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  • 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.
21

Potencial de geração de créditos de carbono e perspectivas de modernização do setor sucroalcooleiro do Estado de São Paulo através do mecanismo de desenvolvimento limpo / Potential Carbon Credits Generation and Modernization Perspectives of the São Paulo State Sugarcane Sector trough the Clean Development Mechanism

Beatriz Acquaro Lora 18 December 2008 (has links)
A necessidade mundial de mitigação dos gases de efeito estufa (GEE) e a mobilização internacional para atingir os objetivos de redução estabelecidos pela Convenção-Quadro das Nações Unidas para Mudanças Climáticas (CQNUMC) deram abertura para que finalmente as energias renováveis pudessem ser utilizadas e aumentassem sua parcela na matriz energética mundial. No Brasil, a sólida indústria sucroalcooleira atualmente desenvolve projetos de redução de emissões de carbono no âmbito do Mecanismo de Desenvolvimento Limpo (MDL) do Protocolo de Quioto, por meio de 18 projetos baseados na geração de energia elétrica renovável excedente através da cogeração, com exportação para a rede elétrica nacional, deslocando energia marginal termelétrica de origem fóssil, em apenas 20 unidades produtoras paulistas. Neste trabalho foi projetado um cenário ideal de reduções de emissões, que considerou a adesão total de 151 usinas paulistas para a safra de 2006/2007, para cinco cenários patamares tecnológicos de cogeração, com queima de bagaco e também aproveitamento da palha. Foi utilizando os parâmetros tecnológicos elaborados pela Comissão Especial de Bioenergia do Governo do Estado de São Paulo e o fator de linha de base de 0,268 tCO2e/MWh adotado pelos projetos de MDL em operação no Estado de São Paulo. No cenário tecnológico mais conservador as emissões evitadas somariam 1.404.593 tCO2e/ano. Para o cenário ideal as emissões evitadas somam 12.199.443 tCO2e/ano. Para composição do cenário ideal também foram calculadas as emissões referentes à queima da palha da cana-de-açúcar. / The world-wide necessity of Greenhouse Gases (GHG) mitigation and the intergovernmental mobilization to reach the objectives established by the United Nations Framework on Climate Change (UNFCCC) has opened space for the renewable energy increase in the worlds energy matrix. In Brazil, the solid sugarcane industry currently develops business in the scope of the Clean Development Mechanism (CDM) under the Kyotos Protocol, by means of 18 biomass-based projects, with renewable energy generation through bagasse cogeneration at 20 São Paulo States sugarcane production units. The projects activitys consists of increasing the efficiency in the bagasse cogeneration facilities, qualifying the units to sell surplus electricity to the national grid, avoiding the dispatch of same amount of energy produced by fossil-fuelled thermal plants to that grid. The reduced emissions are measured in carbon equivalent and can be converted into negotiable credits. The objective of this dissertation was to build a state of art scenario, calculating the potential emissions reduction through CDM projects for the sugarcane sector of São Paulo State, in which we consider the adherence of all the production units of the State to the CDM projects. The technological parameters used to elaborate the scenario were provided by the São Paulo State Government Bioenergy Special Commission and the baseline factor used of 0,268 tCO2e/MWh was that adopted by the CDM projects in operation in the State. The sugarcane database for the calculations was the production ranking provided by UNICA for the 2006/2007 season. In the most conservative scenario 131 units could avoid the emission of 1.404.593 tCO2e/year. For state of art scenario, the units could avoid 12.199.443 tCO2e/year. Also have been calculated the sugarcane straw burning emission for the sugarcane harvested in 2006/2007 season.
22

Klimatneutrala företag - kan IT minska utsläppen?

