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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.
51

Life Cycle Impacts of Road Infrastructure : Assessment of energy use and greenhouse gas emissions

Miliutenko, Sofiia January 2012 (has links)
Road infrastructure is essential in the development of human society, but has both negative and positive impacts. Large amounts of money and natural resources are spent each year on its construction, operation and maintenance. Obviously, there is potentially significantenvironmental impact associated with these activities. Thus the need for integration of life cycle environmental impacts of road infrastructure into transport planning is currently being widely recognised on international and national level. However certain issues, such as energy use and greenhouse gas (GHG) emissions from the construction, maintenance and operation of road infrastructure, are rarely considered during the current transport planning process in Sweden and most other countries.This thesis examined energy use and GHG emissions for the whole life cycle (construction, operation, maintenance and end-of-life) of road infrastructure, with the aim of improving transport planning on both strategic and project level. Life Cycle Assessment (LCA) was applied to two selected case studies: LCA of a road tunnel and LCA of three methods for asphalt recycling and reuse: hot in-plant, hot in-place and reuse as unbound material. The impact categories selected for analysis were Cumulative Energy Demand (CED) and Global Warming Potential (GWP). Other methods used in the research included interviews and a literature review.The results of the first case study indicated that the operational phase of the tunnel contributed the highest share of CED and GWP throughout the tunnel’s life cycle. Construction of concrete tunnels had much higher CED and GWP per lane-metre than construction of rocktunnels. The results of the second case study showed that hot in-place recycling of asphalt gave slightly more net savings of GWP and CED than hot in-plant recycling. Asphalt reuse was less environmentally beneficial than either of these alternatives, resulting in no net savings of GWP and minor net savings of CED. Main sources of data uncertainty identified in the two case-studies included prediction of future electricity mix and inventory data for asphalt concrete.This thesis contributes to methodological development which will be useful to future infrastructure LCAs in terms of inventory data collection. It presents estimated amounts of energy use and GHG emissions associated with road infrastructure, on the example of roadtunnel and asphalt recycling. Operation of road infrastructure and production of construction materials are identified as the main priorities for decreasing GHG emissions and energy use during the life cycle of road infrastructure. It was concluded that the potential exists for significant decreases in GHG emissions and energy use associated with the road transport system if the entire life cycle of road infrastructure is taken into consideration from the very start of the policy-making process. / QC 20120229
52

Design of railway bridges considering LCA

Thiebault, Vincent January 2010 (has links)
Environmental awareness has strongly increased these last years, especially in the developed countries where societies have become increasingly preoccupied by the natural resource depletion and environmental degradation. At the same time, the increasing mass transportation demand throughout the European Union requires the development of new infrastructures. Life Cycle Assessment is increasingly used to provide environmental information for decision-makers, when a choice is to be made about the transportation mode to be implemented on a given route. In a life-cycle perspective, not only the environmental pressure of the operation of vehicles but also the burden from the infrastructure, in particular bridges as key links of the road and railway networks, has to be assessed when comparing transportation modes. Based on an extensive literature review, a simplified quantitative LCA is implemented in order to compare the environmental performance of two railway bridge designs. It is meant to be useful at an early stage in the design process, when no detailed information about the bridge is available, and when rough environmental estimations are needed. The Excel based model covers the entire life-cycle of the bridge, from raw material extraction to construction materials recycling and disposal. Various assumptions and omissions are made to narrow the scope of the analysis. For instance, processes that are found insignificant in the literature are omitted, and only a limited set of relevant emissions and impacts to the environment is considered. The model provides fully transparent results at the inventory and impact assessment level. The streamlined approach is tested by comparing the environmental burden throughout the life-cycle of a steel-concrete composite railway bridge on a single span, equipped with either a ballasted or a fixed concrete single track. The results show that the environmental impacts of the fixed track alternative are lower than that of the ballasted track alternative, for every impact categories. In a sustainable development perspective, it would thus have been preferable to install a fixed track over the bridge to reduce its overall impact on the environment by about 77%. The raw material phase is found decisive in the life-cycle of both alternatives. The frequency of the replacement of the track is identified as a key environmental parameter, since the road traffic emissions during bridge closure nearly overwhelmed the other life-cycle stages.
53

