Wood Waste and Race: The Industrialization of Biomass Energy Technologies and Environmental Justice.

In the 1980s, engineers developed new ways to use one of humanity's oldest fuel sources-wood-to create electrical power. This article uses envirotechnical analysis to examine the development of a wood-burning power plant in Flint, Michigan, and argues that when public officials began working with major energy corporations to build industrial biomass facilities in the 1980s and 1990s, new energy technologies designed to run on renewable fuels became part of an entrenched fossil fuel-based power structure that maintained deep historical inequalities. Like other examples of environmental injustice, the burdens of industrial-scale biomass power systems tended to fall on poor, nonwhite communities. By exploring the creation of the Genesee Power Station as part of an envirotechnical regime in Flint, this research seeks to develop conceptual bridges between the history of technology, environmental history, and environmental justice, and demonstrates the use of history to inform contemporary debates about sustainability.

Nuclear power in the 21st century: Challenges and possibilities.

The current situation and possible future developments for nuclear power--including fission and fusion processes--is presented. The fission nuclear power continues to be an essential part of the low-carbon electricity generation in the world for decades to come. There are breakthrough possibilities in the development of new generation nuclear reactors where the life-time of the nuclear waste can be reduced to some hundreds of years instead of the present time-scales of hundred thousand of years. Research on the fourth generation reactors is needed for the realisation of this development. For the fast nuclear reactors, a substantial research and development effort is required in many fields--from material sciences to safety demonstration--to attain the envisaged goals. Fusion provides a long-term vision for an efficient energy production. The fusion option for a nuclear reactor for efficient production of electricity has been set out in a focussed European programme including the international project of ITER after which a fusion electricity DEMO reactor is envisaged.

Supercritical synthesis of biodiesel.

The synthesis of biodiesel fuel from lipids (vegetable oils and animal fats) has gained in importance as a possible source of renewable non-fossil energy in an attempt to reduce our dependence on petroleum-based fuels. The catalytic processes commonly used for the production of biodiesel fuel present a series of limitations and drawbacks, among them the high energy consumption required for complex purification operations and undesirable side reactions. Supercritical fluid (SCF) technologies offer an interesting alternative to conventional processes for preparing biodiesel. This review highlights the advances, advantages, drawbacks and new tendencies involved in the use of supercritical fluids (SCFs) for biodiesel synthesis.

Adequação nutricional da alimentação escolar em município rural - Espírito Santo, Brasil / Nutritional adequacy of school feeding in rural municipality - Espírito Santo, Brasil

This study has assessed the adequacy of energy and nutrients in school meals offered to elementary students in a rural county of the State of Espirito Santo, Brazil; the values recommended in the National School Feeding Program (PNAE) were used as reference. It is an observational cross-sectional study developed in public schools through the analysis of portions offered to students aged 6 to 10 years old. Eighteen randomly selected school units (50% of total) were visited. Meals prepared by school cooks were weighed and portioned by 5kg capacity (1g accuracy) digital scale, according to standardized protocol. Dietpro 5i software was used for energy and nutrients quantification. The average portion offered weighed 248g, and contained 388 calories, 62g carbohydrate, 13g protein, 9g total fat, 2g fiber, 202µg vitamin A, 9.8mg vitamin C, 116mg calcium, 2.3mg iron, 42mg magnesium and 1.1mg zinc. The values for energy, carbohydrate, protein, lipid, vitamin A, vitamin C, iron and magnesium exceeded the recommendations of the National School Feeding Program (PNAE); on the other hand, the amounts of fiber, calcium and zinc were lower than the recommended ones. It is necessary to reformulate some aspects of school meals in the county in order to conform to the nutritional recommendations, such as incorporating more fruit and vegetables in the daily menus, defining and standardizing the portion of the foods/meals offered and continuously monitoring the activities defined in the school meals plan.

