61 |
CO2 Sequestration by Bio-Accelerated Silicate Weathering / CO2-infångning genom bio-accelererad silikatvittringUebel, Tora, Odelius, Elisabeth January 2023 (has links)
Human-caused emissions of CO2 and other greenhouse gases are an established reason for the climate changes that affect planet Earth. Negative emission technologies (NETs), for example, bio-accelerated silicate weathering bioreactors, seek to capture and store carbon from the atmosphere. Bio-acceleratedsilicate weathering utilizes microorganisms to increase natural silicate weathering processes.This project aimed to evaluate the potential bio-accelerated weathering of two silicate rock types, Basalt Lavagestine, and La Palma lapilli, using a mixture of microorganisms, Bacillus Subtilis, Cupriavidus Metallidurans, Aureobasidium Pullulans, and Suillus Variegatus. Straw was used as an organic carbon and nutrient source for the organisms. There were six types of reactors, biotic, abiotic,and mineral controls for each of the two minerals, with triplicates. The reactors were watered five times a week with 50 mL of autoclaved distilled water, after each week the leachate from each reactor wascollected. Geochemical analyses of all leachates were performed, these were pH, conductivity, alkalinity, and carbon analyses. After the experiment, the mineral grains and straw were examined in a scanning electron microscope (SEM) to observe the growth of organisms and the differences between reactor types.The biotic reactors for both minerals showed signs of enhanced weathering compared to their controls. The geochemical analyses showed that the alkalinity was doubled between the abiotic and biotic reactors for the basalt, and increased by roughly a third for the lapilli. The DIC was tripled for thebiotic basalt and doubled for the biotic lapilli. This indicated increased weathering rates and more sequestered carbon for the biotic reactors. SEM showed growth of fungi and bacteria in all biotic reactors. The extensive growth of fungi and biofilm formation was prominent in the basalt Lavagestineand a possible reason for the increased weathering compared to lapilli. The contrast in the surface structure of the minerals could be a second reason for the result. The two bacteria were colonizing one mineral each, which indicates differences in chemical composition. The C.Metallidurans were observed on the basalt grains and B.Subtilus on the lapilli. This report concludes that bio-enhanced weathering isa promising aspirant for NETs and that the selection of minerals is an important factor.
|
62 |
Toward Sustainable Development: Quantifying Environmental Impact via Embodied Energy and CO2 Emissions for Geotechnical ConstructionShillaber, Craig Michael 16 March 2016 (has links)
With rising awareness that future generations may not have access to the resources and quality of life that exist today, sustainable development has become a priority within civil engineering. One important component of sustainable development is environmental stewardship, which concerns both the resources taken from the environment, and the wastes and byproducts emitted to the environment. To facilitate more sustainable development, environmental accounting is necessary within civil and geotechnical engineering design and construction. Historically, geotechnical practice has focused on maximizing design performance while minimizing monetary costs, and well established methods exist for quantifying these factors. Quantitative consideration of environmental consequences has seldom played a large role in geotechnical design and construction, and clear guidelines and a methodology for such an assessment are not available within the geotechnical profession. Therefore, this research has focused on establishing a method for quantitative streamlined environmental Life Cycle Analysis of energy and carbon dioxide (CO2) emissions for geotechnical ground improvement works, known as the Streamlined Energy and Emissions Assessment Model (SEEAM). The boundaries for the SEEAM extend from raw material extraction through the completion of construction, including the energy and CO2 emissions associated with construction materials, construction site operations, and the transportation of construction materials and wastes. The methodology relies on energy and CO2 emissions coefficients, which represent typical industry average values and not necessarily the specific processes contributing to a project. Therefore, there is uncertainty in SEEAM analyses, which is addressed via a Monte Carlo simulation framework that assumes the energy and CO2 emissions coefficients each follow a lognormal distribution. Data sets of total energy and CO2 emissions generated by the Monte Carlo simulation framework with the SEEAM may be used to statistically compare the energy and CO2 emissions of different geotechnical design alternatives. Such comparisons can help facilitate designing for minimum environmental consequences, thus advancing sustainable development within geotechnical engineering. For clarity, the development and application of the SEEAM is illustrated using two different geotechnical case history projects, including rehabilitation of levee LPV 111 in New Orleans, LA, and the construction of foundations for a replacement dormitory on the Virginia Tech campus. / Ph. D.