LCA of Microgrid System: a Case Study at ‘North-five Islands’ of Changshan Archipelago, China

Yuning, Jiang January 2019 (has links)
Microgrid can provide stable, clean, and sustainable electricity supply for remote places since it can operate on renewable energy sources and work isolated from the utility grid. This thesis evaluates the life cycle greenhouse gas (GHG) emissions of the microgrid system which is located at the ‘North-five Islands’ of Changshan archipelago in China. The existing electricity generation technologies of the microgrid system are wind turbine, PV system and diesel generators with the capacity of 2 MW, 300 kW and 2046 kW, respectively. The total demand of electricity (362.2 GWh) will be supplied by the wind turbine, PV system and diesel generators with 32.03%, 2.36% and 65.62%, respectively, if the microgrid system is required to supply the electricity demand for the ‘North-five Islands’ area alone under the islanded mode during 20 years lifespan. The thesis uses the Life Cycle Assessment (LCA) to evaluate the life cycle GHG emissions of the microgrid system. The life cycle stages of this study include: raw material extraction, manufacturing, transportation and operation. In order to assess the environmental benefits of the microgrid system, three electricity supply options – ‘microgrid electricity supply option’, ‘grid extension electricity supply option’, and ‘conventional fossil diesel generators electricity supply option’ are designed to evaluate the life cycle GHG emissions for supplying 20 years electricity demand (362.2 GWh) of the ‘Northfive Islands’. The results show that the life cycle GHG emissions of the ‘microgrid electricity supply option’ are 223.19 million kgCO2eq. Compared to the ‘grid extension electricity supply option’ and ‘conventional fossil diesel generators electricity supply option’, the net savings of the GHG emissions are 70.56 and 112.18 million kgCO2eq, respectively. It mainly results from the differences of the electricity supply methods of the three electricity supply options. For the ‘microgrid electricity supply option’ itself, the operation stage takes the most responsibility of the life cycle GHG emissions with 97.6%. The raw material extraction, manufacturing and transportation stages account for 1.93%, 0.44% and 0.026%, respectively. For the system components of the microgrid system, the wind turbine, PV system, diesel generators, energy storage system, and cables account for 0.34%, 0.18%, 97.75%, 0.60%, and 1.12%, respectively, of the microgrid system’s life cycle GHG emissions. The thesis conducts the sensitivity analysis of diesel burn rate efficiency (L/kWh) of the microgrid system’s diesel generators due to a large quantity (60.84 million L) of diesel consumption by the diesel generators during 20 years operation time. According to the results of the sensitivity analysis, the diesel burn rate efficiency can directly impact the diesel consumption of the diesel generators, and consequently has a significant impact on the life cycle GHG emissions of the ‘North-five Islands’ microgrid system. Since the diesel burn rate efficiency represents the amount of diesel consumption, this results highlight the significance of any factors that affect the diesel consumption (e.g. quantity of diesel, temperature, altitude, etc.), in affecting the life cycle GHG emissions of the ‘North-five Islands’ microgrid system. In addition, the thesis performers the sensitivity analysis of renewable energy (wind and solar energy in specific) fraction of the studied microgrid system because of the huge potential of available renewable energy (63.65 MW of wind turbines) nearby the microgrid system. The results of the sensitivity analysis show that the life cycle GHG emissions of the microgrid system decrease linearly with the increase of wind and solar energy fraction. Particularly, the life cycle GHG emissions of the microgrid system decrease 1.46% (3.26 million kgCO2eq) and 1.37% (3.05 million kgCO2eq) with an increase of 1% in wind and solar energy, respectively.
54

Wood's Potential as an Eco-Friendly Building Material: A Comparative Study of Wood and Steel Columns in Reducing Energy Consumption and Carbon Emissions in Construction

