Search results for: energy conservation and transition

Authors: Robert Lindner

Abstract:

In recent years a multitude of international efforts, including the United Nations’ aspirational 2030 Agenda for Sustainable Development, provided a new momentum to facilitate energy access and rural electrification projects to combat energy poverty in developing states in Asia. Rural electrification projects promise to facilitate other sustainable development aims, such as the empowerment of local communities through the creation of economic opportunities or increased disaster resilience. This study applies a multi-governance research framework to study the cases of the ongoing energy system transition in Myanmar and Cambodia. It explores what impact the international aid community, especially multilateral development banks and international development agencies, has on the governance of the transitions and how diverging aid donor interest shape policy making and project planning. The study is based on policy analysis and expert interviews, as well as extensive field research. It critically examines the current development trajectories and the strategies of the stakeholders involved. It concludes that institutional and technological competition between donors, as well as a lack of transparency and inclusion in the project planning and implementation phases, contributes to insufficient coordination in national energy policy making and project implementation at the local level. The study further discusses possible alternative approaches that might help to promote the spread of sustainable energy technologies.

Keywords: energy governance, developing countries, multi-level governance, energy transitions

Procedia PDF Downloads 112

Authors: Davyd Urbanas, Pranas Baltrenas

Abstract:

It is well-known that, despite the constant increase of alternative energy sources usage, today combustible fuels are still widely used in power engineering. As a result of fuel combustion, significant amounts of nitrogen oxides (NOx) and carbon monoxide (CO is a product of incomplete combustion) are supplied to the atmosphere. Also, these pollutants are formed in industry (chemical production, refining, and metal production). In this work, the investigation of nitrogen oxides CO-selective catalytic reduction using new grain load-type catalysts was carried out. The catalysts containing the substrate and a thin active coating made of transition metal (Mn, Cu, and Nb) oxides were prepared with the use of electroless chemical deposition method. Chemical composition, chemical state, and morphology of the formed active coating were investigated using ICP-OES, EDX, SEM, and XPS techniques. The obtained results revealed that the prepared catalysts (Cu-Mn-oxide and Cu-Mn-Nb-oxide) have rough and developed surface and can be successfully used for the flue gas catalytic purification. The significant advantage of prepared catalysts is their suitability from technological application point of view, which differs this work from others dedicated to gas purification by SCR.

Keywords: flue gas, nitrogen oxides, selective catalytic reduction, transition metal oxides

Procedia PDF Downloads 158

Authors: G. Çelik Gül, F. Kurtuluş

Abstract:

Colemanite is the most common borate mineral, and the main source of the boron required by plants, human, and earth. Transition metals exhibit optical and physical properties such as; non-linear optical character, structural diversity, thermal stability, long cycle life and luminescent radiation. The doping of colemanite with a transition metal, bring it very interesting and attractive properties which make them applicable in industry. Iron doped calcium borate was synthesized by conventional solid state method at 1200 °C for 12 h with a systematic pathway. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy/energy dispersive analyze (SEM/EDS) were used to characterize structural and morphological properties. Also, thermal properties were recorded by thermogravimetric-differential thermal analysis (TG/DTA). 

Keywords: colemanite, conventional synthesis, powder x-ray diffraction, borates

Procedia PDF Downloads 332

Authors: A. P. Srivastava, D. Srivastava, D. J. Browne

Abstract:

Relaxation dynamics of Zr44Cu40Al8Ag8 bulk metallic glass (BMG) has been probed using dynamic mechanical analyzer. The BMG sample was casted in the form of a plate of dimension 55 mm x 40 mm x 3 mm using tilt casting technique. X-ray diffraction and transmission electron microscope have been used for the microstructural characterization of as-cast BMG. For the mechanical spectroscopy study, samples in the form of a bar of size 55 mm X 2 mm X 3 mm were machined from the BMG plate. The mechanical spectroscopy was performed on dynamic mechanical analyzer (DMA) by 50 mm 3-point bending method in a nitrogen atmosphere. It was observed that two glass transition process were competing in supercooled liquid region around temperature 390°C and 430°C. The supercooled liquid state was completely characterized using DMA and differential scanning calorimeter (DSC). In addition to the main α-relaxation process, presence of β relaxation process around temperature 360°C; below the glass transition temperature was also observed. The β relaxation process could be described by Arrhenius law with the activation energy of 160 kJ/mole. The volume of the flow unit associated with this relaxation process has been estimated. The results from DMA study has been used to characterize the shear transformation zone in terms of activation volume and size. High fragility parameter value of 34 and higher activation volume indicates that this alloy could show good plasticity in supercooled liquid region. The possible mechanism for the relaxation processes has been discussed.

