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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.
141

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.
142

New concepts for managing diabetes mellitus / Fred Keet

Keet, Fred January 2003 (has links)
Preface - Biotechnology is generally considered to be the wave of the future. To facilitate accurate and rapid development of medication and treatments, it is critical that we are able to simulate the human body. One section of this complex model would be the human energy system. Pharmaceutical companies are currently pouring vast amounts of capital into research regarding general simulation of cellular structures, protein structures and bodily processes. Their aim is to develop treatments and medication for major diseases. Some of these diseases are epidemics like cancer, cardiovascular diseases, stress, obesity, etc. One of the most important causes of these diseases is poor blood glucose control. Current management methods for insulin dependent diabetes are limited to trial and error systems: clearly ineffective and prone to errors. It is critical that better management systems be developed, to ease the diabetic epidemic. The blood glucose control system is one of the major systems in the body, as we are in constant need of energy to facilitate the optimum functioning of the human body. This study makes use of a developed simulation model for the human energy system to ease the management of Diabetes mellitus, which is a malfunction of the human energy system. This dissertation is presented in two parts: The first part discusses the human energy simulation model, and the verification thereof, while the second presents possible applications of this model to ease the management of Diabetes. The human energy system simulation model - This section discusses the development and verification of the model. It also touches on the causes, and current methods, of managing diabetes, as well as the functioning of the human energy system. The human energy model is approached with the conservation of energy in mind. A top down model is developed, using data from independent studies to verify the model. Application of human energy simulation model - The human energy simulation model is of little use if the intended audience cannot use it: people suffering from malfunctioning energy systems. These include people having trouble with obesity, diabetes, cardiovascular disease, etc. To facilitate this, we need to provide a variety of products useable by this group of people. We propose a variety of ways in which the model can be used: Cellular phone applications, Personal digital assistants (PDAs) applications, as well as computer software. By making use of current technology, we generate a basic proof-of-concept application to demonstrate the intended functionality. / MIng (Mechanical Engineering) North-West University, Potchefstroom Campus, 2004
143

New concepts for managing diabetes mellitus / Fred Keet

Keet, Fred January 2003 (has links)
Preface - Biotechnology is generally considered to be the wave of the future. To facilitate accurate and rapid development of medication and treatments, it is critical that we are able to simulate the human body. One section of this complex model would be the human energy system. Pharmaceutical companies are currently pouring vast amounts of capital into research regarding general simulation of cellular structures, protein structures and bodily processes. Their aim is to develop treatments and medication for major diseases. Some of these diseases are epidemics like cancer, cardiovascular diseases, stress, obesity, etc. One of the most important causes of these diseases is poor blood glucose control. Current management methods for insulin dependent diabetes are limited to trial and error systems: clearly ineffective and prone to errors. It is critical that better management systems be developed, to ease the diabetic epidemic. The blood glucose control system is one of the major systems in the body, as we are in constant need of energy to facilitate the optimum functioning of the human body. This study makes use of a developed simulation model for the human energy system to ease the management of Diabetes mellitus, which is a malfunction of the human energy system. This dissertation is presented in two parts: The first part discusses the human energy simulation model, and the verification thereof, while the second presents possible applications of this model to ease the management of Diabetes. The human energy system simulation model - This section discusses the development and verification of the model. It also touches on the causes, and current methods, of managing diabetes, as well as the functioning of the human energy system. The human energy model is approached with the conservation of energy in mind. A top down model is developed, using data from independent studies to verify the model. Application of human energy simulation model - The human energy simulation model is of little use if the intended audience cannot use it: people suffering from malfunctioning energy systems. These include people having trouble with obesity, diabetes, cardiovascular disease, etc. To facilitate this, we need to provide a variety of products useable by this group of people. We propose a variety of ways in which the model can be used: Cellular phone applications, Personal digital assistants (PDAs) applications, as well as computer software. By making use of current technology, we generate a basic proof-of-concept application to demonstrate the intended functionality. / MIng (Mechanical Engineering) North-West University, Potchefstroom Campus, 2004
144

Development of evaluation tools as an approach to pre-design district energy systems : Qualitative modeling and performance simulation using OpenModelica

