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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.
11

The value of design in reducing energy use and CO2-e impact over the life cycle of a detached dwelling in a temperate climate

Henriksen, Janet Elizabeth January 2006 (has links)
Masters Research - Master of Architecture (M Arch) / This thesis aims to quantitatively evaluate the impact of design decisions on the life cycle energy use and the resultant carbon dioxide equivalent gas (CO2-e) emissions of a house. It will compare the modelled life cycle impacts of three architects’ house designs in a temperate zone. It will suggest that the impact of a dwelling’s life and death is dependent on the decisions of the designer at its conception. Research into energy use in buildings previously has focused on two aspects: the embodied energy in materials used in construction and in the energy used to heat and cool a building. This dichotomy is also evident in studies of CO2-e impact where the argument previously focused on the relative importance of embodied impact versus operation impact. The debate was further obscured by a lack of differentiation between energy use and CO2-e impact as issues. It is proposed that a designer’s decisions will affect the energy used and CO2-e impact in the entire life of a building, both embodied and in operation. A life cycle analysis approach is developed from the perspective of a designer in a structured way, to form a hybrid framework for a holistic accounting process to assist design decision-making. Computer modelling programs are used and the results evaluated in the context of a modelled lifestyle. The BHP Steel LISA program, which assesses the impact of the materials used, is linked to NatHERS, a program used to rate energy requirement. In addition new spreadsheet based programs have been developed to model the site construction component of the life cycle, and the renovation component of a lifecycle. Also a spreadsheet program has been developed to convert the energy requirement output values from NatHERS to the number of hours a design is outside a defined temperature range. This allows an appliance to be modelled. The mental framework and method presented allows detailed analysis of design decisions. This method reduces the inherent complexity created in the design process when a designer desires to minimise energy use and CO2-e impact of a dwelling in a temperate climate. The method quantifies the difference in energy use and impact between specific design decisions in a life cycle. The quantified difference between specific design decisions is introduced as a concept and called the ‘D-value’. The difference (the D-value) between design options for specific combination of materials showed that design decisions may have significant impact over a life cycle. Energy use and CO2-e impact, though related, are shown to be two separate issues requiring a ‘both/and’ design approach.
12

Environmentální program restaurace McDonald's a zhodnocení efektivity programu ve vybrané provozovně

Klučková, Martina January 2012 (has links)
No description available.
13

Isoleringsmaterials påverkan på LCA och LCC i prefabricerade småhus / The impact of insulation materials on LCA and LCC in prefabricated houses