|
63 |
Unlocking power: impact of physical and mechanical properties of biomass wood pellets on energy release and carbon emissions in power sectorScott, Charlene, Desamsetty, Tejaswi M., Rahmanian, Nejat 02 September 2024 (has links)
Yes / This study investigates the physical and mechanical properties of 12 biomass wood pellet samples utilised in a power generation, focusing on their implications for energy release and carbon emissions during combustion. Through comprehensive analysis involving bulk density measurements, compression tests, moisture analysis, calorimetry and controlled burning experiments, significant correlations among key properties are identified. Pellets with densities above 1100 kg/m3 demonstrate superior mechanical durability and strength, achieving maximum strengths of 0.6 to 0.8 kN with durability exceeding 99.4%. Optimal moisture content, typically between 6 and 7% is crucial for maximising density, bulk density, mechanical durability and fracture resistance, ensuring robust pellet structure and performance. The research underscores the impact of pellet dimensions, highlighting those longer lengths, > 12 mm enhance durability, while larger diameters > 8 mm exhibit reduced durability. Elemental analysis focusing on calcium, silicon and potassium plays a critical role in predicting and managing combustion system fouling, potentially reducing operational costs. Moreover, the study emphasises the significant influence of oxygen levels during combustion on CO2 emissions, achieving optimal results with moisture content in the 7–8% range for maximum higher heating value (HHV). The moisture content in the 14–15% range represents the lowest CO2 emission. The findings underscore the intricacy of the system and the interplay of parameters with one another. In accordance with the priority of each application, the selection of parameters warrants careful consideration. / This work was supported by the UK Carbon Capture and Storage Research Community (UKCCSRC) and the Engineering and Physical Sciences Research Council (EPSRC) through the UKCCSRC Flexible Funding Call 2022.
|
64 |
Enabling sustainable energy futures: factors influencing green supply chain collaborationIrani, Zahir, Kamal, M.M., Sharif, Amir M., Love, P.E.D. 2017 May 1916 (has links)
Yes / This article explores the relationship between sustainability strategies and future energy needs, supply chains need to reduce their CO2 emissions through developing their green credentials and improving performance. Knowledge management (KM) is an enabler to support collaboration efforts. The SCM and KM areas have largely focused on improving organisational performance. While the latter has yielded successful outcomes in different sectors, there is still a scarcity of research on identifying influential factors highlighting those aspects which may enable green supply chain collaboration (GrSCC), thus leading to sustainable energy futures and carbon-efficient production. This paper examines the role of KM in facilitating GrSCC. Through the identification of key factors extrapolated from the literature, a model for implementing GrSCC using a futures-based perspective is proposed. This paper inductively demonstrates the relationship between identified GrSCC factors through fuzzy cognitive mapping technique. Findings support a futures-based perspective that enhances understanding and refines forward-looking strategies for GrSCC.
|
65 |
Introducing a new measure of energy transition: Green quality of energy mix and its impact on CO2 emissionsLau, C.K., Gozgor, Giray, Mahalik, M.K., Patel, G., Li, Jing 30 April 2023 (has links)
Yes / This paper introduces a novel measure of the energy transition, i.e., the green quality of energy mix (GREENQ) across the Organisation for Economic Co-operation and Development (OECD) countries. Then, the paper examines the impact of the GREENQ on CO2 emissions in the panel dataset of 36 OECD countries from 1970 to 2021. The explanatory variables include per capita income, institutional quality and technology. Long-run panel data estimations indicate that per capita income, institutional quality and technology increase CO2 emissions. The novel evidence is that the GREENQ is negatively related to the level of CO2 emissions. These findings are robust to employ different panel data estimation techniques. Potential policy implications are also discussed. / The project was funded by the “Foreign Cultural and Educational Experts Project of the Ministry of Science and Technology of China” (Project Number: DL2022180001L).
|
66 |
The impact of geopolitical risk on CO2 emissions inequality: Evidence from 38 developed and developing economiesChen, L., Gozgor, Giray, Lau, C.K.M., Mahalik, M.K., Rather, K.N., Soliman, A.M. 09 February 2024 (has links)
Yes / This paper analyses the impact of geopolitical risk on carbon dioxide (CO2) emissions inequality in the panel
dataset of 38 developed and developing economies from 1990 to 2019. At this juncture, the empirical models
control for the effects of globalisation, capital-labour ratio, and per capita income on CO2 emissions inequality.
