• 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.
121

Sociotechnical system studies of the reduction of greenhouse gas emissions from energy and transport systems

Olsson, Linda January 2015 (has links)
It is agreed that greenhouse gas (GHG) emissions from energy and transport systems must be reduced. Technical means exist to reduce GHG emissions from these sources. However, these emission-reduction measures are not implemented to a high enough degree. In this thesis, it is assumed that this is because the reduction of GHG emissions from energy and transport systems is a wicked problem. Unlike a tame problem, which has an unambiguous definition and a finite number of well-defined solutions, a wicked problem is difficult to define, and its solutions are often intertwined with the problem. The “wickedness” of a wicked problem lies in the extreme difficulty of solving the problem, rather than in the problem itself. In this thesis, the wicked problem of reducing GHG emissions from energy and transport systems is studied by applying a sociotechnical systems approach to the introduction of renewable vehicle fuels, the production and use of biogas, the introduction of electric vehicles, and the sustainability of district heating. In addition, this thesis discusses how energy issues are approached in different contexts, and what implications different actions can have on GHG emissions. The analysis shows that a sociotechnical approach to energy systems analysis can offer insights with regard to how system boundaries are handled within GHG-emission assessments and energy and transport policy. By problematising the use of system boundaries in GHG-emission assessments, this thesis explains how attempts to reduce GHG emissions could add to the wicked problem of GHGemission reductions from energy and transport systems. GHG-emission assessments can give very different results depending on system boundaries. While these results can be used in attempts to solve this wicked problem, they can also contribute to complicating it. As solutions to wicked problems are mainly found in policy, the use of system boundaries in policy is studied. Results show that narrow system boundaries in energy and transport policy can hamper sustainable development of energy and transport systems. The use of wider system boundaries could facilitate approaches to solve the wicked problem of reducing GHG emissions from energy and transport systems by making the consequences and effects of policy actions more clearly visible. / Det är välkänt att energi- och transportsystemens utsläpp av växthusgaser måste minska. Tekniska förutsättningar för att minska utsläppen av växthusgaser från användning av energi och transporter existerar. Ändå genomförs inte åtgärder för att minska utsläpp av växthusgaser i tillräcklig utsträckning. I föreliggande avhandling antas detta bero på att minskandet av utsläpp av växthusgaser från energi- och transportsystem är ett ’wicked problem’. Ett sådant problem är svårdefinierat och motståndskraftigt mot lösningar, eftersom lösningarna ofta är sammanflätade med problemet. I avhandlingen studeras frågan om hur utsläpp av växthusgaser från energi- och transportsystem kan minska. Introduktion av förnybara drivmedel, produktion och användning av biogas, introduktion av elbilar, samt hållbarhet i fjärrvärmesystem är områden som studeras med hjälp av ett sociotekniskt angreppssätt. Detta innebär att teknik studeras som en integrerad del av samhället, där teknik både påverkar och påverkas av aktörer och sociala strukturer. Analysen visar att ett sociotekniskt angreppssätt kan ge insikter om hur systemgränser hanteras inom energisystemforskning samt inom energi- och transportpolicy. Värderingar av växthusgasutsläpp, som utförs inom energisystemforskning, kan ge vitt skilda resultat beroende på hur det studerade systemet avgränsats. Resultaten kan användas i försök att minska utsläpp av växthusgaser från energi- och transportsystem, men detta kan leda till att problemet försvåras ytterligare. I avhandlingen förklaras detta genom problematisering av systemavgränsningar i värderingar av växthusgasutsläpp. Eftersom lösningar på ’wicked problems’ oftast återfinns inom policy, studeras även systemavgränsningar i policy. Det visas att snäva systemgränser inom energi- och transportpolicy kan hindra hållbar utveckling av energi- och transportsystem. Vidgade systemgränser skulle kunna underlätta ansatser att minska utsläpp av växthusgaser från energi och transportsystem genom att synliggöra konsekvenser och effekter av policyåtgärder.
122

Looking Beyond Fossil Fuel Divestment: Combating Climate Change in Higher Education

Xu, Robin 01 January 2015 (has links)
The young fossil fuel divestment movement is altering the landscape of climate change activism on US campuses. Student-run divestment campaigns are now pushing for institutions of higher education to withdraw their investments from the top 200 public fossil fuel companies. Despite student fervor, however, divestment has remained a controversial tactic for combating climate change. The first half of this thesis examines the stated motives of a selection of institutions that have officially agreed or declined to divest, and investigates the hypothesis that pushing for divestment alone will not achieve broad success because it does not appeal to a wide enough range of motives that may persuade people to engage in environmentally beneficial behavior. A multi-pronged approach to climate change activism that advocates for many initiatives to fight climate change may see more success than a singularly divestment-centered approach because it is more flexible and inclusive. The second half of this thesis offers an index of suggested actions from which activists and institutions of higher education could craft a multi-pronged approach to fight climate change. These measures, including climate neutrality goals, environmental education initiatives, and various types of internal financial mechanisms, may go a long way in improving the chances for success in climate change activism on campuses.
123

