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Here, CO gas environment has been used for reduction of graphene oxide (GO) and Pd precursor for preparation of varieties of Pd Nanostructures (PdNSs) with different shapes, size and surface morphologies on graphene support (RG-PdNSs). The extensive ab-initio Molecular Dynamics (MD) simulations and electronic structure calculations have been carried to get theoretical insight for the reduction process of GO by CO. The reduction of GO by CO as observed in experiment are confirmed by ab-initio MD snapshots at different time steps, energetic of the process and the Partial Density of States character of O2p orbital of GO before and after interaction with CO. The discrete states in the Partial Density of States of O2p orbital after CO attack indicates detachment of O from GO. The as-prepared RG-PdNSs are thoroughly characterized by different techniques. The simulation reveals the change in electronic properties from semi-metallic in pristine graphene to metallic due to the attachment of Pd in RG-PdNSs. The electrocatalytic activity of the as-synthesized nanostructures has been investigated toward the multi-functional energy conversion applications, the methanol oxidation reaction, formic acid oxidation reaction and oxygen reduction reaction. The RG-PdNSs exhibit excellent electrocatalytic performance compared to that of unsupported PdNSs and commercial Pd/C. Image 1 [ABSTRACT FROM AUTHOR]

Abstract Energy resource classification systems are useful assessment tools that support energy planning and project development, e.g., siting and feasibility studies. They typically establish standard classes of power, a measure of the opportunity for energy resource capture. In this study, we develop wave energy resource classification systems for the US based on wave power (J , kW/m) and its distribution with peak period ( T p , s). These metrics are calculated for 70,386 sites from partitioned bulk wave parameters generated from a validated 30-year WaveWatch III model hindcast. As the operating resonant period bandwidth of a wave energy converter (WEC) technology is an important design characteristic, the dominant period band containing the largest energy content is identified among three peak period band classes. These classification systems, comprised of four power classes and three peak period band classes, are based on the total wave power or the partitioned wave power in the dominant peak period band. They discriminate distinct trends in wave energy resource among five regions within the US, and provide useful information for energy planners, project developers, and technology designers. They also establish a framework for investigating the feasibility of a compatible wave climate (design load) conditions and WEC technology classification system to reduce design and manufacturing costs. Highlights • Classification parameters discriminate distinct trends in US wave climates. • Key attributes classified for energy planning and project development. • Key attributes classified for design and operation of WEC technologies. [ABSTRACT FROM AUTHOR]

Heating and cooling of buildings consume approximately 15% of all energy used in the United States. Such a large energy demand is primarily due to heating and cooling of the entire building space to temperature setpoints usually between 21.1 °C (70 °F) and 23.9 °C (75 °F). However, even with such a narrow range of temperature setpoints, more than 20% of the occupants do not feel thermally comfortable due to individual differences (e.g. age, gender, clothing, or physiology). The personal thermal management techniques, which create a local thermal envelope around a human body instead of heating or cooling the entire building space, have the potential to greatly reduce the building energy consumption and to enhance thermal comfort of individuals. In this study, a portable thermoelectric energy conversion unit (TECU) that converts electricity into cooling and heating energy is developed. The TECU supplies cool air (in the cooling mode) or warm air (in the heating mode) to regulate the thermal comfort of a human body. The cool or warm air is supplied through a tree-like rubber tube network that is knitted into a thermoregulatory undergarment. To achieve a cooling/heating target that provides satisfactory thermal comfort, the required cooling/heating power supply from the TECU is determined first while a theoretical model is then developed to guide the design of the TECU. To minimize the TECU weight and make it suitable for portable applications, relationships between weight and thermal resistances of commercial off-the-shelf heat sinks are established first, and a method to find the minimal weight of heat sinks for the TECU is then developed. This methodology is also applicable for other applications where heat sink weight needs to be minimized. The thermal manikin tests demonstrate that 24.6 W of personal cooling power and 18.5 W of personal heating power are achieved by using the TECU. [ABSTRACT FROM AUTHOR]

The cultivation of energy cane throughout the Southeastern United States may displace grazed pastures on organic soil (Histosols) to meet growing demands for biofuels. We combined results from a field experiment with a biogeochemical model to improve our understanding of how the conversion of pasture to energy cane during early crop establishment affected soil GHG (CO 2 , CH 4 , and N 2 O) exchange with the atmosphere. GHG fluxes were measured under both land uses during wet, hot and cool, dry times of year, and following a fertilization event. We also simulated the impact of changes in precipitation on GHG exchange. Higher fertilization of cane contributed to greater emission of N 2 O than pasture during warmer and wetter times of the year. The model predicted that energy cane emitted more nitrogen than pasture during simulated wetter than drier years. The modeled emission factor for N 2 O was 20 to 30-fold higher than the default value from IPCC (1%), suggesting that the default IPCC value could dramatically underestimate the consequences of this land conversion on the climate system. Predicted soil CH 4 and CO 2 fluxes were higher in pasture than energy cane, and this difference was not affected by increasing precipitation. Model simulations predicted that soils under first year cane emit more GHGs than pasture, particularly during wet years, but this difference disappeared two years after energy cane establishment. Our results suggest that management practices may be important in determining soil GHG emissions from energy cane on organic soils particularly during the first year of cane establishment. [ABSTRACT FROM AUTHOR]