The panel cointegration tests show a significant long-run relationship among the related variables in the
empirical models. The panel data regression estimations indicate that geopolitical risk, capital-labour ratio, and
per capita income increase CO2 emissions inequality. However, globalisation negatively affects CO2 emissions
inequality in the panel dataset of 38 developed and developing countries. The pairwise panel heterogeneous
causality test results align with these benchmark results and indicate no reverse causality issue. Potential policy
implications are also discussed. / The authors acknowledge the grant from the Major Project of Philosophy and Social Science Research in Colleges (Grant Number: 2023SJZD027).
|
67 |
Cross-efficiency analysis of energy sector using stochastic DEA: Considering pollutant emissionsHadi-Vencheh, A., Kohdadadipour, M., Tan, Yong, Arman, H., Roubaud, D. 16 July 2024 (has links)
Yes / Undesirable outputs can be challenging to avoid in the production of goods and services, often overlooked. Pollution is generally regarded as a negative externality and is taken into account during the production process. The novelty of this study lies in introducing CO2 as an economic “bad” in the energy sector's efficiency measure through a stochastic data envelopment analysis (DEA) cross-efficiency model. Unlike pollution and economic goods, where increased production leads to more pollution, CO2 is weakly disposable, meaning that higher CO2 values lead to a decrease in the number of good outputs produced. The study proposes a new stochastic model based on an extension of the cross-efficiency model and applies it to measure the energy efficiency of 32 thermal power plants in Angola in the presence of undesirable outputs. This will help promote better environmental management. The study's findings offer vital policy insights for the energy sector. The introduction of new stochastic models enables more accurate efficiency measurement under uncertain conditions, aiding policymakers in resource allocation decisions. Additionally, the adoption of stochastic cross-efficiency methods enhances performance assessments, facilitating targeted interventions for underperforming units. These findings contribute to evidence-based policymaking, promoting sustainability and competitiveness within the energy sector.
|
68 |
The impact of innovative ICT technologies on the power consumption and CO2 emission of HTTP serversSoler Domínguez, Sebastian January 2022 (has links)
The ICT technologies and their adoption from the population are growing fast, and the energy that this industry requires has followed the same trend, even considering all the improvements in efficiency during the last decades. This is because the increment in data centers and information outpaces all the efficiencies that have been adopted over the years. The HTTP servers have been optimizing data usage performance over the years, however, data centers still consume more and more energy due to the high demand they have. The objective of this study is to develop a tool that compares cache and non-cache servers' energy, hence CO2 emissions performances, using a simple and an advanced model. The simple model is based on a compilation of extensive data analysis including more detailed information and inputs, and the advanced model considers an energy consumption comparison between cache and non-cache technology. A database of CO2 emissions per MWh of 49 countries is created that forecasts this rate until 2030. The results show that cache servers are between 20% and 5% more efficient than non-cache in terms of energy consumption for files under 5MB. However, the efficiency level varies depending on the file size that is transferred. Therefore, improved ICT technology has the potential to reduce thousands of tons of CO2 per year if more websites adopt it. For example, an average news website with 300k visits per day could reduce around 150 tonCO2/year. / IKT-teknikerna och deras antagande från befolkningen växer snabbt, och den energi som denna industri kräver har följt samma trend, även med tanke på alla effektivitetsförbättringar under de senaste decennierna. Detta beror på att ökningen av datacenter och information överträffar alla effektivitetsvinster som har antagits under åren. HTTP-servrarna har optimerat dataanvändningsprestanda under åren, men datacenter förbrukar fortfarande mer och mer energi på grund av den höga efterfrågan de har. Syftet med denna studie är att utveckla ett verktyg som jämför cache- och icke-cache-servrars energi, därav CO2-utsläppsprestanda, med hjälp av en enkel och en avancerad modell. Den enkla modellen är baserad på en sammanställning av omfattande dataanalyser inklusive mer detaljerad information och indata, och den avancerade modellen tar hänsyn till en energiförbrukningsjämförelse mellan cache- och icke-cache-teknik. En databas med CO2-utsläpp per MWh för 49 länder skapas som prognostiserar denna takt fram till 2030. Resultaten visar att cacheservrar är mellan 20% och 5% effektivare än icke-cache vad gäller energiförbrukning för filer under 5MB. Effektivitetsnivån varierar dock beroende på filstorleken som överförs. Därför har förbättrad IKT-teknik potential att minska tusentals ton CO2 per år om fler webbplatser använder den. Till exempel kan en genomsnittlig nyhetswebbplats med 300 000 besök per dag minska cirka 150 ton CO2/år.
