Advanced biohydrocarbons are similar to conventional hydrocarbon fuels such as gasoline or diesel but are produced from biomass feedstocks, such as woody biomass or algae, through a variety of biological and chemical processes. Advanced biohydrocarbons are considered a ‘drop-in’ fuel; in other words, their use does not require significant modifications to existing fuel distribution infrastructure or vehicle engine modifications (for gasoline or diesel powered vehicles), unlike ethanol as it is used today. Similarly, the energy content of advanced biohydrocarbons is equivalent to that of their petroleum-based counterparts (i.e., gasoline and diesel).
Manufacturers can produce advanced biohydrocarbons by four primary pathways:
Figure 1: Production Pathways for Advanced Biohydrocarbon Fuels
This figure illustrates a) chemical (black), b) biological (green), and c) thermal (red) production pathways for advanced biohydrocarbons derived from i) woody biomass and ii) algae. The production of gasoline or diesel equivalents is dependent on the technology and pathway. Note that while jet fuel can also be produced, it is not discussed further in this summary.
Environmental Benefit / Emission Reduction Potential
The environmental benefits of advanced biohydrocarbons are significant. For instance, they have the potential to overcome obstacles related to the use of ethanol: land use changes; transportation and distribution of finished fuel; impacts on other agricultural commodities; and the need for vehicle modification.
The primary feedstocks for advanced biohydrocarbons are woody biomass (primarily food and agricultural waste) and algae — neither of which have the same land requirements as biofuels derived from traditional food or feed crops (such as corn or sugarcane). While there will inevitably be some pressure on agricultural lands and forestry resources, the impacts are less than first generation biofuels.
The development of heterogeneous chemical catalysts, used in combination with biological catalysts to produce advanced biohydrocarbons, has the potential to improve biofuel production efficiency and reduce costs. Furthermore, advanced biohydrocarbon fuels are chemically equivalent to the fuels derived from petroleum, which may make it possible to link biorefining processes to existing petroleum refineries. This has the potential to reduce the environmental impact of construction of new refineries and distribution networks (e.g., pipelines), and other fueling infrastructure.
Advanced biohydrocarbons have the potential to reduce significantly the amount of water used in feedstock production and in fuel processing compared to the crops for “first generation” biofuels and the processing using dilute sugar solutions for ethanol production.
The greenhouse gas emissions reduction potential of advanced biohydrocarbons is significant. However, there are no reliable estimates of the GHG emissions (reported as grams per megajoule, g/MJ) of advanced biohydrocarbons because there are no commercial scale processes that can be used to develop the appropriate energy balance equations.
The Department of Energy (DOE) has estimated that the availability of domestic biomass streams, with “relatively modest changes in land use and agricultural and forest practices,” could yield advanced biohydrocarbons at a volume equivalent to approximately 30 percent of petroleum used in the United States by 2050. The oil yield of algal-based diesels is predicted to be as much as an order of magnitude higher than other biodiesel crops. Assuming a lower limit for the oil yield of algal-based biodiesel (30 percent by weight), only 2.5 percent of existing U.S. cropping area would be required to displace 50 percent of petroleum based diesel use in the United States.
The current cost of large-scale production of advanced biohydrocarbons is unknown, as only bench-scale production has been conducted thus far. As such, only estimates of cost are available at this time.
There are four primary factors that determine the cost of the finished product: the feedstock, chemical processing (e.g., pyrolysis), refining and finishing the crude product, and the transportation and distribution of finished fuel.
Feedstock: The cost of woody biomass feedstocks is dependent on a number of factors including, but not limited to: crop yield, land availability, harvesting, storage and handling, and transportation costs. Huber estimates a cost of $34 to $70 per dry ton, or $5 to $15 per barrel of oil energy equivalent. This is generally consistent with the BRDI review of the literature. They report costs for a number of advanced biofuel feedstock types, including agricultural residues (e.g., corn stover), forest biomass, urban woody wastes and secondary mill residues, herbaceous energy crops (e.g., switchgrass), and short rotation woody crops.