Al, Roza January 2007 (has links)
<p>The attention on environmental issues has never been as huge as today. The climate is changing and more and more evidence suggest that the cause behind climate changes is an increase of carbondioxide into the atmosphere. The increase in turn is considerd to be an act of human activity. Therefore some companies have decided to become climate neutral and implement information technology in their business in order to reduce their emissions. This thesis has three aimes: to calculate a small company´s carbondioxide emissions, study whether or not information technology could help to reduce these emissions and furthermore find out why some companies decided to become climate neutral and describe the concept climate neutral. The results show that if information technology is used properly and effectively there are great potential to reduce the emissions, especially emissions from transportation sector. Now that the environment issues has become number one in the news and in the political agenda many companies try to cut their emissions, which is why some companies decided to take one step further and become climate neutral. Most of the companies see this action as a necessity in order to survive in a high competitive market. By doing so, they get more PR and more credit from both their investers and custumers. That is also why GreenIT´s carbondioxide emissions where calculated here. GreenIT have intentions in becoming climate neutral and in order to becoming one they have to reduce their remaining emissions by investing in projects in developing countries. As GreenIT is a small company they don´t have large emissions to reduce. This action will not cost them much but will probably give them an advantage in the market and credit from other investors and customers.</p>
23

Clean development Mechanism (CDM) Policy and Implementation in China

Zeng, Lei January 2006 (has links)
China is the second largest emitter of greenhouse gases (GHG) in the world. Since 68% of its primary energy is from coal, China’s average energy intensity is 7.5 times higher than the EU and 4.3 times higher than the US (EU, 2003). Therefore, introducing advanced clean technologies and management to China represents opportunities for Annex I countries to obtain low-cost CERs through CDM projects, and access to one of the largest energy conservation markets in the world. The Chinese government considers that the introduction of CDM projects can bring advanced energy technologies and foreign investment to China, thereby helping China’s sustainable development. As energy efficiency is generally low and carbon intensity is high in both China’s energy supply and demand sectors, numerous options exist for cost-effective energy conservation and GHG mitigation with CDM. This study has focused on the following areas:  Clean development Mechanism (CDM) Policy and Implementation in ChinaClean development Mechanism (CDM) Policy and Implementation in ChinaChina’s energy development strategy and climate change, how to make CDM work for sustainable development in China?  CDM projects in China: policies assessment and recommendations for improvement.  Energy efficiency CDM projects and renewable CDM projects in China: case studies Firstly, this thesis reviewed the current CDM developments in China, attentions were given to the renewable energy, energy efficiency and methane capture project opportunities in China. Secondly, this study introduced China’s current policy on CDM implementation, and reviewed its permission requirements, institutional arrangements and project procedures. Based on the observations, this study analyzed the current problems and pointed out the shortfalls of the existing Chinese CDM policies and institutional settings. Options to remove these barriers were given as recommendations. This thesis also looked at the problem of that CDM was designed to have double dividends, to reduce the compliance cost of the Annex I countries and to contribute to sustainable development in Non Annex I Parties, but in reality, CDM has caused concerns about whether it could really support sustainable development in host countries. This study analyzed the reasons underpin this problem. Thirdly, based on the analysis made on energy efficiency and renewable CDM project development in China, case study was given on China’s landfill gas to energy project. This study analyzed the perspective of GHG mitigation through landfill gas capture and utilization in China, its opportunities and challenges. Moreover, this study demonstrated how CDM can add value to landfill gas-to-energy projects in China.
24

Clean Development Mechanism - Key to the future? : A minor field study of organizations working in rural areas in Vietnam with renewable energy sources.

Ewerton, Maria, Åkerblom, Linus January 2010 (has links)
A scholarship from the Swedish International Development Cooperation Agency (SIDA) made it possible for the authors to collect primary data on location in Vietnam. Through a study of three organizations we aimed to create an understanding of the Clean Development Mechanism. Despite all the natural resources and the potential of renewable energy in Vietnam, a large percent of the electricity production comes from coal and other sources that contribute to carbon dioxide emissions. However, there are organizations working nationwide with implementing renewable energy projects and educating the Vietnamese. Since the birth of carbon market in connection with the Kyoto Protocol new possibilities have emerged as e.g the Clean Development Mechanism. For example high quality carbon offsetting companies are working on projects that reduce greenhouse gas emissions. The purpose of this thesis is to study and describe how three organizations are working with renewable energy in rural areas in Vietnam and their connection to Clean Development Mechanism. We have carried out an explorative study with an inductive approach. Our three semi-structured interviews were conducted as personal interviews at location in Vietnam. We also had two informative meetings, also in Vietnam. Beyond, we had e-mail correspondents with a number of professionals in their field. Due to the heavy bureaucracy the Governmental process rate is slow, which are making projects such as in the area of renewable energy difficult to initiate. Also the Governmental interest in renewable energy as a source of generating electricity is limited. However, new policies are on the agenda which might increase the support for organisations working towards a sustainable development.
25