Faramarzi, Ghazal, Torestam, Malin January 2020 (has links)
Cities and districts contribute to a large fraction of the total energy consumption in Sweden. The residential- and service sector accounted for almost 40% of the total energy consumption in 2018. The increasing urbanization also puts more importance on the energy supply, distribution and consumption in these areas. One way of planning an energy system in urban areas is to have integrated energy systems where synergies between different technologies and energy carriers are utilized. Such a solution can increase the flexibility of the energy system and thus help integrate more intermittent renewable energy sources. The aim of this study was to suggest tools for planning energy systems in districts. This was done by performing a literature review regarding the design of energy systems and the identification of barriers and opportunities for the integration of different production- and distribution technologies. The focus was on systems for heating, cooling and electricity. The proposed tools are three Excel-based modules. The first module is a qualitative model that presents the reviewed technologies and their connections. It also includes synergies between different energy carriers and sectors for consumption and production. The second module is qualitative model related to market mechanisms, juridical, organizational and institutional aspects. The third module is a table containing the barriers and opportunities. Furthermore, relevant stakeholders are identified to be district heating companies, building owners, joint associations, municipalities, district cooling companies and photovoltaic plant owners. The proposed tools can be used in the first stage of planning when the technologies are selected. To show how the suggested tools can be applied, a case study was performed. The study case is a district being planned in Stockholm, Sweden. For the analysis, a model for a hypothetical heating system was required. Two models were developed for the heat supply system using the modelling environment OpenModelica. The main objective of the case study was to compare the techno-economic and environmental performance of different scenarios. Three different scenarios were considered for covering the total heating demand in the district. In the first scenario the total heating demand is covered only by local heat pumps. In the second scenario the space heating demand is covered by heat pump(s) coupled with a thermal energy storage (hot water tank). An electric boiler is used as backup. In the third scenario, the electric boiler is replaced by district heating as backup. A sensitivity analysis was included for different numbers of heat pumps and different sizes of thermal energy storage in the two last scenarios. The economic and environmental results in this study were strongly dependent on the assumptions regarding prices and emission factors. The result of the case study indicates that the third scenario causes the lowest CO2 emissions. An increased size of the thermal energy storage causes a higher compressor electricity consumption thus more emissions. However the total emissions from the system depends on the backup component. For this result, the emission factor related to Swedish electricity mix and the emission factor stated by a district heating company in Stockholm was used. The cheapest alternative in terms of annual operational cost of energy is the first scenario with only heat pumps. However, from the scenarios which also includes thermal energy storage, the second scenario with three heat pumps and a 100 m3 large thermal energy storage, presents the lowest cost. This system design in scenario 2 is only 0.6% more expensive than the first scenario. For the energy prices, the assumption for electricity is based on hourly values from Nordpol and for heat, the values presented in a normal price list from a district heating company is assumed. Regarding the technical performance of the system the result indicates that the contribution from the thermal energy storage as it is modelled in this case study is not significant on anannual basis. However it is observed that a larger thermal energy storage unit covers a higher fraction of the power demand during the hours it is utilized. / Städer och stadsdelar står för en stor del av totala energikonsumtionen i Sverige. Bostads- och servicesektor stod för ungefär 40% av totala energikonsumtionen under 2018. Den ökande urbaniseringen lägger också mer vikt vid energiproduktion, distribution och konsumtionen i dessa områden. Ett alternativ för planering av energisystem i urbana områden är att ha integrerade energisystem där synergier mellan olika teknologier och energibärare kan utnyttjas. Den typen av system skulle kunna öka flexibiliteten i energisystemet och därför förenkla integrering av oförutsägbara förnybara energikällor. Syftet med denna studie var att föreslå verktyg för planering av energisystem i stadsdelar. Detta gjordes genom en litteraturstudie angående utformningen av olika energisystem samt identifiera hinder och möjligheter för att integrera olika produktions- och distributions teknologier. Fokus låg på systemen för värme, kyla och elektricitet. Det föreslagna verktygen är tre Excel baserade moduler. Den första modulen är en qualitative modell som presenterar de studerade teknologier och deras kopplingar. Den innehåller också synergier mellan de olika energibärarna och konsumtions- och produktionssektorn. Den andra modulen är en qualitative modell, men relaterad till marknad mekanismer, juridiska, organisatoriska och institutionella aspekter. Den tredje modulen är en tabell som beskriver hinder och möjligheter för några av teknologierna. Utöver det de relevanta aktörerna identifierades. För värme-, kyla- och elektricitet marknaden är de fjärrvärmeföretagen, fastighetsägare, samfälligheter, kommuner, fjärrkyla företagen, solcells ägare. De föreslagna verktyget kan användas för planering av energisystem i ett första skede när teknologier ska väljas.  En fallstudie genomfördes för att visa hur det föreslagna verktyget kan användas. Fallstudien en stadsdel som planeras i Stockholm, Sverige. För att genomföra en analys behövdes en modell för ett hypotetiskt värmesystem. Två modeller utvecklades för värmesystemet genom att använda modelleringsmiljön OpenModelica. Det huvudsakliga målet med fallstudien var att jämföra den teknoekonomiska- och miljöinriktade prestandan för olika scenarierna. Tre olika scenarier övervägdes för att täcka totala värmebehovet i stadsdelen. I det första scenariot täcks det totala värmebehovet endast av lokala värmepumpar. I andra scenariot täcks värmebehovet för uppvärmning av värmepump(ar) kopplade till en värmelagrings komponent (ackumulatortank). En elpanna användes för reserveffekt. I tredje scenariot är elpannan ersatt av fjärrvärme. En känslighetsanalys var utförd för olika antal värmepumpar kopplade till olika storlekar av värmelagrings-komponenten i de två sista scenarierna. De ekonomiska och miljörelaterade resultatet i den här studien är starkt beroende av antaganden gällande priser och utsläppsfaktorer. Resultatet indikerar att det tredje scenariot har de lägsta CO2 utsläppen. Ökad värmelagringsstorlek bidrar till att värmepumpen förbrukar mer elektricitet och därför ökar de relaterade utsläppen. Däremot beror de totala utsläppen i systemet på vilken reservkraft som används. För dessa resultat användes utsläppsfaktorn för svensk elmix samt utsläppsfaktorn från ett fjärrvärme företag i Stockholm. Den billigaste alternativet gällande årlig driftsenergikostnad är det första scenariot med endast värmepumpar. Däremot, bland de scenarion som innehåller värmelagring, har det andra scenariot med tre värmepumpar och 100m3 stor värmelagringsenhet den lägsta kostnaden. Detta system är endast 0.6% dyrare än det första scenariot. För energipriser har timvärden från Nordpol antagits för elektricitet och för värme har normalprislistan från ett fjärrvärmebolag i Stockholm antagits. Angående den tekniska systemprestandan, indikerar resultatet att bidraget från värmelagringsenheten som den är modellerad i den här fallstudien inte är signifikant på årsbasis. Det observeras emellertid att en större värmelagringsenhet täcker en större andel av effektbehovet under de timmar som enheten används.
145

