Scientific, technocal and financial challenges of achieving a biofuels industry

Abstract

Despite many years of intensive research and development-supported by billions of dollars of government subsidies, grants and loans - biofuels are commercially produced today almost exactly the same way as 20 years ago: ethanol from sugar cane in Latin America and corn grain in the Midwest United States. Biofuel production technology developments in progress include three broad categories: purely biochemical, purely thermochemical, and hybrid technologies that incorporate elements of both. None have achieved commercial success thus far. The current situation is due to a combination of technical factors which lead to inadequate financial return to investors: (1) process complexity requires capital investment per unit of ethanol produced through biochemical route is too high (by a factor > 2); (2) published yields of ethanol, based on the carbohydrate content of biomass, is only 70% of potential; (3) cellulytic enzymes - in the case of the biochemical route - cannot currently achieve a level of cost-effectiveness required to achieve biofuel production cost adequate for profitability; and (4) woody biomass is generally too expensive, and non-wood biomass insufficiently abundant to provide attractive cash production costs. On a broader scale we believe success has not been achieved because the research has focused on only one or two of the key elements of technology development and have not integrated the full land - to - biomass - to - conversion technology-to market supply chain. We discuss four areas where science is needed to make a breakthrough: 1. Better integration of land and bioenergy plantation economics to provide abundant, affordable biomass feedstock. 2. Bioengineering improvement of biomass feedstock to increase carbohydrate (biochemical) or lignin (thermochemical) content. 3. Other bioengineering improvements to reduce the recalcitrance of biomass through the various steps required to achieve high product yields. 4. Simpler process designs that achieve capital efficiency. Biofuels must always compete with petroleum derived fuels on a cost basis. Today, one might say we are far away from that goal, but in reality, it will be a combination of meaningful improvement in all of the key cost drivers that will lead to financial success. Science is needed to alter today's calculation, because incremental changes to current technology will not be adequate. Our research Team at North Carolina State University has developed a foundation to simulate - both technically and financially - integrated biomass - to -biofuels conversion technology options and have identified promising alternatives incorporating current and projected advances in each area of the chain.