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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.
51

Modelling and emulation of industrial electric, pneumatic and hydraulic system

Lorente Zamora, Joanes, Sorarrain Aguirrezabala, Gorka January 2018 (has links)
In recent years, the University of Skövde (HiS) is carrying an advance research in Virtual Commissioning and Emulation. The main goal of the research is to test and verify the control logic of an industrial system virtually before implementing it in the real industry. Literature shows how higher modeling detail level is needed taking into account aspects such as geometry, kinematic, behavior and interfaces. That makes an interesting branch of research for the university and that is the reason why the university is focusing on creating models in component level, where a complete emulation data model is being expanded. The aim of this thesis is to develop a way of modelling electric, hydraulic and pneumatic connections in order to create independent models that can be connected between them for creating systems. Furthermore, an energetic analysis of the system has been done. In the first part of the thesis, a frame of reference and a literature review has been done in order to learn about the fields that the authors are going to work. After that, the simulation models of different electric, pneumatic and hydraulic components have been created with a method, inspired by the producer/consumer concept, which provides a generic solution that allows energy flow in different domains between components in a simple way. Then, different component simulation models have been connected in order to emulate more complex systems. Once the models are done, there have been some test in order to know if all perform as expected. Finally, a discussion of the failures which have been during the project have been done. The experiments done have shown that the proposed and then implemented system has fulfilled all the objectives, unlocking the next step of the emulation development.
52

Energianalys av byggnad i industriell miljö : Energikartläggning med effektiviseringsförslag till byggnad innehå̊llande betningsprocess hos Ovako Hofors AB

Broström, Simon January 2015 (has links)
Världen står inför stora utmaningar där energibehovet ständigt ökar i takt med den globala ekonomin. Något de flesta människor idag känner till är kopplingen mellan energianvändning och negativ påverkan av miljö samt klimat. Sveriges industrier står inför stora utmaningar med ständigt växande global marknad. Följder blir tuffare konkurrenssituation för många företag. Konkurrenssituationen medför att företag flyttar sin verksamhet till länder med lägre produktionskostnader. Kostnader vilka i Sverige har ökat väldigt mycket de senaste decennierna. För att stoppa utflyttning av industriverksamhet krävs stora effektiviseringar i industriföretags energianvändning och förändring av attityd gentemot energianvändning. Studien vilken ligger till grund för rapporten utfördes med energikartläggning av en lokal hos ståltillverkaren Ovako Sweden AB i Hofors. Lokalen där energikartläggningen utförts innehåller en process kallad betning. Kartläggningen grundas på data erhållna av ÅF, vilka även har varit samarbetspartners i studien. Väldigt stora mängder energi används i lokalen, närmare bestämt 14 000 MWh. Störst andel energi går till produktionsprocesser i form av ånga och elektricitet. Ånganvändning står för 8 500 MWh medan elektricitetsanvändning uppgår till 4 500 GWh. För ånga kan kostnadsminskning med 60 % implementeras. Elektricitetskostnader kan med föreslagna metoder minskas med uppskattningsvis 14 %. För uppvärmning av lokalen beräknades användningen uppgå till 2 500 MWh. Användning av uppvärmningsenergi kan minskas drastiskt då byggnaden är väldigt dåligt isolerad och använder mycket energi till uppvärmning. Vid införande av samtliga föreslagna åtgärder för uppvärmning sparas totalt 95 % av uppvärmningskostnader
53

Potential solar power installations within the municipality of Uppsala

Wallentinsson, Måns, Grönlund, Clara, Rustas, Linus, Forsén, Emil January 2018 (has links)
Uppsala municipality has ambitions to reduce greenhouse gas emissions by installing solar power. To do this, the municipality has set a goal to install 30 MWp of solar power by the year 2020, and today 25 MWp has yet to be installed. The objective of this study is to investigate if Uppsala municipality is able to install 25 MWp solar power on municipality owned buildings or if an additional solar park installation is required. This is done through simulations and calculations and results are visualized in QGIS, a geographical information system software. The conclusion of this study is that Uppsala municipality will need a solar park at a magnitude of 0.9 MWp and rooftop installations of 24.1 MWp to reach the goal of 30 MWp. The cost of this installation would be 296 MSEK. The GIS-layers illustrates municipality owned rooftops suitable for solar power installation and module installation proposals. A sensitivity analysis is performed were the type of module is changed, which in turn affects efficiency and module angles. The outcome of the sensitivity analysis is that the type of module and the module efficiency are important parameters that affect the result. Depending on how valuable the land area is, higher module efficiency could be advantageous. Future work could involve an investigation about which type of PV technology that best satisfies Uppsala municipality’s priorities.
54

