Bioenergy

Helping Tongans Turn Coconuts into Biodiesel

Brigham Young University (BYU) student engineers returned from Tonga last week after successfully demonstrating to locals a better way to produce fuel — showing that it can, in fact, grow on trees. More potent than pina coladas, the coconut oil biodiesel fuel the student team produced from modified chemical reactors, could, after further development, have the potential to help the South Pacific island nation’s economy and mitigate soaring fuel prices.

“The Tongan economy was centered around exporting coconuts and coconut oil until the ‘80s when soybean oil drove coconut producers out of business,” explained Allyson Frankman, a chemical engineering Ph.D. candidate who played a major role in the project. “Farmers and processors were devastated, and the economy has never really recovered, but the coconuts are still there—they litter the ground.”

The process to turn coconuts into diesel fuel starts with the meat, or copra, of the coconuts. The meat is grated, dried and then pressed to extract the coconut oil. The oil is then mixed with two chemicals, methanol and sodium hydroxide, in the reactor for two hours to transition the oil into clean-burning fuel. The byproduct of the process, glycerol, can be made into soap or compost and sold along with the rest of the coconut husk and meat.

“It is a relatively simple process,” said Jacob Jones, undergraduate student team leader of the BYU group, which ranged from sophomores to graduate students and represented a variety of engineering backgrounds.

BYU faculty were first approached by members of the Havea family, a Tongan family interested in biodiesel and eager to get some assistance in the technical and business elements of the process. The answer came in the form of a special BYU class, Global Projects in Engineering and Technology, which created multidisciplinary teams and pitted them against actual challenges.

After a full semester of studying coconuts, from their chemical composition to economics, the student team and faculty instructors visited Tonga for two weeks earlier this month. There they trained locals to operate the biodiesel reactor and staged demonstrations for high schools and government ministers, with the latter culminating with a diesel engine running on a sample of freshly minted coconut biodiesel.

“The [goverment] ministers were ecstatic and want to pursue the utilization of biodiesel further,” said Randy Lewis, a professor of chemical engineering, who, with fellow chemical engineering professor Vincent Wilding, functioned as course instructors and advised the teams. “Our students were able to strengthen their abilities to solve real-world problems. They were able to realize their potential in working among engineers from different disciplines.”

Among the officials and news media at one of the demonstrations were representatives from the Tongan Minister of Tourism and the Tongan Minister of Land, Survey and Natural Resources, whose spokesperson said biodiesel was being considered as a source of income for the Kingdom. 

“If it will be proven cheaper, then it can be produced locally, with a minimum import of methanol and sodium hydroxide,” the spokesperson said, as reported in Tonga Now. “It will be a form of employment, and can be exported to other countries that produce biodiesel, which in turn can boost the exportation level . . . With many countries and organizations such as the European Union and the Pacific Forum placing emphasis on renewable energy, the idea of biodiesel [made from] coconut oil seems promising for Tonga.”