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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.
1

Vanadium for flow batteries : a design study

Söderkvist, Christoffer January 2013 (has links)
As society strives to transition for sustainable energy generation is it a major challenge to optimize and develop the renewable energy generation that currently exists, both in terms of individual components and their interactions in the entire energy system. The generation from renewable sources is often irregular and not always when the demand arises. By being able to store the excess energy generated and then deliver it when the demand occur results in a more sustainable energy system. Flow batteries are a possible technology for energy storage. An important component of flow batteries are vanadium and to find methods for extracting vanadium in an economical way is an important step in the development of this technology. The idea behind the thesis was therefore to investigate different extraction methods for vanadium where the most promising methods, from an economic and energy perspective, are examined in more detail. The vanadium should then be used to electrolyte in flow batteries. It has also been examined how the cost is affected by moving a planned facility for extraction from the ashes to a developing country with lower personnel costs. In the thesis was also included to explore similar projects on a larger scale conducted in Sweden, how the view of vanadium is from an EU perspective and how flow batteries can be a part of an energy system. The methods considered most promising is extraction from mineral mining and extraction from ashes. A planned production plant has been dimensioned for both processes of production and energy demand is calculated. The study showed that both processes are expected to produce vanadium below current purchase price, which would then contribute to a cheaper production cost of flow batteries. It turned out that the production of vanadium from ash extraction would be significantly reduced by moving the business to a developing country. The operation stage in the mining operation which accounts for the highest energy demand is the size reduction of the ore. In the extraction process of vanadium from ash, it is primarily the fusion furnace and the fly ash filter required which has the highest energy demand. The similar extraction projects investigated was, from ashes, the so-called SOTEX process in Stenungsund and the mineral mining process had the Ranstad project as reference. The EU approach to vanadium is currently that the metal is not classified as a critical raw material but if economic instability would occur in any of the major manufacturing countries it would be considered as a more critical raw material. Flow batteries functioning as energy storage in a PV hybrid system was investigated and it was concluded that flow batteries are technically well suited for energy storage in this type of system. / Då samhället strävar efter att övergå till en hållbar energiproduktion är det en stor utmaning att effektivisera och utveckla den förnyelsebara energiproduktion som idag finns, både när det gäller enskilda komponenter och deras samspel i hela energisystem. Produktion från förnyelsebara energikällor sker ofta ojämnt och inte alltid när behovet uppstår. Genom att kunna lagra den överskottsenergi som produceras och sedan leverera den då behovet uppstår medför det till ett mer hållbart energisystem. Flödesbatterier är en möjlig teknik för lagring av energi. En viktig komponent i flödesbatterierna är vanadin och att hitta metoder för att utvinna vanadin på ett ekonomiskt sätt är ett viktigt steg i utvecklingen av denna teknik. Idén bakom examensarbetet var därför att kartlägga olika utvinningsmetoder för vanadin där de mest lovande metoderna, från ett ekonomiskt och energi perspektiv, undersöks mer utförligt. Vanadinet i sin tur ska sedan användas till elektrolyt i flödesbatterier. Det har även undersökts hur kostnaden påverkas av att flytta en tänkt anläggning för utvinning ur aska till ett utvecklingsland med lägre personalkostnader. I examensarbetet ingick även att undersöka liknande projekt i större skala som bedrivits i Sverige, hur synen på vanadin är ur ett EU perspektiv samt hur flödesbatterier kan vara en del av ett energisystem. De metoder som ansetts mest lovande är utvinning från mineralbrytning samt utvinning ur aska. En tänkt produktionsanläggning har dimensionerats för båda processer där produktionskostnad och energiförbrukning beräknats. Studien visade att båda processerna förväntas kunna producera vanadin under dagens inköpspris vilket då skulle bidra till en billigare produktionskostnad för flödesbatterier. Det visade sig att produktionen av vanadin ur askutvinning skulle minskas avsevärt genom att flytta verksamheten till ett utvecklingsland. Det moment i gruvdriften som står för största energiförbrukningen är storleksreduceringen av den malm som bryts. Vid processen för utvinning av vanadin ur aska är det främst den smältningsugn samt det filter för flygaska som krävs. De liknande projekt som verkat inom utvinning ur aska var den s.k. SOTEX processen i Stenungsund och för mineralbrytning har Ranstad projektet undersökts. EU:s syn på vanadin är i nuläget att metallen inte klassas som en kritisk råvara men om ekonomisk instabilitet skulle uppstå i något av de större tillverkande länderna skulle råvaran klassas som mer kritisk. Flödesbatteri fungerande som energilagring i ett förnyelsebart energisystem undersöktes där slutsatsen var att flödesbatterier tekniskt sett är mycket väl lämpade som energilagring i denna typ av system.
2