Ibrahim, Shuruq January 2023 (has links)
The building sector contributes significantly to carbon dioxide (CO2) due to the high energy use in building material production. One of the most critical concerns the World Summit on Sustainable Development must address is saving energy. In order to reduce CO2 emissions and their impact on the climate, strategies such as reducing energy demand, increasing efficiency, and using renewable resources instead of fossil fuels need to be implemented. This study was conducted through a mix of qualitative and quantitative methods to examine the possibility of lowering energy use and emissions in columns. The main purpose is to examine the potential environmental impact and energy use using a lifecycle assessment (LCA) approach. Steel production contributes significantly to climate change because it uses a lot of energy and produces many greenhouse gases. In Sweden, the steel industry uses coal as the main fuel, as shown from the data collected. Various studies explore the potential for reducing greenhouse gas (GHG) emissions and improving carbon sinks, such as taking measures in the building, energy supply, and forestry industries. This study concludes that buildings can be designed to be more energy-efficient, with better materials that are energy-efficient and lower carbon emissions. Material substitution can reduce energy use and carbon emissions. The replacement of steel with wood in construction can significantly reduce carbon emissions. The research findings indicate that an effective strategy to enhance the sustainability of buildings during the production phase is to reduce energy consumption and carbon emissions by incorporating wood as a primary building material.
55

Integrated Life Cycle Assessment (LCA) to Building Information Modelling (BIM) / Integrerad Livscykelanalys Inom Building Information Modelling

Köseci, Firat Can January 2018 (has links)
Building Information Modelling (BIM) and Life Cycle Assessment (LCA) are at the core of construction projects. LCA is one of the key elements of sustainability in the construction projects and an improved LCA process can be achieved through the adoption of BIM. Exploring the characteristics of a BIM-based LCA process from the different perspectives of interoperability and identifying the effects of adopting regionally different EPD databases are significant.  The LCA add-in tools, One Click LCA and Tally, have been selected to identify the differences in the LCA results caused by adopting regionally different Environmental Product Declaration (EPD) databases. To observe the differences in the LCA results, the LCA processes were run through the LCA add-in tools. The input data, the system boundaries and the LCA scope were kept the same for the LCA processes. The LCA results were produced through the integrated LCA add-in tools. The GWP values in manufacturing module, produced by One Click LCA, were embedded into the Solibri model of Akademiska Sjukhuset project. Value level of interoperability in the BIM-based LCA processes was detected and analyzed according to the interaction types that were obtained between the LCA add-in tools and the BIM software. Obstacles in increasing the value level of interoperability to a higher level in today’s BIM-based LCA processes were also focused. Furthermore, the benefits and drawbacks of the BIM-based LCA processes were identified. At last, the differences between BIM-based LCA and traditional LCA process were identified along with future possibilities. It was observed that adopting regionally different EPD databases has significant effects on the LCA results. The semantic detail level of the BIM model and the data extraction quality came to the forefront in identifying the benefits and drawbacks. The interaction types in the studied BIM-based LCA processes were identified as “Collaboration” interaction type. Accordingly, the value level of interoperability in both BIM-based LCA processes was obtained as the high level of value innovation along with efficiency and differentiation. Moreover, the convenience of use, time and resource efficiency and improved accuracy obtained through the BIM-based LCA processes were concluded as some of the major differences from the traditional LCA processes. / BIM (Building Information Modelling) och LCA (Life Cycle Assessment) ligger i kärnan av byggprojekt. LCA är ett nyckelverktyg för hållbarhetsarbete i byggbranschen och en förbättrad LCA-process kan uppnås i och med att tillämpa BIM-verktyg. BIM bjuder på många nyttor däremot detta arbete fokuserar på nyttan som BIM kan ge till LCA-processen. Därmed är forskning på grunden till Bim-baserad LCA-process och datas integrations- och konverteringsförmågan ytterst viktiga för detta arbete. LCA-verktyg One Click LCA och Tally och dess tillägg till CAD-mjukvaror har utvalts för att jämföra resultat vars indata är baserat på olika EPD-databaser (Environmental Product Declaration). För att iaktta skillnader i LCA-resultat, har LCA-processen gjorts med dessa LCA-verkytg. Indata, systemgränser och LCA-definitionsområde var samma för båda LCA-processer. LCA-resultat producerat av båda LCA-verktyg har jämförts utifrån klimatavtrycksperspektiv (Global Warming Potential) för materialframtagandesskede. One Click LCAs GWP-värden har importerats i en Solibri-modell för projektet. Slutligen har LCA-resultat av en Bim-baserad process jämförts med resultat av en klassisk LCA process. Påverkan av geografiskt anpassade EPD-databaser är avgörande för LCA-resultat. Materialframtagandesskede har störst miljöpåverkan i förhållande till andra livsskede. Semantisk detaljnivå av Solibri-modellen är avgörande för identifiering av för- och nackdelar av datas integrations- och konverteringsförmågan. Datainteraktionstyper studerade i BIM-baserade LCA-processer klassas som kollaborativ interaktionstyp. Integrations- och konverteringsförmåga av både BIM-baserade LCA-processer utvärderades på en hög nivå gällande förbättrade resultat, effektivitet och resultatkännslighet. Utöver dessa har BIM-baserade LCA-processer en förbättrad användbarhet och är mer tid- och resurseffektiva, vilka är huvudskillnader från en LCA-process utfört på klassiskt sätt.
56

