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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]

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]

Agricultural crops with a C4 photosynthetic pathway rapidly expanded across North America as early as 800 A.D. Their distribution continues to expand globally as demands for food and biofuel production increase. These systems are highly productive, having a significant impact on carbon and water exchange between the land and atmosphere. Here, we investigate the relative impact of agricultural C4 vegetation on the 13CO2 photosynthetic discrimination and atmospheric isotopic forcing in the upper Midwest, United States. We address three questions: (1) What is the relative importance of C3 and C4 species to the CO2 budget? (2) How do these different photosynthetic pathways influence the photosynthetic discrimination within this heterogeneous landscape? (3) To what extent does land use change (i.e., a change in C4 crops) impact atmospheric isotopic forcing and the isotopic signature of the atmosphere? These questions are addressed using measurements obtained from the University of Minnesota tall tower (244 m) trace gas observatory (TGO) over the growing seasons of 2007 and 2008 and are supported with scaled-up values of discrimination and isotopic forcing based on ecosystem-scale eddy flux observations and high-resolution land use data. Our land use analyses indicate that local and regional C4 production was higher by 10% in 2007 due to increased demand for biofuel. The 2007 growing season was also characterized by moderate drought as a consequence of low antecedent soil water content. Isotopic flux ratio measurements from TGO provide evidence that the increase in C4 land use and drier soil conditions of 2007 had a significant impact on the growing season 13CO2 photosynthetic discrimination, which ranged from 11.5 to 14.8 in 2007 and 12.4‰ to 17.4‰ in 2008. Isotopic partitioning indicated that C4 species accounted for about 20 to 40% of the growing season gross photosynthetic CO2 exchange. The isoforcing analysis revealed that C3 discrimination dominated the atmospheric δ13a budget, especially during spring and fall. Estimates of 13CO2 photosynthetic discrimination for this region support recently published isotope modeling studies that explicitly accounted for increases in C4 cropland, which has significant implications for estimating the terrestrial carbon sink strength based on inverse modeling techniques. [ABSTRACT FROM AUTHOR]

The article evaluates the effectiveness and economic value of corn and cellulosic ethanol production for reducing net greenhouse gas (GHG) emissions when produced on lands. The researchers compared the different land-use histories, with strategies achieved by set-aside programs such as the Conservation Reserve Program (CRP) in the U.S. Based on the results, they concluded that Carbon (C) releases from the soil after planting corn for ethanol may completely offset C gains attributed to biofuel generation. Furthermore, they noted that soil C isolated by setting aside former agricultural land was greater than the C generated by planting corn for ethanol on the same land for 40 years.

The article discusses about possible options for the conversion of excess crude glycerol resulting from biodesel production, into different by-products. According to the article, due to the increase in the cost of crude oil commonly used as a transportation fuel, and with the growth of awareness about environmental concerns, biodiesel production has grown worldwide. Because of these, the production of the main co-product glycerol has also increased and turned into an overproduction that became a glut in the market. The article tries to come up with options for catalytic and biological conversion of glycerol into various products to create a demand for the oversupply and remove the glut in the glycerol market.

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]

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]

The article reports on a class of economically viable solar power cells. The power cells called organic photovoltaics use organic molecules to capture sunlight to convert to electricity, which is cheaper but only convert small amounts of light in a limited time. A team of scientists from National Institute of Standards and Technology (NIST) led by David Germack discovered that changing the nature of the electrode surface helps in understanding how the organic solar cells perform and age.