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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.
61

Corporate social responsibility of African and Middle East mobile operators towards climate change and the potential impact of its carbon footprint

Biewenga, Reiner 08 1900 (has links)
Research report, presented to the SBL Unisa, Midrand. / The current and future anticipated changes in the earth’s climate are a concern that has captured business’s and governments’ global attention. Climate change and its potential impacts cannot be ignored as there is ample evidence that global warming is indeed the result of anthropogenic greenhouse gas emissions. The mobile operator in Africa and the Middle East (ME) operates on continents and in parts of the world, predicted by scientists as the most vulnerable to the effects of climate change. The mobile operator in Africa and the Middle East is moreover an emitter of significant amounts of CO2 and this exacerbates the serious environmental climate change problem that humankind faces. This research paper addresses the Corporate Social Responsibility of African and Middle East (ME) mobile operators, and its Carbon Footprint. The main objectives of the research are to identify strategic risks and opportunities and the implications for the mobile operator and to determine its Greenhouse Gas emissions. The performance against targets and plans to reduce GHG emissions are also reviewed. The research is based on the questionnaire of the Carbon Disclosure Project (CDP) initiative. A shortened and modified version of the CDP was designed and emailed to two major mobile telecom operators both operating in Africa and the Middle East. It is postulated that the telecommunications industry is at an inflection point where significant changes must take place in the way energy requirements are managed. This in turn could have a positive effect on reducing its carbon footprint, benefit corporate reputation and at the same time earn “green miles” in the subscriber’s minds. The research reached the main conclusion that the mobile operators’ investigated do not yet have strategies, systems and reporting in place to be counted as “good corporate citizens” concerning their environmental responsibility. The research further concluded that a proactive strategic intent is a necessity to achieve this goal. In short: The Corporate Social Responsibility of African and Middle East mobile operators indeed has a positive effect on its Carbon Footprint.
62

Festivals and sustainability : reducing energy related greenhouse gas emissions at music festivals

Marchini, Ben January 2013 (has links)
This thesis investigates the potential to reduce greenhouse gas emissions relating to electrical power provision at UK music festivals. It has been carried out in partnership with a number of UK festival organisers and power providers. The thesis provides a literature review of sustainable event management and the associated electrical power provision, before then investigating the existing methodologies for quantifying greenhouse gas emissions at festivals. This review identified a lack of data regarding energy demand at events other than total fuel demand. While energy data does not improve the accuracy of GHG accounting, it provides more detail which can identify opportunities to reduce these emissions. Data was gathered from 73 power systems at 18 music festivals from 2009-2012. This produced typical festival power load profiles for different system types including stages, traders and site infrastructure. These load profiles were characterised using a series of indicators that can create performance benchmarks, in addition to increasing the detail of carbon auditing. Analysis of the load profiles identifies opportunities for emission reduction. These address either the supply or demand for power in order to reduce on site fuel consumption. These opportunities include changes in operating procedure to reduce demand during non-operational periods, utilising low energy equipment on stages, and using a power provision system capable of adjusting power plant supply to meet demand. The work has documented power demand at festivals, and highlighted opportunities for change that can reduce costs and emissions, as well as informing festivals on their practices.
63

Promoting low-carbon lifestyles : addressing informational needs through small-group participation

Fisher, Alice Ridgway January 2013 (has links)
Achieving the carbon emission reductions necessary to address climate change is proving challenging. Voluntary behaviour change by individuals has the potential to make a substantial contribution to decreasing carbon emissions, but generally that potential is not being realised. Group-based interventions, however, may offer an effective method for promoting significant and durable changes in pro-environmental behaviour leading to carbon reductions. This thesis evaluates Footpaths, a group-based programme designed and implemented by Transition Leicester and consisting of seven sessions. The study investigates the effectiveness of the programme, using a longitudinal mixed-methods approach to facilitate understanding of both measurable results and the processes leading to those results. The Reasonable Person Model (RPM) is used as a theoretical framework to aid understanding of the way in which group-based interventions may promote pro-environmental behaviour. Data were collected from participants just before and immediately after involvement with the Footpaths programme, as well as a year after the sessions commenced. Questionnaires were administered at all three times and semi-structured interviews were conducted after the last session. Participants also completed a carbon footprint calculator at all three times and provided data on measured energy use. Findings show that Footpaths participants reduced their carbon footprints by 15 percent over the course of the sessions, and continued to reduce their carbon footprints resulting in a 20 percent reduction over the course of a year. Pro-environmental behaviour increased, including increases in harder to change behaviours, and measured energy use decreased. Increases in pro-environmental behaviour and reductions in carbon footprint were associated with increased understanding, greater feelings of competence, and reduced confusion; all considered to be elements of a supportive informational environment. Participants highlighted the importance of having an opportunity to examine their own behaviour coupled with active engagement with information over a period of time. Neither feedback nor a desire for social contact were related to increases in pro-environmental behaviour. Pro-environmental behaviour was more closely associated with both worldview and attitude after participation in Footpaths possibly indicating a closer alignment between attitude and behaviour after participation. This research suggests that group-based interventions are effective in promoting significant and durable changes in pro-environmental behaviour and it provides interesting insight into the design of successful interventions to encourage such behaviour. Findings highlight the potential value of the RPM as an integrative framework for understanding the characteristics of interventions that successfully promote durable sustainable behaviours.
64