Human health and economic prosperity are vulnerable to freshwater shortage in many parts of the world. Despite a growing literature that examines the freshwater vulnerability in various spatiotemporal contexts, existing knowledge has been conventionally constrained by a territorial perspective. On the basis of spatial analyses of monthly water and electricity flows across 2110 watersheds and three interconnected power systems, this study investigates the water-electricity nexus (WEN)'s transboundary effects on freshwater vulnerability in the continental United States in 2014. The effects are shown to be considerable and heterogeneous across time and space. For at least one month a year, 58 million people living in water-abundant watersheds were exposed to additional freshwater vulnerability by relying on electricity generated by freshwater-cooled thermal energy conversion cycles in highly stressed watersheds; for 72 million people living in highly stressed watersheds, their freshwater vulnerability was mitigated by using imported electricity generated in water-abundant watersheds or power plants running dry cooling or using nonfreshwater for cooling purposes. On the country scale, the mitigation effects were the most significant during September and October, while the additional freshwater vulnerability was more significant in February, March, and December. Due to the WEN's transboundary effects, overall, the freshwater vulnerability was slightly worsened within the Eastern Interconnection, substantially improved within the Western Interconnection, and least affected within the ERCOT Interconnection. [ABSTRACT FROM AUTHOR]

Ocean waves are a more predictable resource with a higher energy density compared to solar and wind. In addition, and specifically for the United States, resource locations with high wave power are close to major load centers being located along coastlines. These features have sparked a surge of attention in the United States on trying to economically harness ocean wave power. The aim of this article is to provide a concise review of the current state of ocean wave energy conversion technologies and industry status in the United States including research and development as well as commercial activities and governmental support, concluding with a discussion of future industry perspectives. Existing facilities, softwares as well as laboratory and open-water test facilities and resources, active research groups and commercial activities have been identified. Over one third of commercially active wave energy developers worldwide are located within the United States, but only a few have reached a high Technology Readiness Level. These findings, together with a relevant practical resource located within the U.S. and the advantageous nature of the resource compared to other renewable resources, indicate that the United States is well positioned to advance the wave energy industry in the near future. [ABSTRACT FROM AUTHOR]

Secure access to energy and food are two of the challenges facing the Northeast region of the United States. Traditional biofuel feedstocks, such as corn and oil seed, are able to satisfy energy requirements. However, they compete with food production for desirable land and water resources and, in any case, are not likely to exploit the region's current comparative advantages. This study investigates a potential solution to the energy security problem in the Northeast: biofuel from advanced feedstock in the form of net forest growth and woody wastes, of which the region has abundant endowments. The federal government has committed to requiring 79.5 billion liters (BL) of advanced biofuel production annually by 2022. We evaluate both the physical capacity for its production and its cost competitiveness using an input-output model of consumption, production, and trade in the 13-state region. The model minimizes resource use required to satisfy given consumer demand using alternative technological options and subject to resource constraints. We compile data from the technical literature quantifying state-level biofuel feedstock endowments and the technological requirements for cellulosic ethanol production. We find that exploiting the region's endowment of cellulosic feedstock requires either making the price of biofuels competitive with gasoline through subsidies or restricting imports of gasoline. Based on this initial investigation, we conclude that the region can produce significant amounts of advanced biofuel, up to 20.28 BL of cellulosic ethanol per year, which could displace nearly 12.5% of the gasoline that is now devoted to motorized transport in the region. [ABSTRACT FROM AUTHOR]

Sociotechnical imaginaries are collectively imagined forms of social life reflected in the design and fulfillment of technological projects. While it is implied that there may be contention around sociotechnical imaginaries, the literature on how that contention is manifested is scant. We use a frame-analytic approach to demonstrate the potency of collective action frames for making sense of the national imaginaries underpinning siting proposals. As a case study, we use woody biomass bioenergy development in northern Michigan. After briefly outlining the multiple frames that are encompassed in the imaginary of bioenergy development, we focus on the 'wood for energy' frame, employing the concept of 'frame keys' to demonstrate how national imaginaries are interpreted differently by local and nonlocal actors involved in community sitings of proposed facilities. We find not only that frame keys are essential to how the national imaginary of bioenergy is interpreted, (re)produced, and responded to but also that framing processes are related to social movements that coalesce around competing collective memories of place. [ABSTRACT FROM AUTHOR]