Catalyst: The long-term potential of advanced biohydrocarbons is linked to the ability of producers to produce liquid fuels using cost-effective catalysts. Looking at existing catalytic processes, the DOE has a projected cost of cellulase enzymes for the production of ethanol between $0.30–0.50 per gallon of ethanol. In contrast, the chemical catalysts in the petroleum industry are estimated to cost about $0.01 per gallon of gasoline.
Refining and Upgrading: Estimates for refining and upgrading the bio-oil produced from pyrolysis or hydrolysis suggest that these steps account for about 33–39 percent of the capital costs of producing the finished product. The range varies due to the variable amount of refining and upgrading required based on the pathway.
Transportation: The cost of transporting biomass feedstocks can increase production costs considerably. The savings derived from economies of scale at centralized facilities are often offset by the increased transportation costs of the raw material(s). Developing a distribution system that is built on local and distributed production facilities rather than large centralized facilities will help reduce transportation costs.
In terms of net production, various start-up companies have claimed that they anticipate that in the long term, advanced biohydrocarbons will be competitive with conventional petroleum products at oil prices of about $40–60 per barrel.
Advanced biohydrocarbons are currently in the development and demonstration stage. A variety of processes have been demonstrated using bench-scale reactors to produce liquid fuels and liquid fuel components (e.g., aromatic compounds). Most estimates suggest that commercial scale production of advanced biohydrocarbons will begin within the next five to ten years.
Most recently, the DOE’s ARPA-E awarded seven projects (out of 37) a total of $37.2 million (out of $151 million) in areas related to advanced biohydrocarbons as part of their solicitation for Transformational Energy Research Projects.
The DOE awarded $78 million for the development of ‘drop-in’ renewable hydrocarbon biofuels such as advanced biohydrocarbons and associated fueling infrastructure.
Within the past year alone, five major oil companies – BP, Chevron, ExxonMobil, Royal Dutch Shell, and Total – announced joint ventures with biofuel companies to work on the development of advanced biohydrocarbons.
Obstacles to Further Development or Deployment
Currently, there are no low-cost technologies to convert the large fraction of energy in biomass or the bio-oils derived from algae into liquid fuels efficiently. Production costs must be reduced considerably, and the production volumes necessary for widespread use still need to be demonstrated. The lower limit benchmark for commercial scale processing of biomass is about 150,000 metric tons per year.
Ultimately, the optimization of advanced biohydrocarbon production processes is an essential step to allow biorefineries to produce up to commercial volumes. These barriers exist in processes such as selective thermal processing, liquid-phase catalytic processing of sugars and bio-oils, and catalytic conversion of bio-gas.
Policy Options to Help Promote Advanced Biohydrocarbon Fuels
Federal, state, county, and local governments support advanced biohydrocarbons in a variety of ways. Although current policies are aimed at alcohol transportation fuels, recent debate over the potential environmental and societal impacts of using feed and food crops for energy production has bolstered interest in biofuels produced from non-food feedstocks. Current support for advanced biohydrocarbons generally falls into three categories: 1) policies that mandate levels of use of biofuels, 2) policies that offer subsidies or tax credits for fuel production and/or use, and 3) and research initiatives.
Existing taxes and subsidies
Other tax and subsidy policies that may be considered:
Related Business Environmental Leadership Council (BELC) Company Activities
Related C2ES Resources
Climate TechBook: Biofuels Overview , 2009
Climate TechBook: Biodiesel , 2009
Climate TechBook: Cellulosic Ethanol , 2009
Climate TechBook: Ethanol , 2009
Further Reading / Additional Resources
Biomass Energy Data Book , 2008.
Green Car Congress, Bio-Hydrocarbons .
National Biofuels Action Plan , October 2008, Biomass Research and Development Board
Biomass Research and Development Initiative (BRDi), “The Economics of Biomass Feedstocks in the United States, A Review of the Literature ,” 2008.