The specification of a small commercial wind energy conversion system for the South African Antarctic Research Base SANAE IV

Stander, Johan Nico 12 1900 (has links)
Thesis (MScEng (Mechanical and Mechatronic Engineering))--Stellenbosch University, 2008. / The sustainability and economy of the current South African National Antarctic Expedition IV (SANAE IV) base diesel-electric power system are threatened by the current high fuel prices and the environmental pollution reduction obligations. This thesis presents the potential technical, environmental and economical challenges associated with the integration of small wind energy conversion system (WECS) with the current SANAE IV diesel fuelled power system. Criteria derived from technical, environmental and economic assessments are applied in the evaluation of eight commercially available wind turbines as to determine the most technically and economically feasible candidates. Results of the coastal Dronning Maud Land and the local Vesleskarvet cold climate assessments based on long term meteorological data and field data are presented. Field experiments were performed during the 2007-2008 austral summer. These results are applied in the generation of a wind energy resource map and in the derivation of technical wind turbine evaluation criteria. The SANAE IV energy system and the electrical grid assessments performed are based on long term fuel consumption records and 2008 logged data. Assessment results led to the identification of SANAE IV specific avoidable wind turbine grid integration issues. Furthermore, electro-technical criteria derived from these results are applied in the evaluation of the eight selected wind turbines. Conceptual wind turbine integration options and operation modes are also suggested. Wind turbine micro-siting incorporating Vesleskarvet specific climatological, environmental and technical related issues are performed. Issues focusing on wind turbine visual impact, air traffic interference and the spatial Vesleskarvet wind distribution are analysed. Three potential sites suited for the deployment of a single or, in the near future, a cluster of small wind turbines are specified. Economics of the current SANAE IV power system based on the South African economy (May 2008) are analysed. The life cycle economic impact associated with the integration of a small wind turbine with the current SANAE IV power system is quantified. Results of an economic sensitivity analysis are used to predict the performance of the proposed wind-diesel power systems. All wind turbines initially considered will recover their investment costs within 20 years and will yield desirable saving as a result of diesel fuel savings, once integrated with the SANAE IV diesel fuelled power system. Finally, results of the technical and economical evaluation of the selected commercially available wind turbines indicated that the Proven 6 kWrated, Bergey 10 kWrated and Fortis 10 kWrated wind turbines are the most robust and will yield feasible savings.
146