Defining The Geochemical Footprint For Gold Mineralisation Around Birthday Reef.Reefton Goldfield, New Zealand

Hamisi, Jonathan January 2016 (has links)
Abstract Orogenic gold deposits from the Reefton goldfield in New Zealand hosted in Ordovician metasediments of the Greenland group have produce 67 tons of gold before 1951. The Blackwater mine in Waiuta account for about 1/3 of the gold production at Reefton prior 1951. The ore system at Blackwater consist of NE trending steeply dipping gold-bearing quartz veins (Birthday reef) occurring in faulted, sheared and folded alternating sequence of sandstone-mudstone metamorphosed to low greenschist facies and hydrothermally altered proximal to distal from the quartz vein. Host rock and ore forming fluids interaction resulted in a systematic change in the mineralogy and geochemistry of the wallrock developing a distinctive footprint of the ore system. The mineral assemblage subsequent to hydrothermal alteration is formed by quartz veining, chlorite, carbonates (minor calcite-dolomite-ankerite-siderite), albite, K-Mica and composite quartz-carbonate veining, carbonates spotting, pyrite, arsenopyrite, chalcopyrite, cobaltite, galena and in a lesser extent ullmannite, gersdorffite, pentlandite, millerite and sphalerite. Mass balance calculation based on geochemical data obtained by ultra-low detection analysis with a detection limit in part per trillion of Au, As and Sb provide new insight in the geochemical footprint of the ore system at Blackwater. A clear zone of roughly 40 meters (20 meters above and below the birthday reef) is enriched in Au, As and Sb up to respectively 6806%, 605% and 891% compared to the un-mineralised protolith. Furthermore, mass changes in K2O and Na2O indicate a consistent decrease in Na and increase in K in the vicinity of the Birthday reef reflecting the replacement of albite by K-mica. This is corroborated by pattern of alkali alteration index Na/Al for albite and 3K/Al for K-Mica showing similar trend. Carbonation and de/-hydration index also exhibits peaks in samples adjacent to the Birthday reef, though carbonation index is also influenced by carbonates content in the protolith or late carbonation that may not related to gold mineralisation. Using the indicators above-mentioned it is possible to define the mineralogical and geochemical “footprint” for the ore system in the host rock allowing to use this footprint as a tool for mineral exploration for orogenic gold deposits similar to Blackwater. Given that the geochemical footprint of orogenic gold deposit such as Blackwater is significantly wider than the economically viable part of the deposit defining the footprint of the ore system offers the potential for vectoring from sub-economic mineralisation towards higher-grade ore that is economically viable.
65

Microalgae to energy : biomass recovery and pre-treatments optimisation for biogas production integrated with wastewater nutrients removal