New insights into rebound effects : theory and empirical evidence

Murray, Cameron Keith January 2009 (has links)
The main objective of the thesis is to seek insights into the theory, and provide empirical evidence of rebound effects. Rebound effects reduce the environmental benefits of environmental policies and household behaviour changes. In particular, win-win demand side measures, in the form of energy efficiency and household consumption pattern changes, are seen as ways for households and businesses to save money and the environment. However, these savings have environmental impacts when spent, which are known as rebound effects. This is an area that has been widely neglected by policy makers. This work extends the rebound effect literature in three important ways, (1) it incorporates the potential for variation of rebound effects with household income level, (2) it enables the isolation of direct and indirect effects for cases of energy efficient technology adoption, and examines the relationship between these two component effects, and (3) it expands the scope of rebound effect analysis to include government taxes and subsidies. MACROBUTTON HTMLDirect Using a case study approach it is found that the rebound effect from household consumption pattern changes targeted at electricity is between 5 and 10%. For consumption pattern changes with reduced vehicle fuel use, the rebound effect is in the order of 20 to 30%. Higher income households in general are found to have a lower total rebound effect; however the indirect effect becomes relatively more significant at higher household income levels. In the win-lose case of domestic photovoltaic electricity generation, it is demonstrated that negative rebound effects can occur, which can potentially amplify the environmental benefits of this action. The rebound effect from a carbon tax, which occurs due to the re-spending of raised revenues, was found to be in the range of 11-32%. Taxes and transfers between households of different income levels also have environmental implications. For example, a more progressive tax structure, with increased low income welfare payments is likely to increase greenhouse gas emissions. Subsidies aimed at encouraging environmentally friendly consumption habits are also subject to rebound effects, as they constitute a substitution of government expenditure for household expenditure. For policy makers, these findings point to the need to incorporate rebound effects in the environmental policy evaluation process.’
124

Agricultural greenhouse gas emissions : costs associated with farm level mitigation : a thesis presented in partial fulfilment of the requirements for the degree of Master of Applied Economics in Economics at Massey University, Palmerston North, New Zealand

Wolken, Antony Raymond January 2009 (has links)
Agricultural greenhouse gas emissions within New Zealand account for 48 percent of all national greenhouse gas emissions. With the introduction of the emissions trading scheme farmers will soon be liable for their emissions, introducing additional physical constraints and financial costs. Farmers that still operate within the sector will have two options to meet emissions targets; to purchase carbon credits from the open market, or mitigate farm level emissions at added costs to the farmer. This study examines the latter case of assessing farm level options for mitigating greenhouse gas emissions, and quantifying the physical and financial costs associated with mitigation strategies. Results show that, based on the assumptions in the study, there are available options for dairy farmers to profitably meet Kyoto protocol emissions targets. Sheep and beef farmers can increase profit, but cannot meet Kyoto protocol emissions targets, through examined scenarios.
125

Microeconomic reform of wholesale power markets: a dynamic partial equilibrium analysis of the impact of restructuring and deregulation in Queensland