Biomass-fuelled PEM FuelCell systems for small andmedium-sized enterprises

Guan, Tingting January 2015 (has links)
Biomass-fuelled proton exchange membrane fuel cells (PEMFCs) offer asolution for replacing fossil fuel for hydrogen production. Through using thebiomass-derived hydrogen as fuel, PEMFCs may become an efficient andsustainable energy system for small and medium-sized enterprises. The aim ofthis thesis is to evaluate the performance and potential applications of biomassfuelledPEMFC systems which are designed to convert biomass to electricity andheat. Biomass-fuelled PEMFC systems are simulated by Aspen plus based ondata collected from experiments and literature.The impact of the quality of the hydrogen-rich gas, anode stoichiometry, CH4content in the biogas and CH4 conversion rate on the performance of the PEMFCis investigated. Also, pinch technology is used to optimize the heat exchangernetwork to improve the power generation and thermal efficiency.For liquid and solid biomass, anaerobic digestion (AD) and gasification (GF),respectively, are relatively viable and developed conversion technologies. ForAD-PEMFC, a steam reformer is also needed to convert biogas to hydrogen-richgas. For 100 kWe generation, the GF-PEMFC system yields a good technicalperformance with 20 % electrical efficiency and 57 % thermal efficiency,whereas the AD-PEMFC system only has 9 % electrical efficiency and 13 %thermal efficiency. This low efficiency is due to the low efficiency of theanaerobic digester (AD) and the high internal heat consumption of the AD andthe steam reformer (SR). For the environmental aspects, the GF-PEMFC systemhas a high CO2 emissions offset factor and the AD-PEMFC system has anefficient land-use.The applications of the biomass-fuelled PEMFC systems are investigated on adairy farm and an olive oil plant. For the dairy farm, manure is used as feedstockto generate biogas through anaerobic digestion. A PEMFC qualified for 40 %electrical efficiency may generate 360 MWh electricity and 680 MWh heat peryear to make a dairy farm with 300 milked cows self-sufficient in a sustainableway. A PEMFC-CHP system designed for an olive oil plant generating annual 50000 m3 solid olive mill waste (SOMW) and 9 000 m3 olive mill waste water(OMW) is simulated based on experimental data from the Biogas2PEM-FCproject1. After the optimization of the heat exchanger network, the PEMFC-CHP  system can generate 194 kW electricity which corresponds to 62 % of the totalelectricity demand of the olive oil plant.The economic performance of the PEMFC and biogas-fuelled PEMFC areassessed roughly including capital, operation &amp; maintenance (O&amp;M) costs of thebiogas plant and the PEMFC-CHP, the cost of heat and electricity, and the valueof the digestate as fertilizer. / <p>QC 20151109</p>
3

ENERGY INVESTIGATION, GÄRTUNA : On the facilities of Astra Zeneca, with suggestions of energy optimizations