Abstract: The U.S. is the world's leading consumer of primary energy. A large fraction of this energy is used in boiler installations to generate steam and hot water for heating applications. It is estimated there are total 163,000 industrial and commercial boilers in use in the United States of all sizes. This paper characterizes the commercial and industrial boilers in the 37 states of the Midwest, Northeast, and Southern regions of the U.S. in term of number of units, unit capacity, aggregate capacity, and fuel type. A methodology is developed for evaluating and ranking the potential for converting from existing fossil-fuel boilers to biomass boilers in these states. In total, 3495 oil and coal boiler units in industrial and commercial buildings, and 1067 major wood energy facilities in the 37 eastern states were identified. These represent a subset of existing and potential conversions from fossil fuels to woody biomass. Based on this sample and energy consumption data from the Energy Information Administration (EIA), we estimate that there are currently 31,776 oil, coal, and propane boiler units over 0.5 MMBtus/hour capacity in these 37 states, representing a total energy consumption of 1.7 quadrillion Btus, or roughly the equivalent of 287 million barrels of oil. Were these units all converted to woody biomass fuel, they would consume a total of 121 million dry tons of wood per year, about three times the most recent US DOE estimates of woody biomass availability in those regions. Since only the most economical conversions typically occur, the reality of woody biomass market availability combined with thermal fossil-fuel consumption patterns suggests that roughly one-third of all potential projects could be achieved under sustainable utilization of existing biomass feedstocks in the three regions. Analysis of the results indicates that a targeted response to wood-conversion initiatives will yield the most successful program of fossil-fuel replacement in thermal applications. A ranking index developed in this study through analysis of existing boiler installations and availability of wood feedstocks suggests that the top ten states in the eastern United States on which to focus future messaging, feasibility studies, and policy development for potential woody biomass conversions are: 1. Maine, 2. Texas, 3. New York, 4. Florida, 5. Georgia, 6. Alabama, 7. South Carolina, 8. North Carolina, 9. Arkansas, 10. Pennsylvania. [Copyright &y& Elsevier]

Advanced biofuels produced from lignocellulosic biomass offer an exciting opportunity to produce renewable liquid transportation fuels, biochemicals, and electricity from locally available agriculture and forest residues. The growing interest in biofuels from lignocellulosic feedstock in the United States ( US) and the European Union ( EU) can provide a path forward toward replacing petroleum-based fuels with sustainable biofuels which have the potential to lower greenhouse gas ( GHG) emissions. The selection of biomass conversion technologies along with feedstock development plays a crucial role in the commercialization of next-generation biofuels. There has been synergy and, even with similar basic process routes, diversity in the conversion technologies chosen for commercialization in the EU and the US. The conversion technologies for lignocellulosic biomass to advanced biofuels can be broadly classified in three major categories: biochemical, thermochemical, and hybrid conversions. The objective of this review is to discuss the US and EU biofuel initiatives, feedstock availability, and the state-of-art conversion technologies that are potentially ready or are already being deployed for large-scale applications. The review covers and compares the developments in these areas in the EU and the USA and provides a comprehensive list of the most relevant ongoing development, demonstration, and commercialization activities in various companies, along with the different processing strategies adopted by these projects. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Abstract: For woody biomass to make a significant contribution to the United States' energy portfolio, harvesting contractors must economically harvest and transport energywood to conversion/processing facilities. We conducted a designed operational study in the Coastal Plain of North Carolina, USA with three replications of three treatments to measure harvesting productivity and costs when utilizing woody biomass. The treatments were: a conventional roundwood only harvest (control), an integrated harvest in which merchantable roundwood was delivered to mills and residuals were chipped for energy, and a chip harvest in which all stems were chipped for energy use. The harvesting contractor in this study typically delivers 2200–2700 t of green roundwood per week and is capable of wet-site harvesting. Results indicate that onboard truck green roundwood costs increased from 9.35 $ t−1 in the conventional treatment to 10.98 $ t−1 in the integrated treatment as a result of reduced felling and skidding productivity. Green energy chips were produced for 19.19 $ t−1 onboard truck in the integrated treatment and 17.93 $ t−1 in the chip treatment. Low skidding productivity contributed to high chip costs in the integrated treatment. Residual green biomass was reduced from 18 t ha−1 in the conventional treatment to 4 and 3 t ha−1 in the integrated and chip treatments, respectively. This study suggests that until energywood prices appreciate substantially, loggers are unlikely to sacrifice roundwood production to increase energywood production. This research provides unique information from a designed experiment documenting how producing energywood affects each function of a harvesting system. [Copyright &y& Elsevier]

Abstract: Fast pyrolysis of biomass is becoming increasingly important in some member countries of the International Energy Agency (IEA). Six countries have joined the IEA Task 34 of the Bioenergy Activity: Canada, Finland, Germany, Netherlands, UK, and USA. The National Task Leaders give an overview of the current activities in their countries both on research, pilot and demonstration level. [Copyright &y& Elsevier]

The National Aeronautics and Space Administration Glenn Research Center (GRC) has an extensive history in dynamic energy conversion dating back to the early 1960s. This legacy puts the GRC at the forefront of nuclear power systems using thermodynamic power cycles such as Stirling and Brayton. The advantages of dynamic energy conversion include high efficiency, long life, and scalability to high power. These attributes make Brayton and Stirling power cycles an ideal solution for nuclear energy conversion. [ABSTRACT FROM AUTHOR]

