Life Cycle Assessment of Biobutanol

Life Cycle Assessment (LCA) methodology is a rigorous framework to assess the environmental impacts of products, processes, and services. It is used as a metric to inform decision makers and policies of the climate change impact (expressed as Global Warming Potential (kgCO 2 eq)) of a wide range of renewable energies. This includes biofuels, the technologies which produce them, the feedstocks from which they are derived, and the end use of the fuel. LCA methodology is informed by ISO standards 14040/14040 that set rules for carrying out LCAs; however, the application of LCA methodology can be interpreted in different ways and on different levels, depending on the purpose of the LCA and the question(s) the LCA is intended to address. This chapter provides insight into the use of LCA to assess the performance of biobutanol as a renewable fuel, highlighting how differences in methodological choices can affect the outcome of LCAs for the same product (biobutanol). The chapter uses examples from published literature to demonstrate the way in which LCA methodology is applied and how interpretation of the results should be carefully considered before direct comparisons can be made between different feedstock sources and technologies used in the production of biobutanol. While most of the published literature addresses Global Warming Potential, reference is also made to wider environmental impacts and sustainability considerations for biofuels.