March 25, 2008

UNH researchers pursue algae in hopes to make fuel consumption greener

Amanda Flitter

In a corner of Morse Hall 103, surrounded by foil-lined cardboard and fluorescent lights, looms a glass container of green liquid. The green liquid churns as bubbles float up to burst at the surface. Two beakers containing samples of the green liquid are connected to machines by clear tubes that weave and curl their way out of the stoppered tops.

The set-up seems like a scaled-down version of a mad scientist's lab, but the boiling contents of the container, called a bioreactor, could be the key to the next step in alternative energy. That is because the green liquid is full of algae, the microscopic plant that is the new poster child for biodiesel production.

"It's definitely an alternative source of energy we should be looking into," said Thad Webster, a junior who works in the lab. "If algae can grow and produce more in worse conditions [than food crops], we should utilize that."

Biodiesel is made from vegetable oil, which is composed of fatty acids and glycerin. In order to make it, alcohol is added to vegetable oil to break apart the fatty acids and the glycerin. The alcohol then combines with the fatty acids and the glycerin settles out, leaving pure biodiesel. The advantage of biodiesel is it burns cleaner and can easily be substituted for regular diesel. It is also carbon neutral, which means all carbon dioxide released into the atmosphere from burning it is taken up by the next generation of biodiesel crops during photosynthesis. However, biodiesel has generated controversy due to the ethical dilemma of using large quantities of food crops, like soybeans and corn, for its production. In some countries, farmers are paid more to sell their crops for biodiesel production than for food due to high demand for biofuels in Europe and the United States. The food crops are then scarcer, driving up prices and as a result, poor people go hungry.

"It's creating this ethical dilemma now of do you use the land to make food or energy?" said chemical engineering professor Ihab Farag.

In addition to ethical problems, there is the practical problem of the amount of crops needed for large-scale biodiesel production. Farag said one acre of soybeans could produce 60 gallons of biodiesel; it would take 20,000 acres of soybeans to generate 1 million gallons of biodiesel. Annually, the United States uses about 60 billion gallons of diesel fuel per year.

Farag said substituting all the United States' diesel with crop-based biodiesel is "unrealistic."

Algae, however, could hypothetically make these issues obsolete.

One acre of algae generates 5,000 to 15,000 gallons of biodiesel, according to Farag. However, algae do not need arable land to survive; only a pool of nutrient-rich water is needed. This solves the ethical land use problem. Also, algae grow in a week, compared to 6 to 9 months for corn.

In order to grow enough algae to replace all diesel used in the United States, an area half the size of Texas would be needed, according to Farag.

"It's still a big area, but not as huge as we were talking about [with food crops]," he said. Since algae thrive in a carbon-rich environment, he said, municipal wastewater would be an ideal nutrient source. The algae would take up the carbon, cleaning the waste water by absorbing the nutrients it needs.

Algae could also be used to scrub power plant emissions. Jason Ouellette, a junior who works in the lab, said a coal plant could bubble its carbon dioxide rich emissions through water, growing algae for biodiesel while cleaning its emissions.

The first step in growing algae in the lab is placing them in beakers, where they are given light, air and nutrients. When they are mature enough, they are moved to a larger photo bioreactor, which bubbles air through a nutrient rich solution. As the algae grow, they produce the oil needed for biodiesel. The oil is extracted by breaking the algae cells using a machine called a cell disruptor.

No biodiesel has been produced from the algae so far. Ben Chiang, a sophomore who works in the lab, said they are trying to find the conditions that will yield maximum oil production. So far, he said, they have tried two different types of algae and are testing different kinds of water, such as freshwater, saltwater and pond water. They are now bubbling house air through the photo bioreactor, but he said they hope to get a carbon dioxide drip to bubble through.

Farag said there are many challenges facing algae research, including the issue of secrecy. He said the person who perfects algae for biodiesel could make a lot of money, so groups are keeping research under wraps.

"We're not taking advantage of knowing what others are doing," he said.

He also said there is concern that oil companies will resist the new algae technology.

However, Farag is hopeful about biodiesel's future. He said producing biodiesel here in the United States would cut down on imports and create jobs within the country, and using it would help clean up the air.

"Biodiesel is here to stay," he said. "I would hope people would look at it in a positive way."

Meanwhile, Farag and his students carefully tend the algae in hopes of creating fuel for the future.

"I'm hoping we'll see this in an actual plant," Farag said, watching the algae churn.

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