You don’t need to spend much time in a high school before hearing the “When am I ever going to use this?” complaint.

Although the question is posed less frequently in college classrooms, a sort of tunnel vision exerts itself and it’s just assumed that knowledge is to be applied to tests, exams and other forms of academic hoop-jumping.

Not so for four Goshen College biochemistry majors. With the help of chemistry Professor Doug Schirch, the group is using the know-how acquired through a biochemistry lab to create an on-campus biodiesel plant, which will eventually benefit both the school and the environment.

“It’s something students have heard about,” said Schirch, explaining why he began teaching the lab. “And a lot of students here are environmentally conscious, and interested in sustainability.”

When he learned that several other colleges and universities were making biodiesel on their campuses, Schirch asked his students if any were interested in producing the fuel on a larger scale.

Eventually, seniors Mitch Yoder, Neil Detweiler, Nate Herr, and junior Sae Chan Lee expressed interest. Now, the four hope to be producing biodiesel to be used on campus by the end of the semester.

Biodiesel is a non-petroleum-based diesel fuel that can be produced from vegetable oils or animals fats. It is usually mixed with petroleum diesel, and can be used in any diesel engine.

“Original diesel engines ran on vegetable oil,” said Schirch. “Later, they used petroleum as a substitute.”

Vegetable oil and petroleum diesel molecules are extremely similar, said Schirch. The chemical reaction used to extract and clean biodiesel from waste vegetable oil basically breaks down the vegetable oil molecules to about one third of their original size. The resulting fuel, which emits fewer pollutants and carbon monoxide and is biodegradable, can then be used to power diesel engines.

The waste vegetable oil will come from campus, too. The students will obtain around 12 gallons a week from the school cafeteria. In theory, they could also get waste oil from local restaurants, Schirch said, some of which sell or give it away. But the college won’t be soliciting off-campus waste donations; to do this, it would need to obtain a permit to transport waste materials.

The plant is located in the basement of the college’s heating plant in the same room where the heating plant’s diesel is stored. The waste vegetable oil will be strained, dumped into a vat and pumped into a tank where water, a result of foods being fried in the oil, is removed.

It’s then sent to a second tank, where the main methanol reaction occurs, catalyzed by lye. Finally, the glycerol is removed, excess methanol is reclaimed for reuse and the biodiesel is rinsed with water in order to flush out the lye. The rinse water is then dried, the fuel filtered again, monitored, then sent to the large diesel vat.

The whole process takes about two days.

“Quite a bit of time is taken just sitting,” said Schirch. “It’s like an Italian salad dressing,” in that you have to wait for the oil and water to separate.

The process is actually quite efficient, said Schirch. Approximately 80 percent of the waste vegetable oil is able to be converted to useable biodiesel.

Most of the fuel will be used for the campus generator, which kicks on whenever the school loses power. It’s also used during peak hours of electricity use, especially in the summer, when air conditioners are working hardest.

“The goal is to use less energy from the energy companies during peak hours,” explained Schirch.

Although the biodiesel will work in most diesel engines, due to road regulations, it can’t be used to power vehicles that drive off-campus. To lawfully drive on the road, a driver must be using fuel that has been taxed. There is, however, a possibility of powering campus lawnmowers and tractors with the homemade fuel.

If the production process sounds expensive, you might be surprised. Yoder said the entire project had a projected cost of around $6,000.

For funding, the group pitched its idea, which, according to Yoder, “was basically a business plan,” to the college’s recently formed Ecological Stewardship Committee.

The committee was created after Goshen College President Jim Brenneman signed the American College and University Presidents Climate Commitment. Part of that commitment is the promise that the school will work toward neutralizing its carbon emissions. And so the group also had to prove that the biodiesel plant would move the school toward carbon neutralization.

The students hope the project will pay itself off within three years. Already, it will be cheaper for them to make biodiesel than to buy petroleum-based fuel, and with the price of gasoline rising, said Schirch, they might pay it off sooner than they initially expected.

Until that day arrives, said Detweiler, “We’re still looking for a funding source.”

If this all seems too rosy, Schirch said biodiesel is not the answer to all the world’s environmental problems.

“Biodiesel is not a substitute for conservation,” he said. “This is just one small piece of the puzzle. We couldn’t run the whole college on this unless the students ate french fries four times a day.”