Water saving comparison study between innovative and conventional cleaning systems for CSP technologies

Verma, Pankaj January 2018 (has links)
No description available.
55

Analys av energi, kostnad och CO2-utsläpp med/utan ångtork och förbränning/sluttäckning med slam rörande slamhantering på ett avloppsreningsverk i Umeå / Energy, cost and CO2-emission analysis with/without a superheated steam dryer and incineration/covering landfill with sludge regarding sludge treatment at a sewage treatment plant in Umeå

Kjellsson, Anton January 2018 (has links)
De ökade deponi- och transportkostnaderna har skapat ett ökat intresse att effektivisera hanteringen av avloppsslam. Umeås allmänna avloppsreningsverk (Vakin) tar emot avloppsvatten från mer än 80 000 hushåll och företag och det mesta leds till reningsverket på Ön. Efter 2020 upphör avtalet med Dåva deponi om att avloppsreningsverket får använda slammet till sluttäckning av deponier. Ett alternativ till deponering är torkning med efterföljande förbränning.Detta examensarbete har genomförts på uppdrag av Vakin och syftet var att kartlägga energiflödena och CO2-utsläppen före och efter en implementering av en ångtork i byggnaderna rörande slamhantering. Även effekter av förbränning respektive deponering av slam har inkluderats. Ett mål var presentera ett systemförslag för hur ångtorken kan implementeras till befintlig anläggning. För att uppnå syftet inhämtades data genom inventering på plats och i projektplaneringsverktyget Projectplace. Därefter beräknades och sammanställdes energibehovet, kostnaden och klimatpåverkan för respektive energiförbrukande enhet i Microsoft Excel Förslaget till implementering av ångtorken är baserat på litteraturdata.Resultatet visar att det årliga energibehovet för slamhantering skulle öka från cirka 2 700 MWh till cirka 3 000 MWh. Vilket resulterar i att den årliga kostnaden för slamhantering ökar från cirka 6,2 miljoner kronor till cirka 7,5 miljoner kronor. Men den årliga klimatpåverkan skulle minska från cirka 930 ton CO2 till cirka 490 ton CO2 med en ångtork. Det årliga elbehovet för slamhantering ökar från inget energibehov till 2 100 MWh vid en installation av en ångtork. Detta eftersom cirka hälften av biogasen som tidigare användes till att producera el- och värmeenergi förväntas användas i ångtorken. Detta resulterar i att den årliga elkostnaden minskar från en intäkt på 650 000 kronor till en kostnad på cirka 4,6 miljoner kronor. Vidare ökar den årliga klimatpåverkan för elen från cirka 10 ton CO2 till cirka 180 ton CO2.Det årliga energibehovet för transporten minskar från cirka 2 700 MWh till cirka 900 MWh vid en installation av en ångtork. Eftersom ångtorken reducerar mängden slam som ska transporteras. Vilket resulterar i att den årliga kostnaden för transporten minskar från cirka 4,1 miljoner kronor till cirka 1,4 miljoner kronor. Även klimatpåverkan för transporten minskar från cirka 720 ton CO2 till cirka 240 ton CO2. Det årliga energibehovet idag är oförändrat när Vakin förbränner det torkade slammet. Eftersom energibehovet för sluttäckning inte beaktats och energibehovet för förbränning av torkat slam är noll. Den årliga kostnaden minskar från cirka 2,8 miljoner kronor till cirka 1,6 miljoner kronor. Eftersom mängden slam minskar mer än vad kostnaden för att förbränna slammet ökar. Den årliga klimatpåverkan minskar från cirka 180 ton CO2 till inget CO2-utsläpp. Eftersom klimatpåverkan att förbränna förnybart biologiskt material är noll. Energikartläggningen av fastigheterna visar att idag förbrukar utrustningen och belysningen rörande slamhantering cirka 760 MWh respektive 25 MWh el. Byggnaderna rörande slamhantering förbrukar idag cirka 1 200 MWh (byggnad 4) respektive 500 MWh (byggnad 5) värmeenergi. Dessa värden är jämförbara med andra liknande slamhanteringsanläggningar. Ur ett hållbarhetsperspektiv rekommenderas att Vakin installerar en ångtork, vilket medför bland annat en minskad årlig transportsträcka och därav reduceras CO2-utsläppen från transporten. Den mest lämpliga integreringen av en ångtork till ett avloppsreningsverk är att upprätthålla en arbetstemperatur för rötkamrarna med värmen från kondensationen av det förångade vattnet, återcirkulera den överhettade ångan som värms av förbränningen av metangasen från rötkamrarna samt blanda torkat slam med blöt slam för att undvika slammets klibbiga fas.
56