Background: Woody biomass is one of the most abundant biomass feedstocks, besides agriculture residuals in the United States. The sustainable harvest residuals and thinnings alone are estimated at about 75 million tons/year. These forest residuals and thinnings could produce the equivalent of 5 billion gallons of lignocellulosic ethanol annually. Softwood biomass is the most recalcitrant biomass in pretreatment before an enzymatic hydrolysis. To utilize the most recalcitrant lignocellulosic materials, an efficient, industrially scalable and cost effective pretreatment method is needed. Results: Obtaining a high yield of sugar from recalcitrant biomass generally requires a high severity of pretreatment with aggressive chemistry, followed by extensive conditioning, and large doses of enzymes. Catchlight Energy's Sugar process, CLE Sugar, uses a low intensity, high throughput variation of bisulfite pulping to pretreat recalcitrant biomass, such as softwood forest residuals. By leveraging well-proven bisulfite technology and the rapid progress of enzyme suppliers, CLE Sugar can achieve a high yield of total biomass carbohydrate conversion to monomeric lignocellulosic sugars. For example, 85.8% of biomass carbohydrates are saccharified for un-debarked Loblolly pine chips (softwood), and 94.0% for debarked maple chips (hardwood). Furan compound formation was 1.29% of biomass feedstock for Loblolly pine and 1.10% for maple. At 17% solids hydrolysis of pretreated softwood, an enzyme dose of 0.075 g Sigma enzyme mixture/g dry pretreated (unwashed) biomass was needed to achieve 8.1% total sugar titer in the hydrolysate and an overall prehydrolysate liquor plus enzymatic hydrolysis conversion yield of 76.6%. At a much lower enzyme dosage of 0.044 g CTec2 enzyme product/g dry (unwashed) pretreated softwood, hydrolysis at 17% solids achieved 9.2% total sugar titer in the hydrolysate with an overall sugar yield of 85.0% in the combined prehydrolysate liquor and enzymatic hydrolysate. CLE Sugar has been demonstrated to be effective on hardwood and herbaceous biomass, making it truly feedstock flexible. Conclusions: Different options exist for integrating lignocellulosic sugar into sugar-using operations. A sugar conversion plant may be adjacent to a CLE Sugar plant, and the CLE Sugar can be concentrated from the initial 10% sugar as needed. Concentrated sugars, however, can be shipped to remote sites such as ethanol plants or other sugar users. In such cases, options for shipping a dense form of sugars include (1) pretreated biomass with enzyme addition, (2) lignocellulosic sugar syrup, and (3) lignocellulosic sugar solid. These could provide the advantage of maximizing the use of existing assets. [ABSTRACT FROM AUTHOR]

The seventh U.S.-Japan Joint Seminar on Nanoscale Transport Phenomena was held in Shima, Japan, from December 11 to 14, 2011. The goals of this joint seminar were to provide a critical assessment of the state of the art and future directions in the field of nanoscale transport phenomena and energy conversion processes, to foster U.S.-Japan col-laborations, and to provide international exposure to a new generation of scientists in this field Issues discussed in the joint seminar were organized in 10 topical sessions, includ-ing (1) nanoscale thermophysical measurements; (2) optical characterization; (3) thermal and molecular transport; (4) phonon transport modeling; (5) energy storage and conversion; (6) nanoscale fluidics and phase change phenomena; (7) biological and organic systems; (8) interfacial thermal transport; (9) novel thermoelectric and thermal management mate-rials; and (10) nanocarbon materials and devices. In addition to these topical sessions, the joint seminar featured an opening plenary session and a closing plenary session as well as an expert panel, where leading experts provided critical assessment of the past progress and addressed future directions in the field. In addition, an evening poster session provided opportunities for graduate and postdoc students to present their latest research results. About 35 researchers from Japan and 31 researchers from the United States participated in the meeting. The meeting was organized by S. Maruyama, K. Fushinobu, L. Shi, and J. Lukes together with about 20 other participants who served as session chairs. Summaries of dif-ferent sessions of the seminar were prepared by the session and conference chairs and are collected into this report. [ABSTRACT FROM AUTHOR]

Abstract: The U.S. Energy Independence and Security Act of 2007 mandates the use, if produced, of 6.06 × 1010 L of advanced biofuels by 2022. The objective of this study is to determine the ethanol price necessary for a biorefinery to breakeven when using switchgrass as the single feedstock to produce ethanol. A holistic model that encompasses acquisition of land use services, feedstock production, harvest, harvest machine investment, feedstock logistics (storage, transportation), biorefinery location and size, and biorefinery investment is constructed and used to determine breakeven ethanol price. The model was solved for each of three biomass to ethanol conversion rates (250, 334, and 417 L of ethanol Mg−1 of biomass) and each of three biorefinery investment cost estimates ($2, $4, and $6 × 108 for a biorefinery with annual capacity of 379 × 106 L). Breakeven ethanol prices ranged from $0.44 L−1 with a conversion rate of 417 L of ethanol Mg−1 and an investment cost of $2 × 108, to $0.72 L−1 with a conversion rate of 250 L Mg−1 and an investment cost of $6 × 108. Improving the efficiency of conversion from 250 to 334 L Mg−1 decreases the estimated breakeven cost by $0. 07 L−1. Improved conversion efficiency results in a reduction of the total quantity of feedstock required and in the cost to deliver feedstock. Most of the cost reduction follows from reductions in land required (rent), and biomass harvest, storage, and transportation costs. [Copyright &y& Elsevier]

The article looks at the U.S. Department of Energy Advanced Research Project Agency - Energy (ARPA-E) program that awards research grants for clean energy ventures, with particular focus on projects incorporating biological research. An overview of several ARPA-E projects is provided, including investigations into the role of the carbon cycle in energy conversion, the plants engineered to replace oil (PETRO) experiment that builds on the process of plant photosynthesis to produce biomass energy, and the electrofuels program that involves the conversion of carbon dioxide into liquid fuel using microorganisms.

