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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.
1

Applications of Thermal Energy Storage with Electrified Heating and Cooling

Ryan, Erich 28 June 2022 (has links)
With a clear correlation between climate change and rising CO2 emissions, decarbonization has garnered serious interest in many sectors to limit the adverse effects of global warming. Heating and cooling systems have been a focus of decarbonization efforts, with heat pumps becoming more popular in the United States and abroad. In fact, heating, ventilation, and air conditioning accounts for nearly 27% of total energy use in the United States [1]. Ground source heat pumps (GSHP) utilizing borehole heat exchangers (BHE) have been shown to be an effective method of electrifying heating and cooling systems, maintaining some of the best performance for any electrified heating and cooling system currently available. Electrification, however, does come with some significant challenges. One of particular importance is the significant increase in peak demand during the heating season, which can result in a serious cost increase for the operator of the electric heating system, as well as adding operational complexities to grid operations by shifting from a summer peak to a winter peak as more heating loads are electrified. Thermal energy storage (TES) has been shown to be effective in mitigating the increase in peak demand that is seen with electrified heating and cooling systems. By storing thermal energy during off-peak hours, demand can be effectively shifted away from the peak hours. In this study, we investigate the potential of a ground source heat pump coupled with a TES system, in the form of water storage tanks, for the University of Massachusetts, as a way of decarbonizing the institution’s HVAC system while minimizing operating and installed costs.
2

Studies in Nuclear Energy: Low Risk and Low Carbon

Ford, Michael J. 01 May 2017 (has links)
The amount of greenhouse gas emissions mitigation required to prevent the most dramatic climate change scenarios postulated in the 2014 IPCC Synthesis Report is substantial. Prior analyses have examined the potential for nuclear energy to play a role in decarbonizing the energy sector, one of the largest contributors to emissions worldwide. However, advanced, non-light water reactors, while often touted as a viable alternative for development, have languished. Large light water development projects have a repeated history of extended construction timelines, re-work delays, and significant capital risk. With few exceptions, large-scale nuclear projects have demonstrated neither affordability nor economic competitiveness, and are not well suited to nations with smaller energy grids, or to replace fossil generation in the industrial process heat sector. If nuclear power is to play a role in decarbonization, new policy and technical solutions will be needed. In this manuscript, we examine key aspects of past performance across the nuclear enterprise and explore the future potential of nuclear energy worldwide, focusing on policy and technical solutions that may be needed to move nuclear power forward as a part of a low-carbon energy future. We do so first at a high level, examining the history of nuclear power research and development in the United States, the nation that historically has led the way in the development of this generating technology. A significant portion of our analysis is focused on new developments in this technology – advanced non-light water reactors and small modular reactors. We find that while there are promising technical solutions available, improved funding and focus in research and new models of deployment may be needed if nuclear is to play a continuing or future role. We also find that in examining potential new markets for the technology, a continuing focus on institutional readiness is critical.
3

Dekarbonizace a společná dopravní politika EU / Decarbonization and Common Transport Policy the EU

Volková, Anna January 2013 (has links)
The target of this diploma theses is to evaluate the Common Transport Policy of the EU and the development of decarbonization in world and European economies. The first chapter focuses on the role of transport in economy, common transport policy of the EU and its environmental aspects. Next chapter is specialized in adoption of the Kyoto protocol, than in the global and European development and decarbonization in transportation. Last third chapter aims on the future of decarbonization and the alternative fuels.
4

Ground Source Heat Pumps: Considerations for Large Facilities in Massachusetts

Wagner, Eric 02 April 2021 (has links)
There has been a significant increase in the interest and implementations of heat pump systems for HVAC purposes in general and of ground source heat pumps (GSHPs) in particular. Though these systems have existed for decades, primarily in Europe, there has been an upward trend particularly in the United States in recent years. With the world-wide push toward CO2 emissions reduction targets, interest in heat pump systems to reduce CO2 emissions from heating and cooling is likely to only increase in the future. However, more than ever, financial considerations are also key factors in the implementation of any system. Ground source heat pumps (GSHPs) coupled to vertical borehole heat exchangers (BHEs) have been promoted as a viable heat pump system in climates where traditional air source heat pumps (ASHPs) may operate inefficiently. This type of system claims superior performance to ASHPs due to the relatively consistent temperature of the ground compared to the air, offering a higher temperature heat source in the heating season and a lower temperature sink in the cooling season. Projects designing and installing such a GSHP system have been implemented at large scales on several university campuses to provide heating and cooling. In this study, we aim to test the idea that a GSHP system, as a replacement for an existing CHP heating and conventional cooling systems, could reduce CO2 emissions, as well as provide a cost benefit to a large energy consumer, in this case the University of Massachusetts. This will be done using the existing heating and cooling loads provided by the conventional system and an established technique of modeling the heat pumps and BHEs. The GSHP system is modeled to follow the parameters of industry standards and sized to provide the best overall lifetime cost. The result on the overall annual costs, emissions, and university microgrid are considered.
5

