reports new research is looking at
another way to make bio-diesel: using algae:
Bio-diesel is made primarily from plant oils: soybean, canola, rapeseed. Ihab Farag
is a chemical engineering professor at the University of New Hampshire. He climbs
up scaffolding to demonstrate a processor that turns waste oil from the University’s
cafeteria into bio-diesel. Farag says this is more environmentally-friendly than diesel:
“It’s coming from vegetable oil, so therefore it’s cleaner… it doesn’t have the sulfur in it so you
don’t get acid rain issue that you get from diesel, it doesn’t do particulates which are suspect[ed] to be cancer-
causing.”
Almost any diesel engine built in the last 15 years can use bio-diesel, but Farag says
there’s a major drawback: it takes an acre of most crops to produce only 100 gallons
of bio-diesel per year:
“I think it has been estimated that if we are using just something like soybean[s] and want to
produce bio-diesel for the whole country, we need almost an area of land that’s about
two and a half to three times the area of Texas.”
That would be an environmental nightmare because bio-fuels require a lot of fossil
fuels to plant, harvest and process them. They only produce a bit more energy than
the energy needed to make them. It also would put the nation’s fuel needs in conflict
with its food needs. That could drive the price of both sky-high.
So Farag and Master Chemical Engineering student Justin Ferrentino are looking at
another plant. One that’s capable of producing much more oil : algae.
Inside the University’s bio-diesel lab, Ferrentino holds up a glass jar filled with a sea-
green powder:
“This is freeze-dried cells that we’ve grown up in our photo-bioreactor.”
He’s testing different ways of extracting oil from these single-celled algae plants to
produce the most bio-diesel:
“People have projected with micro-algae you can grow somewhere between five and 15,000
gallons per acre per year, so it’s a big difference.”
Compared to 100 gallons per acre of soybeans, it’s a very big difference. Ferrentino
has built a contraption of two small fiberglass tanks, surrounded by florescent lights
and reflectors. It’s called a photo-bioreactor. With the right amount of light, the algae
here grows rapidly:
“When I fill these with growth medium and then add the cells to them and they just
multiply, they divide… they double every ten to 15 hours, when they’re growing
exponentially.”
The more cells, the more oil, and the more bio-diesel. Ferrentino’s photo-bioreactor
is small, producing only a tenth of a gram of bio-diesel. But build one on a larger
scale where there’s lots of sunlight, like the desert Southwest, and it could potentially
produce thousands of gallons on just an acre of land.
And Farag says because carbon is needed to fertilize algae growth, the potential
exists to remove greenhouse gases while simultaneously producing bio-diesel:
“If we can connect it with a wastewater treatment plant, where they have a lot of
waste coming in with lots of carbon in it then you can consume the carbon to grow
the algae and at the same time clean up the wastewater.”
But skeptics say one of the biggest challenges is making algae production
economical. Commercial production would initially yield fuel that could cost between
20 and 50 dollars a gallon. Ferrentino recognizes the drawbacks, but says their
research is worth pursuing:
“I think that our energy needs are not necessarily going to be solved with a magic
bullet, but I think this is certainly one part of it, being that you don’t need arable land
you have the added benefit of maybe being able to use the carbon from flue gases
from power plants, maybe being able to treat wastewater. So, it has some significant
added benefits so it could be one piece of the energy picture.”
But growing algae in the desert or anywhere else doesn’t have the kind of political
appeal that subsidizing farmers to grow soybeans for soy-diesel does. So finding
funding for a commercial-sized algae bio-reactor will face significant obstacles.
For the Environment Report, I’m Amy Quinton.
