Potential for Sustainable Biofuels in California: Opportunities and Issues

Bioenergy, the application of biology to the energy sector, offers monumental challenges and opportunities at the interfaces of various technological, societal, and environmental futures. In particular, advanced biofuels that can make use of current infrastructure to meet the need for energy dense fuels in the near term, have a key but controversial role. It is widely acknowledged that bioenergy development and implementation must be approached with careful forethought and planning to avoid unintended consequences.  The ability of various biofuel technology pathways to meet future demand is shaped by physical, economic, and political constraints. Concerns over energy security, and long-term environmental, economic, and social sustainability are at once driving and impeding investment and innovation in development of new bioenergy pathways.  This has created an uncertain environment for policy makers and for initial commercialization efforts.  In an effort to understand the implications of biofuels in the context of California's Energy Future in 2050, two scenarios implementing different mixes of biofuels in California were examined.  In keeping with the executive mandate, state resources were analyzed in detail in the context of nation-wide and global biorenewable energy efforts.  The state could supply up to one-fifth the liquid fuel demand in 2050 from agricultural and forest residues, with reasonable efficiency measures.  If high-yield energy crops are implemented, around 75% of the fuel demand could be met by bioenergy.  The fuel mix and production pathways greatly impact the greenhouse gas savings.  Implementation of cellulosic E85 is insufficient to meet the governor’s goals without additional GHG savings in other parts of the energy portfolio; however, the development of drop-in advanced hydrocarbon biofuels could theoretically meet the mandate.  Issues surrounding supply and sustainability of feedstocks, commercialization and scale-up of emerging technology, and uncertainties in greenhouse gas reductions will be discussed.