COMBINED BOILER WITH TPV

Björk, Magnus January 2013 (has links)
A TPV-system consists of a hot surface emitting heat radiation on a solar cell with a narrow bandgap.  A unit consisting of a boiler and a TPV-system has been constructed for testing of the performance of TPV cells. The emitter is heated by a fuel consisting of RME-oil. The radiation is collected and concentrated through two reflecting cones formed like a Faberge-egg, with an edge-type optical filter between the cones. The Faberge-egg is treated with electro-polishing in order to obtain a high reflectance of radiation. The edge filter transmits radiation of short wavelengths towards the solar cells and reflects long wavelengths back to the emitter. This increase the temperature of the emitter to prevent the TPV-cells to be overheated. The construction made was working as expected and can be used for further experiments. The performance of the TPV-cells were however very poor because of a low emitter temperature. The main problem was to obtain a good heat transport from the flame to the emitter. It is required that the emitter temperature is considerably increased for justifying a continued work on TPV-systems in combination with boilers.
147

Enhancing the Treatment of Systems Integration in Long-term Energy Models

Welsch, Manuel January 2013 (has links)
Securing access to affordable energy services is of central importance to our societies. To do this sustainably, energy systems design should be – amongst other things – environmentally compliant and reconcile with the integrated management of potentially limiting resources. This work considers the role for so-called 'Smart Grids' to improve the delivery of energy services. It deals with the integration of renewable energy technologies to mitigate climate change. It further demonstrates an approach to harmonise potentially conflicting energy, water and land-use strategies. Each presents particular challenges to energy systems analysis. Computer aided models can help identify energy systems that most effectively meet the multiple demands placed on them. As models constitute a simple abstraction of reality, it is important to ensure that those dynamics that considerably impact results are suitably integrated. In its three parts, this thesis extends long-term energy system models to consider improved integration between: (A) supply and demand through Smart Grids; (B) timeframes by incorporating short-term operating constraints into long-term models; and (C) resource systems by linking multiple modelling tools. In Part A, the thesis explores the potential of Smart Grids to accelerate and improve electrification efforts in developing countries. Further, a long-term energy system model is enhanced to investigate the Smart Grid benefits associated with a closer integration of supply, storage and demand-side options. In Part B, the same model is extended to integrate flexibility requirements. The benefits of this integration are illustrated on an Irish case study on high levels of wind power penetrations. In Part C, an energy model is calibrated to consider climate change scenarios and linkages with land-use and water models. This serves to assess the implications of introducing biofuels on the small island developing state of Mauritius. The thesis demonstrates that too weak integration between models and resource systems can produce significantly diverging results. The system configurations derived may consequently generate different – and potentially erroneous – policy and investment insights. / Säker och prisvärd tillgång till energitjänster är en central fråga för dagens samhällen. För att tillgodose samhällen med hållbara energitjänster bör energisystemen designas för att – bland annat – möta de miljömässiga kraven samt hantera potentiellt begränsade resurser. Den här avhandlingen undersöker de ”smarta” elnätens roll för bättre tillhandahållande av energitjänster. Avhandlingen behandlar integration av förnybar energiteknik för minskad klimatpåverkan samt demonstrerar ett tillvägagångssätt för att förena potentiellt motstridiga energi-, vatten- och markanvändningsstrategier. Dessa uppvisar särskilda utmaningar i energisystemanalyser. Datorstödda modeller kan användas för att identifiera energisystem som på effektivast sätt möter samhällets krav. Datorstödda modeller är, per definition, förenklingar av verkligheten och det är därför viktigt att säkerställa en korrekt representation av det verkliga systemets dynamik. Den här avhandlingen förstärker energisystemmodeller för långsiktsprognoser utifrån tre aspekter: förbättra integrationen av (A) tillgång och efterfrågan genom smarta elnät; (B) olika tidsaspekter genom att inkludera kortsiktiga operativa begränsningar; samt (C) resurssystem genom att sammanlänka olika modelleringsverktyg. I del A utforskades de smarta elnätens potential för att förbättra elektriska system i utvecklingsländer. En befintlig energisystemmodell förstärktes för att behandla smarta elnät och kan därmed fånga fördelarna förknippade med energilagring och energianvändning. I del B utvidgades en energisystemmodell för långsiktsprognoser med flexibilitet för kortsiktiga operativa begränsningar. En fallstudie fokuserad på ett vindkraftsdominerat irländskt elnät genomfördes för att demonstrera fördelarna av modellutvecklingen. I del C kalibrerades en energisystemmodell för att ta klimatscenarier i beaktande samt energisystemets kopplingar till markanvändning och vattenresurssystem. En fallstudie fokuserad på Mauritius energisystem genomfördes för att undersöka konsekvenserna av en potentiell introducering av biobränslen. Avhandlingen demonstrerar att undermålig integration av energimodeller och resurssystem kan leda till avsevärda avvikelser i resultaten. Slutsatser som dras utifrån dessa resultat kan därmed leda till vitt skilda – och potentiellt felaktiga – underlag för investeringar och energipolitiska rekommendationer. / <p>QC 20131118</p>
148