Simshauser, Paul Edward Unknown Date (has links)
This dissertation assesses the evolving structure and performance of the electricity supply industry (ESI) in Queensland following the restructuring and deregulation process undertaken in 1997 and 1998 respectively. This microeconomic reform process essentially replaced a vertically integrated electricity monopoly with an oligopolistic electricity market. In theory at least, restructuring a monopoly generator, and deregulating the product and capacity markets, should lead to lower electricity production costs, more cost-reflective wholesale electricity prices, and a generation plant expansion path that reflects the least-cost, optimal mix of baseload, intermediate and peaking technologies. In economic terms, the deregulated electricity market should deliver improvements in productive, allocative and dynamic efficiency. However, a likely side effect is a deterioration of ESI environmental performance, since the minimization of production costs are of paramount importance in a competitive market. This research has utilized historic data, direct comparisons to southern market outcomes, economic theory and the development and adaptation of a suite of economic cost and generation system simulation models to test the stated hypotheses of expected improvements in productive, allocative and dynamic efficiency, and a deterioration in environmental performance. This research has not had the availability of extensive historical market data upon which to draw. When research first commenced, less than six months of historical market data were available. At the time of completion of this dissertation, only three full financial years of data existed. Consequently, this research necessarily relied upon complex simulation models of economic cost and electricity generation systems, coupled with economic theory, to forecast market outcomes. The short history of market data is examined and tentative conclusions are drawn from this, which are integrated with the outputs of the simulation models. Simulation experiments have been conducted to identify the theoretically optimal market outcome, that is, the least-cost generation plant mix that would best meet the Queensland load curve, subject to a reliability constraint. This forms the 'base case', and represents that which would reasonably be expected to emerge under a centrally planned monopoly regime with a welfare maximization objective, characterised by perfect information and zero political intervention. Such a scenario establishes efficient generation system costs, prices and plant capacity mix. The 'base case' or centrally planned scenario is contrasted with forecast 'market scenarios'. Performance of the generation system is explored under specified scenarios using the economic cost and generation system simulation models, publicly available information about committed and expected future investment in plant capacity, incumbent generator trends and behavioural assumptions consistent with oligopolistic market theories. The analysis indicates that productive efficiency, or cost efficiency, is enhanced as a result of restructuring the monopoly generator into competing entities since competitive pressures force the generators to reduce costs in order to survive. Allocative efficiency, or price efficiency, declined during the first three years of the market, with all generators earning positive economic rents. The presence of these economic rents, coupled with conventional oligopolistic strategies associated with the theory of barriers to entry, resulted in a rush to commission new baseload capacity. Not surprisingly, dynamic efficiency appears to be deteriorating, with the market-induced capacity augmentation proving to be far greater than that considered optimal. Modelling results indicate that the oversupply of baseload capacity is expected to place considerable downward pressure on electricity prices, and thus allocative efficiency is forecast to improve in the intermediate run, much to the benefit of electricity consumers. In the long run, the oversupply of baseload capacity and subsequent low market price can be expected to frustrate the timely entry of new peaking or intermediate plant capacity, which will ultimately be required by the Queensland ESI given the strong electricity demand growth. What does appear to be emerging is a five or seven year electricity generation business cycle. Modelling results from this research also point to alarming environmental implications, with the general levels of greenhouse gas emissions of the electricity system increasing. While system thermal efficiency is declining, the rush of new, low-cost coal-fired capacity represents an inferior outcome to the alternative (i.e. efficient combined cycle gas plant) because the volume of greenhouse emissions is markedly higher. The outlook for Queensland's greenhouse gas emissions from electricity generation, in the absence of coincident environmental policies, is that they will more than double between the 1990 emission baseline, and the commencement of the Kyoto commitment period in 2008. Some clear warnings emerge from this research. The structure and performance of an ESI prior to deregulation is important if microeconomic reforms are to be successful. Too little generation capacity or transmission capacity is unlikely to provide a robust foundation for wholesale market implementation. To ensure that adequate competition will prevail, it will be necessary to restructure monopoly generators. The existing ESI needs to be characterised by ‘inefficiency’ if gains from trade are to be capitalized. An efficient centrally planned ESI is unlikely to benefit greatly from deregulation, particularly given that implementing a product market is likely to be a costly process. And finally, competitive markets deliver lowest cost, which is usually inconsistent with the most environmentally responsible outcome. As a result, if the environment is considered a policy imperative, it will be critical that ESI deregulation be complemented by coincident environmental regulations.
126

Hållbart byggande : Hur nyproduktion i trä och betong i Sverige påverkar miljön samt beslutsfattares beslutsgrunder gällande materialanvändning

Johansson, Stina January 2018 (has links)
Environmental changes are great challenges that humanity must face. This has spurred a flurry of activities aimed to lower our impact on our environment. This essay focuses on the aspects that influence decision makers when choosing construction materials as well as a look into whether wood has a lower impact on the environment compared to concrete when building houses. The materials have been assembled through surveys, interviews and literary studies. The primary factor that was given most weight among entrepreneurs and architects were robustness and safety, and concrete was in that regard favoured over wood. It is also possible that already established economical structures support the use of concrete instead of wood. Environmental aspects are not reflected among entrepreneurs as very important factors when it comes to choosing materials and for change to occur there needs to be more information supporting that wood can be as robust as concrete in structures for it to be similarly prioritised. Concerning wood’s impact on the climate and the environment compared to concrete there is a significant difference in woods favour if only the construction and production phase of the house’s life cycle is examined. However, there are studies that show that depending on the material used and the time the house is expected to remain there are instances where wood has a higher environmental impact than concrete. Conclusively, wood is not always more environmentally friendly. The environmental impact of a material in construction depends heavily on the life span of the house.
127

Industry and policy implementation of material efficiency

Cooper-Searle, Simone January 2018 (has links)
The UK has committed to deep, long-term reductions in national greenhouse gas emissions as part of a global effort to address climate change. Material efficiency, reducing the material inputs per service output, has long been identified as a globally underexplored mitigation strategy. Previous studies show unrealised technical potential to improve the efficiency of steel use, a large contributor of industry emissions, in the UK. This thesis explores why these opportunities may be unrealised along the steel supply chain.
128

Zhodnocení vybrané BAT techniky ve vybraném provozu s chovem drůbeže a zhodnocení jejich ekonomických dopadů