The yo-yo is a scientific toy that has fascinated young and old for thousands of years. According to yo-yo experts, the yo-yo is the second oldest toy in the world, after the doll. Yo-yo activities can be an excellent tool to help students explore many important physics concepts related to energy and motion. The rich history of the yo-yo offers opportunities to connect science with different cultures. Filipino culture in particular is very important in the history of the yo-yo, as it was a Filipino who introduced the toy in the United States and who also made key contributions to the toy's later success. [ABSTRACT FROM AUTHOR]

Abstract: Two-thirds of input energy for electricity generation in the USA is lost as heat during conversion processes. Additionally, 12.5% of primary fuel and 20.3% of electricity are employed for space heating, water heating, and refrigeration where low-grade heat could suffice. The potential for harnessing waste heat from power generation and thermal processes to perform such tasks is assessed. By matching power plant outlet streams with applications at corresponding temperature ranges, sufficient waste heat is identified to satisfy all USA space and water heating needs. Sufficient high temperature exhaust from power plants is identified to satisfy 27% of residential air conditioning with thermally activated refrigeration, or all industrial refrigeration and process heating from 100 to 150 °C. Engine coolant and exhaust is sufficient to satisfy all air conditioning and 68% of electrical demands in vehicles. Overall, this study demonstrates the potential to reduce USA primary energy demand by 12% and CO2 emissions by 13% through waste heat recovery. A detailed analysis of thermal energy demand in pulp and paper manufacturing is conducted to demonstrate the methodology for improving the fidelity of this approach. These results can inform infrastructure and development to capture heat that would be lost today, substantially reducing USA energy intensity. [Copyright &y& Elsevier]

A photobioreactor with an optical system that spatially dilutes solar photosynthetic active radiation has been designed, built, and tested at the Utah State University Biofuels Center. This photobioreactor could be used to produce microalgal biomass for a number of purposes, such as feedstock for an energy conversion process, or high-value products, such as pharmaceuticals and flutraceuticals. In addition, the reactor could be used to perform services such as removing nitrates, phosphates, and other contaminants from waste water as well as scrubbing toxic gases and carbon dioxide from flue gas. Preliminary tests were performed that compared growth and productivity kinetics of this reactor with that of a control reactor without spatial light-dilution. Tests indicated higher specific growth rates and higher areal and volumetric yields compared with the control reactor. The maximum specific growth rate, volumetric yield, and areal yield were 0.21 day-1, 0.059 gm l-1 day-1, and 15 gm m-2 day-1, respectively. Over 10 days of sequential-batch operation, the prototype photobioreactor converted direct-normal solar energy to energy stored in biomass at an average efficiency of 1%. The areal productivity, as mass per aperture per time, was three times higher than that of the control reactor indicating the photobioreactor design investigated holds promise. [ABSTRACT FROM AUTHOR]

Abstract: Next generation hydrocarbon biofuels have the potential to fulfill not only the biofuels production mandate of the Energy Independence and Security Act (EISA) of 2007, but also would not have to be exempted from the EISA-mandated increase in the corporate average fuel economy. Producing “green gasoline”, “green diesel” and “green jet fuel” from non-food lignocellulosic feedstocks such as forest waste and agricultural residue, and energy crops such as short rotation trees and perennial grasses grown on marginal or abandoned cropland will substantially lower greenhouse gas emissions and will not affect food prices. In this paper the development of the new paradigm of green gasoline from lignocellulose will be reviewed, the potential pathways to these infrastructure-compatible fuels will be discussed, and critical process design needs will be outlined. [Copyright &y& Elsevier]

Projected life cycle greenhouse gas (GHG) emissions and net energy value (NEV) of high-ethanol blend fuel (E85) used to propel a passenger car in the United States are evaluated using attributional life cycle assessment. Input data represent national-average conditions projected to 2022 for ethanol produced from corn grain, corn stover, wheat straw, switchgrass, and forest residues. Three conversion technologies are assessed: advanced dry mill (corn grain), biochemical (switchgrass, corn stover, wheat straw), and thermochemical (forest residues). A reference case is compared against results from Monte Carlo uncertainty analysis. For this case, one kilometer traveled on E85 from the feedstock-to-ethanol pathways evaluated has 43%-57% lower GHG emissions than a car operated on conventional U.S. gasoline (base year 2005). Differences in NEV cluster by conversion technology rather than by feedstock. The reference case estimates of GHG and NEV skew to the tails of the estimated frequency distributions. Though not as optimistic as the reference case, the projected median GHG and NEV for all feedstock-to-E85 pathways evaluated offer significant improvement over conventional U.S. gasoline. Sensitivity analysis suggests that inputs to the feedstock production phase are the most influential parameters for GHG and NEV. Results from this study can be used to help focus research and development efforts. [ABSTRACT FROM AUTHOR]

