Permanent URI for this collection
This collection contains publications related to the FEWtures project, addressing food, water, and energy futures by evaluating coordination of renewable, variable energy with agricultural needs.
Browse
Recent Submissions
Publication Activating dinitrogen for chemical looping ammonia Synthesis: Mn nitride layer growth modeling(Chemical Engineering Science, 2022-04-28) Aframehr, Wrya Mohammadi; Pfromm, Peter H.The earth-abundant transition metal manganese (Mn) has been shown to activate dinitrogen (N2) and store nitrogen (N) as nitride for subsequent chemical reaction, for example, to produce ammonia (NH3). Chemical looping ammonia synthesis (CLAS) is a practical way to use Mn nitride by contacting nitride with gaseous hydrogen (H2) to produce ammonia (NH3). Here, the dynamic process of N atoms penetrating into solid Mn has been investigated. Nitride layer growth was modeled to quantitate and predict the storage of activated N in Mn towards designing CLAS systems. The N diffusion coefficient (DN) and reaction rate constant K for the first-order nitridation reaction were estimated at 6.2 ± 5.5 × 10-11 m2/s and 4.1 ± 3.5 × 10-4 1/s, respectively, at atmospheric pressure and 700 °C. Assuming spherical particles of Mn with a diameter of < 10 μm, about 56.8 metric tons of Mn is sufficient to produce a metric ton of NH3 per day using CLAS.Publication Activating dinitrogen for chemical looping ammonia synthesis: nitridation of manganese(Journal of Materials Science, 2021-04-23) Aframehr, Wrya Mohammadi; Pfromm, Peter H.The earth-abundant transition metal manganese (Mn) has been shown to be useful to activate dinitrogen at atmospheric pressure and elevated temperature by forming bulk Mn nitrides. Mn nitrides could then be used, for example, for ammonia (NH3) synthesis in a chemical looping process by contacting nitride with gaseous hydrogen (H2). Here, we present an investigation of the morphology and local time-dependent composition of micrometer-scale Mn plates during nitridation in dinitrogen (N2) near atmospheric pressure at 700 °C. The main motivation was to obtain design data for chemical looping synthesis of NH3 and to add to the somewhat sparse literature on nitridation of Mn. The morphology and elemental compositional variation of the nitrided specimens were studied with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), wide angle X-ray diffraction (WAXD), and mass balances. Three possible nitrogen (N) populations that may govern the Mn nitridation and later NH3 synthesis are identified. After four hours of nitridation, the N weight gain was found to be 9.4 ± 0.7 kgN to nMn−1 for the plates used here, resulting in a nitridation depth of 83 ± 8 μm.Publication Relating agriculture, energy, and water decisions to farm incomes and climate projections using two freeware programs, FEWCalc and DSSAT(Agricultural Systems, 2021-10) Phetheet, Jirapat; Hill, Mary C.; Barron, Robert W.; Gray, Benjamin Jerome; Wu, Hongyu; Amanor-Boadu, Vincent; Heger, Wade; Kisekka, Isaya; Golden, Bill; Rossi, Matthew W.Context: The larger scale perspective of Integrated Assessment (IA) and smaller scale perspective of Impacts, Adaptation, and Vulnerability (IAV) need to be bridged to design long-term solutions to agricultural problems that threaten agricultural production, rural economic viability, and global food supplies. FEWCalc (Food-Energy-Water Calculator) is a new freeware, agent-based model with the novel ability to project farm incomes based on crop selection, irrigation practices, groundwater availability, renewable energy investment, and historical and projected environmental conditions. FEWCalc is used to analyze the interrelated food, energy, water, and climate systems of Finney County, Kansas to evaluate consequences of choices currently available to farmers and resource managers. Objective: This article aims to evaluate local farmer choices of crops and renewable energy investment in the face of water resource limitations and global climate change. Metrics of the analysis include agricultural and renewable-energy production, farm income, and water availability and quality. The intended audience includes farmers, resource managers, and scientists focusing on food, energy, and water systems. Methods: Data derived from publicly available sources are used to support user-specified FEWCalc input values. DSSAT (Decision Support System for Agrotechnology Transfer) with added arid-region dynamics is used to obtain simulated crop production and