Corn Stover Production Research Articles

Economic Analysis of Utilization of Corn Stover for Bioenergy Production: Towards Diversifying Income Opportunities for Small Farmers

Bioenergy production from plant wastes such as corn stover has the potential to improve energy security and mitigate climate change in the United States. However, there is a limited understanding of its utilization and economic potentials for bioenergy production. The overall objective of the study was to estimate the economic profitability of utilizing corn stover for different ventures after harvesting corn, which includes: 1) corn stover production, 2) ethanol production, and 3) electricity generation through on-farm gasifiers. The data for this study was based on secondary data from various sources. The benefit-cost model was applied for the analysis. Investment evaluation criteria include annualized net return from corn stover, ethanol, and electricity generation. Results show that under current conversion rate, the net return from marketing corn stover ranges from $80.61/kg to $394.11/kg, while the net return from ethanol production ranges from $-104.91/ha to $848.96/ha of corn stover under varying price and yield scenarios. Also, under the government subsidy scheme that covers 25% of equipment costs, there is an investment opportunity for on-farm gasifier with an NPV of $4,329.29. The findings of the study show the potential for using corn stover for bioenergy production since it showed a positive net return. Also, the production of ethanol from corn stover is not only economically feasible but also socially acceptable since it does not compete with food production, and serves as a means of income diversification for corn farmers. Keywords: Corn stover, plant waste, biofuel, ethanol, benefit-cost, gasifier.

Improvement of Plant Growth and Production of Waxy Corn with Organic-NP Enriched Manure and Inorganic Fertilizer in Sragen District of Central Java Indonesia

Organic and inorganic fertilizer are important for crop productivity. Waxy corn (Zea mays ceratina L) is used under crop-livestock system (CLS) in Indonesia. The characterized of CLS is crop yield for food, stover and corn-husk for livestock feed, cattle dung for manure as organic fertilizer. The quality of manure could be enhanced by adding organic-N (Gliricidea sepium) and organic-P (rock phosphate, guano) at the initial fermentation process that was called manure plus. Present study investigated the effects of organic-NP enriched manure application on plant growth and waxy corn production, stover and corn-husk production in vertisol soil Sragen District, Central Java. The experiment was conducted using a randomized complete block design with seven treatments and four replicates, T1 (inorganic-NPK), T2 (manure), T3 (manure+RP), T4 (manure+guano), T5 (manure + legume), T6 (manure+ RP+legume), and T7 (manure+guano+legume). The results showed that plant height and waxy corn production non-significantly affected by the treatment. Fresh waxy corn stover production and fresh corn-husk production significantly affected by the treatments. Manure plus resulted in similar on fresh waxy corn stover production and fresh corn-husk production compared to inorganic-NP fertilizer. It was concluded that organic-NP enriched manure replaces NPK as inorganic fertilizer.

Field-to-farm gate greenhouse gas emissions from corn stover production in the Midwestern U.S.

Measured field data were used to compare two allocation methods on life cycle greenhouse gas emissions from corn (Zea mays L.) stover production in the Midwest U.S. We used publicly-available crop yield, nitrogen fertilizer, and direct soil nitrous oxide emissions data from the USDA-ARS Resilient Economic Agricultural Practices research program. Field data were aggregated from 9 locations across 26 site-years for 3 stover harvest rates (no removal; moderate removal – 3.1 Mg ha−1; high removal – 7.2 Mg ha−1) and 2 tillage practices (conventional; reduced/no-till). Net carbon uptake by crops was computed from measured plant carbon content. Monte Carlo simulations sampled input distributions to assess variability in farm-to-gate GHG emissions. The base analysis assumed no change in soil organic carbon stocks. In all cases, net CO2 uptake during crop growth and soil-respired CO2 dominated system emissions. Emissions were most sensitive to co-product accounting method, with system expansion emissions ∼15% lower than mass allocation. Regardless of accounting method, lowest emissions occurred for a moderate removal rate under reduced/no-till management. The absence of correlations between N fertilization rate and stover removal rate or soil N2O emissions in this study challenges the use of such assumptions typically employed in life cycle assessments Storage of all carbon retained on the field as SOC could reduce emissions by an additional 15%. Our results highlight how variability in GHG emissions due to location and weather can overshadow the impact of farm management practices on field-to-farm gate emissions.

