Life cycle emissions and energy study of biodiesel derived from waste cooking oil and diesel in Singapore

Background, aim and scope  

Biodiesel derived from Waste Cooking Oil (WCO) is considered highly environmentally sustainable since WCO is a waste product from domestic and commercial cooking processes and then recycled to a transportation fuel in Singapore. In addition, it avoids the conversion of land use for crop production. This is a strong advantage for Singapore which has relatively smaller land space than other countries. The import of virgin oil as feedstock into Singapore is also avoided. Therefore, the more appropriate feedstock to produce biodiesel in Singapore context is WCO. According to the National Environment Agency, diesel vehicles in Singapore contribute 50% of the total particulate matter smaller than 2.5 μm (PM_0.25) emissions to air ambient. Hence, the aim of this life cycle assessment study was to compare the environmental performances of biodiesel derived from WCO and low sulphur diesel in terms of global warming potential, life cycle energy efficiency (LCEE) and fossil energy ratio (FER) using the life cycle inventory. The results of this study would serve as a reference for energy policy makers and environmental agencies.