Keywords: DMA, glass transition, metallic glass, thermoplastic forming

Procedia PDF Downloads 295

Authors: Yakup Sahin, Naim Suleyman Ting, Ismail Aksoy

Abstract:

A 1 kW power factor correction boost converter with an active snubber cell is presented in this paper. In the converter, the main switch turns on under zero voltage transition (ZVT) and turns off under zero current transition (ZCT) without any additional voltage or current stress. The auxiliary switch turns on and off under zero current switching (ZCS). Besides, the main diode turns on under ZVS and turns off under ZCS. The output current and voltage are controlled by the PFC converter in wide line and load range. The simulation results of converter are obtained for 1 kW and 100 kHz. One of the most important feature of the given converter is that it has direct power transfer as well as excellent soft switching techniques. Also, the converter has 0.99 power factor with the sinusoidal input current shape.

Keywords: power factor correction, direct power transfer, zero-voltage transition, zero-current transition, soft switching

Procedia PDF Downloads 962

Authors: Şule Yanık, Emel Ertürk-Mustul, Zerrin Turan, Hasan Gürgür

Abstract:

It is known that there are policies that will support the early special education (ESE) for children requiring special care including the children with hearing loss (CHL) in many countries that give importance to early childhood (0-6 years) education, accordingly ESE services have been gradually increasing and these services provide positive contributions to the child and family. These services begin with medical diagnostics, provision of the use of assistive technologies for hearing and the orientation of children towards early education program (EEP) for the CHL. In 0-3 years of age EEP, education and support services are provided to the children and their families. In 3-6 years of age, children are supported in a pre-school education program (PSE) in which their peers and teachers are present. Therefore, the children with hearing loss and their families are going through a series of medical, educational and social transition process after diagnosed with hearing loss. Depending on their age and development, CHL also go through a transition period from hospital to home, from home to EEP and from EEP to PSE. It is seen that there is no legal regulation regarding the transition process in Turkey and hence different processes have been carried out in the transition process from EEP to PSE. The aim of this study is to reveal the problems confronted by the CHL during the transition period from EEP to PSE and the solution proposals for these problems. In this study, a document review was made by reviewing the national and international studies about transition processes of the CHL in Turkey from EEP to PSE. Accordingly, in the study carried out in two stages, firstly, a review of the body of literature was performed by creating key words related to the subject. Secondly, the problems confronted by the CHL in Turkey during the transition period from EEP to PSE and the solution proposals for these problems were demonstrated by analyzing the obtained data. According to the body of literature, it is seen that there are no laws concerning the transition processes of the children who require special care including the CHL in Turkey from EEP (sending) to PSE (receiving), and correspondingly numerous problems have been experienced during the transition period. It seems that the EEP adopts family-centered approaches for strengthening the families of the CHL. However, PSE program aims to prepare the children to school life by focusing on their social and academical development rather with the adoption of children-centered approaches. Therefore, while the families feel an inseparable part of the team in EEP, they indicated that they felt like a stranger in the school team after their children have started to PSE. Therefore, families find the transition processes worrisome and state that they are not satisfied with the process. We discovered that in the process of transition from EEP to PSE, families are not informed, there is a limited number of PSE options available, children cannot adapt to the new educational environment and cannot benefit from the existing PSE.

Keywords: early education program, early special education, children with hearing loss, transition

Procedia PDF Downloads 144

Authors: Mohammad Saeed Bahramy

Abstract:

Transition metal dichalcogenides have experienced a resurgence of interest in the past few years owing to their rich properties, ranging from metals and superconductors to strongly spin-orbit-coupled semiconductors and charge-density-wave systems. In all these cases, the transition metal d-electrons mainly determine the ground state properties. This presentation focuses on the chalcogen-derived states. Combining density-functional theory calculations with spin- and angle-resolved photoemission, it is shown that these states generically host a coexistence of type I and type II three-dimensional bulk Dirac fermions as well as ladders of topological surface states and surface resonances. It will be discussed how these naturally arise within a single p-orbital manifold as a general consequence of a trigonal crystal field, and as such can be expected across many compounds. Our finding opens a new route to design topological materials with advanced functionalities.

Keywords: topology, electronic structure, Dirac semimetals, transition metal dichalcogenides

Procedia PDF Downloads 165

Authors: Aldona Kluczek

Abstract:

Energy efficient process have become a pressing research field in manufacturing. The arguments for having an effective industrial energy efficiency processes are interacted with factors: economic and environmental impact, and energy security. Improvements in energy efficiency are most often achieved by implementation of more efficient technology or manufacturing process. Current processes of electricity production represents the biggest consumption of energy and the greatest amount of emissions to the environment. The goal of this study is to improve the potential energy-savings and reduce greenhouse emissions related to improvement scenarios for the treatment of hardwood lumber produced by an industrial plant operating in the U.S. through the application of green balancing procedure, in order to find the preferable efficient technology. The green procedure for energy is based on analysis of energy efficiency data. Three alternative scenarios of the cogeneration systems plant (CHP) construction are considered: generation of fresh steam, the purchase of a new boiler with the operating pressure 300 pounds per square inch gauge (PSIG), an installation of a new boiler with a 600 PSIG pressure. In this paper, the application of a bottom-down modelling for energy flow to devise a streamlined Energy and Emission Flow Analyze method for the technology of producing electricity is illustrated. It will identify efficiency or technology of a given process to be reached, through the effective use of energy, or energy management. Results have shown that the third scenario seem to be the efficient alternative scenario considered from the environmental and economic concerns for treating hardwood lumber. The energy conservation evaluation options could save an estimated 6,215.78 MMBtu/yr in each year, which represents 9.5% of the total annual energy usage. The total annual potential cost savings from all recommendations is $143,523/yr, which represents 30.1% of the total annual energy costs. Estimation have presented that energy cost savings are possible up to 43% (US$ 143,337.85), representing 18.6% of the total annual energy costs.