Ometto, Francesco January 2014 (has links)
The increasing concern about water quality and energy demand promotes the development of innovative and low-cost processes to improve the nutrient uptake and energy efficiency of existing wastewater treatments (WWT). In this context, the inclusion of a microalgae system (MAS) in the flowsheet of a WWT plant represents a sustainable alternative to conventional technologies, as it combines a low-cost nutrient uptake system with the production of biomass suitable for biofuel production. However, at present, the energy required to cultivate and process the algae cells is often too high to justify their use. The adoption of a low energy harvesting system and an efficient energy conversion process are the sine qua non requirements to guarantee the sustainability of the process. In this thesis, current and innovative harvesting technologies for large scale applications have been reviewed to identify the optimal working conditions of each system and their link to the main characteristics of the algae suspension. In particular, the performance of the Ballasted Dissolved Air Flotation (BDAF) system was investigated using different algae and compared to the conventional Dissolved Air Flotation (DAF). BDAF was demonstrably a very viable harvesting method where the use of floating microspheres as ballasting agents allowed significant coagulant savings, reduced the level of energy dissipation within the flotation chamber, and lowered the overall carbon emissions and the process costs. Cont/d.
66

Carbon and energy payback of variable renewable generation

Thomson, Rachel Camilla January 2014 (has links)
The continued drive to reduce Greenhouse Gas (GHG) emissions in order to mitigate climate change has led to an increase in demand for low-carbon energy sources, and the development of new technologies to harness the available energy in the wind, waves and tides. Many controversies surround these technologies, however, particularly with regards to their economic cost, environmental impacts and the implications of the variability of their output for security of the electricity supply. In order to make informed policy decisions on future developments of the electricity system, it is necessary to address these controversies and confirm the environmental, economic and social sustainability of these new renewable generators. This thesis specifically examines two key issues: whether new variable-output renewable energy generators actually deliver a net reduction in greenhouse gas emissions over their lifetimes, and whether they produce a viable energy return on energy investment. Although renewable energy sources are themselves ‘carbon free’, GHG emissions (and energy consumption) occur during the construction, maintenance and decommissioning of the generator infrastructure required to convert this energy into electricity. Furthermore, the variability of the output power from such generators has implications for the operation of the grid - there may be a requirement for additional reserve capacity and the increased part-loading of conventional plant is likely to reduce its operating efficiency. Carbon and energy paybacks are measures of the time required for a new renewable installation to offset these life cycle impacts. The work presented in this thesis examines both the life cycle impacts and the GHG emissions displacement of variable renewable generation, using Great Britain as a case study, in order to provide a basis for significantly more robust and reliable estimates of carbon and energy paybacks. The extensive literature survey concentrates on two key areas: current calculation methodologies and estimates for life cycle carbon and energy consumption of power generators; and the marginal emissions displacement of variable renewable generation. A detailed life cycle assessment of the Pelamis wave energy converter is presented, which sets the embodied carbon and energy in the context of the wider environmental impacts and includes an examination of the effect of different assumptions on the analysis results. In order to investigate the true emissions displacement of renewable generation, a historical analysis of real data from the National Grid was carried out, identifying the marginal displacement factor of wind power and taking into account the effect of the efficiency penalties of conventional plant. The findings of the analyses presented in this thesis are combined with information from the literature to examine the actual carbon and energy payback of existing renewable generation infrastructure on the British grid, and to provide detailed recommendations for future carbon and energy payback calculations.
67

Klimatanalys av avloppsreningsverk : Analyser av två av Laholmsbuktens VA:s avloppsreningsverk med förslag på förbättringsåtgärder

Adriansson, Emma, Turesson, Linnéa January 2016 (has links)
The intensified greenhouse effect is the biggest cause for a negative climate change. Global warming is a result of enhanced greenhouse effect and poses a potential threat for humans and its surrounding environment that can result in disastrous consequences. The rise in temperature is driven by increased human activity whereas the leading cause for emissions of greenhouse gases is the combustion of fossil fuels. The prominent source of emissions is from the following sectors: transport, industrial and energy. The task of reducing the emissions of greenhouse gases is both globally and internationally prioritized. Progress has been made although every potential source for emissions has to be investigated in order to reduce the total climate impact. Based on scientific research, wastewater treatment plants are also a contributing factor to the greenhouse effect by emissions of gases. This bachelor’s thesis is investigating two wastewater treatment plants and identifying which processes contribute to the climate impact. The climate impact is calculated with an Excel-based analyzing tool and the results show the Carbon Footprints for the treatment plants. The purpose of this paper is to present result acquired from the treatment plants and identify the processes that have the biggest impact on our climate. Afterwards, solutions derived from the analysis of results will be suggested to improve and bring additional help to the treatment plants with their climate work. In conclusion, it is determined that the treatment plants both have net emissions of greenhouse gases. The biggest contributor is the wastewater treatment and the use of biogas. Results from analysis show that some of the assumptions on emissions made in the tool make the initial results doubtful. Therefore, further research is needed on this subject in order to produce more reliable facts.
68