KUBÁŇ, Svatopluk January 2016 (has links)
The diploma thesis examines the production of gas emmissions (especially ammonia) arising from chicken farming. It focuses on its decrease and it also compares the gas concentrations while using electrolytic-oxydizing water. The work observes the expensiveness of the electrolyte water and compares the Air Emission Limit with the EU directivity. The measuring itself took place in a farm in Čekanice near Tábor. Air emission limit of ammonia has turned out to be 0,013 [kg NH3.ks-1.rok-1], more precisely 0,017 [kg NH3.ks-1.rok-1] for a hall without electrolyte-oxydizing water.
129

Hodnocení vybraných obilovin v konvenčním a ekologickém zemědělství z pohledu obsahu bílkovin a dopadu na emise skleníkových plynů / Evaluation of selected cereals in conventional and organic farming - protein content and impact on greenhouse gases emissions

PAVLOVÁ, Ivana January 2018 (has links)
Agriculture is, after fossil fuels, the second largest producer of greenhouse gas emissions, which are responsible for global climate change, and it is necessary to look for ways to reduce this environmental load. Cereals are the most cultivated crops in the world, so it is appropriate to examine their share of this load. The aim of the thesis was to evaluate and compare the environmental aspects of the cultivation of selected cereals (wheat, rye and barley) in the conventional and ecological farming system. The resulting environmental load was first calculated on 1 kg of grain, and then the load was recalculated to a load of 1 kg of protein contained in grain of selected cereals. Protein content in grain is one of the grain quality indicators. A simplified LCA method has been used for the environmental load calculations. This method is used for environmental impact assessments and covers the whole life cycle of the product.
130

Perfil do mercado de carbono no Brasil: análise comparativa entre os mercados regulado e voluntário

Souza, André Luis Rocha de January 2012 (has links)
179 p. / Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2012-12-19T20:11:02Z No. of bitstreams: 1 11a.pdf: 2500615 bytes, checksum: b6e1b8b3c11f149e14b2db6b9a1b4957 (MD5) / Made available in DSpace on 2012-12-19T20:11:02Z (GMT). No. of bitstreams: 1 11a.pdf: 2500615 bytes, checksum: b6e1b8b3c11f149e14b2db6b9a1b4957 (MD5) Previous issue date: 2011 / Essa pesquisa teve por objetivo geral investigar as principais diferenças entre o mercado de carbono regulado e voluntário no Brasil, no período de 2004 a 2011. Para alcançar o objetivo proposto, realizou-se uma pesquisa exploratória, de caráter bibliográfica e documental. Além disso, realizou-se o mapeamento de projetos no mercado de carbono voluntário no Brasil por meio de busca em bancos de dados e sites institucionais dos Padrões Internacionais (PIs) e dos proponentes, enquanto que os projetos do mercado de carbono regulado foram extraídos do banco de dados já existente no site do Ministério da Ciência e Tecnologia (MCT). Os dados secundários foram coletados por meio de analise de conteúdo dos Documentos de Concepção dos Projetos (DCP) mapeados e extraídos dos sites e banco de dados visitados. Verificam-se diferenças e semelhanças entre os mercados de carbono regulado e voluntário no Brasil, estando o primeiro mercado com 499 projetos, enquanto o segundo possui 111 projetos até o momento. Constatou-se que o mercado de comercialização de créditos de carbono brasileiro, seja ele na categoria regulada, seja na voluntária pode constituir-se em um instrumento econômico de extrema importância na viabilização da redução das emissões de GEE, contribuindo, assim, para a mitigação das mudanças climáticas e para o alcance das metas nacionais de redução de emissão de GEE fixadas na Política Nacional de Mudanças Climáticas (PNMC). Constatou-se também que o uso desses projetos como instrumentos de políticas públicas poderá contribuir significativamente para o cumprimento das metas fixadas pela PNMC e requer a criação de fundos de financiamentos voltados para esses mercados, viabilizando o aumento do número de projetos e suas contribuições para mitigar as mudanças climáticas, bem como a consolidação desses mercados no Brasil. Além disso, faz-se necessário que o governo estimule a iniciativa privada a investir em tecnologias ambientalmente seguras, viabilizando o aumento de energias renováveis para o país, que contribuam para a transição para uma economia de baixo carbono, além da criação de incentivos fiscais que motivem as empresas a desenvolverem os projetos de redução de emissão de GEE. Enfim, recomenda-se como novas investigações futuras a realização de pesquisa com o objetivo de verificar de que forma os créditos de carbono são comercializado no Brasil, identificando as características dos contratos fechados no mercado financeiro nacional, como também a realização de estudos de caso em projetos representativos do mercado de carbono voluntário no Brasil, visando confrontar os dados secundários obtidos via análise de dados com os dados primários obtidos através de pesquisa de campo. / Salvador

Page generated in 0.0753 seconds