Georges, Steve, Larsson, Oskar January 2020 (has links)
Syfte: Syftet var att undersöka huruvida olika isoleringsmaterial inom byggsektorn påverkar CO2-utsläppen, kostnaden och köldbryggor i småhus. Detta utfördes för att belysa vilka effekter det medföra kortsiktigt och långsiktigt för både byggföretagen samt för klimatet. Metod: Metoderna som användes var litteraturstudie, dokumentanalys och fallstudie. Resultat: Resultaten från empirin visade att isoleringsmaterialet fick relativt stora konsekvenser för de totala energiförlusterna. Detta genom att köldbryggorna och U-värdenas storlek förändras medan areor och längderna på köldbryggorna är konstanta. Skillnaderna blir tydligare ju större area huset har (inklusive antal våningar) och det ger i de flesta fall även upphov till längre köldbryggor. Resultatet visade att cellulosa hade det bästa LCC-värdet medan aerogel hade det sämsta LCC-värde, aerogel var cirka 790% värre än cellulosa. Aerogel hade lägst koldioxidutsläpp vid utsläpp från el som bedriver huset medans mineralull, cellplast, cellulosa släpper ut cirka 10% mer än aerogel. Vid isoleringsmaterialproduktion släpper aerogel mest koldioxid och cellulosan absorberar koldioxid.   Konsekvenser: Isoleringsmaterialet har en stor inverkan på energiförlusterna i småhus. Det främsta skälet till att välja ett bättre isoleringsmaterial är på grund av värmekonduktivitet, då det får miljömässiga och ekonomiska konsekvenser. Lägre energiförbrukning är positivt för miljön. Begränsningar: På grund av examensarbetets omfattning begränsades undersökningen till småhus som är stationerade i Sverige. Det medförde att studien anpassades efter krav som återfinns I BBR (Boverkets Byggregler). Beräkningarna och värden för köldbryggorna är endast utförda teoretiskt, d. v. s ingen uppföljning sker eftersom tiden och resurserna inte är tillräckliga. Nyckelord: Aerogel, cellplast, cellulosa, energiförluster, energitransmission, hållbart byggande isoleringsmaterial, långsiktigt byggande, köldbryggor, mineralull, polyuretan, / Purpose: The purpose was to analyze to which degree different insulation materials affected the, CO2-emissions, cost and thermal bridges in houses. This was due to the fact that we wanted to highlight the effects it brought in the long and short run for both the building companies but also for the environment. Method: The methods used was literature studies, document analysis and case study. Findings: The results from the empiricism showed that the insulations material had relatively large consequences for the total energy losses. This due to the thermal bridges and the U-values size change while the areas and the lengths of the thermal bridges remain constant. The differences become more distinct with larger areas on the houses (including the amount of building floors) and usually result in longer thermal bridges. The results of the empirical study showed that cellulose had the best LCC value while aerogel had the worst LCC value, aerogel was about 790% worse than cellulose. Aerogel had the best carbon dioxide emissions when emitted from electricity while mineral wool, cellular plastic, cellulose emitted about 10% more than aerogel. In insulating material production, aerogel releases most carbon dioxide and the cellulose absorb carbon dioxide. Implications: The insulation material does have a large impact on the energy transmission in houses. There is more than one reason to choose a better insulation material, mainly because of environmental and economic reasons. Less energy consumption is positive for the environment. Limitations: Due to the extent of the examination project this study was limited to houses stationed in Sweden. It resulted in the study being costumed to fit the requirements in Boverket national board of housing, building and planning. The calculations and the values of the thermal bridges are only calculated in theory. Keywords: Aerogel, cellulose, energy loss, insulation material, mineral wool, polyurethane, polystyrene, sustainable building, thermal bridges,
14

A Theoretical Model for Life Cycle Inventory Analysis using a Disaggregated Hybrid Methodology

Spivak, Alexander January 2011 (has links)
No description available.
15

Livscykelanalys av granulärt svavel respektive torv : Vilken produkt genererar minst utsläpp av växthusgaser?

Reinklou, Johan January 2016 (has links)
The purpose of this report was to investigate which of the two products peat and granular sulphur that generates the least greenhouse gas emissions. The study was performed by doing a comparative Life Cycle Assessment (LCA) on the two different products. To perform the LCA, a standard from the Swedish Standards Institute was used. Data to put into the calculation was obtained from both Umeå Energi, their contractors and different internet-sources. The data was then multiplied with specific emission factors to get the total emission of greenhouse gases, expressed as carbon dioxide equivalents. Since peat is considered both a fossil energy source and a renewable energy source two calculations were made in the case of peat production. Results showed that granular sulphur generated the least emissions (23.0), peat classified as a renewable energy source second most emissions (71.5) and peat classified as a fossil energy source by far the most emissions (978.2). The conclusion to be made by this study is that if only the emission of greenhouse gases are important when choosing a product, granular sulphur should be used. Key words: peat, greenhouse gases, LCA, sulphur.
16

Comparative Life Cycle Analysis for Value Recovery of Precious Metals and Rare Earth Elements from Electronic Waste