Comparative Life Cycle Assessment of Cardiac Monitoring Devices : A Case Study

Kokare, Samruddha January 2020 (has links)
Current cardiac monitoring devices are rigid, bulky, and integrate poorly with the human skin, obstructing health monitoring for longer periods. With the miniaturization of electronics, soft and stretchable polymer substrate-based cardiac monitoring device is being developed at Mycronic AB to overcome the aforementioned issues and replacing the traditional rigid electronics-based cardiac monitoring devices. Manufacturing of stretchable cardiac monitoring device includes new materials and manufacturing techniques as well as different end-of-life treatments. The sustainability of this kind of stretchable device is often enquired by curious customers and environment enthusiasts. Without a comprehensive scientific study on the environmental performance of this device, it is difficult for the manufacturer to answer such inquiries. Hence, this study aims to carry out a comparative Life Cycle Assessment (LCA) of rigid and stretchable cardiac monitoring devices. The LCA for both the devices was based on ISO 14044:2006 standards. The impact assessment method used was ReCiPe 2016 (Hierarchist). The LCA results showed that the stretchable cardiac monitor had significantly lower impacts than its rigid counterpart. Lower usage of Printed Circuit Board (PCB) in the stretchable device was the main reason for its better environmental performance. The PCB was identified as the major environmental hotspot in both the devices. / Nuvarande hjärtövervakningsanordningar är styva, skrymmande och dåligt integrerade med människans hud och hindrar övervakning under längre perioder. Inom ramen för det europeiska forskingsprojektet SINTEC har Mycronic bidragit till att utveckla en ny design och tillverkningsmetod för en mjuk och töjbar polymersubstratbaserad övervakningsanordning för att övervinna de ovan nämnda hindren med de traditionella alternativ. Tillverkning av töjbar hjärtövervakningsanordning inkluderar nya material och tillverkningstekniker som ger en ökad hållbarhet som ofta efterfrågas av nyfikna kunder och miljöentusiaster. Men utan en omfattande vetenskaplig studie om enhetens miljöprestanda är det dock svårt för tillverkaren att besvara sådana frågor, och därför syftar denna studie till att utföra en jämförande livscykelanalys (LCA) av styva och töjbara hjärtövervakningsanordningar. LCA för båda enheterna baseras på ISO 14044: 2006-standarder. Den konsekvensbedömning som användes var ReCiPe 2016 (Hierarchist). LCA-resultaten visade att den töjbara hjärtmonitorn hade signifikant lägre påverkan än dess styva motsvarighet. Lägre användning av kretskort (PCB) i den töjbara enheten var den främsta anledningen till dess bättre miljöprestanda och just PCB identifierades som den viktigaste miljöhotspoten i båda enheterna.
57

