• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 108
  • 19
  • 12
  • 10
  • 7
  • 6
  • 5
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 208
  • 208
  • 208
  • 70
  • 63
  • 61
  • 58
  • 49
  • 33
  • 30
  • 28
  • 28
  • 27
  • 26
  • 26
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Defining Biomass as a Source of Renewable Energy: The Life-Cycle Carbon Emissions of Biomass Energy and a Survey and Analysis of Biomass Definitions in States' Renewable Portfolio Standards, Federal Law, and Proposed Legislation / Life-Cycle Carbon Emissions of Biomass Energy and a Survey and Analysis of Biomass Definitions in States' Renewable Portfolio Standards, Federal Law, and Proposed Legislation

Zeller-Powell, Christine Elizabeth 06 1900 (has links)
xii, 97 p. / Electricity generated from woody biomass material is generally considered renewable energy and has been considered carbon neutral. However, recent criticism from scientists argues that the greenhouse gas (GHG) emission profile of bioenergy is nuanced and the carbon neutral label is inappropriate. An initial carbon debt is created when a forest is harvested and combusted for bioenergy. Because forests re-grow over a period of years, life cycle analyses show that bioenergy generated from whole trees from forests may not reduce GHG emissions in the short term, as required to combat climate change. State renewable portfolio standards and federal laws and proposed legislation designed to incentivize renewable energy typically define eligible forms of biomass that qualify for these incentives. Most of these definitions are very broad and do not account for GHG emissions from bioenergy. Federal and state laws should incorporate life cycle analyses into definitions of eligible biomass so that these laws incentivize biomass electricity that reduces GHG emissions in the next several decades. / Committee in charge: Roberta Mann, Chairperson; Scott Bridgham, Member
132

Sustainability Assessment for Strategic Material Flows Between Planned Construction Projects in the Stockholm County

Miyaoka, Mark January 2015 (has links)
Urban development demands on construction aggregates are set to rise dramatically over the coming years within the Stockholm region and a significant environmental challenge will be associated with the large flows of construction aggregates and excavated materials in and out of future development projects respectively.   Material banks receive construction and demolition waste (CDW), process this waste and supply recycled aggregates to the construction industry helping to reduce the demand on natural construction minerals.  The transportation of these material flows between the material banks and development areas is predominantly by road in the Stockholm region.  With the transport sector responsible for almost one third of green-house-gas (GHG) emissions in Sweden, there is a motivation for investigating the environmental benefits of minimising transportation distances of construction aggregates.  Quantities of CDW in the form of excavated granular soil and rock from future development locations within a case-study area comprising three municipalities; Botkyrka, Huddinge and Haninge, in the south of Stockholm, have been estimated based on their municipal comprehensive plans up to the year 2030.  This has been done with the assistance of an earthworks estimation tool, the ESAR model, developed by Ecoloop AB.  Distances between existing and planned material banks and future development areas together with the estimated material quantities have been combined to approximate total vehicle-kilometres for the transportation of these materials under a business-as-usual scenario up until 2030.  A comparison has been made to an alternative scenario of strategically located material banks within the case-study area, whereby a methodology has been developed within this study to strategically locate material banks utilising GIS software ArcMap together with land availability map layers for siting material banks previously developed under a separate related study.  In comparison to the business-as-usual scenario, one strategically located material bank within the case-study area reduces total material haulage distances of excavated granular soils and rocks from development areas to the material banks by approximately 42% or 3.67 million vehicle-kilometres, equating to a reduction of 3478 tonnes of CO2e throughout the time horizon of this study.  Another output from the ESAR model is the estimated construction aggregate demand for sub-surface earthworks backfilling activities.  A material flow analysis for the strategically located material bank indicates that the material bank is able to satisfy the sub-surface backfilling construction aggregate demand in the form of recycled aggregates throughout its operation.  Considering the flow of recycled aggregates back to development areas for backfilling earthworks activities, a total combined reduction of 45% or 5.54 million vehicle-kilometres of material haulage distance is achievable, equating to a saving of 5248 tonnes of CO2e.  Reductions in GHG emissions from strategically located material banks are likely to also be significant beyond the boundaries of this study and warrant further research.
133

Transit-oriented Smart Growth Can Reduce Life-cycle Environmental Impacts and Household Costs in Los Angeles