Zhen Li (6853490) 14 August 2019 (has links)
<div>There is an ever-increasing concern regarding electronic waste (e-waste), which is the fastest growing waste stream in the world. E-waste contains highly toxic materials such as halogenated flame retardants and heavy metals, as well as precious metals like gold, silver, and platinum. Its proper management and disposition are paramount. Incentivized by various legislations and the intrinsic value of critical metals inside, recycling of e-waste is becoming an attractive business opportunity that also benefits the environment. A novel electrochemical recovery (ER) process has been developed as a promising alternative to the existing pyrometallurgical and hydrometallurgical processes-based technologies to recover base metals, precious metals, and rare earth elements (REEs) from e-waste. Experimental results indicate that the ER process has lower chemical consumption, enhanced control, and reduced energy demand compared to the pyrometallurgical and the hydrometallurgical processes. To quantify and compare the environmental performances of the three technologies, life cycle analysis has been conducted. The baseline comparison used $1000 revenue from the e-waste recovery as a functional unit. Results show that the ER process outperforms the other two processes in almost all impact categories adopted in TRACI and ILCD while there is no clear winner between the hydrometallurgical and the pyrometallurgical processes. The life cycle analysis helped identify the significant inputs for different processes. The highest impactful input for the ER method is hydrochloric acid, and for the pyrometallurgical method is copper scrap, while for the hydrometallurgical method, it is hydrogen peroxide, an oxidizer that accelerates base metal extraction process that dominates the overall environmental footprint. Other than the baseline case, the environmental impacts of recovering REE from e-waste with different processes and from other method were studied. The results indicate REE recovered from e-waste has a lower environmental footprint than virgin extraction. Overall, the ER process has the lowest impacts on the environmental side among the three e-waste treatment processes. The environmental viability of the ER process warrants the further development of the ER process at industrial scale. <br></div><div><br></div>
17

A Comprehensive Method for the Selection of Sustainable Materials for Building Construction

Zhang, Yuxin 01 May 2012 (has links)
In the design phase of any building industry, appropriate material selection is critical for the entire project. A poor choice of material may affect the quality of the project, lead to high cost during the long term operation and maintenance phases, and even endangering humans and the environment. Since the inception of the United States Green Building Council (USGBC) in 1993, ¡°green¡± buildings have become a hot topic and people have become concerned about how sustainable their buildings are. In order to determine the level of sustainability in buildings, the Leadership in Energy and Environmental Design (LEED) has developed a rating system that has been established now as the common denominator in the industry. However, the LEED rating system simplifies, or even ignores, explicit considerations for Lifecycle Assessment (LCA) in determining the selection of building materials. This lack of explicit consideration for LCA does not permit a full assessment in determining how truly sustainable the chosen materials are. This research analyzes the factors impacting the selection of the green materials and reviews the current standards used in green material. It proposes a more comprehensive rating method for the green material selection illustrating its applicability through a case study analysis based on new WPI Sports and Recreation Center. It is expected that this study would contribute to a better understanding of the sustainable materials selection and can improve help to improving their long term performance in buildings.
18

Ett kreativt miljövetenskapligt analysverktyg – Tänk om...?

Olsson, Clara January 2020 (has links)
Allt högre krav ställs på designers att utveckla produkter som rör sig inom de planetära gränserna. Miljövetenskapliga analysverktyg som ska hjälpa designern att välja “rätt” i produktutveckling finns, exempelvis livscykelanalys, men används sällan av produktdesigners då de ofta är komplicerade, kostsamma och för expertinriktade (Vallet et. al. 2013). Om verktygen används är det ofta sent i designprocessen när många produktbeslut redan är tagna vilket försvårar möjligheten att påverka produktens miljöeffekt (Naturvårdsverket, 1999). Studien undersöker hur miljövetenskapliga analysverktyg kan komma in tidigare i en designprocess där fokus ligger på användarvänlighet för produktdesigners. Genom intervjuer med designers och litteraturstudier, ges ett designförslag. Designförslaget är ett problemformulerings-och idégenereringsverktyg i form av en “spelplan” på whiteboardark inspirerat av livscykelanalys, miljöeffektanalys och orsak-verkan diagram. Syftet med verktyget är att hjälpa designers att redan tidigt i problemformuleringen och initiala idégenereringen integrera dessa verktyg. Det kan hjälpa designprofessionen att hantera de nya förväntningarna på yrkesrollen, det behövs dock en närmare kontakt med användare och en tvärvetenskapligt arbetsgrupp för att säkerställa att verktyget passar in i designprocessen samt faktiskt genererar mer hållbara produkter. / There is an increasing demand on product designers to develop products that fits within the planetary boundaries. Environmental analysis tools are there to help but are often overseen and accused of being complicated, costly and expert oriented (Vallet et. al. 2013). These tools are also often used late in the design process when product decisions are already made, which makes it difficult to influence the products environmental impact (Naturvårdsverket, 1999). The study examines how environmental analysis tools can be integrated in the first phases of a design process using a user-centered design process with focus on product designers. Through interviews and litterature studies a design propsal is given. The design proposal is a problem formulating and idea generating tool that consist of a white board sheet with graphics and “game” rules. The design is based on life cycle analysis, environmental effekt analysis and causal loop diagram. The purpose is to help designers integrate these tools earlier in the design process. The tool may help the design profession to handle the new expectations of the professional role, however, a closer contact with users and an interdiciplinary working group might be needed to ensure that the tool fits in to the design process and actually genereates more sustainable products.
19