Keywords: alternative scenario improvements, cogeneration system, energy and emission flow analyze, energy balancing, green procedure, hardwood lumber manufacturing process

Procedia PDF Downloads 208

Authors: Sergey Nikitenko, Vladimir Klishin, Yury Malakhov, Elena Goosen

Abstract:

Transition to renewable energy sources (solar, wind, bioenergy, etc.) and launching of alternative energy generation has weakened the role of coal as a source of energy. The Paris Agreement and assumption of obligations by many nations to orderly reduce CO₂ emissions by means of technological modernization and climate change adaptation has abridged coal demand yet more. This paper aims to assess current resilience of the coal industry to stress and to define prospects for coal production optimization using high technologies pursuant to global challenges and requirements of energy transition. Our research is based on the resilience concept adapted to the coal industry. It is proposed to divide the coal sector into segments depending on the prevailing value chains (VC). Four representative models of VC are identified in the coal sector. The most promising lines of upgrading VC in the coal industry include: •Elongation of VC owing to introduction of clean technologies of coal conversion and utilization; •Creation of parallel VC by means of waste management; •Branching of VC (conversion of a company’s VC into a production network). The upgrade effectiveness is governed in many ways by applicability of advanced coal processing technologies, usability of waste, expandability of production, entrance to non-rival markets and localization of new segments of VC in receiving regions. It is also important that upgrade of VC by means of formation of agile high-tech inter-industry production networks within the framework of operating surface and underground mines can reduce social, economic and ecological risks associated with closure of coal mines. Such promising route of VC upgrade is application of methanotrophic bacteria to produce protein to be used as feed-stuff in fish, poultry and cattle breeding, or in production of ferments, lipoids, sterols, antioxidants, pigments and polysaccharides. Closed mines can use recovered methane as a clean energy source. There exist methods of methane utilization from uncontrollable sources, including preliminary treatment and recovery of methane from air-and-methane mixture, or decomposition of methane to hydrogen and acetylene. Separated hydrogen is used in hydrogen fuel cells to generate power to feed the process of methane utilization and to supply external consumers. Despite the recent paradigm of carbon-free energy generation, it is possible to preserve the coal mining industry using the differentiated approach to upgrade of value chains based on flexible technologies with regard to specificity of mining companies.

Keywords: resilience, resilience concept, resilience indicator, resilience in the Russian coal industry, value chains

Procedia PDF Downloads 107

Authors: Mahsa Karimpour, Martin Belusko, Ke Xing, Frank Bruno

Abstract:

Traditionally the embodied energy of design choices which reduce operational energy were assumed to have a negligible impact on the life cycle energy of buildings. However with new buildings having considerably lower operational energy, the significance of embodied energy increases. A life cycle assessment of a population of house designs was conducted in a mild and mixed climate zone. It was determined not only that embodied energy dominates life cycle energy, but that the impact on embodied of design choices was of equal significance to the impact on operational energy.

Keywords: building life cycle energy, embodied energy, energy design measures, low energy buildings

Procedia PDF Downloads 771

Authors: M. Hossain, H. P. Zhu, A. B. Yu

Abstract:

This paper presents a numerical investigation of regime transition of flow of ellipsoidal particles and a comparison with that of spherical particle assembly. Particle assemblies constituting spherical and ellipsoidal particle of 2.5:1 aspect ratio are examined at separate instances in similar flow conditions in a shear cell model that is numerically developed based on the discrete element method. Correlations among elastically scaled stress, kinetically scaled stress, coordination number and volume fraction are investigated, and show important similarities and differences for the spherical and ellipsoidal particle assemblies. In particular, volume fractions at points of regime transition are identified for both types of particles. It is found that compared with spherical particle assembly, ellipsoidal particle assembly has higher volume fraction for the quasistatic to intermediate regime transition and lower volume fraction for the intermediate to inertial regime transition. Finally, the relationship between coordination number and volume fraction shows strikingly distinct features for the two cases, suggesting that different from spherical particles, the effect of the shear rate on the coordination number is not significant for ellipsoidal particles. This work provides a glimpse of currently running work on one of the most attractive scopes of research in this field and has a wide prospect in understanding rheology of more complex shaped particles in light of the strong basis of simpler spherical particle rheology.

