Drought,ethanol, and livestock

The 2012 drought in the U.S. Midwest resulted in volatile crop prices. With field crops constituting a major input in livestock production, livestock producers sought a waiver to Renewable Fuel Standard biofuel mandates. They believed such a waiver would mitigate crop-price volatility; given crops are major inputs in biofuel production. The U.S. Environmental Protection Agency (EPA) denied the waiver under the belief that the waiver would have minimal if any impact on mitigating price volatility. Employing a VECM, the objective is to investigate if it was prudent for the EPA to reject the waiver. Results generally support EPA's conclusion that the waiver relaxing the biofuel mandate would have minimal impact.     

Providing all global energy with wind,water, and solar power,Part I: Technologies,energy resources,quantities and areas of infrastructure,and materials

Climate change, pollution, and energy insecurity are among the greatest problems of our time. Addressing them requires major changes in our energy infrastructure. Here, we analyze the feasibility of providing worldwide energy for all purposes (electric power, transportation, heating/cooling, etc.) from wind, water, and sunlight (WWS). In Part I, we discuss WWS energy system characteristics, current and future energy demand, availability of WWS resources, numbers of WWS devices, and area and material requirements. In Part II, we address variability, economics, and policy of WWS energy. We estimate that ∼3,800,000 5 MW wind turbines, ∼49,000 300 MW concentrated solar plants, ∼40,000 300 MW solar PV power plants, ∼1.7 billion 3 kW rooftop PV systems, ∼5350 100 MW geothermal power plants, ∼270 new 1300 MW hydroelectric power plants, ∼720,000 0.75 MW wave devices, and ∼490,000 1 MW tidal turbines can power a 2030 WWS world that uses electricity and electrolytic hydrogen for all purposes. Such a WWS infrastructure reduces world power demand by 30% and requires only ∼0.41% and ∼0.59% more of the world's land for footprint and spacing, respectively. We suggest producing all new energy with WWS by 2030 and replacing the pre-existing energy by 2050. Barriers to the plan are primarily social and political, not technological or economic. The energy cost in a WWS world should be similar to that today.     

Providing all global energy with wind,water, and solar power,Part II: Reliability,system and transmission costs,and policies

This is Part II of two papers evaluating the feasibility of providing all energy for all purposes (electric power, transportation, and heating/cooling), everywhere in the world, from wind, water, and the sun (WWS). In Part I, we described the prominent renewable energy plans that have been proposed and discussed the characteristics of WWS energy systems, the global demand for and availability of WWS energy, quantities and areas required for WWS infrastructure, and supplies of critical materials. Here, we discuss methods of addressing the variability of WWS energy to ensure that power supply reliably matches demand (including interconnecting geographically dispersed resources, using hydroelectricity, using demand-response management, storing electric power on site, over-sizing peak generation capacity and producing hydrogen with the excess, storing electric power in vehicle batteries, and forecasting weather to project energy supplies), the economics of WWS generation and transmission, the economics of WWS use in transportation, and policy measures needed to enhance the viability of a WWS system. We find that the cost of energy in a 100% WWS will be similar to the cost today. We conclude that barriers to a 100% conversion to WWS power worldwide are primarily social and political, not technological or even economic.     

Wood preparation, storage, and drying

The research cooperation in this activity has shown a fundamentally different attitude between the participating scientists in the scientific line of procedure considered.

One group proceeds pragmatically. The group has the opinion that drying progress in big chip stacks is determined by so many intercorrelated factors that it is practically impossible to work out mathematical models of the drying progress. Therefore, the group conducts full scale field trials.

Contrary to this attitude a more scientific line of procedure is maintained by other scientists. This line of procedure tries to establish the natural laws which determine drying of comminuted wood fuels. This is done by mathematical modelling and controlled laboratory experiments.

Both types of experiment are described in this paper.     

Hydrogen and ethanol: Production,storage, and transportation

The present paper provides insights into the feasibility of using hydrogen and bioethanol blends as energy carriers in the foreseeable future upon discussions on the advantages and the disadvantages. The comprehensive overviews on the production, storage, and transportation of hydrogen and bioethanol have been made; and the current problems and potential solutions for the three stages have been summarized. Finally, the prospections on hydrogen and bioethanol could be expect optimistically.     