|
69 |
Sustainability Strategies in IKEA with the focus on Production and SuppliersYang, Lilia, Shao, Nanxiang January 2019 (has links)
“Waste of resources is a mortal sin at IKEA.” – Ingvar Kamprad IKEA, as one of the biggest furniture companies in the world (Alänge, 2015), makes it interesting to have a look into their practices to gain a deeper insight by looking at how they work on a more sustainable and environmental friendlier world. Since Ingvar Kamprad, the founder of this company, mentioned sustainability from the earliest years, this work will provide an insight on how the sustainability annual reports of IKEA present their sustainability strategies to the reader every year. The researchers use the secondary analysis method to provide the theoretical framework and apply a case study to conduct the empirical data of the company IKEA. Since (Harte et al., 1991) pointed out that annual reports are an important source of environmental information. The database is in form of annual reports from the year 2010 till 2018 that were provided by the company IKEA itself. Through the pattern matching method the numbers over the years are compared and discussed due to their development. Furthermore, the areas “production” and “supplier” are selected from the supply chain management and also included in the analyzes section, since both, the development of other organizational relationships in the supply chain and the environmental corporation can become an integral part of the company (Seuring & Müller, 2008). Through diagrams in the empirical chapter this work will provide a comparison between the different factors in the mentioned areas of the supply chain management and discuss the actual development and partly improvements of the factor’s “energy”, “waste”, “production” etc. and the promises and goals from the IKEA’s side.
|
70 |
La mobilité pendulaire interurbaine en France face aux enjeux du changement climatique : caractérisation socioéconomique, analyse spatiale et potentiels de report modal / The intercity commuter mobility in France facing the challenges of climate change : socioeconomic characterization, spatial analysis and potential modal shiftConti, Benoit 07 December 2016 (has links)
L’étude de la mobilité domicile-travail fait l’objet de nombreuses recherches visant à décrire et analyser les caractéristiques des actifs et de leurs déplacements. En France, ces études se concentrent principalement sur les individus vivant dans les espaces fonctionnels construits autour des agglomérations, les aires urbaines. Cette thèse vise à fournir une lecture complémentaire de ces travaux en étudiant les personnes qui se déplacent entre aires urbaines : les actifs interurbains.À partir d’une approche quantitative à l’échelle de la France continentale, menée principalement grâce aux bases de données du recensement de la population, une qualification des actifs interurbains est proposée. Nos résultats montrent une diversité des profils d’actifs en matière de caractéristiques sociodémographiques, ainsi qu’une pluralité de types de liaisons réalisées entre les différents espaces des aires urbaines. Nos travaux mettent également en évidence l’importance de l’usage de la voiture, principal mode de transport utilisé par les actifs interurbains. Aussi, malgré leur poids relativement faible dans la population des aires urbaines grandes et moyennes en France, ces actifs qui se déplacent sur de grandes distances en voiture sont alors responsables d’un volume important d’émissions de CO2.Ce dernier résultat a conduit à quantifier des potentiels de report modal des déplacements des interurbains de la voiture vers le réseau ferroviaire afin de réduire le volume de ces émissions. Nos résultats démontrent l’existence de leviers permettant de réduire théoriquement ces émissions liées à l’usage de l’automobile. Le facteur spatial, à différentes échelles, joue un rôle important dans les différences entre potentiels. Enfin, nous avons également montré que ces mesures ont des conséquences sociales distinctes, en matière de coût, en fonction des professions et catégories socioprofessionnelles / Commuter mobility is the subject of numerous studies meaning to describe and analyze the characteristics of commuters and their movements. In France, these studies focus primarily on people living in the functional area built around cities, called French urban areas. This thesis aims to provide supplementary insight on this topic by studying people moving between those French urban areas: intercity commuters.Analysing the French mainland population thought a quantitative approach conducted using census databases, measurement and qualification of long-distance commuters are proposed. Our results show a diversity of commuters in terms of demographic profile and spatial connections. The important use of the car as the primary mode of transport is emphasized. Despite their relatively low weight in the population of large and medium-sized urban areas in France, those commuters, who travel over long distances by car, are responsible for significant volumes of CO2 emissions.This result led to quantify the potential modal shift from car to rail. Our results demonstrate the existence of levers to theoretically reduce car use and thus the importance of its emissions. The influence of the spatial factor, at different scales, is attested. Furthermore such policies would have different consequences in terms of cost for the various professions and socio-professional categories
|
Page generated in 0.0766 seconds