Update of the LCA-software WAMPS : Proposing new emission factors and investigating the implications / Uppdatering av LCA-verktyget WAMPS : Föreslå nya utsläppsfaktorer och undersöka konsekvenserna

Unsbo, Hanna January 2021 (has links)
In recent decades, life cycle assessment (LCA) has become a commonly used approach worldwide when studying environmental impacts linked to waste management systems. These systems are of a complex nature which includes everything from technical solutions, the environmental influence, and various stakeholders. To facilitate studies within this area of research, different LCA models are often utilised. WAMPS is a software specifically developed for assessing the environmental and economic impacts for a waste management system. During recent years, the work to bring the model up to date has begun as the software has not been modernised since it was developed in the early 2000s. The purpose of this degree project is to propose new emission factors for recycling and virgin production of glass, aluminium, steel, and plastic. In addition to this, the study intends to investigate how the implementation of the new figures may affect the results obtained in WAMPS.  To fulfil the purpose of the thesis, LCI datasets were collected for each material and evaluated according to three DQIs (Temporal representativeness, geographical representativeness, and documentation). New emission factors were developed based on the evaluation and discussions within the project group, to ensure that all relevant activities of the studied life cycles were included. The implications from implementing the new emission factors were investigated through a comparison with the old values. This was conducted through comparing the obtained results from WAMPS per one tonne of material as well as for a simple scenario.  The evaluation of the collected LCI data shows that many of the datasets represent average production in countries within Europe and that the data were generally older than five years old. The results show that the datasets were primarily well documented according to the criterion utilised in this study. Processes from EcoInvent were mainly used to develop the proposed emission factors. The implementation of the new emission factors in WAMPS resulted in significant change in potential environmental impact per tonne of material. Especially for the impact category photooxidation formation. For the scenario, the results indicated that a significant change in potential environmental burden is received when implementing the new emission factors. A reduction in total impact was obtained for all categories where eutrophication showed the largest absolute difference.  The developed emission factors are considered appropriate based on the design of this thesis. However, it is concluded that these have several limitations that are important to take into account if these were to be implemented in WAMPS in the future. In addition, it is considered established that an update may be considered reasonable based on the result obtained. / Under de senaste decennierna har livscykelanalys (LCA) blivit ett vanligt tillvägagångssätt världen över vid analyser av potentiella miljöeffekter kopplade till avfallshanteringssystem. Dessa system är av komplex natur och inkluderar allt från teknologiska lösningar, miljöpåverkan samt flera intressenter. För att underlätta dessa studier används idag ofta olika LCA-modeller. WAMPS är ett program som är särskilt utvecklad för att bedöma både miljömässiga- och ekonomiska konsekvenser kopplat till avfallshanteringssystem. Under de senaste åren har arbetet med att uppdatera modellen påbörjat eftersom programvaran inte har uppdaterats sedan början av 2000-talet. Syftet med detta examensarbete är att föreslå nya emissionsfaktorer för återvinning och jungfrulig produktion av glas, aluminium, stål, och plast. Utöver detta avser studien att studera hur implementeringen av de nya siffrorna inverkar på resultatet som erhålls i WAMPS.  För att uppfylla tesen av detta arbete samlades LCI data in för varje material och utvärderades enligt tre DQI:er (Temporal representativitet, geografisk representativitet och dokumentation). Nya utsläppsfaktorer utvecklades baserat på utvärderingen och genom diskussioner inom projektgruppen. Framförallt för att säkerhetsställa att alla relevanta aktiviteter i de studerade livscyklerna är inkluderade. Konsekvenserna av implementeringen av utsläppsfaktorerna undersöktes genom en jämförelse av resultat som erhölls i WAMPS då de nya samt de tidigare faktorerna nyttjas. Detta gjordes både per ton material samt genom ett enkelt scenario.  Utvärderingen av den insamlade LCI datan påvisar att många av dataseten representerar genomsnittlig produktion inom Europa och att datan generellt var insamlad för minst 5 år sedan. Resultatet påvisar att dataseten är väldokumenterad enlig indikatorn som ställts upp i denna studie. Främst användes processer från EcoInvent för att utveckla de nya emissionsfaktorerna. Implementeringen av emissionsfaktorerna i WAMPS resulterade i signifikanta skillnader i potentiell miljöpåverkan per ton material, främst för bildning av fotooxid. För fallet med scenariot indikerade studiens resultat att en betydande förändring av den potentiella miljöbelastningen erhålls när de nya utsläppsfaktorerna implementeras. Dessutom påvisades en minskning av miljöeffekterna för alla kategorier varav eutrofiering visade den största absoluta skillnaden.  Slutligen anses de utvecklade emissions faktorerna vara lämpliga utifrån utformningen av denna tes. Dock dras slutsatsen att dessa har flertalet begränsningar som är viktiga att ta i hänsyn ifall dessa implementeras i WAMPS i framtiden. Dessutom anses det vara fastställt att en fortsatt uppdatering kan anses rimlig utifrån det erhållna resultatet.
20