Keywords: DEM, granular rheology, non-spherical particles, regime transition

Procedia PDF Downloads 263

Authors: Mohamed Aniss El-Gamal

Abstract:

For decades, the Global South has been facing many challenges in the fields of heritage conservation and local development. These challenges continue to increase due to rapid urbanization in historical cities, thus resulting in complicated juxtaposed contexts of heritage resources and deteriorated dwellings, where slum areas are dotted with heritage structures. While the majority of cases show the incapacity of national and local governments to deal with such contexts, few others managed to demonstrate how different levels of government can play complementary roles in the cooperation with local and international institutions as well as involving local community to achieve an integrated strategy and overcome the challenge. This paper discusses heritage conservation and local development strategies in reference to a number of case studies in cities of the Global south, i.e. Porto Alegre, Agra, Cairo and Mumbai. It further investigates main key aspects of success and failure through cross case studies analysis (Matrix). This study could help create a delineation of an integrated strategy for undertaking future interventions in similar contexts. Integrated strategies are needed to overcome the gap between heritage conservation and local development, maintaining the value of heritage structures and ensuring the quality of life for communities residing in its surroundings.

Keywords: heritage conservation, local development, the global south, regional development

Procedia PDF Downloads 325

Authors: Nora Neuteboom

Abstract:

This study investigates household financial behaviors during unemployment spells in the Netherlands using high-frequency transaction data through a event study specification integrating propensity score matching. In our specification, we contrasted treated individuals, who underwent job loss, with non-treated individuals possessing comparable financial characteristics. The initial onset of unemployment triggers a substantial surge in income, primarily attributed to transition payments, but swiftly drops post-unemployment, with unemployment benefits covering slightly over half of former salary earnings. Despite a re-employment rate of around half within six months, the treatment group experiences a persistent average monthly earnings reduction of approximately 600 EUR by month. Spending patterns fluctuate significantly, surging before unemployment due to transition payments and declining below non-treated individuals post-unemployment, indicating challenges to fully smooth consumption after job loss. Furthermore, our study disentangles the effects of transition payments and liquidity holdings on spending, revealing that transition payments exert a more pronounced and prolonged impact on consumption smoothing than liquidity holdings. Transition payments significantly stimulate spending, particularly in pin and iDEAL categories, contrasting a much smaller relative spending impact of liquidity holdings.

Keywords: household consumption, transaction data, big data, propensity score matching

Procedia PDF Downloads 18

Authors: Benjamin Blat Belmonte, Stephan Rinderknecht

Abstract:

The transition to electric vehicles (EVs) stands at the forefront of innovative strategies designed to address environmental concerns and reduce fossil fuel dependency. As the number of EVs on the roads increases, so too does the potential for their integration into energy markets. This research dives deep into the transformative possibilities of using electric vehicle fleets, specifically electric bus fleets, not just as consumers but as active participants in the energy market. This paper investigates the feasibility and grid effects of electric vehicle fleet operators in the energy market. Our objective centers around a comprehensive exploration of the sector coupling domain, with an emphasis on the economic potential in both electricity and balancing markets. Methodologically, our approach combines data mining techniques with thorough pre-processing, pulling from a rich repository of electricity and balancing market data. Our findings are grounded in the actual operational realities of the bus fleet operator in Darmstadt, Germany. We employ a Mixed Integer Linear Programming (MILP) approach, with the bulk of the computations being processed on the High-Performance Computing (HPC) platform ‘Lichtenbergcluster’. Our findings underscore the compelling economic potential of EV fleets in the energy market. With electric buses becoming more prevalent, the considerable size of these fleets, paired with their substantial battery capacity, opens up new horizons for energy market participation. Notably, our research reveals that economic viability is not the sole advantage. Participating actively in the energy market also translates into pronounced positive effects on grid stabilization. Essentially, EV fleet operators can serve a dual purpose: facilitating transport while simultaneously playing an instrumental role in enhancing grid reliability and resilience. This research highlights the symbiotic relationship between the growth of EV fleets and the stabilization of the energy grid. Such systems could lead to both commercial and ecological advantages, reinforcing the value of electric bus fleets in the broader landscape of sustainable energy solutions. In conclusion, the electrification of transport offers more than just a means to reduce local greenhouse gas emissions. By positioning electric vehicle fleet operators as active participants in the energy market, there lies a powerful opportunity to drive forward the energy transition. This study serves as a testament to the synergistic potential of EV fleets in bolstering both economic viability and grid stabilization, signaling a promising trajectory for future sector coupling endeavors.