Björk, Magnus January 2015 (has links)
AstraZeneca is one of the largest biopharmaceutical companies in the world, and one of the facilities they have is located in Gärtuna, Södertälje. The facility itself is very big with a floor area of 560.000m2 and has a complex energy system. Caverion holds a facility management contract at AstraZenca, hence operates some of the energy system. The energy investigation of this thesis is part of the work of Caverion to ensure a sustainable energy system in Gärtuna. The energy investigation will include mapping of the energy distribution, seeking for potential of improvements and carry out suggestions for energy optimizations. The methods used during the investigation was a literature study, interviews with personnel of both Caverion and AstraZenca, study of the energy system and calculations relevant to the field of study. The mapping of the energy system includes the heat, steam and cooling distribution. When the mapping of the system was done it was clear that the areas with most potential for improvements were the steam and cooling distribution.The mapping of the steam distribution shows a loss of nearly 46% of the steam at year 2014 and the corresponding cost of about 13,640,000 SEK. Even though the steam distribution showed great potential for improvements, it was found that the work of investigating the system would be too difficult for the scope of the thesis. The cooling distribution however is more accessible and the potential is still high due to low coefficient of performance. Two suggestions for energy optimizations were carried out. The first suggestions involves upgraded electric fan motors for some of the cooling towers, and the second suggestion is to modify existing dry coolers in benefit to utilize free cooling during winter period. The fan motor upgrade based on calculations is estimated to result in a yearly energy saving of at least 1526 MWh and a corresponding cost saving of at least 800,000 SEK per year after the pay-off time (9 months). The dry cooler modification based on calculations is estimated to result in a yearly energy saving of 3053 MWh and a yearly cost saving of 2,083,449 SEK after the pay-off period of 5 months. The investigation carried out in this thesis is relevant to both Caverion and AstraZeneca as it points out the areas with potential of improvements and also gives suggestions on energy optimizations that will reduce energy consumption and result in energy cost savings.
4

Diseño de un sistema energético autosustentable mediante la biodigestión de residuos orgánicos para el abastecimiento de energía eléctrica en el mercado Modelo - Chiclayo

Sanchez Manayay, Jesus David January 2023 (has links)
Esta investigación presenta el diseño de un sistema energético autosustentable para el mercado Modelo – Chiclayo, con la finalidad de mitigar los cúmulos de residuos sólidos, la afectación de salud de la población y así mismo aprovechar los residuos orgánicos que diariamente los comerciantes del mercado generan a través de la venta de diferentes productos e insumos; de tal manera que, de la conversión anaeróbica se logre generar energía eléctrica. Se realizó un análisis de cuantitativo, para determinar la demanda máxima del mercado Modelo en validación con los meses, SED EN09 (199,26 kW) y SED EN519 (22,97 kW). En el mercado se clasifica la generación de residuos por las 3,72 TM/día, de lo cual solo en residuos orgánicos es 2,29 TM/día. Utilizando la metodología del proceso de diseño se identifican requisitos, funcionalidad y criterios para evaluar cada alternativa de solución propuesta desde el punto de vista técnico y económico “La alternativa posible es la número 01”, un biodigestor en posición vertical conectados mediante tuberías de acero a un recipiente principal para el almacenamiento del biogás. Los cálculos justificativos del biodigestor y componentes dan como volumen de 4,6 m3 que son dos de la misma capacidad, por lo que el gasómetro tendrá un volumen de 9,2 m3; con esta capacidad se selecciona un generador que funciona con combustible biogás de 375 kW/430kVA. Se realizó el diseño CAD con el detalle de los componentes y medida correspondientes. Al final, se empleó el enfoque VANTIR para llevar a cabo un análisis financiero, el cual arrojó un periodo de recuperación de la inversión de 5 años. Por tanto, se determinó que la inversión es rentable para su implementación. / This research presents the design of a self-sustainable energy system for the Modelo market - Chiclayo, with the purpose of mitigating the accumulations of solid waste, the impact on the health of the population and also taking advantage of the organic waste that the market merchants generate daily a through the sale of different products and supplies; in such a way that electrical energy is generated from the anaerobic conversion. A quantitative analysis was carried out to determine the maximum demand of the Modelo market in validation with the months, SED EN09 (199.26 kW) and SED EN519 (22.97 kW). The solid waste production in the market is classified as 3.72 MT/day, of which only organic waste is 2.29 MT/day. In the market, waste generation is classified as 3.72 Tm/day, of which only organic waste is 2.29 Tm/day. Using the design process methodology, requirements, functionality and criteria are identified to evaluate each proposed alternative solution from the technical and economic point of view "The possible alternative is number 01", a biodigester in vertical position connected by steel pipes to a main vessel for biogas storage. The calculations justifying the biodigester and components give a volume of 4.6 m3 which are two of the same capacity, so the gasometer will have a volume of 9.2 m3; with this capacity a generator running on 375 kW/430kVA biogas fuel is selected. The CAD design was made with the detail of the components and corresponding measurement. In the end, the NPV-IRV approach was used to conduct a financial analysis, which yielded a payback period of 5 years. Therefore, it was determined that the investment is profitable for its implementation.
5