Pipeline demagogy? : The EU’s framing of Russia in the policy realms of decarbonization and energy security before and after the annexation of Crimea in 2014

Paegle, Jana January 2022 (has links)
How the EU frames Russia before and after the Crimean annexation betters our understanding of the motives and incentives behind a securitized unanimity in EU energy policy and decarbonization given previous internal dissensus. Europe’s energy transition and security policy is contingent upon Russian relations, considering its gas dependency. Given the 2022 Ukrainian invasion, studying past rhetorical change instigated within the EU is relevant, using the 2014 annexation as a potential catalyst. Russian energy flows reaching the EU are decreasingly predictable since they pass through key transit states like Ukraine. An overview of recent EU-Russian normative trajectories becomes appropriate as the EU tackles an energy crisis and is interconnected with an unreliable energy provider. Complex interdependence is used to explain the EU’s framing of Russia in energy relations, where mutual dependence, vulnerability and sensitivity to policy change define the states’ well-being, as postulated by Keohane and Nye. Marco Siddi’s conflict-cooperation dichotomy on the Russian Other supplements the framing analysis. An abductive coding approach forms the methodology, where the chosen material may inform the codes, alongside conceptual themes generated beforehand. The frames are applied to EU-parliamentary policy briefings, commission frameworks and bilateral EU-Russian roadmaps spanning between 2011-2016 with three yielded frames: ‘Commercial ties and sunk costs’, ‘Jeopardized security order’, and ‘Fossil-bound authoritarianism’. These frames are divided into pre-and post-annexation sections. The outcome points to attitude shifts in the EU, from perceiving Russia as a Cooperative Other to an Antagonistic Other. This manifests itself within energy security realms and partly in decarbonization. All three frames imply an EU-Russian bilateral relationship entrenched with sunk costs and commitments—with ideological rifts widening in energy security where the EU frames Russia as a normative and contractual violator. The changed framing of Russia may thus help explain how EU energy policy experienced recent change.
6

Geospatial Factors Affecting Equitable US Residential Heating Electrification

Kelsey A Biscocho (15339286) 22 April 2023 (has links)
<p>The heating sector accounts for almost half of total global energy consumption, with only 1/10th of heat produced from renewables. The adoption and technological advancement of heat pumps is key to electrifying heating, introducing more renewable sources, and decreasing energy expenditure. However, a range of complex barriers–including upfront costs, electricity costs, outdoor temperature, and building characteristics–hinder widespread heat pump adoption. High- resolution temporal and geospatial analysis is a powerful tool for understanding the patterns of such barriers, improving discernment of issues specific to certain populations. This project characterizes different heat pump technologies’ effects on residential energy use and expenditure with a high-resolution linear regression model of energy demand. We constructed linear regression efficiency models for two types of market-available heat pumps, characterized by refrigerant type and compressor type. With the thermal comfort energy demand estimates and estimated heat pump efficiency, we calculated the census tract, hourly-level energy demand in a 100% heat pump adoption case. We obtained these energy demand estimates for the states of Colorado and California–chosen due to their diverse climates and demographics–and used these energy demand estimates to calculate heat pump cost, electricity grid emissions, and energy burden. We also performed a case study comparison with actual heat pump energy consumption data for a household in West Lafayette, Indiana. </p> <p><br></p> <p>We found that heat pumps reduce total heating energy consumption and overall energy consumption for nearly all census tracts in both Colorado and California. In addition, for heating and overall energy consumption, our market average R410A heat pump model has the lower total variable cost in all census tracts relative to our R32 heat pump model. For cooling energy consumption, the R32 heat pump operates at a lower total variable cost than the R410A heat pump in most census tracts. Heat pumps tend to decrease average energy burden—percentage of household income dedicated to energy expenditure—in the less population-dense areas of both states. However, heat pump adoption leads to increased energy burden within cities. In comparison to our case study West Lafayette household, we obtained a relative root mean squared error for daily energy consumption of 28%, which is higher than studies using detailed engineering models at a single household-level but lower than studies using building simulation models. </p>
7