irrigation water demand for FEWCalc. Here, FEWCalc is used to simulate agricultural and energy production and farm income based on continuation of recent ranges of crop prices, farm expenses, and crop insurance; continuation of recent renewable-energy economics and government incentives; one of four climate scenarios, including General Circulation Model projections for Representative Concentration Pathway 8.5; and groundwater-supported irrigation and its limitations. Results and Conclusions: A 50-year (2018-2067) climate and groundwater availability projection process indicates possible trends of future crop yield, water utility, and farm income. The simulation during more wet years produces high crop production and slower depletion of groundwater, as expected. However, surprisingly, the simulations suggest that only the Drier Future scenario is commercially profitable, and this is because of reduced expenses for dryland farming. Although simulated income losses due to low crop production are ameliorated by the energy sector income and crop insurance, the simulation under climate change still produces the worst annual total income. Significance: FEWCalc addresses scientific, communication, and educational gaps between global- and local-scale FEW research communities and local stakeholders, affected by food, energy, water systems and their interactions by relating near-term choices to near- and long-term consequences. This analysis is needed to craft a more advantageous future.Publication Consequences of climate change on food-energy-water systems in arid regions without agricultural adaptation, analyzed using FEWCalc and DSSAT(Resources, Conservation and Recycling, 2021-05) Phetheet, Jirapat; Hill, Mary C.; Barron, Robert W.; Rossi, Matthew W.; Amanor-Boadu, Vincent; Wu, Hongyu; Kisekka, IsayaEffects of a changing climate on agricultural system productivity are poorly understood, and likely to be met with as yet undefined agricultural adaptations by farmers and associated business and governmental entities. The continued vitality of agricultural systems depends on economic conditions that support farmers’ livelihoods. Exploring the long-term effects of adaptations requires modeling agricultural and economic conditions to engage stakeholders upon whom the burden of any adaptation will rest. Here, we use a new freeware model FEWCalc (Food-Energy-Water Calculator) to project farm incomes based on climate, crop selection, irrigation practices, water availability, and economic adaptation of adding renewable energy production. Thus, FEWCalc addresses United Nations Global Sustainability Goals No Hunger and Affordable and Clean Energy. Here, future climate scenario impacts on crop production and farm incomes are simulated when current agricultural practices continue so that no agricultural adaptations are enabled. The model Decision Support System for Agrotechnology Transfer (DSSAT) with added arid-region dynamics is used to simulate agricultural dynamics. Demonstrations at a site in the midwest USA with 2008–2017 historical data and two 2018–2098 RCP climate scenarios provide an initial quantification of increased agricultural challenges under climate change, such as reduced crop yields and increased financial losses. Results show how this finding is largely driven by increasing temperatures and changed distribution of precipitation throughout the year. Without effective technological advances and operational and policy changes, the simulations show how rural areas could increasingly depend economically on local renewable energy, while agricultural production from arid regions declines by 50% or more.Publication Chemical Looping of Manganese to Synthesize Ammonia at Atmospheric Pressure: Sodium as Promoter(Chemical Engineering & Technology, 2020-08-10) Aframehr, Wrya Mohammadi; Huang, Chaoran; Pfromm, Peter H.Affordable synthetic ammonia (NH3) enables the production of nearly half of the food we eat and is emerging as a renewable energy carrier. Sodium-promoted chemical looping NH3 synthesis at atmospheric pressure using manganese (Mn) is here demonstrated. The looping process may be advantageous when inexpensive renewable hydrogen from electrolysis is available. Avoiding the high pressure of the Haber-Bosch process by chemical looping using earth-abundant materials may reduce capital cost, facilitate intermittent operation, and allow operation in geographic areas where infrastructure is less sophisticated. At this early stage, the data suggest that 0.28 m3 of a 50 % porosity