Competing for Land
Land Requirements of Texas Energy Resources
Each bar is sized to indicate the area needed to produce enough electricity or primary fuel to serve all annual energy needs for about 3,000,000 people.
Source: Virtus Energy
Texas is richly endowed with vast biomass resources (forest and agricultural wastes, farming wastes, municipal residues, landfill gas and energy crops) which produce heat, power generation, electricity, gas, motor fuel, fertilizer and many other products.
As one of the nation’s leading agricultural states and with a large forest and cattle industry, Texas has the potential to become a major biomass producer. The availability and type of biomass differs from region to region, but most biomass opportunities are located in rural areas. The state’s very large urban base also contributes to the energy pool with substantial amounts of biomass-derived wastes. If just half of Texas’ available biomass wastes were utilized for electricity production, they could supply 10% of the state’s needs.
But unlike most renewable energy sources, competition exists for both the biomass and the requisite land resource to grow it.
Although many specialists envision a role for biomass in which it is grown extensively and solely for fuel (energy crops), most land used for biomass harvesting must have some valued dual use or co-product derived from the crop. Eventually, these concerns may be redressed by cellulosic enzyme technology, which is being actively pursued at federal and state levels, as well as in the private sector.
In the future, fast-growing energy crops may become the biomass fuel of choice. These energy crops will be selectively bred to be fast growing, drought and pest resistant, and readily harvested, allowing them to become a competitively priced fuel. The U.S. Department of Energy is working with national labs, agricultural and forestry groups, power companies, and other governmental agencies to make energy crops a viable fuel source in the near future. According to the Natural Resources Defense Council (NRDC):
“Even under an aggressive growth scenario for the biofuels industry, land does not become a constraint until the mid-21st century, and we believe that farmers will find ways to meet traditional agricultural and energy demands on our existing croplands well beyond then.”
A 2005 joint study conducted by the Departments of Energy and Agriculture estimates that 1.3 billion tons of biomass feedstock is potentially available in the U.S. for the production of biofuels. This is enough biomass feedstock to displace approximately 30 percent of current gasoline consumption on a sustainable basis.
Texas Farmlands: Agricultural Residues
Biofuels and electric power generation can be produced from a variety of agricultural waste products, including cheese whey, beer and beverage waste. By far, the state’s major agricultural process residue is cotton gin trash, by-products of cotton ginning. Other locally abundant agricultural wastes include rice hulls, sugarcane bagasse, and cottonseed hulls.
Texas Biomass: Major Resource Areas
The primary agricultural wastes in the High Plains region are feedlot manure and cotton gin trash.
The East Texas timber industry operates at sustainable levels. Utilization of waste is high, but can still improve.
The primary agricultural wastes in the Gulf Coast, Alamo and South Texas regions are rice hulls and crop residues.
Source: Virtus Energy
On farmlands across Texas, crop residues (stalks and leaves) are usually left in the field after harvesting. A large portion of these wastes could be collected and converted to renewable electricity, fuels and biomass-based products, leaving the remaining residues to protect against soil erosion.
The map at right shows the distribution of various biomass resources throughout Texas. Agricultural materials include:
- harvest residues
- process wastes
- energy crops
The timber industry provides:
- logging residues
- mill residues
- woody energy crops
Urban biomass resources include:
- municipal solid waste
- landfill gas
- used cooking oils
Resources by Region
Upper East and Southeast Texas: Forest Residues and Energy Crops
Timber is one of Texas’ most valuable agricultural commodities, representing 35 percent of East Texas’ agricultural income. Harvested forest biomass such as sawdust, bark and wood chips from saw mills and pulp mills are currently being used in East Texas to generate steam and electricity for local use, or occasionally for resale to the grid. Recycling these wood residues diverts waste from landfills while it reduces reliance on fossil fuels and offsets greenhouse gas emissions by substituting renewable biomass-based carbon dioxide for that emitted by fossil fuels.
Texas A&M’s Texas Cooperative Extension expert, Dr. Eric Taylor, says that when forests are harvested, there are approximately 3.5 million tons of woody biomass scraps left over. Though the technology exists to convert these leftovers to fuel, there are no biorefiners located in East Texas. Dr. Taylor is hopeful that further research and education will create the interest and resources needed to make use of these valuable, unused resources. Woody biomass an be converted into automotive fuel, “green-diesel’ or used to power steam boilers for electricity production.