Chisti, Y. (2007). Biodiesel from microalgae. Palmerston North: Biotechnology Advances.
Hubert, GW, et al. “Synthesis of Transportation Fuels from Biomass: Chemistry, Catalysis, and Engineering.” Chemical Reviews, 2006, 106, pp. 4044-4098.
Perlack R., L. Wright, A. Turhollow, R. Graham, B Stokes, and D. Erbach, Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply, USDA/DOE, DOE/GO-102005-2135, ORNL/TM-2005/66, April 2005.
Regalbuto, J. “Cellulosic Biofuels – Got Gasoline?” Science, Vol 325, 5492, pp. 822-824, August 2009.
NSF. “Breaking the Chemical and Engineering Barriers to Lignocellulosic Biofuels: Next Generation Hydrocarbon Biorefineries”. Ed. George W. Huber, 2008, 180 p.
Green Car Congress, “Terrabon to Open New Demonstration Facility Next Week for Biomass to Renewable Gasoline Technology ,” October 2008.
Wu, M.; Mintz, M.; and Wang, M. Water Consumption in the Production of Ethanol and Petroleum Gasoline,” Env Mngmt, 44, 981-997, 2009.
 See Perlack R., L. Wright, A. Turhollow, R. Graham, B Stokes, and D. Erbach, Biomass as Feedstock for a “Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply,” USDA/DOE, DOE/GO-102005-2135, ORNL/TM-2005/66, April 2005. In their report, Perlack et al. answer the question as to whether the “land resources of the United States are capable of producing a sustainable supply of biomass sufficient to displace 30 percent or more of the country’s present petroleum consumption.” Their scenario assumes “relatively modest changes” in land use and agricultural and forestry practices. In other words, the report evaluates the resource availability, rather than the economic viability of biomass as a feedstock for transportation fuels.
 An example of a biological catalyst is yeast in the fermentation of sugars yielded from the starch in corn or sugarcane. Biological catalysts in fermentation (to produce alcohol) have been used for thousands of years.
 Heterogeneous catalysts are those that are in a different phase (i.e., gas, liquid, or solid) than the reactants.
 Wu, M., Mintz, M., and Wang, M. “Water Consumption in the Production of Ethanol and Petroleum Gasoline,” Env Mngmt, 44, 981-997, 2009.
 Perlack et al. 2005.
 Chisti, Y. Biodiesel from microalgae. Palmerston North: Biotechnology Advances. 2007.
 Biomass Research and Development Initiative (BRDi), “The Economics of Biomass Feedstocks in the United States, A Review of the Literature ,” 2008.
 Hubert, GW, et al. “Synthesis of Transportation Fuels from Biomass: Chemistry, Catalysis, and Engineering.” Chemical Reviews, 2006, 106, pp. 4044-4098.
 National Science Foundation, “Breaking the Chemical and Engineering Barriers to Lignocellulosic Biofuels: Next Generation Hydrocarbon Biorefineries,” Ed. George W. Huber, 2008, p. 180.
 NSF/Huber 2008.
 Regalbuto, J. “Cellulosic Biofuels – Got Gasoline?” Science, Vol 325, 5492, pp. 822-824, August 2009 and Green Car Congress, “Terrabon to Open New Demonstration Facility Next Week for Biomass to Renewable Gasoline Technology ,” October 2008,” October 2008.
 LS9. “LS9 Secures $25 Million in Latest Round of Funding .” Press Release, September 2009.
 Shell and Codexis. “Shell and Codexis Deepen Collaboration to Speed Arrival of Next Generation Biofuel .” Joint Press Release, October 2009.
 Gevo, Inc. “Major Oil and Gas Company, Total, Invests in Advanced Biofuels Leader Gevo .” Press Release, April 2009.
 NSF/Huber 2008.
 U.S. Department of Energy. Alternative Fuels and Advanced Vehicles Data Center – Federal and State Incentives and Laws . Last accessed March 19th, 2010.