Design of a Sustainable Energy System for a Community Center in rural Mozambique : A Minor Field Study in Mozambique

Säll Magnusson, Emilia, Hahn, Melchior January 2023 (has links)
Access to energy is an important part in the development of most countries and societies, linked to both social and economic growth. Nevertheless, 70% of the population in sub-Saharan Africa does not have access to electricity, which brings consequences to several of these areas. A country to which this largely applies is Mozambique, where the percentage of the country's population that had access to electricity in 2021 was only 31.5%. Working towards the goal of electrifying the least developed countries in a sustainable way, solar technology is believed to have potential to play a vital role, as 60% of the best terrestrial-based global solar resources of the world are located in sub-Saharan Africa. Mini-grids and solar off-grid solutions can further help address the issue of lack of electricity access, especially in rural areas. In previous studies carried out in the village Linga Linga in Mozambique, off-grid solar solutions have been implemented for a small energy demand. With the intention of giving a larger part of the village’s population access to energy services such as light, phone charging and computer access, this thesis will investigate and design an off-grid PV system for a community center in the village. The main research question that will be answered in this report is "How can solar energy be used to supply a community center in the village Linga Linga with a low-cost, reliable and sustainable electricity supply?". To answer the research question, relevant data and information were collected through a literature study on the situation in Mozambique, off-grid PV systems and on PV system components such as inverters, batteries, PV panels and charge controllers. Interviews were also carried out in the village to be able to calculate the expected energy demand of the community center. The community center’s daily energy demand for weekends was estimated to be the highest, at 7 544 Wh with a maximum power demand of 1 230 W. To meet this requirement, the main components were dimensioned so that the system had a maximum power of 2 000 W, a battery storage capacity of 750 Ah and a system voltage of 24 V. For this system, the approximate total cost of the main components was calculated to 56 120 SEK. / Tillgång till energi är en viktig del i utvecklingen av de flesta länder och samhällen, kopplat till både social och ekonomisk tillväxt. Ändå har 70% av befolkningen i Subsahariska Afrika inte tillgång till el, vilket får konsekvenser för flera av dessa områden. Ett land som detta till stor del gäller är Mozambique, där andelen av landets befolkning som hade tillgång till el 2021 endast var 31.5%. I arbetet mot målet att elektrifiera de minst utvecklade länderna på ett hållbart sätt tros solteknik ha potential att spela en avgörande roll, eftersom 60% av världens bästa jordbaserade globala solresurser finns i Subsahariska Afrika. Mininät och solenergilösningar utanför nätet kan ytterligare hjälpa till att lösa problemet med bristande tillgång till elektricitet, särskilt på landsbygden. I tidigare studier utförda i byn Linga Linga i Mozambique har off-grid solenergilösningar implementerats för att tillgodose energibehov för små system. Med avsikten att ge en större del av byns befolkning tillgång till energitjänster som ljus, telefonladdning och datoråtkomst, kommer detta examensarbete att undersöka och designa ett off-grid solcellssystem för ett kultur- och fritidscentrum i byn. Den huvudsakliga forskningsfrågan som kommer att besvaras i denna rapport är "Hur kan solenergi användas för att förse ett kultur- och fritidscentrum i byn Linga Linga med en låg kostnad, pålitlig och hållbar elförsörjning?". För att svara på forskningsfrågan samlades relevant data och information in genom en litteraturstudie om situationen i Mozambique, off-grid solcellssystem och om systemkomponenter såsom växelriktare, batterier, solpaneler och laddningsregulatorer. Intervjuer genomfördes även i byn för att kunna beräkna det förväntade energibehovet för kultur- och fritidscentrumet. Kultur- och fritidscentrumets dagliga energibehov för helger uppskattades vara högst, 7 544 Wh med ett maximalt effektbehov på 1 230 W. För att möta detta krav valdes huvudkomponenterna så att systemet hade en maximal effekt på 2 000 W, en batterilagringskapacitet på 750 Ah och en systemspänning på 24 V. För detta system beräknades den ungefärliga totalkostnaden för huvudkomponenterna till 56 120 SEK.

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