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.
58

Life Cycle Assessment of Lettuce Production Systems : A Case Study Performed at Hollbium / Livscykelanalys av produktionssystem för sallad : En fallstudie utförd vid Hollbium

Mujkic, Selma, Andakudi Kesavan, Kaushik Narasimhan January 2020 (has links)
Agriculture is one of the most carbon-intensive sectors in today’s world. With demand for food soaring to feed an ever-increasing population, many methods are employed to produce food, ranging from open-field to greenhouse systems. However, due to their large environmental footprint, urban agriculture methods such as soilless culture systems are increasingly becoming a preferred method for food production. A case study has been performed at Hollbium in Stockholm, Sweden for the purpose of evaluating potential environmental impacts of Hollbium Loop, a vertical hydroponic system used for food production. This is achieved by carrying out a stand-alone assessment of Hollbium Loop, to identify potential environmental hotspots over the product’s lifetime of 10 years. Furthermore, Hollbium Loop’s system is compared to the production of lettuce in a horizontal open-field, a greenhouse farming system and nutrient film technique located in Spain, to identify potential trade-offs. Attributional life cycle assessment (ALCA) has been employed as a methodology with an explicit focus on eight impact categories at a midpoint level. The results of the study indicate that hotspots of environmental impacts in Hollbium Loop’s life cycle are due to the use of an internal combustion engine vehicle for maintenance, production of electronic components and the consumption of electricity in the use phase. In contrast, the results from the comparative scenarios indicated that Hollbium Loop from a life cycle perspective had the highest impacts under all impact categories in relation to the other three systems of food production. When the distance for transportation within the maintenance phase is reduced to a reasonable figure, Hollbium Loop no longer had the highest impacts within global warming and fossil resource scarcity, showing that the distance traversed plays a key role in mitigating the impacts. Other aspects and assumptions are also analyzed further using a sensitivity analysis, which shows that there is scope for decreasing Hollbium Loop’s environmental footprint. It is therefore recommended that Hollbium puts its efforts into optimizing the distance and modes of transport utilized and increasing the outer frame thickness of the Loop to make it sturdy and robust. Finally, it is also advised to increase the Loop’s vertical length to increase the yield per cycle, thereby reducing the overall impacts per kilogram of lettuce produced. / Jordbruket är en av de mest kolintensiva sektorerna i dagens värld. Med en efterfrågan på livsmedel som stiger för att föda en ständigt ökande befolkning, används många metoder för att producera livsmedel. Dessa metoder omfattar allt från öppna fält till växthussystem. På grund av deras stora miljöpåverkan blir emellertid stadsnära jordbruksmetoder, såsom system för hydroponiska odlingar (odlingar utanför jorden) en alltmer föredragen metod för livsmedelsproduktion. En fallstudie har genomförts hos Hollbium i Stockholm, Sverige med syfte att genomföra en utvärdering av den potentiella miljöpåverkan för Hollbium Loop, ett vertikalt hydroponiskt system som används för livsmedelsproduktion. Detta uppnås genom att först utföra en fristående bedömning av Hollbium Loop och på så sätt identifiera potentiella riskområden under produktens livslängd på tio år. Dessutom jämförs Hollbium Loops system med produktionen av sallad i ett horisontellt öppet fält, ett växthusodlingssystem och en näringsfilmsteknik i Spanien för att identifiera potentiella avvägningar. Attributiv livscykelanalys (ALCA) har använts som metod med ett tydligt fokus på åtta karakteriseringsfaktorer för mittpunkt. Resultaten i studien indikerar att riskområden för miljöpåverkan i Hollbium Loops livscykel beror på en användning av fordon med förbränningsmotor i underhållsfasen, produktion av elektroniska komponenter och elförbrukning i användningsfasen. Däremot visade resultaten från de jämförande scenarierna att Hollbium Loop ur ett livscykelperspektiv har den högsta miljöpåverkan i alla påverkanskategorier i jämförelse med de tre andra systemen för livsmedelsproduktion. När avståndet för transport inom underhållsfasen reduceras till en rimlig nivå så hade Hollbium Loop inte längre den högsta påverkan inom global uppvärmning och knappa fossila resurser, vilket visar att det avståndet spelar en nyckelroll för att mildra effekterna. Andra aspekter och antaganden analyseras också vidare med hjälp av en känslighetsanalys, som således visar att det finns utrymme för att minska Hollbium Loops miljöavtryck. Det rekommenderas därför att Hollbium satsar på att optimera avståndet och de transportsätt som används, men att även öka tjockleken av den yttre ramen för att göra den stabil och robust. Slutligen rekommenderas det även att öka systemets vertikala längd för att öka avkastning och därmed minska de totala effekterna per kilo producerad sallad.
59