solid Mn bed may suffice to produce 100 kg NH3 per day by chemical looping, with abundant opportunities for improvement.Publication Resilience and technological diversity in smart homes(Journal of Ambient Intelligence and Humanized Computing, 2020) Modarresi, Amir; Symons, JohnThis article introduces our abstract modeling strategy to represent the general features and topology of the kinds of integrated and technologically diverse networks that feature in IoT systems. We begin with smart home networks. We generate instances of our model and analyze their graph-theoretic properties with an emphasis on the resilience of critical services and connections to the Global Internet. In addition to considering the network connectivity graph of nodes and links in the model, we explain our technology interdependence graph techniques. Technology interdependence graphs allow us to illuminate critical interactions in multi-technology systems such as smart homes. Using relatively simple examples we show how our approach permits the exploration of the resilience properties of various instances of smart systems involving complex technological interdependency. We describe a practical way of approaching the graphs of systems with a wide variety of integrated technologies and we discuss properties such as connectedness and other metrics. This approach can serve as the basis for tackling the challenge of designing resilient IoT-based smart-cities from the point of view of network topologies. We also study smart home resilience through path redundancy and heterogeneity of network technologies with graph centrality metrics.Publication Intelligent Systems for Geosciences: An Essential Research Agenda(Communications of the ACM, 2019-01) Gil, Yolanda; Pierce, Suzanne A.; Babaie, Hassan; Banerjee, Arindam; Borne, Kirk; Bust, Gary; Cheatham, Michelle; Ebert-Uphoff, Imme; Gomes, Carla; Hill, Mary C.; Horel, John; Hsu, Leslie; Kinter, Jim; Knoblock, Craig; Krum, David; Kumar, Vipin; Lermusiaux, Pierre; Liu, Yan; North, Chris; Pankratius, Victor; Peters, Shanan; Plale, Beth; Pope, Allen; Ravela, Sai; Restrepo, Juan; Ridley, Aaron; Samet, Hanan; Shekhar, Shashi; Skinner, Katie; Smyth, Padhraic; Tikoff, Basil; Yarmey, Lynn; Zhang, JiaA research agenda for intelligent systems that will result in fundamental new capabilities for understanding the Earth system. Many aspects of geosciences pose novel problems for intelligent systems research. Geoscience data is challenging because it tends to be uncertain, intermittent, sparse, multiresolution, and multiscale. Geosciences processes and objects often have amorphous spatiotemporal boundaries. The lack of ground truth makes model evaluation, testing, and comparison difficult. Overcoming these challenges requires breakthroughs that would significantly transform intelligent systems, while greatly benefitting the geosciences in turn.Publication A wedge or a weight? Critically examining nuclear power’s viability as a low carbon energy source from an intergenerational perspective(Energy Research & Social Science, 2019-04) Barron, Robert W.; Hill, Mary C.Some integrated assessment studies of climate change have concluded that nuclear energy has a large potential impact on carbon abatement costs. However, these studies have often modeled the cost of nuclear waste management very simply or neglected it entirely. Common difficulties with existing studies include the use of simplistic nuclear waste management cost models and implicitly minimizing costs in the distant future by using discount rates that are arguably inappropriate for intergenerational cost-benefit analysis. These difficulties lead to results that may underestimate the cost of nuclear waste management – and therefore overestimate the value of nuclear energy as a low carbon energy technology. Here, we consider how a more realistic treatment of the nuclear waste disposal problem than has been used in previous studies could affect the viability of nuclear power in the context of integrated assessments of climate change. We construct a generic nuclear waste management cost model to develop cost estimates for nuclear waste management based on current policy, practice, and cost estimates for storage and disposal technologies. Our cost estimates are discounted using conventional constant exponential discounting as and a declining discount rate scheme. Results suggest that the optimism reflected in previous works is fragile: More realistic nuclear waste management cost models and uncertainty-appropriate