AbstractCost-effective implementation of microalgae as a solar-to-chemical energy conversion platform requires extensive system optimization; computer modeling can bring this to bear. This work uses modified versions of the U.S. Environmental Protection Agency's (EPA's) Environmental Fluid Dynamics Code (EFDC) in conjunction with the U.S. Army Corp of Engineers' water-quality code (CE-QUAL) to simulate hydrodynamics coupled to growth kinetics of algae (Phaeodactylum tricornutum) in open-channel raceways. The model allows the flexibility to manipulate a host of variables associated with raceway-design, algal-growth, water-quality, hydrodynamic, and atmospheric conditions. The model provides realistic results wherein growth rates follow the diurnal fluctuation of solar irradiation and temperature. The greatest benefit that numerical simulation of the flow system offers is the ability to design the raceway before construction, saving considerable cost and time. Moreover, experiment operators can evaluate the impacts of various changes to system conditions (e.g., depth, temperature, flow speeds) without risking the algal biomass under study. [ABSTRACT FROM AUTHOR]

Historical information concerning the development of high-temperature gas-cooled reactors in the USA and Russia is presented. The reactor facilities MHTGR (USA), VG-400 (Russia), VGM (Russia), GT-MGR (Russia, USA), and at the Fort St. Vrain nuclear power plant (USA) are described. The US programs for developing innovative high-temperature nuclear reactor technologies are examined. It is shown that the Russian and US technological developments for the fuel, reactor system, energy conversion system, and fission-product transport are similar. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this research is to present a best-case paradigm for geologic CO2 storage: CO2 injection and sequestration in saline formations below oil reservoirs. This includes the saline-only section below the oil–water contact (OWC) in oil reservoirs, a storage target neglected in many current storage capacity assessments. This also includes saline aquifers (high porosity and permeability formations) immediately below oil-bearing formations. While this is a very specific injection target, we contend that most, if not all, oil-bearing basins in the US contain a great volume of such strata, and represent a rather large CO2 storage capacity option. We hypothesize that these are the best storage targets in those basins. The purpose of this research is to evaluate this hypothesis. We quantitatively compared CO2 behavior in oil reservoirs and brine formations by examining the thermophysical properties of CO2, CO2–brine, and CO2–oil in various pressure, temperature, and salinity conditions. In addition, we compared the distribution of gravity number (N), which characterizes a tendency towards buoyancy-driven CO2 migration, and mobility ratio (M), which characterizes the impeded CO2 migration, in oil reservoirs and brine formations. Our research suggests competing advantages and disadvantages of CO2 injection in oil reservoirs vs. brine formations: (1) CO2 solubility in oil is significantly greater than in brine (over 30 times); (2) the tendency of buoyancy-driven CO2 migration is smaller in oil reservoirs because density contrast between oil and CO2 is smaller than it between brine and oil (the approximate density contrast between CO2 and crude oil is ∼100kg/m3 and between CO2 and brine is ∼350kg/m3); (3) the increased density of oil and brine due to the CO2 dissolution is not significant (about 7–15kg/m3); (4) the viscosity reduction of oil due to CO2 dissolution is significant (from 5790 to 98mPas). We compared these competing properties and processes by performing numerical simulations. Results suggest that deep saline CO2 injection immediately below oil formations reduces buoyancy-driven CO2 migration and, at the same time, minimizes the amount of mobile CO2 compared to conventional deep saline CO2 injection (i.e., CO2 injection into brine formations not below oil-bearing strata). Finally, to investigate practical aspects and field applications of this injection paradigm, we characterized oil-bearing formations and their thickness (capacity) as a component of the Southwest Regional Partnership on Carbon Sequestration (SWP) field deployments. The field-testing program includes specific sites in Utah, New Mexico, Wyoming, and western Texas of the United States. [Copyright &y& Elsevier]

The objective of this U.S.-Japan joint seminar series is to provide a cross-disciplinary and international forum for discussing and identifying outstanding science and technology issues in the area of nanoscale thermophysics and energy conversion and to foster collaboration among researchers in these areas. The first of this seminar series, championed by the late Professors Chang-Lin Tien and Kunio Hijikata, was held in Kanazawa, Japan, in June of 1993. Subsequent meetings have been held every three years, alternating venues between the United States and Japan. The Sixth U.S.-Japan Joint Seminar on Nanoscale Transport Phenomena—Science and Engineering was held in Boston, Massachusetts, July 13-16, 2008, and was organized by Professors Gang Chen from MIT, Fushinobu Kazuyoshi from Tokyo Institute of Technology, Shigeo Maruyama from Tokyo University, and Pamela Norris from University of Virginia. Nearly 100 scientists participated in the seminar. (The agenda of the seminar is attached at the end at this report[14].) The seminar included keynote sessions and invited sessions, as well as a dedicated poster session of selected presentations from an open call for papers. All papers presented in the regular sessions, the invited sessions, were upon invitation by the organizers. Invited sessions used a mixed form of communication: each speaker gave a 5-minute summary of his work followed by a 30-minute poster session of just the papers summarized orally, and then these speakers came back to the podium, serving as panelists to answer questions regarding their papers and session themes. This format offered good opportunities for the presenters to discuss their work with the participants. Reports for each session were summarized by session chairs. Following is a brief summary of the sessions. [ABSTRACT FROM AUTHOR]