Keywords: electric vehicle fleet, sector coupling, optimization, electricity market, balancing market

Procedia PDF Downloads 74

Authors: Aparna Bhat, Rajeshwari Hegde

Abstract:

Renewable energy sources also called non-conventional energy sources that are continuously replenished by natural processes. For example, solar energy, wind energy, bio-energy- bio-fuels grown sustain ably), hydropower etc., are some of the examples of renewable energy sources. A renewable energy system converts the energy found in sunlight, wind, falling-water, sea-waves, geothermal heat, or biomass into a form, we can use such as heat or electricity. Most of the renewable energy comes either directly or indirectly from sun and wind and can never be exhausted, and therefore they are called renewable. This paper presents a review about conventional and renewable energy scenario of India. The paper also presents current status, major achievements and future aspects of renewable energy in India and implementing renewable for the future is also been presented.

Keywords: solar energy, renewabe energy, wind energy, bio-diesel, biomass, feedin

Procedia PDF Downloads 613

Authors: Amin H. Almasria, Rajai Z. Alrousanb, Al-Harith Manasrah

Abstract:

The collapse of a light weight pedestrian bridges due to vehicle collision is investigated and studied in detail using a dynamic nonlinear finite element analysis. Typical bridge widely used in Jordan is studied and modeled under truck collision using one dimensional beam finite element in order to minimize analysis time due to the dynamic nature of the problem. Truck collision with the bridge is simulated at different speeds and locations of collisions using dynamic explicit finite element scheme with material nonlinearity taken into account. Energy absorption of bridge is investigated through principle of energy conservation, where truck kinetic energy is assumed to be stored in the bridge as strain energy. Weak failure points in the bridges were identified, and modifications are proposed in order to strengthen the bridge structure and prevent total collapse. The proposed design modifications on bridge structure were successful in allowing the bridge to fail locally rather than globally and expected to help in saving lives.

Keywords: finite element method, dynamic impact, pedestrian bridges, strain energy, collapse failure

Procedia PDF Downloads 624

Authors: Nchanji Yvonne Kiki, Mala William Armand, Nchanji Eileen Bogweh, Ramcilovik-Suominen Sabaheta, Kotilainen Juha

Abstract:

The Campo Ma'an National Park was created as part of an environmental and biodiversity compensation for the Chad-Cameroon Oil Pipeline Project, which was meant to help alleviate poverty and boost the livelihood of rural communities around the area. This paper examines different strategies and coping mechanisms employed by the indigenous people and local communities to deal with the national and internationally driven conservation policies and initiatives in the case of the Campo Ma'an National Park. While most literature on park management/co-management/nature conservation has focused on the negative implications for local peoples’ livelihoods, fewer studies have investigated the strategies of local people to respond to these policies and renegotiate their position in a way that enables them to continue their traditional livelihoods using the existing local knowledge systems. This study contributes to the current literature by zooming into not only the impacts of nature conservation policies but also the local individual and collective strategies and responses to such policies and initiatives. We employ a qualitative research approach using ethnomethodology and a convivial lens to analyze data collected from October to November 2018. We find that conservation policies have worsened some existing livelihoods on the one hand and constrained livelihood improvement of indigenous people and local communities (IPLC) on the other hand. Nonetheless, the IPLC has devised individual and collective coping mechanisms to deal with these conservation interventions and the negative effects they have caused. Upon exploring these mechanisms and their effectiveness, this study proposes a management approach to conservation centered on both people and nature, based on indigenous and local people's knowledge and practices, promoting nature for and by humans and strengthening both livelihood and conservation. We take inspiration from the convivial conservation approach and thinking by Bucher and Fletcher.

Keywords: conservation policies, national park management, indigenous and local people’s experiences, livelihoods, local knowledge, coping strategies, conviviality

Procedia PDF Downloads 182

Authors: Charmaine Lamiel, Van Hoa Nguyen, Marjorie Baynosa, Jae-Jin Shim

Abstract:

Electrochemical supercapacitors have attracted considerable attention because of their high potential as an efficient energy storage system. The combination of carbon-based material and transition metal oxides/sulfides are studied because they have long and improved cycle life as well as high energy and power densities. In this study, a hierarchical mesoporous carbon sphere/nickel cobalt sulfide (CS/Ni-Co-S) core/shell structure was synthesized using a facile hydrothermal method without any further sulfurization or post-heat treatment. The CS/Ni-Co-S core/shell microstructures exhibited a high capacitance of 724 F g−1 at 2 A g−1 in a 6 M KOH electrolyte. After 2000 charge-discharge cycles, it retained 86.1% of its original capacitance, with high Coulombic efficiency of 97.9%. The electrode exhibited a high energy density of 58.0 Wh kg−1 at an energy density of 1440 W kg−1, and high power density of 7200 W kg−1 at an energy density of 34.2 Wh kg−1. The successful synthesis was considered to be simple and cost-effective which supports the viability of this composite as an alternative activated material for high performance supercapacitors.

