Big Green Bus

Witness the Big Green Bus. Hard to miss, even amid the glaring sun and smog at Bonnaroo. I happened upon the crew of Dartmouth students at the festival last year and got just a few minutes to chat with them. This year, I sought them out on the festival grounds and then met up with them again when they rolled into Seattle last weekend.

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During their 12,000-mile trek this summer, the Big Green Busriders are stopping at various events and landmarks ranging from a Doobie Brothers concert to Zion National Park to San Francisco Marathon Water Stop #3. And they’re filling up at mom-and-pop diners and greasy spoons all along the way.

So how exactly does an adventure like this get underway?

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bus interiorIt all started a few years ago when Dartmouth’s Ultimate Frisbee team needed a cheap way to get to tournaments. Once an old school bus, their ride is now outfitted with a veggie-oil filtration system and storage tanks, solar panels, a wind turbine, (student-installed) FSC-certified wood floors, and a flat-screen TV. Not too shabby.

And the goals have changed a bit too. No longer carting Frisbee players and gear, the Bus is a vehicle of change — carrying Dartmouth students who want to start a conversation about energy.

“We’re not trying to force any kind of solution on anyone; just to generate this dialogue,” says Dartmouth grad and Big Green Busrider Brent Butler. “We want people to argue with us. We want people to say, well, the reason biofuels are popular right now is because the U.S. government is subsidizing grains. (Of course, we have a surplus we need to get rid of, but normally biofuel is terrible.) These are the things we need people to start thinking about. Just to start questioning.”

So first question, Brent — how exactly does this thing work?

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bus engineDiesel engines were originally made to run on vegetable oil (peanut oil) … So the retrofit back to run on vegetable oil isn’t a terribly difficult process. The engine itself is pretty much the same. What you have to be able to do is filter the vegetable oil to a grade that is clean enough to run through your engine. Because we’re literally using what was, until very recently, frying french fries, fish, corndogs, whatever it is, we have to get all that extra stuff out so we’re just left with the veggie oil. We have to filter everything a couple times to do that.

The one concern then is vegetable oil is a little bit thicker than regular petroleum, which makes the engine run sticky because engines nowadays are made to run on petroleum. So we heat the oil before it goes into the engine, using energy from the solar panels and also heat from the engine itself. So we run the vegetable oil as a coolant around the engine — that keeps the oil nice and hot and makes it really smooth when it goes through our engine.

When you’re driving, there’s a little difference in power — you don’t get quite as much, but it runs much smoother. You don’t get that clunk of a diesel engine — it doesn’t sound as loud. But it also, instead of smelling like diesel, it smells like a McDonald’s, which we kinda dig.

For the 11 students and recent grads riding the bus this summer, the trip is all about education. The crew is well-versed in the inner workings of the bus’ fuel system and the pros and cons of alternative energy — whether sun, wind, or french fry grease — and they’re aiming to chat up everyone they meet. But they know this trip is just a first step.

“A weekend of listening to music and then on the side coming by to see a tent on biofuels isn’t enough to make an informed opinion at all,” Butler said. “It is enough to get you interested and then go do research on your own … so for that it’s great.”

And what does Butler plan to do once they make it home at the end of the month? Will he pursue a career in biofuels? Alternative energy? Environmental education?

“I’m actually going to try my hand at being a stand-up comedian.” Ha.