Texas Agricultural Engineering Experiment Station,
Texas A & M University

A number of cutting-edge research efforts, all related to bioenergy, are being conducted by the Texas Agricultural Experiment Station scientists. The United States’ bioenergy goals—35 billion gallons of ethanol production by 2017 and 30% of transportation fuels being biofuels by 2030—have added incentive and urgency.

To supply 30% or more of the nation’s transportation fuels requirements, 800 million tons of cellulosic biomass from agricultural sources will be required for the production of biofuels. This biomass will come from crop residues and dedicated high-yield bioenergy crops that do not compete with food crops.

The Texas Agricultural Experiment Station is actively seeking, on a number of fronts, solutions to the bioenergy issues and a means of helping this nation become energy independent. Strategies and incentives are being developed to concomitantly foster both biofuels development and environmental stewardship.

Ongoing Study for Dedicated Bioenergy Crop: High-yield Sorghum

Sorghum genetic resources will be screened for sources of improved yield and biomass composition (sugar content, cellulose, hemicellulose, lignin) optimal for biofuels production. Sorghum germplasm, traits and genes that improve biomass yield, bioenergy composition, and drought tolerance will be identified and pyramided into cultivars and elite hybrids. Advanced material will be tested to identify cultivars that have optimal biomass-to-biofuels conversion properties. Logistical approaches will be optimized for the harvest and transport of sorghum to facilities for biofuels production. The conversion of cellulosic biomass to biofuels must be improved to meet U.S. production goals.

Necessary Systems Development: Production, Harvesting, Transportation, Storage

Refinements are being made to make high-yield sorghum even more efficient. Further study is necessary to develop tillage systems, planting density/harvest regime, fertilizer and water requirements, rotation, and plant protection. Harvesting equipment will be evaluated in field conditions. Transportation systems must be selected effective delivery. Storage systems will be tested for moisture content and composition of biomass.

Other Biofuels Crops

Sugarcane is another biomass option, but it only thrives in limited southern coastal areas. The Texas Agricultural Experiment Station researchers are redesigning sugarcane to extend its range (making it more cold tolerant) and to increase its sucrose content. Though switchgrass cannot be rotated as a regular crop, grass hybrids are being studied for their utility as potential biomass. Mesquite covers more than 70 million acres of Texas rangeland and could be used for bioenergy.

Cattle Manure: Premier Biomass

Concentrated animal feeding operations (cattle, swine, poultry) produce residuals of manure, wastewater, carcasses, and unused feedstuffs—all sources of nutrients and renewable energy. Collectible manure from beef and dairy feedlots in Texas amounts to 4 million dry tons per year. The vast quantity of feedlot biomass is a premier bioenergy feedstock with great potential for bioenergy production in the state, the nation, and the world.

Agricultural Experiment Station technologies that utilize the heating value of feedlot biomass include biological conversion (anaerobic digestion for biogas/methane production) and thermochemical conversion (gasification, combustion in cofiring/reburning, pyrolysis). Another technology that has been developed provides a clean, renewable source of energy as well as reducing nitric oxide emissions: using feedlot biomass as reburn fuel in coal or lignite-fired plants. Other Agricultural Experiment Station technologies reduce the emissions of greenhouse gases (carbon dioxide, methane), odorous gases, particulate matter, and ammonia. Researchers have shown that, with as little as 10% high-quality manure, nitrogen oxides could be reduced by up to 80% in coal-fired power plants.

By precise feedlot manure management, ammonia emissions and the energy loss by methane could be minimized and global warming reduced. Ongoing studies explore efficient handling and processing of feed, water, animals, and waste, converting waste to profitable products and reducing nutrient loading and emissions; thermochemical energy conversion technology; instrumentation engineering/information technology for cheap, reliable means of obtaining real-time efficiency data for feedlot operations processes; and gauging rural economic impacts of a biorefinery approach to renewable energy and coproduct extraction.

Economical Refining of Heavy Oils

Electron beam treatment of crude oil has good potential for processing heavy oils into light, well-flowing fluids at greatly reduced oil refining costs. Though heavy oil accounts for 8 trillion barrels of global resources, only one percent of heavy oil reserves are processed due to technical difficulties and high refining costs. Agricultural Experiment Station scientists are experimenting with heavy oils, using electron-beam irradiation to transform them into light fluids.

Economic Forecasting: Biofuels Market Prospects and Plant Financial Success

The emerging phenomenon of biofuels production profoundly affects the world of agriculture. Biofuels market structures are rapidly evolving, and energy and agricultural policies are becoming entangled. There is a need for new approaches for evaluating biofuels projects under alternative policies and in evolving market conditions. Texas Agricultural Experiment Station scientists have created a model that provides projections of biofuels industry activities and market conditions in the U.S., considering commercialized production technologies, fossil-energy and agricultural market conditions, and government policy and their interactions. Output from this model adds reliability to feasibility analyses of commercial-scale production of biofuels. Present and past analyses of this type include grain-based ethanol production in Texas, large-scale biomass to mixed fuel alcohol production, and the feasibility of integrating ethanol production at U.S. sugar mills. Further work planned in this arena is to generate timely, credible, probabilistic forecasts of renewable fuels production levels/prices and to provide feasibility analyses that are far superior, given the linkage to timely biofuel market projections.