Project at a Glance

Title: The Future of Drop-In Fuels: Life-Cycle Cost and Environmental Impacts of Bio-Based Hydrocarbon Fuel Pathways

Principal Investigator / Author(s): Horvath, Arpad

Contractor: UC Berkeley

Contract Number: 13-308

Research Program Area: Climate Change

Topic Areas: Greenhouse Gas Emissions, Mobile Sources & Fuels


Biofuels that can serve as a one-to-one replacement for gasoline or diesel, or achieve higher-level blends without modifications to existing fueling infrastructure and engines, offer an opportunity to accelerate the deployment of low-carbon liquid fuels. In this report, we reviewed the completed and ongoing research related to drop-in fuel production from feedstocks that can be produced in California, assessed potential pathways for conversion of biomass to hydrocarbon fuels from "well to pump" (excluding tailpipe combustion emissions) on the basis of expected cost, energy use, GHG emissions, criteria air pollutant emissions, water use, and technical potential in California, and modeled potential pathways to scaling up drop-in fuel production in the state. Biomass sources considered included crop residues, forest residues, primary mill waste, secondary mill waste, and urban wood waste. Our findings suggest that thermochemical pathways are the most promising routes in the near- and mid-term, although further research may improve yields for biological and hybrid biological/catalytic routes. Uncertainties associated with the results are significant due to lack of data, data quality, and scale-up scenarios for California conditions. Bio-based hydrocarbon fuels have the potential to have lower life-cycle greenhouse gas (GHG) emissions relative to comparable first generation fuels, such as ethanol or biodiesel, because truck and rail transportation can be partially eliminated in favor of energy-efficient pipelines. The criteria air pollutant emissions may also not be higher than for conventional fuels. We find that pyrolysis, Fischer-Tropsch, and methanol-to-gasoline routes can be scaled up using waste biomass in California to reach as high as 58% displacement of in-state diesel use and 8% of in-state gasoline use.

For questions regarding this research project, including available data and progress status, contact: Research Division staff at (916) 445-0753

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