January 2014 (has links)
abstract: The environmental and economic assessment of neighborhood-scale transit-oriented urban form changes should include initial construction impacts through long-term use to fully understand the benefits and costs of smart growth policies. The long-term impacts of moving people closer to transit require the coupling of behavioral forecasting with environmental assessment. Using new light rail and bus rapid transit in Los Angeles, California as a case study, a life-cycle environmental and economic assessment is developed to assess the potential range of impacts resulting from mixed-use infill development. An integrated transportation and land use life-cycle assessment framework is developed to estimate energy consumption, air emissions, and economic (public, developer, and user) costs. Residential and commercial buildings, automobile travel, and transit operation changes are included and a 60-year forecast is developed that compares transit-oriented growth against growth in areas without close access to high-capacity transit service. The results show that commercial developments create the greatest potential for impact reductions followed by residential commute shifts to transit, both of which may be effected by access to high-capacity transit, reduced parking requirements, and developer incentives. Greenhouse gas emission reductions up to 470 Gg CO<sub>2</sub>-equivalents per year can be achieved with potential costs savings for TOD users. The potential for respiratory impacts (PM<sub>10</sub>-equivalents) and smog formation can be reduced by 28-35%. The shift from business-as-usual growth to transit-oriented development can decrease user costs by $3,100 per household per year over the building lifetime, despite higher rental costs within the mixed-use development. / Dissertation/Thesis / Masters Thesis Civil Engineering 2014
134

Comparando as emissões de gases de efeito estufa nas etapas da cadeia produtiva do etanol brasileiro. / Comparing greenhouse gas emission along the steps of Brazilian ethanol supply chain.

Celso Júnior Roseghini Lopes 09 December 2011 (has links)
Este trabalho utilizou a metodologia Renewable Transport Fuel Obligation (RTFO), desenvolvida pela Renewable Fuels Agency (RFA, 2008), para quantificar o volume de gases de efeito estufa emitido nas etapas do ciclo de vida do etanol: manejo agrícola da cana-de-açúcar, transporte da matéria-prima da lavoura até a usina, beneficiamento industrial, cogeração de energia elétrica e logística até uma base primária de armazenamento. O arcabouço metodológico foi aplicado em cinco diferentes regiões do Estado de São Paulo, o maior produtor brasileiro: Araçatuba, Assis, Ribeirão Preto, Jaú e Piracicaba. Ademais, objetivou-se examinar o impacto relativo que os seguintes tópicos têm nas emissões de gases de efeito estufa no ciclo de vida do etanol: (1) localização da produção de cana-de-açúcar; (2) utilização de diferentes combustíveis na etapa do manejo agrícola da cana-de-açúcar; (3) extinção da prática de queimar o canavial na fase da pré-colheita; e (4) utilização de uma logística intermodal para distribuir o etanol até uma base primária de armazenamento. No cenário base, considerou-se a utilização de óleo diesel no manejo agrícola da cana-de-açúcar, a prática de queimar previamente o canavial na fase da pré-colheita e a logística rodoviária para transportar o etanol das regiões produtoras até uma base primária de armazenamento localizada no porto de Santos-SP. Já para a análise de sensibilidade dos parâmetros de emissões, os demais cenários contemplam as possíveis combinações entre o uso de biodiesel no manejo agrícola (B20 ou B100), extinção da queima do canavial na fase da pré-colheita e logística rodo-ferroviária. Constatou-se que, independentemente do cenário analisado, em média, a maior parcela das emissões de gases de efeito estufa no ciclo de vida do etanol foi proveniente do manejo agrícola da cana-de-açúcar. Devido às características intrínsecas ao solo e