Hydrogen carriers: Production,transmission, decomposition,and storage

Recognizing the potential role of liquid hydrogen carriers in overcoming the inherent limitations in transporting and storing gaseous and liquid hydrogen, a complete production and use scenario is postulated and analyzed for perspective one-way and two-way carriers. The carriers, methanol, ammonia and toluene/MCH (methylcyclohexane), are produced at commercially viable scales in a central location, transmitted by rail or pipelines for 2000 miles, and decomposed near city gates to generate fuel-cell quality hydrogen for distribution to refueling stations. In terms of the levelized cost of H₂ distributed to the stations, methanol is less expensive to produce ($1.22/kg-H₂) than MCH ($1.35/kg-H₂) or ammonia ($2.20/kg-H₂). Levelized train transmission cost is smaller for methanol ($0.63/kg-H₂) than ammonia ($1.29/kg-H₂) or toluene/MCH system ($2.07/kg-H₂). Levelized decomposition cost is smaller for ammonia ($0.30–1.06/kg-H₂) than MCH ($0.54–1.22/kg-H₂) or methanol ($0.43–1.12/kg-H₂). Over the complete range of demand investigated, 10–350 tpd-H₂, the levelized cost of H₂ distributed to stations is aligned as methanol « ammonia ~ MCH. With pipelines at much larger scale, 6000 tpd-H₂, the levelized cost decreases by ~1 $/kg-H₂ for ammonia and MCH and much less for methanol. Methanol is a particularly attractive low-risk carrier in the transition phase with lower than 50-tpd H₂ demand.     

Household energy use,energy efficiency,emissions, and behaviors

Energy and greenhouse gas (GHG) emissions generally aim to (i) reduce energy use and hence emissions, (ii) steer consumers away from fossil fuels and/or electricity generated from fossil fuels, and (iii) align demand and supply, making sure that the existing infrastructure can handle times of high demand. Policies thus include a variety of pricing schemes, taxes on energy inputs, energy efficiency standards and incentives, and renewables standards and incentives. Ex ante and ex post analyses of their effectiveness thus rely crucially on understanding how consumers respond to pricing schemes, taxes, and other policies. This paper presents an overview of the challenges faced when empirically estimating household energy demand. It describes the difficulties associated with estimating the price elasticity of demand, discussing behavioral responses that may make consumers relatively insensitive to price changes or taxes. It also surveys empirical evidence about non-price policies, such as clearer information or real-time feedback about energy use, and appeal to norms. The paper concludes discussing evidence about the rebound effect, the energy efficiency gap, and how suppliers respond to a variety of policies.     

Energy,industry and politics: Energy,vested interests,and long-term economic growth and development

The article seeks to explicate a link between energy and long-term economic growth and development. While in many ways intuitive, attempts at sketching theoretical frameworks explicating this link have been few and simplistic, typically limited to technology and economics. This article emphasizes the importance of politics as well, fostering a symbiosis between the dominant industries of a historical epoch and the energy system that enabled them to flourish. The framework combines Joseph Schumpeter and Mancur Olson, emphasizing 1) the importance of structural economic change for long-term growth and development and 2) vested interests. The framework yields one theoretical proposition: In order to rise, states must prevent vested interests from blocking structural change. States that are unable to do this will get locked into yesterday's technologies, industries and energy systems, effectively consigning themselves to stagnation and decline. A brief empirical section provides historical data from 6 historical epochs (including present-day renewables) over a period of 250 years to demonstrate the usefulness of the approach. While no exhaustive test, the data suggests that countries that have prevented vested interests from blocking change have been far more successful in fostering a symbiosis between energy and industry than those countries that have not.     

Components,formulations, solutions,evaluation, and application of comprehensive combustion models

Development and application of comprehensive, multidimensional, computational combustion models are increasing at a significant pace across the world. While once confined to specialized research computer codes, these combustion models are becoming more readily accessible as features in commercially available computational fluid dynamics (CFD) computer codes. Simulations made with such computer codes offer great potential for use in analyzing, designing, retrofitting, and optimizing the performance of fossil-fuel combustion and conversion systems.The purpose of this paper is to provide an overview of comprehensive combustion modeling technology as applied to fossil-fuel combustion processes. This overview is divided into three main parts. First, a brief review of the state-of-the-art of the various components or submodels that are required in a comprehensive combustion model is presented. These submodels embody mathematical and numerical representations of the fundamental principles that characterize the physico-chemical phenomena of interest. The submodel review is limited to those required for characterizing non-premixed, gaseous and pulverized coal gasification and combustion processes. A summary of the submodels that are available in representative computer codes is also presented.Second, the kinds of data required to evaluate and validate the predictions of comprehensive combustion codes are considered. To be viewed with confidence, code simulations must have been rigorously evaluated and validated by comparison with appropriate experimental data, preferably from a variety of combustor geometries at various geometric scales. Three sets of validation data are discussed in detail. Two sets are from the highly instrumented, pilot-scale combustor called the controlled profile reactor (CPR) (one natural gas-fired and one coal-fired), and the other set is for a full-scale, corner-fired 85 MW_e utility boiler.Third, representative applications of comprehensive combustion models are summarized, and three sets of model simulations are compared with experimental data. The model simulations for the three test cases were made using two commonly used, CFD-based computer codes with comprehensive combustion model features, PCGC-3 and FLUENT 4.4. In addition to the standard version of FLUENT, predictions were also made with a version of FLUENT incorporating advanced submodels for coal reactions and NO pollutant formation.     