Effective Stakeholder Communication for Scope 3 Greenhouse Gas Emissions Abatement along the Supply Chain in the Food Retailing Sector : A Leadership Perspective

Niefer, Christina, Machold, Leonie January 2022 (has links)
The food retail industry's Scope 3 GHG emissions significantly contribute to global GHG emissions. Furthermore, it is widely acknowledged that a company's leadership style and effective stakeholder communication are critical for GHG abatement. Nevertheless, research on stakeholder communicationto persuade them to become more active in a company's sustainability process beyond current regulations is scarce. Based on a qualitative study on a case company, the thesis aims to underline the importance of effective stakeholder communication and leadership in the decarbonization process, focusing on Scope 3 GHG emissions of the company’s own brands upstream supply chain in the field of animal products. It examines and identifies communication hinders and drivers that can be influencedby leadership. Furthermore, measures of how to improve stakeholder communication along the upstream supply chain for practitioners are developed. Conclusively, the thesis displays that stakeholder communication is important due to the complexity of Scope 3 GHG emission reporting and the lack of a common language among stakeholders. It is further confirmed that leadership is key to eliminating stakeholder communication barriers. Most barriers have been identified due to inconsistent communication, making communication the primary motivator for Scope 3 GHG emission reporting. Finally, measures to improve stakeholder communication and thus Scope 3 GHG emission reporting for Company X’s in the Austrian food retail sector are presented. Moreover, the necessity for joint governmental regulations to reach climate targets set by the Paris Agreement and the SBTi is highly emphasized. As a final step, theoretical contributions, as well as directions for future research, are identified.
8

Integrated optimization based modeling and assessment for better building energy efficiency

Tahmasebi, Mostafa 02 June 2023 (has links)
No description available.
9

Digital twinning for ports : from characterization to operations’ modelling

Klar, Robert January 2024 (has links)
Ports are actively pursuing greater operational efficiency to effectively handle the increasing global flow of goods, while striving to improve the energy efficiency of their operations to comply with new environmental regulations. As a result, innovation-leading ports have begun to recognize the potential of digital twins to overview, coordinate and optimize port processes, resulting in energy savings, and reductions of costs and of CO2 emissions. While digital twins have gained momentum in other domains such as smart manufacturing and aerospace, their adoption in ports has been comparatively slow. This can be explained, among other things, by the multi-stakeholder nature of the port and the high complexity of the often interconnected port processes. Thus, this thesis, grounded in the context of ports, discusses what constitutes a digital twin, proposes characteristics to assess the maturity of existing digital twins, and introduces and evaluates mathematical models to support a key port process, which can be used as components of a digital twin for the port. The thesis is composed of three papers:  Paper 1 is based on an extensive literature review, through which digital twins among different domains are studied in depth in order to transfer insights from these to the port domain. The resulting discussion of what constitutes a port’s digital twin and the requirements that a port’s digital twin must fulfil, together with a discussion of use cases of how port digital twins can contribute to energy savings, form the basis of Paper 1.  Paper 2 discusses how digital twins’ maturity can be assessed within six maturity levels and presents milestones for their implementation. Notably, Interoperability is identified as the highest maturity level, as the numerous stakeholders and their respective digital twins must work together to reach a coordinated system of systems performance. Using this assessment demonstrates that only a few innovation-leading ports have developed sophisticated digital twinning solutions so far.  Paper 3 is dedicated to coordinating container retrieval with stacking, combining two key port operations. Thus, it can present a key modeling component of a port digital twin, considering jointly the goals of reducing the energy demanding crane movements, as well as keeping schedules tight to avoid port congestion issues. This is directly reflecting the potentially conflicting perspectives of different stakeholders in the port context. The provided optimization model and algorithm show that jointly addressing both problems may lead to a reduced efficiency of both individual objectives, but from a systems perspective, leads to a higher overall port efficiency. / Hamnar strävar aktivt efter ökad operativ effektivitet för att hantera den ökande globala varuflödet, samtidigt som de strävar efter att förbättra energieffektiviteten. Som ett resultat har ledande hamnar börjat se potentialen hos digitala tvillingar för att skapa överblick samt koordinera och optimera processer i hamnen. Målet med användningen av digitala tvillingar är energibesparingar samt minskning av kostnader och CO2-utsläpp. Medan digitala tvillingar har använts inom andra områden såsom tillverknings-, flyg- och rymdindustrin, har införandet i hamnar varit jämförelsevist långsamt. Detta kan förklaras, bland annat, av hamnens många olika involverade aktörer och den höga komplexiteten i de ofta sammanlänkade hamnprocesserna. Därför fokuserar denna avhandling, med utgångspunkt i hamnkontexten, vad som utgör en digital tvilling, presenterar egenskaper för olika mognadsnivåer hos befintliga digitala tvillingar, och introducerar samt utvärderar matematiska modeller som kan bli delkomponenter i en digital tvilling för hamnen. Avhandlingen består av tre artiklar: Artikel 1 bygger på en omfattande litteraturöversikt, inom vilken digitala tvillingar för olika områden studeras ingående för att överföra insikter från dessa till hamndomänen. Detta resulterar i en presentation av vad som utgör en hamns digitala tvilling och de krav som en hamns digitala tvilling måste uppfylla, tillsammans med en diskussion om möjliga sett på vilka hur hamnens digitala tvillingar kan bidra till energibesparingar. Artikel 2 presenterar ett ramverk för hur mognaden hos digitala tvillingar kan bedömas baserat på sex mognadsnivåer och presenterar milstolpar för deras implementering. Noterbart är att interoperabilitet identifieras som den högsta mognadsnivån, eftersom de många intressenterna och deras respektive digitala tvillingar måste koordineras för att nå en fungerande system-av-systemnviå. Genom att använda denna bedömning visar det sig att endast några få innovationsledande hamnar hittills har utvecklat sofistikerade digitala tvillinglösningar. Artikel 3 fokuserar på koordinering av containerupphämtning koordinerat med staplings effektivitet, två viktiga hamnaktivieter. Därför representerar dessa en viktig modelleringskomponent i en hamns digitala tvilling, med beaktande av målen att minska de energikrävande kranrörelse, samt behovet av att hålla planerade tider för att undvika trängsel och väntan. Detta speglar direkt de potentiellt konfliktfyllda perspektiven hos olika intressenter i hamnkontexten. Den utvecklade optimeringsmodellen och algoritmen visar att gemensam hantering av båda dessa problemen kan leda till en minskad effektivitet för de respektive individuella målen, men en ökad effektivitet från ett systemperspektiv för hamnen som helhet.
10