CDM Robust & Low Noise ESD protection circuits

Lubana, Sumanjit Singh 05 January 2009 (has links)
In spite of significant progress during last couple of decades, ESD still affects production yields, manufacturing costs, product quality, product reliability and profitability. The objective of an ESD protection circuit is to create a harmless shunting path for the static electricity before it damages the sensitive electronic circuits. As the devices are scaling down, while ESD energy remains the same, VLSIs are becoming more vulnerable to ESD stress. This higher susceptibility to ESD damage is due to thinner gate oxides and shallower junctions. Furthermore, higher operating frequency of the scaled technologies enforces lower parasitic capacitance of the ESD protection circuits. Hence, increasing the robustness of the ESD protection circuits with minimum additional parasitic capacitance is the main challenge in state of the art CMOS processes. Furthermore with scaling, the integration of analog blocks such as ADC, PLL’s, DLL’s, oscillator etc. on digital chips has provided cheap system on chip (SOC) solutions. However, when analog and digital chip are combined into single mixed-signal chip, on-chip noise coupling from the digital to the analog circuitry through ESD protection circuits becomes a big concern. Thus, increasing supply noise isolation while ensuring the ESD protection robustness is also a big challenge. In this thesis, several ESD protection circuits and devices have been proposed to address the critical issues like increased leakage current, slower turn-on time of devices, increased susceptibility to power supply isolation etc. The proposed ESD protection circuits/devices have been classified into two categories: Pad based ESD protection in which the ESD protection circuits are placed in the I/O pads, and Rail based ESD in which ESD protection circuit is placed between power supplies. In our research, both these aspects have been investigated. The Silicon Controlled Rectifier (SCR) based devices have been used for Pad ESD protection as they have highest ESD protection level per unit area. Two novel devices Darlington based SCR (DSCR) and NMOS Darlington based SCR (NMOS-DSCR) having faster turn-on time, lower first breakdown voltage and low capacitance have been proposed. The transient clamps have been investigated and optimized for Rail based ESD protection. In this research, we have addressed the issue of leakage current in transient clamps. A methodology has been purposed to reduce the leakage current by more than 200,000 times without having major impact on the ESD performance. Also, the issue of noise coupling from digital supply to analog supply through the ESD protection circuits has been addressed. A new transient clamp has been proposed to increase the power supply noise isolation. Finally, a new methodology of placement of analog circuit with respect to transient clamp has been proposed to further increase the power supply noise isolation.
26