a gestão das operações, as emissões são diferentes entre as regiões (amplitude de 60 kg de CO2e/tonelada de etanol). Ademais, essa etapa representou 51% e 62%, quando foi considerado, respectivamente, a logística rodoviária e a intermodalidade rodo-ferroviária para transportar o produto até Santos-SP. A utilização da intermodalidade de transporte rodo-ferroviária para distribuição do etanol corroborou para a minimização de gases de efeito estufa. Considerando a média dos cenários analisados, essa redução chegou a 13% no ciclo de vida e a 74% apenas na etapa da logística. Por fim, observou-se que existe minimização no volume de gases lançados na atmosfera em decorrência da sinergia entre o consumo de biodiesel B100 no manejo agrícola da cana-de-açúcar, a extinção da prática da queima do canavial na fase da pré-colheita e a utilização de logística intermodal rodo-ferroviária para se transportar o produto até uma base de armazenamento em Santos-SP. Em média, o volume de gases de efeito estufa emitidos diminuíram em 43% no ciclo de vida do etanol. / This thesis adopts the Renewable Transport Fuel Obligation (RTFO) methodology, developed by the Renewable Fuels Agency (RFA, 2008), to quantify the volume of greenhouse gases that are emitted during the following stages of the ethanol life-cycle: 1) sugarcane farm management, 2) transportation of the raw material from the field to the mill, 3) industrial processing, 4) co-generation of electricity, and 5) logistics to the primary storage base. The methodology is applied over five different regions of the State of São Paulo, the largest ethanol producing State in Brazil: Araçatuba, Assis, Ribeirão Preto, Jaú e Piracicaba. Furthermore, this thesis aims to exam the following impacts related to the greenhouse gases emitted by the stages of ethanol life-cycle: (1) sugar production location; (2) usage of different fuels at the stage of sugarcane farm management; (3) extinction of the practice of burning the sugarcane field during the pre-harvest; and (4) utilization of intermodal logistics in order to transport the end-product to a primary storage base. In the base scenario, it is assumed 1) the utilization of diesel oil in the farm management of sugarcane, 2) the practice of previously burning the sugarcane field in the pre-harvest and 3) the road logistics to transport ethanol from the producing regions to a primary storage base located in the port of Santos-SP. To analyze the sensibility of emission parameters, other scenarios comprehend the possible combinations between the usage of biodiesel in farm management (B20ou B100), as well as the extinction of the practice of burning the sugarcane field in the pre-harvest and road-rail logistics. It was verified that, on average, regardless of the analyzed scenario, the largest portion of greenhouse gas emissions during the ethanol life cycle is concentrated at the sugarcane farm management stage. Due to the intrinsic characteristics of the soil and the required operations management, the emissions differ between regions (amplitude of 60 kg CO2e/ton of ethanol). Moreover, when both, road logistics and road-rail intermodality to transport the product to Santos-SP are considered, this stage represents 51% and 62%, respectively. The utilization of road-rail transportation intermodality to distribute ethanol contributes to the reduction of greenhouse gas emission. By considering the average of analyzed scenarios, this reduction achieves 13% during the life cycle and 74% only during the logistics stage. Finally, it was observed that there is a reduction on the volume of gases emitted into the atmosphere as a result of synergy among the use of biodiesel B100 in sugarcane farm management, the extinction of the practice of burning the sugarcane field in the pre-harvest and the utilization of intermodal logistic in order to transport the product to a primary storage base in Santos-SP. On average, the emitted volume of greenhouse gas decreases by 43% in the life cycle of ethanol.
135