Environmental Impacts of ICT: Present and Future

Arushanyan, Yevgeniya January 2016 (has links)
ICT is developing rapidly and is playing an increasingly important role in society. High expectations are placed on ICT in relation to sustainable development. In order to provide basis for decision-making and ensure that ICT is used in the best possible way for enabling sustainable development, the sustainability impacts of ICT need to be studied. This thesis aims to provide new knowledge on the environmental impacts related to ICT, to explore the potential of ICT to contribute to sustainability, and discuss ways of assessing environmental impacts of ICT. In order to fulfill the aim a literature review of existing LCA studies of ICT was done, an LCA case study of printed and online media was performed, a methodological framework for sustainability assessment of scenarios was developed and then applied for environmental assessment of future ICT societies. The results show that manufacturing and use phase are the life cycle stages contributing the most to the ICT environmental impacts. For online newspapers online distribution and content production may give significant contribution to the overall impact. User behavior was observed to be crucial for the results of comparisons of ICT solutions with their traditional counterparts. The following key issues were concluded to influence the environmental risks and opportunities in future ICT societies: energy mix, economic conditions, life styles, technology, and environmental ambitions, incentives and regulation. The potential of ICT for sustainability is affected by these key issues. A new methodological framework (SAFS) was developed for the assessment of future scenarios (societal level). Life cycle assessment (LCA) was used for assessment on a product level. Application of both methods, their benefits, drawbacks, and challenges of assessment were discussed. Both types of assessments were concluded to be important to support decision-making. / Utveckligen inom informations- och kommunikationsteknologi (IKT) sker snabbt och IKT spelar en allt viktigare roll i samhället. Samtidigt finns stora samhällsutmaningar inom hållbarhetsområdet, och ganska höga förväntningar ställs på IKT att kunna bidra till en hållbar utveckling. Vissa studier hävdar att IKT kan spela en avgörande roll för att stödja olika hållbarhetsstrategier och att IKT kan möjliggöra övergången till en mindre resursintensiv ekonomi. För att ge underlag för beslutsfattande och stödja att IKT används på bästa sätt för att möjliggöra hållbar utveckling, behöver hållbarhetseffekter av IKT studeras. När det gäller miljöpåverkan måste både negativa och positiva, direkta och indirekta effekter beaktas. Det är viktigt att förstå miljöpåverkan genom hela livscykeln för specifika enskilda IKT-lösningar men också att studera IKTs sammanvägda effekter i en mer övergripande kontext, för att identifiera potentiella risker och möjligheter ur miljösynpunkt.  Dessutom behöver IKTs roll när det gäller att stödja möjligheter till miljöförbättringar och motverka risker identifieras. Denna avhandling syftar till att ge ny kunskap om IKTs miljöpåverkan, att undersöka IKTs potential för att bidra till en hållbar utveckling, och diskutera metoder för bedömning av miljökonsekvenser av IKT samt utmaningar relaterade till den typen av bedömningar. Avhandlingen omfattar en litteraturstudie av tidigare livscykelanalyser (LCA) av IKT, en LCA-studie av traditionella och online tidningar, utveckling av ett ramverk för hållbarhetsbedömning av scenarier samt användningen av det ramverket för en miljöbedömning av framtida IKT-samhällen. Resultaten visar att andra typer av miljöpåverkan än klimatpåverkan och energi inte är tillräckligt belysta i miljöbedömningar av IKT, vilket skapar en risk för suboptimering och att miljöproblem flyttas från en typ av påverkan till en annan. Tillverknings- och användningsfasen ger upphov till störst miljöpåverkan i IKT-produkters livscykel. För nättidningar visade det sig att distribution och innehållsproduktion kan ge betydande bidrag till den totala miljöpåverkan, beroende på tidningarnas egenskaper och läsarnas beteende. Generellt har användarnas beteenden visat sig vara avgörande för resultaten vid jämförelser mellan IKT-lösningar och deras mer traditionella motsvarigheter. Ett antal nyckelområden som påverkar uppkomsten av risker och möjligheter när det gäller miljöeffekter i framtida IKT-samhällen har identifierats. De är energimix, ekonomiska förhållanden, livsstilar, teknik, samt miljöambitioner, -incitament och -lagstiftning. Potentialen för IKT att bidra till hållbar utveckling påverkas av dessa nyckelområden, och potentialen skulle troligen inte realiseras helt utan incitament eller miljölagstiftning. Båda typerna av miljöbedömningar - på produkt och samhällsnivå - är viktiga för att stödja beslutsfattande. En ny metod utvecklades för bedömning av framtidsscenarier (på samhällsnivå) – Sustainability assessment framework for scenarios (SAFS). För miljöbedömning av produkter användes livscykelanalys (LCA). Tillämpningen av båda metoderna, deras fördelar och nackdelar, och utmaningar vid användning av metoderna diskuteras. Resultat från avhandlingen kan ge underlag rörande möjliga miljöeffekter av IKT idag och i framtiden för diskussion inom IKT-sektorn och bland politiker och beslutsfattare. På så sätt kan diskussioner om hur IKT kan bidra till hållbarhet underlättas. Metodutveckling och diskussion i denna avhandling kan vara av intresse för forskare och praktiker. / <p>QC 20160613</p>
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Assessing design strategies for improved life cycle environmental performance of vehicles