This article seeks to add to the discussion about hemp prohibition in the United States by comparing the environmental performance of industrial hemp relative to its substitutes in a few key industrial applications. The life cycle environmental performance of industrial hemp products is of particular interest because environmental inefficiencies often impose costs on society as a whole, and additionally, the government has initiated a large number of programs intended both to reduce pollution and to increase production of bio-based industrial feedstocks. The positive attributes of industrial hemp are considered here in the context of counter-vailing attributes. [ABSTRACT FROM AUTHOR]

Increasing the yield of alfalfa (Medicago sativa L.) is a desirable breeding goal. The objective of this experiment was to test the hypothesis that hybrids between nondormant-derived alfalfa germplasm selected for winter hardiness and semidormant germplasm will express heterosis for yield. Four semidormant cultivars and four nondormant-derived populations were handcrossed in a half-diallel mating design to form population hybrids. Both seeded and transplanted trials were grown in Iowa between 2003 and 2005. Total biomass yield was measured at four harvests each year. The nondormant-derived germplasm produced lower yields than the semidormant cultivars. The hybrids between groups were intermediate to the parents with little evidence of heterosis in any environment or for any harvest during the year. Although particular crosses produced high yields in certain environments, no general heterotic pattern was observed between the two proposed groups. A Gardner and Eberhart Analysis III indicated the presence of variation for both general combining ability and specific combining ability effects of approximately equal magnitude among these eight populations. The nondormant germplasm sources used here do not form a new heterotic group for midwestern U.S. alfalfa breeding programs. [ABSTRACT FROM AUTHOR]

Microsatellite marker locus Xgwm 261 has been associated with reduced plant height attributed to the linked gibberellic acid (GA) sensitive Rht8c allele in wheat (Triticum aestivum L.). Our objective was to determine effects of allelic variation at the Xgwm 261 and Rht-B1 loci in two winter wheat recombinant inbred line (RIL) populations. 'Longhorn'/'Akron' and Longhorn/'Yuma' RIL populations were evaluated in controlled environments for GA sensitivity and coleoptile length and were grown in Colorado at five locations for 2 yr for agronomic evaluation. Microsatellite markers were used to identify alleles at the Xgwm 261 and Rht-B1 loci. In both populations, the Rht-B1b class showed reduced plant height (8.9% average), GA sensitivity (average 73.5%), coleoptile length (average 11.3%), and test weight (average 1.9%) relative to the Rht-B1a class. In the Longhorn/Yuma population, Rht-B1b and Xgwm 261 165-bp classes were shorter than the Xgwm 261 210-bp and Rht-B1a classes. Increased GA sensitivity and coleoptile length of the Xgwm 261 165-bp class were observed, although only in the Rht-B1a background. Plant height of the Xgwm 261 165-bp + Rht-B1a combination was intermediate to the shorter Xgwm 261 165-bp + Rht-B1b and the taller Xgwm 261-210-bp + Rht-B1a combinations. No negative associations attributed to the Xgwm 261 165-bp allele were observed. Our results suggest that the Xgwm 261 165-bp allele may provide reduced plant height, increased coleoptile length, and increased test weight when combined in a background with the Rht-B1a allele. [ABSTRACT FROM AUTHOR]

Abstract: Loblolly pine plantations are the most important source of forest products in the US and the slash remaining after conventional harvest represents a significant potential source of bioenergy. However, slash removal in intensive harvests might, under some circumstances, reduce site productivity by reducing soil organic matter and associated nutrients. Two complimentary studies in the Gulf Coastal Plain of the southeastern US were designed to test whether harvest intensity (level of biomass removal) could have a negative long-term impact on site productivity. Harvesting tree crowns in addition to the merchantable bole had a negative impact (18%) on pine biomass accumulation by age 7–10 years on 15 of 19 research blocks. Sites at risk of harvest-induced reductions in productivity were relatively unproductive prior to harvest and had low soil phosphorus (P) concentrations. Intensive harvesting, fertilization, and chemical control of non-crop vegetation were all energy efficient; the additional biomass energy gained through these practices was two-orders of magnitude greater than the energy needed to conduct the activities. Harvest of slash for bioenergy in the Gulf Coastal Plain of the southeastern US has the potential to reduce productivity on infertile soils, but fertilization has the potential to restore and even improve productivity on those sites in an energy-efficient way. [Copyright &y& Elsevier]