Estimativa da redução das emissões gases de efeito estufa através da intermodalidade no setor sucroenergético: uma aplicação de programação linear / Estimating greenhouse gas emission reductions through a diversification in transportation systems in the sugarcane industry: applying a linear programming system

Maria Andrade Pinheiro 19 April 2012 (has links)
A questão em torno do aquecimento global vem preocupando a sociedade mundial,sendo que os governantes e ambientalistas têm intensificado estudos e aplicações de medidas para tentar minimizar os efeitos das emissões de gases de efeito estufa na atmosfera. O setor de transporte é o segundo maior consumidor de energia, pois é muito dependente de combustíveis fósseis, que emitem quantidade elevada de CO2. O setor sucroenergético é um importante gerador de divisas para o país, sendo que a receita em 2010 foi de R$ 50 bilhões e as exportações alcançaram US$ 13,8 bilhões. O açúcar é um importante produto da pauta agrícola, o país exporta aproximadamente 70% da sua produção. O etanol é um importante gerador de energia, e consegue minimizar as suas emissões durante seu ciclo produtivo em até 90%, quando comparado a gasolina, seu principal concorrente. Dada a importância do transporte nas emissões de gases de efeito estufa e a possibilidade da mudança de modalidade reduzir essas emissões, o objetivo desta tese é estimar os benefícios da redução das emissões de CO2, a partir da mudança da matriz de transporte,para o setor sucroenergético. Para tanto foi utilizada a metodologia de programação linear, utilizando a otimização para a minimização das emissões e do custo de transporte. O softwar eutilizado foi o GAMS e quatro diferentes cenários para ambos os produtos foi traçado. O primeiro e o segundo foi modelado para a safra 2010/2011 e foi considerada a atual malha de transporte, sendo que a diferença entre os dois foi que no primeiro realizou-se a imposição da quantidade máxima de carga utilizando a intermodalidade com base no que foi escoado no ano 2010 e no segundo liberou-se esse volume. O objetivo é captar qual seria a configuração ideal tanto em termos econômicos como ambiental, caso não houvesse problemas estruturais e de infraestrutura para a utilização mais intensa de mais de um modal de transporte. No terceiro e quarto cenário foi utilizada uma estimativa para a safra 2020/2021, sendo que a diferença entre as duas modelagens foi que no terceiro manteve-se a mesma infraestrutura atualmente observada e no último expandiu-se as rotas intermodais passíveis de serem utilizadas considerando todas as obras de transporte apresentadas pela iniciativa privada, governo federal e as inseridas no Plano de Aceleração do Crescimento I e II. Os resultados apontaram um trade-off entre custo e emissão quando se compara os resultados da minimização das emissões e da minimização dos custos no mesmo cenário. No entanto, quando se confronta os resultados obtidos entre os cenários propostos verifica-se que é possível reduzir tanto os custos quanto as emissões para ambos os produtos. Para a safra 2020/2021, a simples possibilidade de se utilizar mais intensamente modais de transporte diferentes do rodoviário possibilitaria atingir em apenas três anos a redução de 6,6 milhões de toneladas de CO2 e R$ 3,3 bilhões no escoamento do açúcar e etanol. A mitigação através da mudança de modal poderia inserir o setor no mercado de carbono e conquistar mercados preocupados em obter produtos sustentáveis. / Global warming is a major and growing concern around the world, with governments and environmentalists intensifying studies involving measures aimed at minimizing the effects of greenhouse gas emissions into the atmosphere. Among major sectors, transportation is the second largest energy user and it remains highly dependent on fossil fuels that emit high amounts of CO2. The sugarcane industry is an important source of export revenues for Brazil: while total revenues for 2010 reached US$ 25 billion, about US$ 13.8 billion of that was generated by exports. Sugar is a key agricultural product on the Brazilian export agenda, with about 70% of production shipped to other countries. Ethanol, also produced from sugarcane, is a major ingredient of the countrys energy mix, which can also minimize emissions through its lifecycle by up to 90% compared to gasoline, its main competitor at the pump. Given the importance of transportation in greenhouse gas emissions and the possibility of diversifying transportation systems to achieve emission reductions, the goal of this thesis is to estimate the benefits the sugar-energy industry of reducing CO2 emissions through a diversification of transportation methods utilized by the industry. A methodology that relies on linear programming was used, aimed at optimization in order to minimize emissions and transportation costs. GAMS, a widely used software in linear programming, was utilized to construct four different scenarios for both products. Scenarios one and two covered the 2010/2011 harvest and considered the current transportation network, the difference being that scenario one considered a fixed cargo ceiling and various transport modes while scenario two, the cargo ceiling was eliminated. The idea was to arrive at an ideal configuration in both economic and environmental terms, considering no structural or infrastructure obstacles to more intense utilization of different modes of transport. Scenarios three and four relied on a long-range estimate for the 2020/2021 sugarcane harvest, the main difference between the two models being that model three is based on the same infrastructure that currently exists while model four considers an expansion of possible routes involving various transport modes that could be used, considering all transportation-related projects launched by private contractors and the federal government, including those that are a part of the governments Accelerated Growth Plans I and II, also known as PAC. The results point to a tradeoff between costs and emissions, when the results of minimizing emissions and costs within the same scenario are compared. However, when results between the proposed scenarios are pitted against one another, it can be concluded that it is possible to cut costs as well as emissions for both sugar and ethanol. In the 2020/2021 harvest, the simple possibility of utilizing a variety of road transport modes that dont involve road transportation would allow for a 6.6 million ton reduction in CO2 emissions, with a R$3.3 billion savings in cost of shipping sugar and ethanol. Mitigation through change transportation mode changes could finally insert the industry in carbon markets, while conquering markets where a greater concern with sustainability already exists.
136

Sustentabilidade aplicada à indústria : o uso eficiente da energia como forma de conservação ambiental / Industrial susteinability: the efficient energy use as form of environmental consertion