Integrating life cycle analysis and the ecological footprint calculator to foster sustainable behaviors

Anderle, Kathryn 12 1900 (has links)
Many tools have been developed to assess global, national or regional sustainable development policies. However, as governments develop sustainable policies, individuals must also feel empowered to affect their personal impact on the planet. This thesis integrates three sustainability concepts that lend themselves to individual sustainability: The natural step, life cycle assessment, and the ecological footprint. TNS serves to provide the meaning and substance toward sustainable development. LCA helps provide the framework for assessing sustainability. The EF calculator determines the driving components and measures the qualitative decisions made through TNS and LCA. From the analysis of the household footprint calculator a simplified footprint calculator was developed to assist individuals and communities in setting benchmarks and goals as they move away from over-consumption and towards a sustainable lifestyle.
69

Identifying priority areas for European resource policies: a MRIO-based material footprint assessment

Giljum, Stefan, Wieland, Hanspeter, Lutter, Franz Stephan, Bruckner, Martin, Wood, Richard, Tukker, Arnold, Stadler, Konstantin 06 June 2016 (has links) (PDF)
In the context of the transformation toward a "green economy," issues related to natural resource use have rapidly increased in importance in European and international policy debates. The large number of studies applying economy-wide material flow analysis so far mostly produced aggregated national indicators, making the results difficult to connect to policies, which are often designed for single sectors or consumption areas. This paper provides a detailed assessment of the composition of EU's material footprint in its global context, aiming at identifying the main product groups contributing to overall material consumption and specifying the geographical sources for the raw materials required to satisfy EU's final demand. Based on multi-regional input¿output (MRIO) modeling, we apply production layer decomposition to assess supply chains and their structural changes from 1995 to 2011. The global MRIO database used in this study is EXIOBASE 3, which disaggregates 200 products and 163 industries, of which 33 represent material extraction sectors. By that means, we increase the level of detail to a degree where policies can more easily connect to. We find that the generally growing material footprint of the EU was characterized by a dramatic shift regarding the origin of raw materials, with the share of materials extracted within the EU territory falling from 68 % in 1995 to 35 % in 2011. In 2011, raw materials extracted in China to produce exports to the EU already contributed an equal share to EU's material footprint as material extraction within the EU itself. Import dependency is most critical for the material group of metal ores, with only 13 % of all metals required as inputs to EU final demand stemming from within the EU. Regarding product composition, construction was confirmed as the most important sector contributing to the material footprint, followed by the group of manufacturing products based on biomass. Materials embodied in service sector activities together contributed a quarter to the total material footprint in 2011, making services an important, but currently disregarded area for European resource policies. We also find that supply chain structures became more complex over time, with a growing part located outside the EU territory. (authors' abstract)
70

Material Footprint Assessment in a Global Input-Output Framework

Giljum, Stefan, Bruckner, Martin, Martinez, Aldo 30 December 2014 (has links) (PDF)
Material flow-based indicators play an important role in indicator sets related to green and resource-efficient growth. This paper examines the global flows of materials and the amounts of materials directly and indirectly necessary to satisfy domestic final demand in different countries world-wide. We calculate the indicator Raw Material Consumption (RMC), also referred to as Material Footprint (MF), by applying a global, multi-regional input-output (MRIO) model based on the GTAP database and extended by material extraction data. We examine world-wide patterns of material extraction and materials embodied in trade and consumption, investigating changes between 1997 and 2007. We find that flows of materials related to international trade have increased by almost 60% between 1997 and 2007. We show that the differences in Material Footprints per capita are huge, ranging from up to 100 tonnes in the rich, oil-exporting countries to values as low as 1.5 to 2 tonnes in some developing countries. We also quantify the differences between the indicators Domestic Material Consumption (DMC) and RMC, illustrating that net material exporters generally have a DMC larger than RMC, while the reverse is observed for net importers. Finally, we confirm the fact that most countries with stable or declining DMCs actually show increasing RMCs, indicating the occurrence of leakage effects, which are not fully captured by DMC. This challenges the world-wide use of DMC as a headline indicator for national material consumption and calls for the consideration of upstream material requirements of international trade flows.

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