Este estudio evaluó la adecuación energética y nutricional de la alimentación escolar ofrecida a los estudiantes de educación básica en una municipalidad rural de Espírito Santo, Brasil, teniendo como valores de referencia los recomendados por el Programa Nacional de Alimentación Escolar (PNAE). Se trata de un estudio transversal, de observación, desarrollado en las escuelas municipales a partir del análisis de porciones de las comidas ofrecidas a los estudiantes de 6 a 10 años. Se visitaron 18 escuelas (50% del total), sorteadas previamente. Las porciones brindadas por las cocineras fueron pesadas en balanza digital con capacidad de 5kg y precisión de 1g, siguiendo un protocolo estandarizado. La cuantificación de energía y nutrientes fue realizada con el programa Dietpro 5i. La porción media ofrecida fue de 248g, y presentó: 388kcal, 62g de carbohidratos, 13g de proteínas, 9g de grasa total, 2g de fibra, 202µg de vitamina A, 9,8mg de vitamina C, 116mg de calcio, 2,3mg de hierro, 42mg de magnesio y 1,1mg de zinc. Los valores observados de energía, carbohidratos, proteínas, lípidos, vitamina A, vitamina C, hierro y magnesio superaron las recomendaciones del PNAE. Por otro lado, la cantidad de fibra, calcio y zinc fue más baja que la recomendada. La reformulación de algunos aspectos de la alimentación escolar en la ciudad es fundamental para cumplir con todas las recomendaciones nutricionales, como la incorporación de más frutas y hortalizas en el menú del día, la definición y estandarización de las porciones de los alimentos/preparaciones que se ofrecen y el monitoreo continuo de las actividades definidas en la planificación de la alimentación escolar.

O estudo avaliou a adequação de energia e nutrientes da alimentação escolar oferecida aos alunos do ensino fundamental de um município rural do Estado do Espírito Santo- Brasil, considerando como referência os valores preconizados no Programa Nacional de Alimentação Escolar (PNAE). Trata-se de um estudo transversal, observacional, desenvolvido nas escolas municipais a partir da análise da porção de preparações oferecidas aos alunos de 6 a 10 anos. Foram visitadas 18 unidades escolares (50% do total), previamente sorteadas. As preparações foram porcionadas pelas merendeiras e pesadas em balança digital, com capacidade de 5kg, precisão de 1g, de acordo com protocolo padronizado. Foi utilizado o programa Dietpro 5i para quantificação de energia e nutrientes. A porção média ofertada era de 248g, com 388kcal, 62g de carboidrato, 13g de proteína, 9g de lipídio, 2g de fibras, 202µg de vitamina A, 9,8mg de vitamina C, 116mg de cálcio, 2,3mg de ferro, 42mg de magnésio e 1,1mg de zinco. Os valores de energia, carboidrato, proteína, lipídio, vitamina A, vitamina C, ferro e magnésio encontrados superaram as recomendações do PNAE. Por outro lado, a quantidade de fibra, cálcio e zinco estava abaixo da recomendada. É fundamental a reformulação de alguns aspectos da alimentação escolar do município para atendimento de todas as recomendações nutricionais, tais como: incorporação de maior número de frutas, verduras e legumes nos cardápios diários, definição e padronização da porção dos alimentos/ preparações ofertados e contínuo monitoramento das atividades definidas no planejamento da alimentação escolar.

Effect of worldwide oil price fluctuations on biomass fuel use and child respiratory health: evidence from Guatemala.

OBJECTIVES: We examined the effect of worldwide oil price fluctuations on household fuel use and child respiratory health in Guatemala. METHODS: We regressed measures of household fuel use and child respiratory health on the average worldwide oil price and a rich set of covariates. We leveraged variation in oil prices over the 6-month period of the survey to identify associations between fuel prices, fuel choice, and child respiratory outcomes. RESULTS: A $1 (3.4% point) increase in worldwide fuel prices was associated with a 2.8% point decrease in liquid propane gasoline use (P < .05), a 0.75% point increase in wood use (P < .05), and a 1.5% point increase in the likelihood of the child reporting a respiratory symptom (P < .1). The association between oil prices and the fuel choice indicators was largest for households in the middle of the income distribution. CONCLUSIONS: Fluctuations in worldwide fuel prices affected household fuel use and, consequently, child health. Policies to help households tide over fuel price shocks or reduce pollution from biomass sources would confer positive health benefits. Such policies would be most effective if they targeted both poor and middle-income households.

[Applications of GIS in biomass energy source research].

Biomass resources have the characteristics of widespread and dispersed distribution, which have close relations to the environment, climate, soil, and land use, etc. Geographic information system (GIS) has the functions of spatial analysis and the flexibility of integrating with other application models and algorithms, being of predominance to the biomass energy source research. This paper summarized the researches on the GIS applications in biomass energy source research, with the focus in the feasibility study of bioenergy development, assessment of biomass resources amount and distribution, layout of biomass exploitation and utilization, evaluation of gaseous emission from biomass burning, and biomass energy information system. Three perspectives of GIS applications in biomass energy source research were proposed, i. e., to enrich the data source, to improve the capacity on data processing and decision-support, and to generate the online proposal.