Francisco Savastano Neto 23 February 2010 (has links)
Uma parcela significativa da energia gasta no Brasil está relacionada ao consumo industrial (40,6%). Este trabalho propõe a mostrar um dos muitos caminhos para se obter a redução no consumo de energia elétrica na indústria e, com isso, diminuir as emissões associadas à geração, transmissão e consumo deste recurso. A busca da indústria pela eficiência energética, aliada às práticas econômicas, sociais e ambientais adequadas, pode colocá-la no caminho da sustentabilidade. A emissão de CO2/kWh foi o indicador escolhido para monitorar o comportamento do consumo de energia no desenvolvimento dos dois estudos de caso. O principal objetivo destes casos foi a redução das emissões de gases do efeito estufa por meio do uso eficiente da energia elétrica. No primeiro caso um sistema de moagem de polpa de celulose usada na fabricação de fraldas foi substituído por outro mais eficiente, obtendo-se uma redução no consumo de energia de 60%, o que gera uma redução estimada das emissões de CO2 de 80 t/ano. No segundo caso, o sistema de vácuo da formação da fralda foi trocado por outro mais eficiente, conseguindo-se uma redução de 56% no consumo de energia, com a conseqüente redução estimada de emissão de CO2 de 74 t/ano. Nestes casos observou-se que a utilização eficiente de fontes de energia, além de gerar um menor nível nas emissões de gases do efeito estufa, também contribui para a redução dos custos industriais. / A significant fraction of the energy spent in Brazil is associated with industrial consumption (40.6%). The purpose of this work is to demonstrate one of many ways to reduce electric energy consumption by the industry and, as consequence, reduce emissions associated with generation, transmission, and consumption of this resource. The search of energetic efficiency, coupled with economical, social, and environmental practices can shift the industry in the direction of a sustainability path. The emission of CO2/kWh was chosen as a sustainability indicator to monitor the energy consumption pattern during the development of this research. The main objective was to assess the reduction of the greenhouse gas emission, associated with a higher electric energy efficiency consumption strategy adopted in two cases that were analyzed. At the first case, a cellulose pulp milling system, used at a diaper manufacturing process, was replaced by another system with higher efficiency. The reduction in energy consumption reached 60%, and reduced greenhouse gas emissions in an estimated 80 ton/year. At the second case, a fan of the diaper vacuum system was also replaced by a more efficient system. The energy consumption decreased 56%, resulting in a greenhouse gas emissions reduction of 74 ton/year. These results demonstrate the relationship between adopting more energy efficient system, and the reduction in greenhouse gas emissions, that moreover, contributes to industrial cost reduction.
137

Análise das emissões de gases de efeito estufa e consumo energético setorial do Estado de São Paulo por meio da matriz insumo-produto / Assessing sector greenhouse gas emissions and energetic consumption of Sao Paulo State by means of input-output matrix.