This article presents an assessment of energy inputs of the European Union (the 15 countries before the 2004 enlargement, abbreviated EU-15) for the period 1970-2001 and the United States for 1980-2000. The data are based on an energy flow analysis (EFA) that evaluates socioeconomic energy flows in a way that is conceptually consistent with current materials flow analysis (MFA) methods. EFA allows assessment of the total amount of energy required by a national economy; it yields measures of the size of economic systems in biophysical units. In contrast to conventional energy balances, which only include technically used energy, EFA also accounts for socioeconomic inputs of biomass; that is, it also considers food, feed, wood and other materials of biological origin. The energy flow accounts presented in this article do not include embodied energy. Energy flow analyses are relevant for comparisons across modes of subsistence (e.g., agrarian and industrial society) and also to detect interrelations between energy utilization and land use. In the EU-15, domestic energy consumption (DEC = apparent consumption = domestic extraction plus import minus export) grew from 60 exajoules per year (1 EJ = 1018 J) in 1970 to 79 EJ/yr in 2001, thus exceeding its territory's net primary production (NPP, a measure of the energy throughput of ecosystems). In the United States, DEC increased from 102 EJ/yr in 1980 to 125 EJ/yr in 2000 and was thus slightly smaller than its NPP. Taken together, the EU-15 and the United States accounted for about 38% of global technical energy use, 31% of humanity's energetic metabolism, but only 10% of global terrestrial NPP and 11% of world population in the early 1990s. Per capita DEC of the United States is more than twice that of the EU-15. Calculated according to EFA methods, energy input in the EU and the United States was between one-fifth and one-third above the corresponding value reported in conventional energy balances. The article discusses implications of these results for sustainability, as well as future research needs. [ABSTRACT FROM AUTHOR]

Negative environmental consequences of fossil fuels and concerns about petroleum supplies have spurred the search for renewable transportation biofuels. To be a viable alternative, a biofuel should provide a net energy gain, have environmental benefits, be economically competitive, and be producible in large quantities without reducing food supplies. We use these criteria to evaluate, through life-cycle accounting, ethanol from corn grain and biodiesel from soybeans. Ethanol yields 25% more energy than the energy invested in its production, whereas biodiesel yields 93% more. Compared with ethanol, biodiesel releases just 1.0%, 8.3%, and 13% of the agricultural nitrogen, phosphorus, and pesticide pollutants, respectively, per net energy gain. Relative to the fossil fuels they displace, greenhouse gas emissions are reduced 12% by the production and combustion of ethanol and 41% by biodiesel. Biodiesel also releases less air pollutants per net energy gain than ethanol. These advantages of biodiesel over ethanol come from lower agricultural inputs and more efficient conversion of feed-stocks to fuel. Neither biofuel can replace much petroleum without impacting food supplies. Even dedicating all U.S. corn and soybean production to biofuels would meet only 12% of gasoline demand and 6% of diesel demand. Until recent increases in petroleum prices, high production costs made biofuels unprofitable without subsidies. Biodiesel provides sufficient environmental advantages to merit subsidy. Transportation biofuels such as synfuel hydro-carbons or cellulosic ethanol, if produced from low-input biomass grown on agriculturally marginal land or from waste biomass, could provide much greater supplies and environmental benefits than food-based biofuels. [ABSTRACT FROM AUTHOR]

Focuses on the primary factors that limit the potential size of a biomass-energy industry in the U.S. Effect of inadequate rainfall on biomass yield; Major crop-based processes for producing bioenergy products; Reasons behind the non-adoption of crop fermentation as a process for producing ethanol.

• Wave energy for United States coastal waters is assessed using WaveWatchIII hindcast. • New wave energy resource attribute parameters are proposed. • Frequency, directional, and temporal variability of the wave energy are characterized. • The resource attributes corroborate with distinct regional wave climate features. The wave energy resource is characterized and assessed for coastal waters of the United States to evaluate regional opportunities and constraints for wave energy converter (WEC) projects. Partitioned wave parameters generated from a 30-year WaveWatch III model hindcast are used to estimate the total wave energy potential as an annual available energy (AAE), which is a theoretical annual energy production per unit energy capture length without considering energy conversion losses. The distribution of AAE by peak period, wave direction, month, and year is quantified using summary statistics, including peak period spread, AAE -weighted period, AAE -directionality coefficient, and inter-annual and seasonal temporal variability. Geographical distributions of the AAE and these five resource attributes delineate distinct wave energy resource regions within United States coastal waters, where different opportunities and constraints may influence regional energy planning, WEC project development, and WEC conceptual design. [ABSTRACT FROM AUTHOR]

Hydrogen can play a key role in the ongoing ‘energy transition’ to sustainable energy, and the formation of the Hydrogen Council aims to raise its profile and position hydrogen among the key solutions worldwide [ see page 1 ]. [ABSTRACT FROM AUTHOR]

The article discusses the Renewable Fuels Standard (RFS) established under U.S. President George W. Bush's administration. The new standard is aimed to increase ethanol and other biofuels in gasoline as a step toward oil independence, clean air and lower greenhouse gas emissions. It will cut petroleum use and annual greenhouse gas emissions will drop by up to 13.1 million metric tons by 2012. The program implements a provision approved by the Congress in the Energy Policy Act and is part of a larger initiative to increase the use of biofuels.