intergenerational discount rates produce many more scenarios in which nuclear waste management costs are higher than previously assumed. As a consequence, nuclear energy’s economic attractiveness as a low carbon energy option is appears to be lower than earlier works suggested.Publication Beyond fossil fuel–driven nitrogen transformations(Science, 2018-05-25) Chen, Jingguang G.; Crooks, Richard M.; Seefeldt, Lance C.; Bren, Kara L.; Bullock, R. Morris; Darensbourg, Marcetta Y.; Holland, Patrick L.; Hoffman, Brian; Janik, Michael J.; Jones, Anne K.; Kanatzidis, Mercouri G.; King, Paul; Lancaster, Kyle M.; Lymar, Sergei V.; Pfromm, Peter H.; Schneider, William F.; Schrock, Richard R.How much carbon does it take to make nitric acid? The counterintuitive answer nowadays is quite a lot. Nitric acid is manufactured by ammonia oxidation, and all the hydrogen to make ammonia via the Haber-Bosch process comes from methane. That's without even accounting for the fossil fuels burned to power the process. Chen et al. review research prospects for more sustainable routes to nitrogen commodity chemicals, considering developments in enzymatic, homogeneous, and heterogeneous catalysis, as well as electrochemical, photochemical, and plasma-based approaches.Publication Towards sustainable agriculture: Fossil-free ammonia(Journal of Renewable and Sustainable Energy, 2016-12-28) Pfromm, Peter H.About 40% of our food would not exist without synthetic ammonia (NH3) for fertilization. Yet, NH3 production is energy intensive. About 2% of the world's commercial energy is consumed as fossil fuels for NH3 synthesis based on the century-old Haber-Bosch (H.-B.) process. The state of the art and the opportunities for reducing the fossil energy footprint of industrial H.-B. NH3 synthesis are discussed. It is shown that even a hypothetical utterly revolutionary H.-B. catalyst could not significantly reduce the energy demand of H.-B. NH3 as this is governed by hydrogen production. Renewable energy-enabled, fossil-free NH3 synthesis is then evaluated based on the exceptional and continuing cost decline of renewable electricity. H.-B. syngas (H2, N2) is assumed to be produced by electrolysis and cryogenic air separation and then supplied to an existing H.-B. synthesis loop. Fossil-free NH3 could be produced for energy costs of about $232 per tonne NH3 without claiming any economic benefits for the avoidance of about 1.5 tonnes of CO2 released per tonne NH3 compared to the most efficient H.-B. implementations. Research into alternatives to the H.-B. process might be best targeted at emerging markets with currently little NH3 synthesis capacity but significant future population growth in markets such as Africa. Reduced capital intensity, good scale-down economics, tolerance for process upsets and contamination, and intermittent operability are some desirable characteristics of NH3 synthesis in less developed markets and for stranded resources. Processes that are fundamentally different from H.-B. may come to the fore under these specific boundary conditions.Publication Legitimate to whom? The challenge of audience diversity and new venture legitimacy(Journal of Business Venturing, 2017-01) Fisher, Greg; Kuratko, Donald F.; Bloodgood, James M.; Hornsby, Jeffrey S.We examine how entrepreneurs manage new venture legitimacy judgments across diverse audiences, so as to appear legitimate to the different audience groups that provide much needed financial resources for venture survival and growth. To do so, we first identify and describe the different mechanisms by which entrepreneurs can establish new venture legitimacy across diverse audiences. We then account for the institutional logics that characterize different new venture audience groups, and use this as a basis for uncovering how and why the legitimacy criteria for a new technology venture may vary depending on the audience. We then consider how leaders of entrepreneurial ventures may use framing as a means to manage legitimacy judgments across various audiences, and thereby improve their chances of accessing critical financial resources for venture survival and growth.Publication The role of network density and betweenness centrality in diffusing new venture legitimacy: an epidemiological approach(International Entrepreneurship and Management Journal, 2017) Bloodgood, James M.; Hornsby, Jeffrey S.; Rutherford, Matthew; McFarland, Richard G.To survive and grow, new ventures must establish initial legitimacy, and subsequently diffuse this legitimacy