A Watershed Level Economic Analysis of Cellulosic Biofuel Feedstock Production with Consideration of Water Quality

<p>National policy supports the production of renewable energy from cellulosic feedstocks such as corn stover and switchgrass. These feedstocks have contrasting impacts on water quality. In this study, the regional supply response for cellulosic biofuel from these two feedstocks is estimated for the Le Sueur Watershed in South-Central Minnesota. The impacts of the resulting agricultural production activities on water quality in this northern corn belt watershed are also estimated. The Le Sueur River is a tributary of the Minnesota River, which in turn feeds into the Mississippi. The analysis is conducted with a multi-region, endogenous supply, mathematical programming model of the agriculture sector in the watershed. A unique aspect of the analysis is the spatial detail used in the production model. Results from a previous simulation analysis conducted with the Soil Water Assessment Tool (SWAT) model are used in the economic model to simulate the effects of the feedstock supply response on water quality in the Le Sueur. Sediment and nutrient losses from corn stover production make switchgrass more promising on environmental grounds, but the relatively high cost of production causes switchgrass to cover only a small part of crop land if farmers have unrestricted choice about how to supply cellulosic feedstocks.</p>

The Effects of Hybrid Relative Maturity on Corn Stover for Ethanol Production and Biomass Composition

Full‐season corn (Zea mays L.) hybrids take advantage of more of the growing season than shorter‐season hybrids often leading to greater grain and biomass yield. Many agronomic experiments aimed at corn stover production have been performed at forage harvest rather than later when stover is normally harvested for biofuel measurements. The objective of this research was to evaluate the influence of hybrid relative maturity (days RM) on stover ethanol production, ruminant digestibility, and biomass composition. Hybrids selected were high‐yielding commercial grain hybrids grown throughout Wisconsin and ranged from 85 to 115 d RM in 10 d RM increments during 2009, and in 5 d RM increments during 2010. Hybrids were harvested at physiological maturity or after a killing frost. Overall, stover and theoretical ethanol yields increased as RM increased at a linear rate of 0.211 Mg ha−1 RM−1 and 67.1 L ha−1 RM−1. Stover nutritional and biomass composition improved as RM increased, but yield variability was greater than nutritional and biomass compositional variability. Increasing ethanol yields will likely occur by increasing stover yields rather than by altering stover composition. Therefore, until price premiums for stover composition are made available to farmers for ethanol production, the adoption of full‐season or longer maturing hybrids should be implemented for increased stover and ethanol yields.

Elimination of gibberellin from Kappaphycus alvarezii seaweed sap foliar spray enhances corn stover production without compromising the grain yield advantage

Sustainable intensification of agricultural productivity is a global challenge. The sap of the commercially important red seaweed, Kappaphycus alvarezii, has been of interest in this regard, and its application as foliar spray has had a profound impact on the yields of many crops. It has been shown to contain indole acetic acid, kinetin, zeatin and gibberellic acid (GA3) but no study is yet reported on the interactions among these constituents, if any. In the present study, selective solvent extraction was undertaken to obtain GA3-free and indole acetic acid-free sap compositions. Another composition was prepared by autoclaving the sap which resulted in degradation of all the above growth hormones. The sap variants, along with water spray (control) and pristine sap, were applied on Zea mays as foliar spray over three consecutive seasons in dilute form. The four sap treatments were at par with one another—and significantly superior to control treatment—in so far as grain yield and quality were concerned. Pristine sap was subsequently shown to also contain choline and glycine betaine, and these were detected in similar amounts in all the sap variants, apparently indicating their profound influence on grain yield. Another important observation was that GA3-free sap led to heightened photosynthetic activity which translated into 26 % increase in corn stover yield compared to pristine sap. This is hypothesized to be on account of prevention of negative interactions between GA3 and other hormones. The study constitutes the first report of enhancement of performance of a natural seaweed plant stimulant towards increasing plant growth through simplification of its composition.