Fluidized bed gasification of waste-derived fuels.

Five alternative waste-derived fuels obtained from municipal solid waste and different post-consumer packaging were fed in a pilot-scale bubbling fluidized bed gasifier, having a maximum feeding capacity of 100 kg/h. The experimental runs utilized beds of natural olivine, quartz sand or dolomite, fluidized by air, and were carried out under various values of equivalence ratio. The process resulted technically feasible with all the materials tested. The olivine, a neo-silicate of Fe and Mg with an olive-green colour, has proven to be a good candidate to act as a bed catalyst for tar removal during gasification of polyolefin plastic wastes. Thanks to its catalytic activity it is possible to obtain very high fractions of hydrogen in the syngas (between 20% and 30%), even using air as the gasifying agent, i.e. in the most favourable economical conditions and with the simplest plant and reactor configuration. The catalytic activity of olivine was instead reduced or completely inhibited when waste-derived fuels from municipal solid wastes and aggregates of different post-consumer plastic packagings were fed. Anyhow, these materials have given acceptable performance, yielding a syngas of sufficient quality for energy applications after an adequate downstream cleaning.

Functional materials for sustainable energy technologies: four case studies.

The critical topic of energy and the environment has rarely had such a high profile, nor have the associated materials challenges been more exciting. The subject of functional materials for sustainable energy technologies is demanding and recognized as a top priority in providing many of the key underpinning technological solutions for a sustainable energy future. Energy generation, consumption, storage, and supply security will continue to be major drivers for this subject. There exists, in particular, an urgent need for new functional materials for next-generation energy conversion and storage systems. Many limitations on the performances and costs of these systems are mainly due to the materials' intrinsic performance. We highlight four areas of activity where functional materials are already a significant element of world-wide research efforts. These four areas are transparent conducting oxides, solar energy materials for converting solar radiation into electricity and chemical fuels, materials for thermoelectric energy conversion, and hydrogen storage materials. We outline recent advances in the development of these classes of energy materials, major factors limiting their intrinsic functional performance, and potential ways to overcome these limitations.

Comparative life-cycle air emissions of coal, domestic natural gas, LNG, and SNG for electricity generation.

The U.S. Department of Energy (DOE) estimates that in the coming decades the United States' natural gas (NG) demand for electricity generation will increase. Estimates also suggest that NG supply will increasingly come from imported liquefied natural gas (LNG). Additional supplies of NG could come domestically from the production of synthetic natural gas (SNG) via coal gasification-methanation. The objective of this study is to compare greenhouse gas (GHG), SOx, and NOx life-cycle emissions of electricity generated with NG/LNG/SNG and coal. This life-cycle comparison of air emissions from different fuels can help us better understand the advantages and disadvantages of using coal versus globally sourced NG for electricity generation. Our estimates suggest that with the current fleet of power plants, a mix of domestic NG, LNG, and SNG would have lower GHG emissions than coal. If advanced technologies with carbon capture and sequestration (CCS) are used, however, coal and a mix of domestic NG, LNG, and SNG would have very similar life-cycle GHG emissions. For SOx and NOx we find there are significant emissions in the upstream stages of the NG/ LNG life-cycles, which contribute to a larger range in SOx and NOx emissions for NG/LNG than for coal and SNG.

An overview of energy sources in clinical use for the ablation of atrial fibrillation.

Recent years have seen many developments in the field of alternative energy sources for arrhythmia surgery. The impetus behind these advances is to replace the traditional, "cut-and-sew" Cox maze III procedure with lesion sets that are simpler, shorter, and safer but just as effective. There is demand for technology to make continuous, linear, transmural ablations reliably with a versatile energy source via an epicardial approach. This would make minimally invasive endoscopic surgical ablation of atrial fibrillation (AF) without cardiopulmonary bypass and with a closed chest feasible. These advances would shorten cardio-pulmonary bypass and improve outcomes in patients having surgical ablation and concomitant cardiac surgery. This review summarizes the technology behind alternative energy sources used to treat AF. Alternative energy sources include hypothermic sources (cryoablation) and hyperthermic sources (radiofrequency, microwave, laser, ultrasound). For each source, the biophysical background, mode of tissue injury, factors affecting lesion size, and advantages and complications are discussed.