Hydrogen and electricity: Parallels,interactions, and convergence

A future hydrogen economy would interact with and influence the electricity grid in numerous ways. This paper presents several concepts for understanding a hydrogen economy in the context of the co-evolution with the electricity sector and lays out some of the opportunities and challenges. _H2${\mathrm{H}}_2$ and electricity are complementary energy carriers that have distinct characteristics, which lead to more or less utility in different applications. Despite their differences, it is possible to understand a future hydrogen economy using some of the same techniques as electricity system analysis. Hydrogen pathways will lead to additional electric demands that will influence the structure, operation and emissions in the electric sector. Examples of convergence between these sectors include a number of options for _H2${\mathrm{H}}_2$ and electricity co-production and interconversion.     

Foxes,hedgehogs, and greenhouse governance: Knowledge,uncertainty, and international policy-making in a warming World

Global environmental challenges like greenhouse warming are characterized by profound uncertainties about the workings of complex systems, high stakes as to the costs and benefits of various possible actions, and important differences concerning the values that should shape public choices, confounding ready resolution by conventional decision-making procedures. So-called adaptive or reflexive governance strategies provide policy-makers an alternative framework for tackling the greenhouse problem. Adaptive governance employs deliberate experimentation and continuous learning-by-doing to test and adjust ongoing policy responses. Yet pursuing such approaches poses particular challenges to global climate cooperation. In an increasingly interdependent world, coordinating multiple parties experimentally adopting different climate measures could prove contentious. Unequivocal policy lessons may be difficult to draw and apply. Timely collective revisions to ongoing policies may prove more difficult still to define and agree. Advocates must engage these issues directly and develop means of addressing them if adaptive governance approaches are to allow policy-makers to formulate better strategies for combating climate change.     

Research,development and the prospect of combined cooling,heating, and power systems

The development of a combined cooling, heating, and power (CCHP) system in China is presented in this paper. The key scientific problems of a distributed energy system and the integration principles of a CCHP system are also pointed out. Moreover, two corresponding CCHP systems: one with the complementarities of fossil fuels energy and renewable energy, and the other integrated with desalination technology, are investigated. With special attention to thermal energy utilization, the integrating characteristics of these systems are likewise revealed, and the important role that the principle of cascade utilization of physical energy plays in system integration is identified. We have found that the energy-saving ratio of the integrated CCHP systems can be as high as 30%, and as such, the innovative CCHP systems suitable for China's sustainable development are also recommended.     

Hydrogen recovery,cleaning, compression,storage, dispensing,distribution system and End-Uses on the university campus from combined heat,hydrogen and power system

To address the problem of fossil fuel usage at the Missouri University of Science and Technology campus, using of alternative fuels and renewable energy sources can lower energy consumption and hydrogen use. Biogas, produced by anaerobic digestion of wastewater, organic waste, agricultural waste, industrial waste, and animal by-products is a potential source of renewable energy. In this work, we have discussed the design of combined heat, hydrogen and power (CHHP) system for the campus using local resources. An energy flow and resource availability study is hydrogen recovery, cleaning and energy End-Uses on the university campus from CHHP system. Following the resource assessment study, our team selects Fuel Cell Energy direct fuel cell (DFC) 1500TM unit as a molten carbonate fuel cell. The CHHP system provides the hydrogen for transportation, back-up power and other needs. The research presented in this paper was performed as part of the 2012 Hydrogen Student Design Contest. In conclusion, the CHHP system will be able to reduce fossil fuel usage, greenhouse gas (GHG) emissions and hydrogen generated is used to power different applications on the university campus.     

Grinding energy and physical properties of chopped and hammer-milled barley,wheat, oat,and canola straws

In the present study, specific energy for grinding and physical properties of wheat, canola, oat and barley straw grinds were investigated. The initial moisture content of the straw was about 0.13–0.15 (fraction total mass basis). Particle size reduction experiments were conducted in two stages: (1) a chopper without a screen, and (2) a hammer mill using three screen sizes (19.05, 25.4, and 31.75 mm). The lowest grinding energy (1.96 and 2.91 kWh t⁻¹) was recorded for canola straw using a chopper and hammer mill with 19.05-mm screen size, whereas the highest (3.15 and 8.05 kWh t⁻¹) was recorded for barley and oat straws. The physical properties (geometric mean particle diameter, bulk, tapped and particle density, and porosity) of the chopped and hammer-milled wheat, barley, canola, and oat straw grinds measured were in the range of 0.98–4.22 mm, 36–80 kg m⁻³, 49–119 kg m⁻³, 600–1220 kg m⁻³, and 0.9–0.96, respectively. The average mean particle diameter was highest for the chopped wheat straw (4.22-mm) and lowest for the canola grind (0.98-mm). The canola grinds produced using the hammer mill (19.05-mm screen size) had the highest bulk and tapped density of about 80 and 119 kg m⁻³; whereas, the wheat and oat grinds had the lowest of about 58 and 88–90 kg m⁻³. The results indicate that the bulk and tapped densities are inversely proportional to the particle size of the grinds. The flow properties of the grinds calculated are better for chopped straws compared to hammer milled using smaller screen size (19.05 mm).