Energiaktiviteter i kunskapshus : En detaljerad kartläggning / Energy activities in educational buildings

Vaghult, Sara, Adolfsson, Anna January 2019 (has links)
Denna studie innefattar en så kallad aktivitetsbaserad energikartläggning som på en detaljerad nivå kartlägger relationen mellan aktiviteter i en skola med användningen av el. Metoden som används baseras på en traditionell metod för energikartläggning men elanvändning kartläggs minut för minut över en hel skolvecka vilket är ovanligt vid energikartläggningar. Data har samlats in för Berzeliusskolan i Linköping under vecka nio och analyserats i förhållande till andra veckor, skolor och nationella mål. Berzeliusskolan är en grund- och gymnasieskola med 1600 elever. Resultatet från studien kan användas för att bättre förutse energianvändning i nya skollokaler och för att prioritera bland möjliga energibesparande åtgärder. Resultatet från kartläggningen visar att de energiaktiviteter som orsakar störst energibehov är fastighetsdrift (33 %), skollunch (25 %) samt rekreation (15 %). Rekreation är definierat som aktiviteter utan direkt koppling till undervisning eller skollunch och innefattar bland annat uppehållsrum, korridorer och personalkök. Alltså är undervisning inte det som påverkar energianvändningen i en skola i första hand.   De viktigaste lärdomarna för genomförande av liknande energikartläggningar är att fokus inte bör ligga på elever och pedagoger utan på byggnaden och skolköket i stort. Eftersom energikartläggningen enbart täcker en skolvecka bör liknande studier genomföras för kunskapshus under skollov för att komplettera denna studie. / This master thesis includes an activity based energy audit in a combined elementary and upper secondary school in Linköping. The audit was conducted at a detailed level to show the connection between activities in schools and energy performance. The focus has largely been on electricity use and the overall method is based on traditional energy audit. The method however is distinct from traditional methods by the fact that electricity is shown minute by minute over a full school week. The results from the study can be used to better foresee energy use in new or remodeled schools. Also, the results is a valuable basis for prioritizing among energy conservation measures connected to similar schools and buildings. The main results from the energy audit shows that building services (33 %), school lunch (25 %) and recreational activities (15 %) are the most important energy activities. It is also found that education itself only contributes to a limited extent. The most important factors in conducting such an activity based energy audit is that focus shouldn’t been on students and faculty but instead on the indoor climate systems and school kitchen. To continue this research, similar audits should be conducted in more schools and during school breaks.
149

