Bloomberg University Biofuel Bus Hibernates

BU's Biofuel Bus: “Bus #5.” photo by Dr. Mark Tapsak

BU’s first environmentally friendly shuttle bus, “Bus #5,” started running last April on biofuel made from used fryer oil. Since the fuel must be kept above 40 degrees at all times and the engine lacks the heating equipment necessary to maintain that temperature, the bus will have to hibernate when October comes.

The biofuel used in “Bus #5”— and all plant-based fuel— releases CO2 just like fossil fuels. But unlike fossil fuels, the plants were absorbing and removing CO2 from the atmosphere through photosynthesis before being harvested and turned into vegetable oil. By using plant matter, like vegetable oil, as a fuel, the overall effect is carbon neutral: the CO2 being released into the atmosphere from the biofuel was the same CO2 that was absorbed by the plants that created the biofuel.

The biodiesel provides approximately the same M.P.G. efficiency as regular petrodiesel with virtually no sulfur oxides and sulfates, two main components of acid rain.

Refining site for "BU Biofuel Initiative" on upper campus. photo by Dr. Mark Tapsak

The weekly refinery process is relatively simple. Used oil is collected from campus dining facilities and other downtown restaurants and brought to a greenhouse on campus that serves as the refinery site. Here the oil is transferred and filtered into a container resembling a residential water heater where it is heated and mixed with the appropriate ingredients.

“The recipe is—for every 100 gallons of vegetable oil we start with, we’ll add 20 gallons of methanol and a little bit of Sodium Hydroxide,” said Tapsak, Asst. Professor of Chemistry and Biochemistry.. Then the mixture is heated and cleaned via a week-long separation process. The end result is 100 gallons of biodiesel and 20 gallons of glycerol, the latter of which is composted.

Glycerol,the by-product, is used in hand lotion, soap and shampoo. This by-product can be sold or used to create a marketable campus soap.

Source: BU Now