Life cycle assessment of biofuels in Thailand: Implications of environmental trade-offs for policy decisions

Biofuels have often been considered to have an advantage towards global warming but have caused controversy over competition for the limited availability of natural resources and the adverse impacts on other environmental aspects. This study evaluates the environmental benefits and impacts of biofuels in Thailand by using life cycle assessment with the Thai Eco Scarcity method derived from existing policies in Thailand. The assessment results showed that E85 (85% ethanol from cassava blended with 15% gasoline) and palm biodiesel had 95% and 43% higher impacts than their fossil fuel counterparts. The evaluation of biodiesel and ethanol revealed many trade-offs between environmental impacts; for example between fossil energy resources and other natural resources i.e. freshwater and land, and also between global (greenhouse gas emissions) and local impacts (pesticides). The importance of using the life cycle thinking concept which avoids problem shifting between impacts and between life cycle stages was also revealed. This is a crucial message in policy-making which has largely equated environmental impacts with greenhouse gas emissions leading to unintended consequences on other impacts. As anticipated, both biofuels perform much better than their fossil counterparts when considering greenhouse gas emissions and fossil energy resources. However, including other impact categories, particularly land and freshwater resources, pesticides use and mineral resources completely reverses the comparison, with the fossil counterparts ending up with better environmental profiles. Using a policy-based life cycle impact assessment method reveals comparative results and trade-offs on a single scale which can be easily understood by the policy-makers. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.