Camila Isaac França 23 April 2013 (has links)
A Política Estadual de São Paulo de Mudanças Climática (PEMC) foi lançada em 2009. Esta política voluntária, independente de qualquer acordo nacional ou internacional, foi estabelecida para reduzir a emissão dos gases de efeito estufa em 2020 em 20%, de acordo com os níveis de 2005. Uma vez que a melhoria da eficiência energética está entre as ações de mitigação de emissões de carbono especificadas pela PEMC, este trabalho visa avaliar as emissões diretas e indiretas e o consumo energético das cadeias produtivas na economia do Estado de São Paulo. Conseqüentemente, este estudo combina dados da Matriz Insumo Produto com o Primeiro Inventário de Gases de Efeito Estufa do Estado de São Paulo (2011) e o Balanço Energético (2010). Todos os dados estão baseados nos valores do ano de 2004. O trabalho avalia três simulações. A primeira simulação compara as emissões totais e energia por unidade de demanda final, já a segunda simulação aplica o mesmo método, porém apenas contabiliza as emissões de energia. A terceira simulação é baseada na massa total de emissões diretas e indiretas e foi determinada por meio dos multiplicadores. Além disso, o efeito total de cada setor está relacionado às emissões diretas e indiretas geradas por uma unidade de demanda final. Baseado nos resultados das três simulações foi possível observar que as emissões indiretas representam quase 30% sobre as emissões totais, e que apesar deste número não ser mais representativo, a responsabilidade do setor é maior se as emissões indiretas forem consideradas. Os resultados da Simulação 1, identificam os setores que se destacam devido a altos geradores de emissões e energia: Outros da indústria extrativa e Cimento, de outro modo, se apenas os geradores das emissões fossem considerados Cimento e Pecuária teriam se destacado com aproximadamente 3,5 GgCO2e emitidos direta e indiretamente por 1 milhão de reais de demanda final. Já, de acordo com a Simulação 2, os setores que se destacam são: Cimento e Frabricação de aço e derivadoscom respectivamente 1,4 GgCO2e e 0,5GgCO2e de emissões totais emitidas por 1 milhão de reais de demanda final. Por fim, na Simulação 3, o setor de Transportes se destaca com 23% das emissões diretas, enquanto é responsável por 9% das emissões indiretas, correspondentes às emissões incorporadas pela demanda por serviços e produtos. Por outro lado, o setor Alimentos e bebidas é o que mais se destaca devido a 17% das emissões indiretas apesar de apresentar apenas 2% do total das emissões diretas. / The Sao Paulo State Climate Change Policy (CCP) was established in 2009. This voluntary policy, independent of any domestic and international accord, was established to reduce greenhouse gas emissions in 2020 by 20%, according to 2005\'s emission levels. Once the energy efficiency improvements are among the carbon mitigation actions specified by CCP, this present work aims to evaluate direct and indirect carbon dioxide equivalent emissions and energy consumption of supply chains in the Sao Paulo State\'s economy. Consequently, this study combines data from the Sao Paulo input-output matrix with the First Greenhouse Gas Emissions Inventory of Sao Paulo State (2011) and the Sao Paulo States Energy Balance (2010). All data used are based on 2004 values. Based on the CCP goal to reduce 20% in total emissions, this work assesses three simulations. The first simulation compares total emissions and energy by each final demand unit, whereas the second simulation applies the same method, but accounts for energy related emissions only. The third simulation is based on total direct and indirect emission mass. In addition, the work presents a comparison between all sectors in terms of their direct and indirect emissions, which is conveyed by emission multipliers. In addition, the total effect of each sector which is related to the direct and indirect emissions generated to one final demand unit, was assessed. Based on the results of the 3 simulations it was possible to see that indirect emissions represent almost 30% of the total emissions, and although this number is not more representative, in some cases sector\'s responsibility is greater if indirect emissions are accounted for. Results from Simulation 1 identify the sectors that stand out because of high energy and emission total effects: Other extractive industry and Cement. In comparision, if only total emissions effect are considered Cement and Livestock sectors stand out with approximately 3.5 GgCO2e emitted direct and indirectly for each 1 mi BRL of final demand, for each sector. Then, according to Simulation 2, the sectors that stand out are: Cement and Steel manufacture and products with respectvely 1.4 GgCO2e and 0.5 GgCO2e of total emissions emitted by each 1 mi BRL consumed by sector. Lastly, on Simulation 3, Transport is the sector that stands out with 23% of direct emissions, and 9% of the sum of indirect emissions, due to embodied emissions on services and products demand. Regarding indirect emissions, Food and beverage stands out, encompassing 17% of the indirect emissions and only 2% of total direct emissions.
138

An Analysis of UNT Commuting Patterns

Waskey, Susan L. 05 1900 (has links)
Academic institutions have recently organized to address their campus' greenhouse gas emissions. Along those lines, the University of North Texas (UNT) pledged to minimize the campus' environmental impact, and conducted a transportation survey in May 2009. The analyses confirm that commuting to campus was the second highest source (29%) of UNT's greenhouse gas emissions, following purchased electricity (48%). Students, faculty and staff drive over 89 million miles per year, 84% of which comes from students. Forty&#8208;two percent of student driving trips originate in the primary and secondary core areas surrounding Denton, which are partially served by buses. However, because these core areas are in close proximity to the campus, they contribute only 8% of the total student driving distance. Beyond the Denton core, the inner periphery of Denton County contributes another 22% of driving mileage. Students living in the outer periphery (outside Denton County) contribute the remaining 70% of total driving distance, and carpooling is currently their only alternative.
139

COVER CROPPING FOR SUSTAINABLE CO-PRODUCTION OF BIOENERGY, FOOD, FEED (BFF) AND ENHANCEMENT OF ECOSYSTEM SERVICES (ES)

