Greenhouse gas and sustainability footprints of current and future biofuels for Queensland : Report for the Department of Environment and Heritage Protection

This report aims to provide insights into the greenhouse gas benefits and broader sustainability impacts of current and potential biofuels in Queensland. The sustainability credentials of biofuels have become more important recently with the implementation of the Queensland biofuel mandate.Life cycle assessment (LCA) is a methodology for quantifying the impacts of products and services across multiple environmental indicators and is standardised in the international standards ISO 14040 and ISO 14044 (International Organization for Standardization 2006, International Organization for Standardization 2006). This study, using the methodology outlined in those standards, followed the draft requirements for biofuels and bioenergy assessments currently being developed by the Australian Renewable Energy Agency (ARENA).There are many co-products involved in the biofuel supply chain. Some of the feedstocks used to make biofuels are co-products (such as molasses and tallow), and during biofuel production there are many co-products produced (such as canola meal, and glycerine). A range of approaches is available for dealing with co-products in LCA. System expansion was chosen as the approach for this study, which uses a substitution approach with competing products to credit or debit the biofuel system. This approach was selected as it better represents the reality of the many co-products being used and generated the biofuels arena. Alternative approaches such as apportioning impacts based on the economic and energy content of the products have been provided as a sensitivity analysis. The study examined 12 fuels including four sources of ethanol, six sources of biodiesel and two fossil fuels. The fuels assessed as the most likely blends were, for ethanol, a 10% blend of ethanol with unleaded petrol (E10) and, for biodiesel, a 5% blend of biodiesel with low sulphur diesel (B5). As blended fuels, there is no modification required to most vehicles or to fuel delivery infrastructure. A sensitivity analysis was undertaken to see if the results changed when 85% ethanol (E85) and 100% biodiesel (B100) were used.The environmental indicators included in the study were selected as the most important indicators likely to be affected by biofuel and fossil fuel production and use