抄録
Various kinds of vegetable oil and waste cooking oil are in fact used as car fuel all over the world. In general, 'bio-diesel' i.e. fatty acid methyl ester extracted from such oil is utilized as fuel for vehicles. However bio-diesel has some problems such as by-product and waste materials created during transesterification. An alternative method is the direct use of vegetable oil as car fuel through installation of a heater unit in the car to decrease vegetable oil viscosity. However little data has been reported concerning this method. The authors of this study carried out performance tests on the direct use of waste cooking oil using a car with a heater unit and found its high potential. Moreover, the authors compared the environmental load of direct use with bio-diesel and light oil by carrying out life cycle inventory to clarify the superiority of direct use.