Sustainable Nanotechnology: Life Cycle Thinking in Gold Nanoparticle Production and Recycling

Pati, Paramjeet 01 September 2015 (has links)
Nanotechnology has enormous potential to transform a wide variety of sectors, e.g., energy, electronics, healthcare, and environmental sustainability. At the same time, there are concerns about the health and environmental impacts of nanotechnology and uncertainties about the fate and toxicity of nanomaterials. Life cycle assessment (LCA), a quantitative framework for evaluating the cumulative environmental impacts associated with all stages of a material or process, has emerged as a decision-support tool for analyzing the environmental burdens of nanotechnology. The objective of this research was to combine laboratory techniques with LCA modeling to reduce the life cycle impacts of gold nanoparticle (AuNP) production. The LCA studies were focused on three aspects of AuNP synthesis: 1) the use of bio-based ("green") reducing agents; 2) the potential for recycling gold from nanomaterial waste; and, 3) the reduction of the life cycle impacts of AuNP production by conducting the synthesis at reduced temperature. The LCA models developed for AuNPs can inform future nanotechnology-focused LCA studies. Comparative LCA showed that in some cases, the environmental impacts associated with green synthesis methods may be worse than those of conventional synthesis approaches. The main driver of the environmental burdens associated with AuNP synthesis is the large embodied energy of gold, and so-called green synthesis methods do not offset those impacts. In addition, the reaction yield, which is seldom reported in the literature for green synthesis of nanomaterials, was found to greatly influence the life cycle impacts of AuNP synthesis. Gold from nanomaterial waste was successfully recovered by using host-guest inclusion complex formation facilitated by alpha-cyclodextrin. This recycling approach involved room temperature conditions and did not require the toxic cyanide or mercury commonly used in the selective recovery of gold. A major advantage offered by this approach for selective gold recovery over conventional approaches is that the recovery does not involve the use of toxic cyanide or mercury. To reduce the energy footprint of citrate-reduced AuNP synthesis, the synthesis was conducted at room temperature. LCA models showed significant reduction in the energy footprint. The findings of this research can inform future LCAs of other nanomaterials. / Ph. D.

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