Forest mills are the largest biomass energy users in the nation, generating more than half of their large energy requirements on site through highly efficient co-generation processes using biomass fuels derived from wood waste products. Forestry residues include logging residues, rough, rotten dead wood and excess small pole trees. Biomass is used in the pulp and paper mills for industrial heat and steam production. Electricity is generated using residues of the wood processing mills and municipal solid waste.
East Texas is also a prime area for the cultivation of woody energy crops, which can be grown specifically for fuel feedstocks or for conversion to biofuels. Short rotation woody crops, like hybrid poplar (cottonwoods) and willow, grow rapidly and can reach 15-25 feet in height after only three years.
Federal funds have been allocated for the study of cellulosic (plant fiber) biomass produced from hybrid poplars and hybrid willows, which are ideal candidates for cellulosic ethanol processing.
Texas High Plains: Sorghum, Canola, Manure
Regional Map of Texas
Texas offers a wide variety of biomass resources in diverse agricultural regions.
Source: Texas Comptroller of Public Accounts
The High Plains cover all but the southeastern third of the Texas Panhandle, 3,000-4,000 feet above sea level. The climate is very dry, making this highly productive agricultural area dependent on irrigation water mined from the Ogllala aquifer. Without irrigation, the nature of agriculture in this region would change significantly. The subterranean Ogallala Aquifer spans almost the entire area underneath very well-drained soils that cover approximately 8 million acres of flat, intensively-cultivated land, where cotton, sorghum and wheat are the predominant crops.
Almost half of the state’s corn is grown in the Northwest Panhandle. But since corn is very sensitive to heat, sorghum is a better alternative. It is also more drought resistant than corn. Sorghum can be used alone as an ethanol feedstock, but most often in Texas it is added to corn in the ethanol refining process. Canola (rapeseed) is currently being considered as a possible biodiesel energy crop for the Panhandle.
The Texas Panhandle is also cattle country, home to some of the largest cattle herds in the world. In the race to produce more ethanol, some producers are looking on feedstock and dairy cow grounds for renewable fuel. The city of Hereford’s new ethanol plant has generated a great deal of interest with its method of using one renewable fuel (manure) to fuel another renewable fuel (ethanol).
Gulf Coast and Rio Grande Delta Lands: Sugarcane and Switchgrass
When Stephen F. Austin traveled to Texas in the 1820s to establish a colony, he looked for the best land to raise Sugarcane. He discovered it near the coastal plains of the Brazos and Colorado Rivers, the fertile alluvial soils of the Gulf Coast Plain. There he settled, and sugarcane became one of the staples of his “colony of 300 families.”
Texas is the fourth largest sugarcane growing state, with most of the cane concentrated in the Lower Rio Grande Valley in the South Texas region. Federal and private groups are studying sugarcane for it use as feedstock in ethanol production. Switchgrass, a tall native grass proposed as an energy crop by DOE, can flourish in these regions as well.
Northwest Texas and Central Texas: Mesquite to Ethanol
SECO contracted with Texas A&M University for work on a study designed to develop a viable mesquite biomass industry in Northwest Texas and to determine the technical, economic and ecological feasibility of harvesting mesquite for use as a renewable biomass in this region. The 2007 report is called “Economical Supply of Mesquite Biomass for Energy Uses” (PDF 987 kB). A summary called “From Campfire to Gas Tank” is also available.
A familiar sight, the dense mesquite-covered mid-section of Texas could provide fuel for about 400 small ethanol plants, according to Texas Agricultural Experiment Station researchers.
Photo courtesy of Texas A&M Agricultural Experiment Station
Rural West Central Texas is another region that has potential for the mesquite biomass industry. According to Jim Ansley, Texas A&M Agricultural Experiment Station rangeland researcher, the prime area to harvest mesquite is the middle third of the state: a band bordered on the west by a line from Childress to Del Rio and on the east from Decatur to Austin. Further research will determine the feasibility of developing a bio-energy industry in rural West Central Texas.
Capital and Central Texas Corn Belt: Ethanol
The Texas “corn belt” is the 10-county area that runs from Brazos County to the east to McLennan County to the north and Travis County to the south produces much of the state’s corn. Milo, a small drought-resistant sorghum which has similar characteristics as corn, also grows well in this area. Texas A&M Extension agronomist Juerg Blumenthal is currently working on breeding sorghum to be used for bioenergy production in Central and East Texas. Several ethanol plants are being planned for Central Texas. With the increased demand for biofuels, the price of grain and the demand for corn and grain sorghum are increasing as well. Texas grain producers are now looking at expanding markets for their investments.