Mesquite biomass could be feasible for electricity generation things like grass production were factored in. (Texas A&M AgriLife Research photo) Using mesquite biomass for electricity generation may become economically feasible if ecological and agricultural factors are considered, according to a Texas A&M AgriLife Research paper being published in the BioEnergy Research journal.
“Economic Feasibility of Mesquite Biomass for Electricity Production: Projections of the Long-term Sustainability of Two Harvest Options” will appear in the April issue of the journal.
The paper was written by AgriLife Research personnel Dr. Jaesung Cho, postdoctoral associate; Dr. Seong Park, economist; Dr. Jim Ansley, rangeland ecologist; and Dr. Mustafa Mirik, associate research scientist, all in Vernon.
Their study estimated the long-term economic feasibility of mesquite biomass in electricity production under five different harvest scenarios, Park said. They examined variations in rates of standing biomass accumulation and tree density re-establishment after harvest using an above-ground-only or whole-plant harvest option.
Other work by Ansley has shown the heating value of mesquite is nearly equal to low grade coal.
The ecological and agricultural benefits of harvesting mesquite for bioenergy make it a potentially viable alternative to coal, Park said. More traditional income from these lands, such as livestock grazing and hunting, would be enhanced, and mesquite control costs would be reduced.
Current control methods of mesquite include herbicide sprays, mechanical treatments and prescribed fire, Ansley said. Herbicides and mechanical treatments can be costly for landowners. And prescribed fire, the least expensive option, has limited use due to the smoke distribution and higher risk of damage to non-target areas, especially during drought.
Increased grass production would lead directly to increased agricultural income through grazing by cattle, and leaving patches or strips of unharvested mesquite among harvested areas would increase wildlife habitat, he said. Mesquite reduction also could lower soil erosion due to the increased grass cover and increase off-site water yields into rivers and streams.
However, the researchers found some drawbacks to using mesquite as a bioenergy feedstock for electricity production. Re-growth and harvesting costs vary greatly, depending on the harvesting methods, rainfall and soil type. This can disrupt the supply of mesquite biomass for a power plant.