Keywords: carbon sphere, electrochemical, hydrothermal, nickel cobalt sulfide, supercapacitor

Procedia PDF Downloads 303

Authors: Vinh Duy Cao, Shima Pilehvar, Anna M. Szczotok, Anna-Lena Kjøniksen

Abstract:

The total energy consumption is dramatically increasing on over the world, especially for building energy consumption where a significant proportion of energy is used for heating and cooling purposes. One of the solutions to reduce the energy consumption for the building is to improve construction techniques and enhance material technology. Recently, microcapsulated phase change materials (MPCM) with high energy storage capacity within the phase transition temperature of the materials is a potential method to conserve and save energy. A new composite materials with high energy storage capacity by mixing MPCM into concrete for passive building technology is the promising candidate to reduce the energy consumption. One of the most untilized building materials for mixing with MPCM is Portland cement concrete. However, the emission of carbon dioxide (CO2) due to producing cement which plays the important role in the global warming is the main drawback of PCC. Accordingly, an environmentally friendly building material, geopolymer, which is synthesized by the reaction between the industrial waste material (aluminosilicate) and a strong alkali activator, is a potential materials to mixing with MPCM. Especially, the effect of MPCM on the thermal and mechanical properties of geopolymer concrete (GPC) is very limited. In this study, high thermal energy storage capacity materials were fabricated by mixing MPCM into geopolymer concrete. This article would investigate the effect of MPCM concentration on thermal and mechanical properties of GPC. The target is to balance the effect of MPCM on improving the thermal performance and maintaining the compressive strength of the geopolymer concrete at an acceptable level for building application.

Keywords: microencapsulated phase change materials, geopolymer concrete, energy storage capacity, thermal performance

Procedia PDF Downloads 309

Authors: Sabina Ngodigha, Roland Gbarabe, Aiyebatonworio Austin

Abstract:

A study of fisher’s knowledge (FK) and community-based fisheries management practices in River Nun estuary was conducted to assess the contribution of FK to fisheries resources conservation. A total of 390 fishers operates in the area of which 221 were interviewed based on having a minimum of 10 years of experience. Community-based fisheries management programme was introduced and implemented by fishermen’s union in 2010 for the sustainable management and conservation of fisheries resources. Local law introduced were: band on the use of mesh size of less than 5cm and band on chemical fishing. Defaulters were made to pay monetary fines ranging from #2,000 to #6,000 while fishers caught using chemicals to fish were arrested and landed over to the police for prosecution. The management method has enhanced conservation of fisheries resources which is a major source of livelihood for the people. Landings increased tremendously resulting in positive increase in the finances of the fishers. It is, therefore, pertinent to introduce community-based laws to check over exploitation of fisheries resources in the Niger Delta.

Keywords: community, conservation, fishers knowledge, local laws, management

Procedia PDF Downloads 277

Authors: Chandan Pramanik, Bikramjit Chanda

Abstract:

Large metal mines operated with open-cast mining methods must transition to underground mining at the conclusion of the operation; however, this requires a period of a difficult time when production convergence due to interference between the two mining methods. A transition model with collaborative mining operations is presented and established in this work, based on the case of the South Kaliapani Underground Project, to address these technical issues of inadequate production security and other mining challenges during the transition phase and beyond. By integrating the technology of the small-scale Drift and Fill method and Highly productive Sub Level Open Stoping at deep section, this hybrid mining concept tries to eliminate major bottlenecks and offers an optimized production profile with the safe and sustainable operation. Considering every geo-mining aspect, this study offers a genuine and precise technical deliberation for the transition from open pit to underground mining.

Keywords: drift and fill, geo-mining aspect, sublevel open stoping, underground mining method

Procedia PDF Downloads 100

Authors: A. Katsman, L. Bloch, Y. Etinger, Y. Kauffmann, B. Pokroy

Abstract:

Various nanosized amorphous alumina thin films in the range of (2.4 - 63.1) nm were deposited onto amorphous carbon and amorphous Si3N4 membrane grids. Transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), X-ray photoelectron spectroscopy (XPS) and differential scanning calorimetry (DSC) techniques were used to probe the size effect on the short range order and the amorphous to crystalline phase transition temperature. It was found that the short-range order changes as a function of size: the fraction of tetrahedral Al sites is greater in thinner amorphous films. This result correlates with the change of amorphous alumina density with the film thickness demonstrated by the reflectivity experiments: the thinner amorphous films have the less density. These effects are discussed in terms of surface reconstruction of the amorphous alumina films. The average atomic binding energy in the thin film layer decreases with decease of the thickness, while the average O-Al interatomic distance increases. The reconstruction of amorphous alumina is induced by the surface reconstruction, and the short range order changes being dependent on the density. Decrease of the surface energy during reconstruction is the driving force of the alumina reconstruction (density change) followed by relaxation process (short range order change). The amorphous to crystalline phase transition temperature measured by DSC rises with the decrease in thickness from 997.6°C for 13.9 nm to 1020.4 °C for 2.7 nm thick. This effect was attributed to the different film densities: formation of nanovoids preceding and accompanying crystallization process influences the crystallization rate, and by these means, the temperature of crystallization peak.

