An introduction to life cycle assessment with hands-on experiments for biodiesel production and use

This paper describes a hands-on project that introduces first year engineering students to life cycle assessment (LCA) through the comparison of the environmental impact of the production and use of three diesel fuels: petroleum diesel, biodiesel from new vegetable oil, and biodiesel from waste vegetable oil. The purpose of this LCA project was to incorporate life cycle thinking into the engineering design process, to apply the four main steps of LCA (definition and scope, inventory analysis, impact assessment and improvement assessment), and to explore some of the challenges associated with each step. The inventory for biodiesel production (from both new and waste vegetable oils) was based on measurements obtained by the students in laboratory experiments. The fossil diesel production inventory was obtained from the SimaPro^® database. The inventory for the use of all three fuels was obtained from measurements taken during combustion of the fuels in a generator. A cradle-to-grave life cycle analysis was then conducted using SimaPro^® for each fuel. The assessment of learning outcomes indicates a significant increase in conceptual understanding of the four stages of life cycle assessment, and an average gain of over 55% in overall knowledge of life cycle assessment.