CDM Robust & Low Noise ESD protection circuits

Lubana, Sumanjit Singh 05 January 2009 (has links)
In spite of significant progress during last couple of decades, ESD still affects production yields, manufacturing costs, product quality, product reliability and profitability. The objective of an ESD protection circuit is to create a harmless shunting path for the static electricity before it damages the sensitive electronic circuits. As the devices are scaling down, while ESD energy remains the same, VLSIs are becoming more vulnerable to ESD stress. This higher susceptibility to ESD damage is due to thinner gate oxides and shallower junctions. Furthermore, higher operating frequency of the scaled technologies enforces lower parasitic capacitance of the ESD protection circuits. Hence, increasing the robustness of the ESD protection circuits with minimum additional parasitic capacitance is the main challenge in state of the art CMOS processes. Furthermore with scaling, the integration of analog blocks such as ADC, PLL’s, DLL’s, oscillator etc. on digital chips has provided cheap system on chip (SOC) solutions. However, when analog and digital chip are combined into single mixed-signal chip, on-chip noise coupling from the digital to the analog circuitry through ESD protection circuits becomes a big concern. Thus, increasing supply noise isolation while ensuring the ESD protection robustness is also a big challenge. In this thesis, several ESD protection circuits and devices have been proposed to address the critical issues like increased leakage current, slower turn-on time of devices, increased susceptibility to power supply isolation etc. The proposed ESD protection circuits/devices have been classified into two categories: Pad based ESD protection in which the ESD protection circuits are placed in the I/O pads, and Rail based ESD in which ESD protection circuit is placed between power supplies. In our research, both these aspects have been investigated. The Silicon Controlled Rectifier (SCR) based devices have been used for Pad ESD protection as they have highest ESD protection level per unit area. Two novel devices Darlington based SCR (DSCR) and NMOS Darlington based SCR (NMOS-DSCR) having faster turn-on time, lower first breakdown voltage and low capacitance have been proposed. The transient clamps have been investigated and optimized for Rail based ESD protection. In this research, we have addressed the issue of leakage current in transient clamps. A methodology has been purposed to reduce the leakage current by more than 200,000 times without having major impact on the ESD performance. Also, the issue of noise coupling from digital supply to analog supply through the ESD protection circuits has been addressed. A new transient clamp has been proposed to increase the power supply noise isolation. Finally, a new methodology of placement of analog circuit with respect to transient clamp has been proposed to further increase the power supply noise isolation.
27

Investigating the feasibility of using CDM for Solar Home Systems in Ugandan Healthcare : – Exploring the potential for the ICT4MPOWER project and beyond

Stålmarck, Emma January 2011 (has links)
The Kyoto related mechanism – clean development mechanism (CDM) – can be used to generate certified emission reductions (CERs) for climate mitigating projects indeveloping countries. These credits provide an opportunity for additional project financing. This thesis has investigated the feasibility of using the CDM for off-grid solar home systems in order to electrify health centers in Uganda. The investigated scope includes two scenarios; one related to a particular project, ICT4MPOWER, and another one related to a national scenario of health center electrification. Two dimensions of feasibility have been targeted; legal prerequisites – various regulations that govern CDM projects – and value creating potential. The latter dimension has primarily focused on whether sufficient CDM-specific profit can be generated, but also looked at broader perspectives of value creation. Calculated break-even scenarios show that the expected scope of the ICT4MPOWER project is far too small to benefit from CDM. A national scenario improves the chances of generating a sufficient profit but would most likely still be too small. A project with broader national coverage would likely need to be arranged as a CDM program of activites (PoA). Such an arrangement has organizational benefits but does further worsen the financial outlook. Apart from the unfortunate value creating prospects, there are also obstacles related to legal prerequisites. To establish a baseline – the business as usual scenario which reflect the emission reduction potential of a project – may be difficult and somewhat ad-hoc. To demonstrate additionality – that the project would not have been carried out anyway – is another potential obstacle which applies to the PoA scenario. All in all, there are clear doubts that CDM would be a feasible solution for the investigated scenarios.
28

Electrostatic Discharge Protection Devices for CMOS I/O Ports

Li, Qing January 2012 (has links)
In modern integrated circuits, electrostatic discharge (ESD) is a major problem that influences the reliability of operation, yield and cost of fabrication. ESD discharge events can generate static voltages beyond a few kilo volts. If these voltages are dissipated in the chip, high electric field and high current are generated and will destroy the gate oxide material or melt the metal interconnects. In order to protect the chip from these unexpected ESD events, special protection devices are designed and connect to each pin of the IC for this purpose. With the scaling of nano-metric processing technologies, the ESD design window has become more critical. That leaves little room for designers to maneuver. A good ESD protection device must have superior current sinking ability and also does not affect the normal operation of the IC. The two main categories of ESD devices are snapback and non-snapback ones. Non-snapback designs usually consist of forward biased diode strings with properties, such as low heat and power, high current carrying ability. Snapback devices use MOSFET and silicon controlled rectifier (SCR). They exploit avalanche breakdown to conduct current. In order to investigate the properties of various devices, they need to be modeled in device simulators. That process begins with realizing a technology specific NMOS and PMOS in the device simulators. The MOSFET process parameters are exported to build ESD structures. Then, by inserting ESD devices into different simulation test-benches, such as human-body model or charged-device model, their performance is evaluated through a series of figures of merit, which include peak current, voltage overshoot, capacitance, latch-up immunity and current dissipation time. A successful design can sink a large amount of current within an extremely short duration, while it should demonstrate a low voltage overshoot and capacitance. In this research work, an inter-weaving diode and SCR hybrid device demonstrated its effectiveness against tight ESD test standards is shown.
29