Keywords: amorphous alumina, density, short range order, size effect

Procedia PDF Downloads 466

Authors: Angelina Chiglintseva, Vladislav Shagapov

Abstract:

We know from the geological data that quite sufficient gas reserves are concentrated in hydrates that occur on the Earth and on the ocean floor. Therefore, the development of these sources of energy and the storage of large reserves of gas hydrates is an acute global problem. An advanced technology for utilizing gas is to store it in a gas-hydrate state. Under natural conditions, storage facilities can be established, e.g., in underground reservoirs, where quite large volumes of gas can be conserved compared with reservoirs of pure gas. An analysis of the available experimental data of the kinetics and the mechanism of the gas-hydrate formation process shows the self-conservation effect that allows gas to be stored at negative temperatures and low values of pressures of up to several atmospheres. A theoretical model has been constructed for the gas-hydrate reservoir that represents a unique natural chemical reactor, and the principal possibility of the full extraction of gas from a hydrate due to the thermal reserves of the reservoirs themselves and the surrounding rocks has been analyzed. The influence exerted on the evolution of a gas hydrate reservoir by the reservoir thicknesses and the parameters that determine its initial state (a temperature, pressure, hydrate saturation) has been studied. It has been established that the shortest time of exploitation required by the reservoirs with a thickness of a few meters for the total hydrate decomposition is recorded in the cyclic regime when gas extraction alternated with the subsequent conservation of the gas hydrate deposit. The study was performed by a grant from the Russian Science Foundation (project No.15-11-20022).

Keywords: conservation, equilibrium state, gas hydrate reservoir, rocks

Procedia PDF Downloads 300

Authors: Tahani H. Alluhaybi, Leila Mejrissi

Abstract:

In the present theoretical study, we investigated adiabatically the electronic structure of the (BaNa)+ by the use of the ab initio calculation. We optimized a large atomic GTO basis set for Na and Ba atoms. The (BaNa)+ molecular ion is considered a two-electron thank to a non-empirical pseudo-potentials approach applied to Ba and Na cores with the Core Polarization Potentials operator (CPP). Then, we performed the Full Configuration Interaction (FCI) method. Accordingly, we calculated the adiabatic Potential Energy Curves (PECs) and their spectroscopic constants (well depth De, transition energies Te, the equilibrium distances Re, vibrational constant ⍵e, and anharmonic constant ⍵exe) for 10 electronic states in Σ+ symmetry. Then we determined the vibrational level energies and their spacing, and the electric Permanent Dipole Moments (PDM).

Keywords: Ab initio, dipole moment, non-empirical pseudo-potential, potential energy curves, spectroscopic constants, vibrational energy

Procedia PDF Downloads 113

Authors: G. Nyongombe, Guy L. Kabongo, B. M. Mothudi, M. S. Dhlamini

Abstract:

A series of Transition Metals Oxides (TMOs) doped graphene were synthesized and successfully used as supercapacitor electrode materials. The as-synthesized materials exhibited exceptional electrochemical properties owing to the combined properties of its constituents; high surface area and good conductivity were achieved. Several analytical characterization techniques were employed to investigate the morphology, crystal structure atomic arrangement and elemental chemical state in the materials for which scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were conducted, respectively. Moreover, the electrochemical properties of the as-synthesized materials were examined by performing cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) measurements. Furthermore, the effect of doping concentration on the interlayer distance of the graphene materials and the charge transfer resistance are investigated and correlated to the exceptional current density which was multiplied by a factor of ~80 after TMOs doping in graphene. Finally, the resulting high capacitance obtained confirms the contribution of grapheme exceptional electronic conductivity and large surface area on the electrode materials. Such good-performing electrode materials are highly promising for supercapacitors and other energy storage devices.

Keywords: energy density, graphene, supercapacitors, TMOs

Procedia PDF Downloads 258

Authors: Hsiao-Tien Pao, Yi-Ying Li, Hsin-Chia Fu

Abstract:

This paper addressed the impacts of energy consumption, economic growth, financial development, and population size on environmental degradation using grey relational analysis (GRA) for China, where foreign direct investment (FDI) inflows is the proxy variable for financial development. The more recent historical data during the period 2004–2011 are used, because the use of very old data for data analysis may not be suitable for rapidly developing countries. The results of the GRA indicate that the linkage effects of energy consumption–emissions and GDP–emissions are ranked first and second, respectively. These reveal that energy consumption and economic growth are strongly correlated with emissions. Higher economic growth requires more energy consumption and increasing environmental pollution. Likewise, more efficient energy use needs a higher level of economic development. Therefore, policies to improve energy efficiency and create a low-carbon economy can reduce emissions without hurting economic growth. The finding of FDI–emissions linkage is ranked third. This indicates that China do not apply weak environmental regulations to attract inward FDI. Furthermore, China’s government in attracting inward FDI should strengthen environmental policy. The finding of population–emissions linkage effect is ranked fourth, implying that population size does not directly affect CO₂ emissions, even though China has the world’s largest population, and Chinese people are very economical use of energy-related products. Overall, the energy conservation, improving efficiency, managing demand, and financial development, which aim at curtailing waste of energy, reducing both energy consumption and emissions, and without loss of the country’s competitiveness, can be adopted for developing economies. The GRA is one of the best way to use a lower data to build a dynamic analysis model.