Brodrick L Deno (9867779) 18 December 2020 (has links)
Increasing food, feed, fiber, biofuel production on decreasing amounts of arable land while simultaneously enhancing ecosystem services is challenging. Strategic inclusion of winter rye (<i>Secale cereale</i>) for biomass, silage, grain and Kura clover (<i>Trifolium ambiguum</i>) living mulch into existing Midwestern cropping systems may offer alternative economic income for farmers without displacing or reducing yields of primary crops. Research was conducted at the Purdue Water Quality Field Station (WQFS) where net balances of water, carbon, nitrogen, and radiation can be measured, and greenhouse gas (GHG) emissions are monitored. The agronomic performance of a corn-soybean rotation and continuous corn (controls) were compared to novel systems that included the use of rye cover cropping and Kura clover co-cropping. Rye was harvested for biomass/silage at heading immediately followed by corn or soybean planting. Continuous corn receiving 69 kg N ha<sup>-1 </sup>was planted into an establishment of Kura clover sod. Controls included these same systems without the rye or clover. GHG samples were taken via the static chamber method and tile-drained water sub-samples were collected, analyzed for nitrate, and load losses calculated. Biomass composition was determined and used to calculate herbage theoretical ethanol (EtOH) yields. Cereal rye did not significantly decrease corn or soybean grain yield. Averaged across years, Kura clover significantly depressed corn grain yields by nearly 70%. Kura clover significantly reduced flow-weighted tile drainage nitrate (NO<sub>3</sub><sup>-</sup>) concentrations, however cereal rye did not. Reductions in flow-weighted tile drainage nitrate (NO<sub>3</sub><sup>-</sup>) concentrations were found to largely occur during Quarter two (April, May, June). Cover crops did not significantly reduce annual tile drained NO<sub>3</sub><sup>-</sup> load losses in most cases, however, they did significantly reduce annual N<sub>2</sub>O emissions. Cumulative annual CH<sub>4</sub> emissions were not significantly altered. Annual CO<sub>2</sub>emissions were higher after the introduction of Kura clover and not significantly altered following the introduction of cereal rye. Averaged across years, theoretical ethanol yields in the Kura clover system produced 2,752 L EtOH ha<sup>-1</sup>, whereas EtOH production in cereal rye systems ranged from 3,245 to 4,210 L EtOH ha<sup>-1</sup>. Theoretical ethanol yields of continuous corn and rotational controls ranged from 2,982 to 3505 L EtOH ha<sup>-1</sup> for these same systems without the cereal rye of Kura clover. These data suggest that a multipurpose approach to cover crop inclusion can provide both environmental and economic advantages worthy of consideration.
140

Hållbarhetsredovisning av Teracom enligt GRI - EN 17

Forssell, Jonas January 2010 (has links)
Examensarbetet behandlar redovisning av klimatpåverkan från indirekta utsläppskällor hos Teracom AB. Fokus ligger på transporter, som innefattar godstransporter, tjänsteresor och personalens pendling till och från jobbet. Metoden som utvecklats är till för att samla in och behandla data som sedan presenteras i ton koldioxidekvivalenter. Varje del av de ingående områdena har beräknats var för sig med hjälp av i mestadels schabloner. Dessa schabloner har baserats på statistik från Teracoms leverantörer för att de ska stämma överens med verksamhetsområdet och de geografiska förutsättningarna. Resultatet från 2009 års beräkningar av transporterna blev 847 ton koldioxidekvivalenter att jämföra med 2173 ton från bränsleförbrukning och energianvändning. För att snabbt minska klimatpåverkan från transporterna bör följande förbättringsförslag ligga i fokus: rensa bland godstransportleverantörer och deras kundnummer, se över tekniken för resfira möten, främja tjänsteresor med tåg och lokaltrafik samt införa en koncerngemensam miljöbonus. De andra förbättringsförslagen bör också införas så snart som möjligt för att få en ökad effekt. / This master thesis deals with greenhouse gas reporting from indirect emission sources at Teracom AB. The focus is on transports which includes transportation of goods, business travel and commuting. The method that has been developed describes a way to collect and calculate data from transports and the result is presented in tons of carbon dioxide equivalents. Each of the parts has been calculated individually and the calculations are mostly made by templates. These templates are based on information provided by Teracoms suppliers. This because it gives a good accuracy in regard to the current scope of practice and geographical location. The result from transports during 2009 was 847 tons of carbon dioxide equivalents in comparison with the emissions generated by fuel combustion and energy generation which was 2173 tons. To immediately reduce the greenhouse gas emissions from transports the following improvements should be in focus; gather goods transports at fewer freight companies, ease the use of travel free meetings, promote the use of trains and public transports for business travels, and instate a general environment bonus for the whole Teracom group. The other suggested improvements should also be instated as soon as possible to get an increased effect.

Page generated in 0.0734 seconds