By K.C. Das
University of
Georgia
Recent scientific studies warn that increasing land use for producing biomass for biofuels would increase greenhouse gas, or GHG, emissions compared to gasoline. Some may disagree with these studies. However, they do show the weakness in expanding a crop-based fuel system without planning for sustainability.
If we continue to try to produce more biomass from the current spectrum of crop choices, GHG emission restrictions could put small biofuel producers and family farms at a disadvantage. Reduced emissions require crops that are easier to grow; require less money to plant, harvest and water; and are easier to process.
Needed production improvements
Corn ethanol production in the U.S. consumes a quarter of the country’s corn crop. Increasing ethanol production to the targeted 15 billion gallons a year by 2022 will double the corn required. That increase will impact land and water needs and create environmental concerns.We need to improve the productivity of corn and other biofuels crops and incorporate improvements into the production process.
Producing lignocellulosic ethanol or other advanced biofuels, or green diesel, is a challenge. Technology development in this field has advanced, but most U.S. facilities are still in the early-demonstration phase.
Using existing forestry and agriculture residues for biofuels would have minimal environmental impact while creating opportunity for small businesses and farms.
Forestry and agriculture generate significant biomass. According to the Department of Energy and the U.S. Department of Agriculture, forestlands can produce 368 million dry tons of biomass annually. Current legislative definitions make renewable forest biomass off-limits to biofuels companies. Definitions must be changed, while maintaining the resources' sustainability.
Data from the UGA Warnell School of Forestry and Natural Resources suggests collecting residues and producing chips for biofuel production costs $11 to $12 per ton delivered to mills.
Food v. fuel
It’s crucial that we have a diverse source of biomass that doesn’t compete with food supplies. Diversity allows different geographical regions to focus on crops best suited to local conditions. Current federal funding often favors specific feedstocks, hampering development and transfer technology for novel crops.Many novel crops are being explored. For example, a recent UGA study looked at using a multi-benefit winter cover crop, oil seed radish, for its biofuels potential. UGA scientists led a global team in sequencing the sorghum genome and are now working toward understanding how we can use the information to produce biofuels at lower costs in poor soils.
Targets eliminate possibilities
Targeted GHG reductions can unintentionally eliminate some promising technologies that are lagging behind because of late starts, such as algae-based biofuels.Anaerobic digestion, a well-developed technology, is not considered because the energy output (methane gas) isn’t a liquid transportation fuel at room temperature. A similar process called landfill bioreactor produces methane biogas which can be converted to compressed natural gas. Its GHG emissions are 17 percent less than its fossil-based equivalent.
Anaerobic digestion can create jobs and produce net income to farms and small biofuels producers. UGA researchers are developing a system that combines anaerobic digestion with algae production.
Current regulatory policies don’t readily support developing such integrated solutions in early development. More pilot-scale testing could help move them to the marketplace faster. Federal agencies seem focused on large-scale demonstrations before pilot-scale research is completed.
Welcomed policy change
Carbon sequestration is a welcomed change in national policy. Current regulatory emphasis favors carbon capture and storage through geological storage of compressed CO2. Although potentially a reliable technique, this approach favors larger-scale sequestration.One example of a smaller-scale method is using biochar, a byproduct of pyrolysis, a high-temperature breakdown of cellulosic materials that produces a liquid hydrocarbon, which could be converted to green diesel or other liquid fuels.
Biochar has high carbon content and stays in the soil for decades, increasing agricultural productivity and sequestering carbon for a long time. However, the regulatory framework doesn’t favor developing this technology.
There is great promise for biofuels to augment our energy supply. New ideas, technologies and discoveries are emerging from universities and research centers daily. Development and use of these discoveries could be faster if regulatory framework would support deeper exploration into novel crops that don’t pit fuel against food.
Encourage innovation
We need policies to encourage processes and technologies that create jobs and income for farms and small businesses. We need support that allows us to investigate diverse feedstocks and low-cost, efficient production methods that protect and enhance the environment.If we are to reach 36 billion gallons of biofuels in our transportation fuel mix by 2022 while reducing GHG emissions, all avenues of exploration must be open and barriers to development removed.
(K.C. Das is director of the Biorefining and Carbon Cycling Program with the University of Georgia College of Agricultural and Environmental Sciences and Faculty of Engineering. This editorial was presented as testimony before the U.S. House Committee on Small Business’ subcommittee on regulations and healthcare.)