through a given population. While the notion of initial legitimacy has received substantial attention in the recent literature, diffusion has not. This work endeavors to outline the legitimacy diffusion process via drawing parallels with the field of epidemiology. Ultimately, to effectively diffuse legitimacy (and grow) a firm must gain positive judgments of appropriateness from members of a given network. Importantly, as with diseases, the characteristics of the network are critical to the diffusion process. A relatively dense network is posited to invoke a normative evaluation process by its members, and can be difficult for new ventures to access, but subsequent diffusion of new venture legitimacy can be rapid. A less dense network, on the other hand, is posited to invoke a pragmatic evaluation process by its members, and is likely easier for new ventures to access initially, but may result in lower levels of new venture legitimacy diffusion in the long run. Theoretical and practical implications are discussed.Publication Regulating the Ogallala: Paradox and Ambiguity in Western Kansas(The Economics of Ecology, Exchange, and Adaptation: Anthropological Explorations, 2016-09-01) Gibson, Jane W.; Gray, Benjamin JeromePurpose: To illuminate the underlying logic of western Kansas farmers’ decisions to irrigate at unsustainable rates and the state’s regulatory policies and practices that enable depletion of the Ogallala aquifer. Methodology/approach: Ethnographic interviewing of 39 western Kansas farmers, state water management personnel, and archival research. Findings: Farmers occupy an ambiguous position as petty capitalists who focus attention on their own farms with seasonal planning horizons, and they hold a view of “good stewardship” that melds economic and noneconomic considerations, and that provides a rationale for unsustainable irrigation practices. The state resolves the contradiction between the finite groundwater resource and ideological commitments to economic growth by devolving responsibility for water management to groundwater users. Research Limitations/Implications: While the small sample size is likely to be representative of the larger pool of irrigators, further research with other farmers representative of the region will be necessary to verify findings. Social implications: Depletion of the Ogallala aquifer contributes to farm consolidation and community decline, and the ecological costs will leave future farmers and remaining communities without the benefits of groundwater. Western Kansas will likely have to revert to a system of dryland farming.Publication Economic feasibility of algal biodiesel under alternative public policies(Renewable Energy, 2014-07) Amanor-Boadu, Vincent; Pfromm, Peter H.; Nelson, RichardThe motivation for this research was to determine the influence of public policies on economic feasibility of producing algal biodiesel in a system that produced all its energy needs internally. To achieve this, a steady-state mass balance/unit operation system was modeled first. Open raceway technology was assumed for the production of algal feedstock, and the residual biomass after oil extraction was assumed fermented to produce ethanol for the transesterification process. The project assumed the production of 50 million gallons of biodiesel per year and using about 14% of the diesel output to supplement internal energy requirements. It sold the remainder biodiesel and ethanol as pure biofuels to maximize the rents from the renewable fuel standards quota system. Assuming a peak daily yield of 500 kg algal biomass (dry basis)/ha, the results show that production of algal biodiesel under the foregoing constraints is only economically feasible with direct and indirect public policy intervention. For example, the renewable fuel standards' tracking RIN (Renewable fuel Identification Number) system provides a treasury-neutral value for biofuel producers as does the reinstatement of the renewable fuel tax credit. Additionally, the capital costs of an integrated system are such that some form of capital cost grant from the government would support the economic feasibility of the algal biodiesel production.Publication Actor–Networks, Farmer Decisions, and Identity(Culture, Agriculture, Food and Environment, 2013) Gray, Benjamin Jerome; Gibson, Jane W.Climate change and industrial agricultural practices pose threats to the future of Kansas agriculture. To inform the debate about sustainable agriculture that must soon occur, we seek to illuminate