Planning production and supply chain in energy intensive process industries

Waldemarsson, Martin January 2014 (has links)
To make a difference among the energy intensive process industries, this dissertation addresses production planning and supply chain planning problems related to industrial energy management issues. The energy issue is turning more and more important from different angles, involving price as well as environmental problems due to climate change leading to political pressure on all energy users. The process industry sector is one of the largest users of energy, and thus important to analyse. Process industries are also capital intensive and operate on large and expensive process equipment, making it imperative to plan their production well in order to reach preferable capacity utilisation. Therefore this dissertation strives to locate the most important energy management issues for the long term profitability of process industries, and investigates the  symbiotic effects of including energy issues in production and supply chain planning. Three different studies at three case companies are carried out, analysed, and presented in five papers. The cases represent the process industry sectors: chemicals, pulp, and steel. Both qualitative case study methodologies as well as quantitative mathematical modelling and optimisation approaches have been practiced. The research questions are analysed from both an energy system and from a production process point of view, separately as well as combined. Energy is somewhat considered to be the main workforce for process industries and this dissertation exemplifies some of its most important dimensions in this context. Several prerequisites for putting energy management on the strategic agenda are located in a specialty chemical industry where the importance of introducing a strategic perspective on energy, the way energy is used, and the possibilities of increasing alternative revenue from utilising by- and/or co-products differently are pinpointed. Approaches for including energy issues in planning processes are also suggested in terms of a MILP model for the entire supply chain of a pulp company, including decisions on purchase and transportation of raw maerials, production allocation, energy mix, and distribution. Another example is presented based on the perspectives of economics of scale and lot sizing through economic order quantity principles in a steel company. By using real company data, energy smart approaches in planning and scheduling are developed with respect to the most important intersections between the production processes and their supporting energy system. The accumulated resource intensity and embedded energy could, and probably should, hence be more fairly  reflected in the product price. The research finally shows some possible impact with including energy issues in a production and supply chain planning model. By planning differently, production prioritisations can be done, and it is not only possible without any large investments, but also prosperous with savings on both energy and money within reach. To conclude, planning of production and supply chain has either a direct or an indirect impact on the energy cost-effectiveness of a company. This dissertation argues that such impact also exists in its mutual form, and is very important when the energy issues are large enough, as they often are in the energy intensive process industry sector. Decision makers should thus beware of the short end of the stick that might be  devastating in the long run, but also aware of all the possibilities that can bring success and prosperity when the future begins.
150

A grid-level unit commitment assessment of high wind penetration and utilization of compressed air energy storage in ERCOT

Garrison, Jared Brett 10 February 2015 (has links)
Emerging integration of renewable energy has prompted a wide range of research on the use of energy storage to compensate for the added uncertainty that accompanies these resources. In the Electric Reliability Council of Texas (ERCOT), compressed air energy storage (CAES) has drawn particular attention because Texas has suitable geology and also lacks appropriate resources and locations for pumped hydroelectric storage (PHS). While there have been studies on incorporation of renewable energy, utilization of energy storage, and dispatch optimization, this is the first body of work to integrate all these subjects along with the proven ability to recreate historical dispatch and price conditions. To quantify the operational behavior, economic feasibility, and environmental impacts of CAES, this work utilized sophisticated unit commitment and dispatch (UC&D) models that determine the least-cost dispatch for meeting a set of grid and generator constraints. This work first addressed the ability of these models to recreate historical dispatch and price conditions through a calibration analysis that incorporated major model improvements such as capacity availability and sophisticated treatment of combined heat and power (CHP) plants. These additions appreciably improved the consistency of the model results when compared to historical ERCOT conditions. An initial UC&D model was used to investigate the impacts on the dispatch of a future high wind generation scenario with the potential to utilize numerous CAES facilities. For all future natural gas prices considered, the addition of CAES led to reduced use of high marginal cost generator types, increased use of base-load generator types, and average reductions in the total operating costs of 3.7 million dollars per week. Additional analyses demonstrated the importance of allowing CAES to participate in all available energy and ancillary services (AS) markets and that a reduction in future thermal capacity would increase the use of CAES. A second UC&D model, which incorporated advanced features like variable marginal heat rates, was used to analyze the influence of future wind generation variability on the dispatch and resulting environmental impacts. This analysis revealed that higher amounts of wind variability led to an increase in the daily net load ramping requirements which resulted in less use of coal and nuclear generators in favor of faster ramping units along with reductions in emissions and water use. The changes to the net load also resulted in increased volatility of the energy and AS prices between daily minimum and maximum levels. These impacts were also found to increase with compounding intensity as higher levels of wind variability were reached. Lastly, the advanced UC&D model was also used to evaluate the operational behavior and potential economic feasibility of a first entrant conventional or adiabatic CAES system. Both storage systems were found to operate in a single mode that enabled very high utilization of their capacity indicating both systems have highly desirable characteristics. The results suggest that there is a positive case for the investment in a first entrant CAES facility in the ERCOT market. / text

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