The Fuel of the Future - Potato Peel Ethanol!
Cindy Miao
Steveston-London Secondary
Floor Location : M 052 E

Bio-ethanol is a renewable energy source that can be used for transportation, industry, and heating. It can become an alternative to petroleum-based fuels, which not only produce high carbon emissions, but are also unsustainable and non-renewable. In 2014, 1.86 billion litres of corn and wheat derived ethanol was produced in Canada. However, because the ethanol was made from food sources, it competes with the food market and livestock feed industry. Limited amounts of raw materials were allocated for ethanol production, resulting in 1.27 billion litres of ethanol imported from the US in 2014 (as stated by the Renewable Fuels Association). Researchers are now looking to find other raw materials for ethanol production. In this project, potato peel waste was chosen as the feedstock because it is inexpensive and not considered as a food source. Furthermore, potato peels are plentiful: potatoes make up 52% of all fresh vegetables consumed in Canada; and potato peels are the by-product of many potato manufacturing industries. In this study, the optimum conditions for conversion of potato peels to ethanol were investigated to determine its feasibility for commercial ethanol production. Test factors include the type of yeast, the potato peel concentration, and the dose of enzyme. Leftover starches on potato peels are broken down into simple sugars that are fermentable by Saccharomyces cerevisiae (i.e. baker’s yeast). This process—starch hydrolysis—is done by various starch-degrading endo- and exo- enzymes. Sprouted barley malt is used in beer brewing and contains these starch-degrading enzymes. Thus, it was used as a source of enzymes during the starch hydrolysis process. This study is currently ongoing. From recently conducted experiments, it is expected that a larger dose of enzymes (20g of barley malt/250mL of mash), a higher potato peel concentration (1.5mL of water/g of peels), and brewer’s yeast will yield the most ethanol (about 8mL/90g of peels).