Carbon footprint of renewable diesel from palm oil, jatropha oil and rapeseed oil

This paper examines the carbon footprint of renewable diesel (RD) production from palm oil, jatropha oil and rapeseed oil. Greenhouse gas (GHG) emissions from land use change (LUC), feedstock cultivation processes, and RD production and delivery are studied from a life-cycle assessment perspective. The goal of the paper is to calculate the carbon footprint of RD and recommend ways of decreasing it. Our findings indicate that the key contributors to the carbon footprint of RD are found in the GHG emissions of LUC, feedstock cultivation and oil extraction processes. In the case of palm oil, methane collection from palm oil mill effluent (POME) is one of the main contributors to the carbon footprint. Our calculations demonstrate that the RD production and distribution stages generate relatively low GHG emissions compared to the other life-cycle stages; therefore, attention should be focused on the contributing role of LUC and cultivation processes to the RD carbon footprint. If cultivation requires a land use conversion from forest to cultivated land, the resultant GHG emissions exceed emission levels from fossil fuels. If feedstock cultivation is done with no LUC or if grasslands are the feedstock cultivation site, then cultivation GHG emission reductions are achieved. In some cases, RD production may even act as a sink for GHGs. Due to its quality RD can be used without blend-wall limitations in vehicles; therefore, it offers a higher biofuel potential for the diesel sector than does traditional biodiesel. The article concludes by discussing the implications of the findings for RD in light of GHG emission reductions. (C) 2014 Elsevier Ltd. All rights reserved.