Bioenergy Crops
Bioenergy Crops at the Mountain Horticultural Crops Research Station in Mills River, NC. Dwayne Tate, Research Specialist
North Carolina’s future energy supply will undoubtedly include a diversity of bioenergy crops. To be successful, it’s essential that these crops 1) maximize net energy production per unit area, 2) can be grown on marginal land with minimal inputs, 3) are profitable throughout the value chain, and 4) are sustainable with minimal environmental impacts. As technologies emerge and develop, the competitiveness and profitability of different bioenergy systems and fuelstocks will continue to change. Therefore, it is also ideal to begin development and production of transitional bioenergy crops that will have broad utility and value in diverse markets in both the near and long term. Perennial grasses including cold hardy sugarcanes (Tripidium spp.), miscanthus (Miscanthus spp.), and giant reed (Arundo donax) meet these criteria and are ideal candidates for bioenergy crops.
These perennial grasses are characterized as having broad adaptability, high water and nitrogen use efficiencies, excellent pest resistance, and productive life spans that exceed 15 years. Due to associations with nitrogen-fixing bacteria, many of these plants can achieve high yields with minimal nitrogen fertilizer input and are ideally suited for marginal lands. Total dry biomass yields for some grasses can exceed 20 T/acre (~2800 G ethanol/acre). In addition to being a substitute for fossil fuels, these grasses are perennial with large persistent root systems and can fix more carbon than is harvested (over 3 tons C/acre/year), resulting in positive net carbon sequestration and greater potential for carbon credits. These crops can be used as fuel for heat and electric power generation, for production of fiber composite products, as forage for livestock, and ultimately as a fuelstock for cellulosic ethanol production. Since these crops are largely unimproved there is considerable potential for breeding superior crops.
Researchers at NC State University including Drs. Thomas Ranney and Darren Touchell (Horticultural Science), Dr. Carl Crozier (Soil Science), and Dr. Ratna Sharma-Shivappa (Department of Biological and Agricultural Engineering) are taking an interdisciplinary approach to tailoring these crops to North Carolina. State-wide evaluation trials are underway to evaluate regional adaptability, biomass yields, fertilizer responses, and sustainable production systems. Breeding efforts are focusing on the development of new high-yielding, non-invasive cultivars with regional adaptability and improved cold hardiness. In the lab, research is progressing to optimize and improve cellulosic ethanol bioprocessing, specifically for energy canes. Graduate students Irene Palmer (Horticultural Science), Stephanie Haines (Soil Science), and Anushadevi Panneerselvam (Biological and Agricultural Engineering), are working on breeding, production, and bioprocessing, respectively. Additional support for these projects has come from the Biofuels Center of North Carolina and BP Biofuels.
From field to fuel tanks, these efforts are driving new bioenergy crops to serve North Carolina’s diverse energy and economic needs. For additional information see:
- Haines, S.A., R.J. Gehl, T.G. Ranney, and J.L. Havlin. 2010. Response of Miscanthus xgiganteus to phosphorus and nitrogen fertilizer on low phosphorus soils in North Carolina. Soil Science Society of North Carolina 53rd Annual Meeting. Raleigh, NC. 19-20 January 2010. (poster)
- Sharma-Shivappa, R., A. Panneerselvam, P. Kolar, T. Ranney, and S. Peretti. 2010. Effect of ozonolysis on bioconversion of miscanthus to bioethanol. Annual International Meeting of the American Society for Agricultural and Biological Engineers. (presentation).
- Panneerselvam, A., R. Sharma – Shivappa1, P. Kolar, T. Ranney, and S. Peretti. 2011. Ozonolysis – A novel pretreatment method to delignify energy canes. Soc. Ind. Microbiology, 33rd Symp. Biotechnol. for Fuels and Chemicals. Seattle, WA.
2-5 May, 2011. (abstract). - Palmer, I.E., R.J. Gehl, T.G. Ranney, D. Touchell, and N. George. 2014. Biomass yield, nitrogen response, and nutrient uptake of perennial bioenergy grasses in North Carolina. Biomass & Bioenergy 63:218-228.
- Haines, S., R. Gehl, J. Havlin, and T.G. Ranney. 2015. Nitrogen and phosphorus fertilizer effects on establishment of giant miscanthus. BioEnergy Res. 8:17-27.
- Palmer, I.E., R.J. Gehl, T.G. Ranney, D. Touchell, and N. George. 2014. Biomass yield, nitrogen response, and nutrient uptake of perennial bioenergy grasses in North Carolina. Biomass & Bioenergy 63:218-228.
- Touchell, D.H., T.G. Ranney, D.R. Panthee, R.J. Gehl, and A. Krings. 2016. Genetic diversity, cytogenetics, and biomass yields among taxa of giant reeds (Arundo species). J. Amer. Soc. Hort. Sci. 141(3):256-263.
- Maren, N.A., D.H. Touchell, T.G. Ranney, H. Ashrafi, M.B. Whitfield, and M. Chinn. 2020. Biomass yields, cytogenetics, fertility, and compositional analyses of novel bioenergy grass hybrids (Tripidium spp.). Global Change Biology Bioenergy. https://doi.org/10.1111/GCBB.12676.
- Touchell, D.H., N.P. Lynch, R. Shekasteband, A.N. Dickey, M.C. Chinn, M. Whitfield, and T.G. Ranney. 2024. Biomass yields, reproductive fertility, compositional analysis, and genetic diversity of newly developed triploid giant miscanthus hybrids. GCB BioEnergy 16(7) https://doi.org/10.1111/gcbb.13174