U.S. Biofuels Industry: A Critical Review of the Opportunities and Challenges


  • Min Chen The Pennsylvania State University
  • Paul M. Smith The Pennsylvania State University
  • Michael P. Wolcott Washington State University


Biofuels, Blend wall, Food vs. fuel, Renewable Fuel Standard (RFS), Low Carbon Fuel Standard (LCFS)


Due to climate change concerns, governments and consumers are demanding increasing environmental accountability for transportation fuels, particularly as related to carbon emissions.  Additionally, the U.S. policymakers seek renewable alternatives to enhance energy security, reduce oil price volatility and increase rural economic development opportunities. These issues present an emerging market opportunity for lignocellulosic materials, while posing various challenges to industry scale-up. The review begins with first generation corn-grain ethanol and biodiesel, today’s most widely available biofuels within the U.S. Further growth of these biofuels may be limited by the “blend wall”, the “food-versus-fuel” debate, and land use change inssues. As a result, industrial, governmental and academic research interests have shifted to second and third generation biofuels produced from lignocellulosic biomass and algae to address GHG emissions and the food-fuel issue. Limiting factors to the scale-up of these hydrocarbon drop-in biofuels include feedstock costs and availability, high production and capital costs, policy uncertainty, and various technical, environmental and social issues.  This paper builds on previous literature and online secondary sources to present a comprehensive and current inventory of existing U.S. biofuel players, a thorough review of the U.S. biofuels industry and lessons learned from corn/grain ethanol applied to next generation lignocellulosic biofuels.

Author Biographies

Min Chen, The Pennsylvania State University

Fourth year Ph.D. Candidate of BioRenewables System (BRS)

Department of Agricultural and Biological Engineering

Paul M. Smith, The Pennsylvania State University

Professor of Bioproducts Marketing

BRS Graduate Program Coordinator

Department of Agricultural& Biological Engineering

Michael P. Wolcott, Washington State University

Louisiana-Pacific Distinguished Professor

Department of Civil & Environmental Engineering


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