the factors involved in the decision making of farmers in Kansas. Drawing from Actor–Network Theory, we consider how farmers’ participation in the industrial agricultural network shapes their decisions, defines the types of knowledge and skills that are valued by farmers and others in the network, transforms what it means to be a Kansas grain farmer, and entrenches unsustainable production practices.Publication Solar thermochemical production of ammonia from water, air and sunlight: Thermodynamic and economic analyses(Energy, 2012-06) Michalsky, Ronald; Parman, Bryon J.; Amanor-Boadu, Vincent; Pfromm, Peter H.Ammonia is an important input into agriculture and is used widely as base chemical for the chemical industry. It has recently been proposed as a sustainable transportation fuel and convenient one-way hydrogen carrier. Employing typical meteorological data for Palmdale, CA, solar energy is considered here as an inexpensive and renewable energy alternative in the synthesis of NH3 at ambient pressure and without natural gas. Thermodynamic process analysis shows that a molybdenum-based solar thermochemical NH3 production cycle, conducted at or below 1500 K, combined with solar thermochemical H2 production from water may operate at a net-efficiency ranging from 23 to 30% (lower heating value of NH3 relative to the total energy input). Net present value optimization indicates ecologically and economically sustainable NH3 synthesis at above about 160 tons NH3 per day, dependent primarily on heliostat costs (varied between 90 and 164 dollars/m2), NH3 yields (ranging from 13.9 mol% to stoichiometric conversion of fixed and reduced nitrogen to NH3), and the NH3 sales price. Economically feasible production at an optimum plant capacity near 900 tons NH3 per day is shown at relative conservative technical assumptions and at a reasonable NH3 sales price of about 534 ± 28 dollars per ton NH3.Publication Sustainability of algae derived biodiesel: A mass balance approach(Bioresource Technology, 2011-01) Pfromm, Peter H.; Amanor-Boadu, Vincent; Nelson, RichardA rigorous chemical engineering mass balance/unit operations approach is applied here to bio-diesel from algae mass culture. An equivalent of 50,000,000 gallons per year (0.006002 m3/s) of petroleum-based Number 2 fuel oil (US, diesel for compression–ignition engines, about 0.1% of annual US consumption) from oleaginous algae is the target. Methyl algaeate and ethyl algaeate diesel can according to this analysis conceptually be produced largely in a technologically sustainable way albeit at a lower available diesel yield. About 11 square miles of algae ponds would be needed with optimistic assumptions of 50 g biomass yield per day and m2 pond area. CO2 to foster algae growth should be supplied from a sustainable source such as a biomass-based ethanol production. Reliance on fossil-based CO2 from power plants or fertilizer production renders algae diesel non-sustainable in the long term.Publication Bio-butanol vs. bio-ethanol: A technical and economic assessment for corn and switchgrass fermented by yeast or Clostridium acetobutylicum(Biomass and Bioenergy, 2010-04) Pfromm, Peter H.; Amanor-Boadu, Vincent; Nelson, Richard; Vadlani, Praveen; Madl, RonaldFermentation-derived butanol is a possible alternative to ethanol as a fungible biomass-based liquid transportation fuel. We compare the fermentation-based production of n-butanol vs. ethanol from corn or switchgrass through the liquid fuel yield in terms of the lower heating value (LHV). Industrial scale data on fermentation to n-butanol (ABE fermentation) or ethanol (yeast) establishes a baseline at this time, and puts recent advances in fermentation to butanol in perspective. A dynamic simulation demonstrates the technical, economic and policy implications. The energy yield of n-butanol is about half that of ethanol from corn or switchgrass using current ABE technology. This is a serious disadvantage for n-butanol since feedstock costs are a significant portion of the fuel price. Low yield increases n-butanol's life-cycle greenhouse gas emission for the same amount of LHV compared to ethanol. A given fermenter volume can produce only about one quarter of the LHV as n-butanol per unit time compared to ethanol. This increases capital costs. The sometimes touted advantage of n-butanol being more compatible with existing pipelines is, according to our techno-economic simulations insufficient to alter the conclusion because of the capital costs to connect plants via pipeline.