Decarbonization of Freight Transport at a Manufacturing Company : A Case Study of the International Manufacturer Rosemount Tank Radar AB

Jönsson, Ellen, Gullberg, Gilbert January 2021 (has links)
International manufacturing companies are shipping goods worldwide, resulting in interorganizational freight transportation where customers, suppliers, and logistics partners are involved in the transportation processes. This interorganizational nature of freight transport emissions has made them difficult to address, as they can be seen as not being connected to only one single company’s decisions. With the relevancy, consciousness, and interest of going greener being on the rise on a global level, many studies have made a call for a wider perspective on how manufacturing companies can work with reducing Carbon Dioxide (CO2) emissions from transport related to their business. This thesis addresses that call, and the research purpose of this thesis is to explore how a manufacturing company can achieve continuous and controlled reduction of CO2 emissions from freight transport. This study develops a framework in support of decarbonizing freight transport at a manufacturing company, through the adapting of Green Supply Chain Management (GSCM) activities, enabled by Strategy and Management Control Systems (MCSs). In sum, it is explored how a manufacturing company can adapt GSCM activities for decarbonization of freight transport as part of a decarbonization strategy, that is implemented and sustained within the company through MCSs. This master thesis studies the case company Rosemount Tank Radar AB, a Sweden-based manufacturer of measurement instrumentation with high levels of export. To find the relevant strategy and management control concepts and theories, a literature study was first conducted. Based on this literature study, a case study of the company was then performed. Following the case study, case findings were analyzed and related to the concepts and theories found in the literature study, leading to the final framework. The framework constitutes the overall conclusion, and a mapping of the analysis on how manufacturing companies can reduce their CO2 emissions from freight transport through the approach based on GSCM, decarbonization strategy, and MCSs. The framework gathers identified decarbonization strategy scopes for greener transports found within the research field of GSCM and the case study. These decarbonization strategy scopes are then set in relation to the identified strategy and control management concepts and tools, that support efficient and tangible implementation of the decarbonization strategy. On a practical level, the framework developed in this thesis is suggested to bring a foundation for discussions among supply chain managers at manufacturing companies that are looking to define or redefine their decarbonization strategy in order make their freight transport greener. As the case study findings of this master thesis also proposes, greener supply chain transport practices can lead to cost savings and better customer experiences, in addition to reducing CO2 emissions.

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