Life cycle assessment of corn stover production for cellulosic ethanol in Quebec

Whitman, T., Yanni, S.F. and Whalen, J.K. 2011.Life cycle assessment of corn stover production for cellulosic ethanol in Quebec. Can. J. Soil Sci.91: 997–1012. The province of Quebec has a target of 5% ethanol (EtOH) content in fuel by 2012, which means the province will require about 400 million L of ethanol per year based on current consumption. Current research is focused on “second generation biofuels” such as cellulosic EtOH, which can be produced from agricultural by-products like corn stover. A life cycle assessment (LCA) evaluates the “cradle to gate” impact of corn stover feedstock production for cellulosic EtOH production in three corn-producing regions in Quebec for two impact categories: energy and greenhouse gas (GHG) impacts. The modelled system boundaries include in-field processes: corn stover production, collection, transport, soil organic carbon (SOC) loss, and N2O emissions, as well as background processes: herbicide, fertilizer, seed, and fuel production and transport. Sensitivity analyses vary the percentage of corn stover collected, contrast a multiple-pass with a one-pass stover-grain collection system, and compare mass, economic and system expansion allocation methods. Total energy impact is 931–1442 MJ t−1 dry stover collected under 15% stover collection, with stover harvest, transport, and field operationscontributing most strongly to the total impact. Total GHG emissions from corn stover production and transport of stover to the ethanol facility are320–488kg CO2e t−1 dry stover under 15% stover collection, with SOC loss, N2O emissions, and stover harvest contributing the most to the total impact. Sensitivity analysis reveals that the energy and GHG impacts of stover production are strongly influenced by the mass of stover collected, the use of a one-pass system, and the choice of allocation methods. Scaling-up results from the modelled system suggest that 100% of Quebec's EtOH targets could technically be supplied using corn stover feedstock, but this may come at the expense of GHG emissions and soil health.

Optimal Corn Stover Logistics for Biofuel Production: A Case in Minnesota

Logistics management is one of the key hurdles for using corn stover as a feedstock for ethanol production. This article presents a model and its application to compare the costs and CO2 emissions of three corn stover transportation options in the state of Minnesota: truck, rail, and pipeline systems. The corn stover production potential for 53 corn-producing counties in Minnesota is mapped, and potential corn stover storage facilities are located along the railroad system based on regional corn stover production potential. An optimization model was constructed and populated to minimize transportation needs between the storage locations and potential conversion facilities. Because feedstock transportation distance and associated CO2 emissions depend on the number of biorefineries, we varied the number from 1 to 215 and identified optimal locations sequentially at the minimum transportation distance between storage locations and a given number of biorefineries. Using the minimum-distance biorefinery locations identified for each given number of biorefineries, the CO2 emissions associated with corn stover transportation and the total costs were calculated. The results show that pipeline transportation provides the least-cost option, while rail transportation provides the least-CO2 emissions option. In addition, optimal plant capacity was calculated to be about 450 million liters per year (MLY) regardless of the transportation option, so that five becomes the ideal number of biorefineries in Minnesota. Sensitivity analysis on the major assumptions and parameters was performed, and its implications in interpreting the results are discussed.

Energy and Greenhouse Gas Profiles of Polyhydroxybutyrates Derived from Corn Grain: A Life Cycle Perspective

Polyhydroxybutyrates (PHB) are well-known biopolymers derived from sugars orvegetable oils. Cradle-to-gate environmental performance of PHB derived from corn grain is evaluated through life cycle assessment (LCA), particularly nonrenewable energy consumption and greenhouse gas emissions. Site-specific process information on the corn wet milling and PHB fermentation and recovery processes was obtained from Telles. Most of energy used in the corn wet milling and PHB fermentation and recovery processes is generated in a cogeneration power plant in which corn stover, assumed to be representative of a variety of biomass sources that could be used, is burned to generate electricity and steam. County level agricultural information is used in estimating the environmental burdens associated with both corn grain and corn stover production. Results show that PHB derived from corn grain offers environmental advantages over petroleum-derived polymers in terms of nonrenewable energy consumption and greenhouse gas emissions. Furthermore, PHB provides greenhouse gas credits, and thus PHB use reduces greenhouse gas emissions compared to petroleum-derived polymers. Corn cultivation is one of the environmentally sensitive areas in the PHB production system. More sustainable practices in corn cultivation (e.g., using no-tillage and winter cover crops) could reduce the environmental impacts of PHB by up to 72%.