Different views of how CDM projects contribute to sustainable development : A study of stakeholder perspectives of two large-scale renewable energy projets in Southern India

Balkmar, Liv January 2008 (has links)
Climate change and sustainable development are interlinked in several ways. A global sustainable development with decreased emissions of green-house gases is seen as a prerequisite for mitigation of climate change. Simultaneously a changing climate will put constraints to development endeavours in developing countries. Yet, a sustainable pathway should include both mitigation and adaptation to climate change facilitating social development, economic growth and a stable environment in developing countries. The Clean Development Mechanism (CDM) of the Kyoto Protocol is combining reduced green-house gas emissions with sustainable development in the CDM project’s host country. This so called dual goal has turned out hard to fulfil, especially the local development objective.   This thesis studies how CDM projects contribute to local development and how this development is viewed differently by various stakeholders. This was made through qualitative interviews with actors connected to two CDM projects in Southern India. In addition, a literature review and a document study was made. The projects chosen are in the renewable energy sector, using biomass fuel. Renewable energy is regarded as an important factor to come to terms with increasing green-house gas emissions.   The results from the literature review and document study show that the expected contribution by CDM projects to local sustainable development is usually expressed in terms of employment, distribution of benefits, social infrastructure, access to energy and technology transfer. The environmental benefit is included in the reduction of green-house gas emissions. In the context of local development, stakeholder participation is brought up as an important factor. The results of the interviews present similar categories of development linked to CDM projects. However, differing views of actual local development assisted by the CDM project was discerned in the answers.   This study points to scale-related problems linked to the global benefit of mitigation of climate change in combination with local development. In conclusion, there is a need for monitoring and evaluation of actual contribution by CDM projects to local sustainable development. To facilitate local sustainable benefits of CDM projects, enhanced stakeholder participation is necessary during the whole project activity period.
30

Different views of how CDM projects contribute to sustainable development : A study of stakeholder perspectives of two large-scale renewable energy projets in Southern India

Balkmar, Liv Unknown Date (has links)
<p>Climate change and sustainable development are interlinked in several ways. A global sustainable development with decreased emissions of green-house gases is seen as a prerequisite for mitigation of climate change. Simultaneously a changing climate will put constraints to development endeavours in developing countries. Yet, a sustainable pathway should include both mitigation and adaptation to climate change facilitating social development, economic growth and a stable environment in developing countries. The Clean Development Mechanism (CDM) of the Kyoto Protocol is combining reduced green-house gas emissions with sustainable development in the CDM project’s host country. This so called dual goal has turned out hard to fulfil, especially the local development objective.</p><p> </p><p>This thesis studies how CDM projects contribute to local development and how this development is viewed differently by various stakeholders. This was made through qualitative interviews with actors connected to two CDM projects in Southern India. In addition, a literature review and a document study was made. The projects chosen are in the renewable energy sector, using biomass fuel. Renewable energy is regarded as an important factor to come to terms with increasing green-house gas emissions.</p><p> </p><p>The results from the literature review and document study show that the expected contribution by CDM projects to local sustainable development is usually expressed in terms of employment, distribution of benefits, social infrastructure, access to energy and technology transfer. The environmental benefit is included in the reduction of green-house gas emissions. In the context of local development, stakeholder participation is brought up as an important factor. The results of the interviews present similar categories of development linked to CDM projects. However, differing views of actual local development assisted by the CDM project was discerned in the answers.</p><p> </p><p>This study points to scale-related problems linked to the global benefit of mitigation of climate change in combination with local development. In conclusion, there is a need for monitoring and evaluation of actual contribution by CDM projects to local sustainable development. To facilitate local sustainable benefits of CDM projects, enhanced stakeholder participation is necessary during the whole project activity period.</p><p><strong> </strong></p>

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