Poulikidou, Sofia January 2016 (has links)
Vehicle manufactures have adopted different strategies for improving the environmental performance of their fleet including lightweight design and alternative drivetrains such as EVs. Both strategies reduce energy during use but may result in a relative increase of the impact during other stages. To address this, a lifecycle approach is needed when vehicle design strategies are developed. The thesis explores the extent that such a lifecycle approach is adopted today and assesses the potential of these strategies to reduce the lifecycle impact of vehicles. Moreover it aims to contribute to method development for lifecycle considerations during product development and material selection. Current practices were explored in an empirical study with four vehicle manufacturers. The availability of tools for identifying, monitoring and assessing design strategies was explored in a literature review. The results of the empirical study showed that environmental considerations during product development often lack a lifecycle perspective. Regarding the use of tools a limited number of such tools were utilized systematically by the studied companies despite the numerous tools available in literature. The influence of new design strategies on the lifecycle environmental performance of vehicles was assessed in three case studies; two looking into lightweight design and one at EVs. Both strategies resulted in energy and GHG emissions savings though the impact during manufacturing increases due to the advanced materials used. Assumptions relating to the operating conditions of the vehicle e.g. lifetime distance or for EVs the carbon intensity of the energy mix, influence the level of this tradeoff. Despite its low share in terms of environmental impact EOL is important in the overall performance of vehicles. The thesis contributed to method development by suggesting a systematic approach for material selection. The approach combines material and environmental analysis tools thus increases the possibilities for lifecycle improvements while minimizing risk for sub-optimizations. / <p>QC 20160920</p>

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