Keywords: China, CO₂ emissions, foreign direct investment, grey relational analysis

Procedia PDF Downloads 403

Authors: Yakup Sahin, Naim Suleyman Ting, Ismail Aksoy

Abstract:

In this paper, a single phase soft switched Zero Voltage Transition and Zero Current Transition (ZVT-ZCT) Power Factor Correction (PFC) boost converter is proposed. In the proposed PFC converter, the main switch turns on with ZVT and turns off with ZCT without any additional voltage or current stresses. Auxiliary switch turns on and off with zero current switching (ZCS). Also, the main diode turns on with zero voltage switching (ZVS) and turns off with ZCS. The proposed converter has features like low cost, simple control and structure. The output current and voltage are controlled by the proposed PFC converter in wide line and load range. The theoretical analysis of converter is clarified and the operating steps are given in detail. The simulation results of converter are obtained for 500 W and 100 kHz. It is observed that the semiconductor devices operate with soft switching (SS) perfectly. So, the switching power losses are minimum. Also, the proposed converter has 0.99 power factor with sinusoidal current shape.

Keywords: power factor correction, zero-voltage transition, zero-current transition, soft switching

Procedia PDF Downloads 803

Authors: M. L. Seretlo-Rangata, T. Sodi, S. Govender

Abstract:

Despite interventions by various governments to regulate water demand and address water scarcity, literature shows that billions of people across the world continue to struggle with access because not everyone contributes equally to conservation efforts. Behavioral factors such as individual and collective aspects of cognition and commitment have been found to play an important role in water conservation. The aim of the present study was to explore the perceptions of community members in the Lephalale area, Limpopo province, towards water conservation with a view to developing an explanatory psychological model on water conservation. Twenty (20) participants who relied on communal taps to access water in Lephalale Local Municipality, Limpopo province, were selected through purposeful sampling. In-depth, semi-structured, individual face-to-face interviews were used to gather data and were analyzed utilizing thematic content analysis (TCA). The research findings revealed that there are various psychological effects of water scarcity on communities, such as emotional distress, interpersonal conflicts and disruptions of daily activities of living. Additionally, the study results showed that the coping strategies developed by participants to deal with water scarcity included adopting alternative water use behaviors as well as adjusting current behaviors and lifestyles. Derived from the study findings, a psychological model of water conservation was developed. The model incorporates some ideas from the Value-Belief-Norm (VBN) theory and the Afrocentric theory. The model suggests that people’s worldviews, including their values, beliefs and culture, are significant determinants of their pro-environmental behaviors. The study concludes by recommending that authorities and policymakers should consider psychological factors when developing water management programs, strategies and interventions with the consultation of psychology experts.

Keywords: water conservation, psychological model, pro-environmental behaviour, conservation psychology, water-use behaviour

Procedia PDF Downloads 71

Authors: Etidel Labidi

Abstract:

Energy efficiency improvement is one of the means to reduce energy consumption and carbon emissions. Recently, some developed countries have implemented the tradable white certificate scheme (TWC) as a new policy instrument based on market approach to support energy efficiency improvements. The major focus of this paper is to compare the White Certificates (TWC) scheme as an innovative policy instrument for energy efficiency improvement to other policy instruments: energy taxes and regulations setting a minimum level of energy efficiency. On the basis of our theoretical discussion and numerical simulation, we show that the white certificates system is the most interesting policy instrument for saving energy because it generates the most important level of energy savings and the least increase in energy service price.

Keywords: energy savings, energy efficiency, energy policy, white certificates

Procedia PDF Downloads 335

Authors: Sabrina Nouri, Abderahmane Ghezal, Said Abboudi, Pierre Spiteri

Abstract:

This paper deals with the numerical study of heat and mass transfer of laminar flow transition at low Prandtl numbers. The model includes the two-directional momentum, the energy and mass transfer equations. These equations are discretized by the finite volume method and solved by a self-made simpler like Fortran code. The effect of governing parameters, namely the Lewis and Prandtl numbers, on the transition of the flow and solute distribution is studied for positive and negative thermal and solutal buoyancy forces ratio. Nusselt and Sherwood numbers are derived for of Prandtl [10⁻²-10¹] and Lewis numbers [1-10⁴]. The results show unicell and multi-cell flow. Solute and flow boundary layers appear for low Prandtl number.

Keywords: natural convection, low Prandtl number, heat and mass transfer, finite volume method

Procedia PDF Downloads 198