Life cycle assessment of villas made by Fiskarhedenvillan, comparison between wood and brick facade

Almsalati, Hussam January 2018 (has links)
Awareness of climate change has resulted in enormous challenges for developed and developing countries. The frightening truth about our environmental situation has led to investigations of the causes of these changes and to obstruct these sources gradually but quickly. The alarming increase of average temperature of the earth has caused much worry around the world. Gas emissions in the atmosphere greatly affect the environment, where CO 2 emissions is one of the most serious factors contributing to the global warming potential. As the building sector emits 40% of global energy use and one-third of global greenhouse gas emissions, engineers must be educated to choose the best materials that lead to reducing CO 2 emissions. This means selecting materials that have less negative impact on the environment and are more “environmentally friendly”. This study shows how much CO 2e emissions are released into the atmosphere from a wooden structure villa that consists of two stories, a storage and a garage, with a total area of 229.6m2. The results of this case will be compared to a second case, where the external wooden siding is replaced with brick veneer. This result of this comparison provides us with a guideline in for how the selected materials impact the environment, illuminating the importance in choosing the right materials according to their CO 2e emission levels. In this way, the building sector can actively work to reduce the environmental impact. To achieve these goals, this study performed via life cycle assessment LCA methodology by using the One-Click LCA program. LCA is identified as a technique to assess the environmental impact and resources used through a product’s life cycle. This study utilized the LCA methodology (cradle to grave), which means starting from the extraction of raw materials, to product production, manufacturing, product usage and its end of life. The study lifespan was estimated to be 50 years. The results of the study verify that the wooden villa is more environmentally friendly than the villa made of brick, where carbon dioxide equivalent emission can be reduced to more than half by utilizing wood. Implementing the life cycle assessment study to any building aids in making the decision to choose the right materials for building according to CO 2e emission. And in this way, the environmental impact caused by the building sector will be greatly reduced.
57

Utvärdering av VVS-system i en befintlig byggnad : Energieffektiviseringsåtgärder för att minska energiförbrukningen i en enfamiljsvilla i Stockholm

Cicek, Dennis January 2018 (has links)
No description available.
58

Energikartläggning av Lumires fordonsflotta : På uppdrag av Luleå Energi AB

Westerberg, Johan January 2018 (has links)
No description available.
59

Predictive Control Strategies for aHeat Pump System with PV and Electrical Storage with Various Boundary Conditions

Johari, Fatemeh January 2018 (has links)
The idea of nearly zero energy building (nZEB) has been emerged from the global trend toward reduction in fossil fuel consumption and green-house gas emission. In spite of different definitions for nZEB, it is vastly known as a grid connected building with highly reduced energy consumption by means of on-site renewable energy production. Accordingly, heat pumps are one of the remarkably efficient heating and cooling technologies considered as the promising components of the nZEBs, specially, when they are associated with the renewable energy systems. However, due to the interaction between heat pump, PV and the grid, the efficiency and the electrical self-consumption of the system strongly depend on the advanced controller strategies such as predictive controllers using price and weather forecast services. Although design of the control algorithms is a very challenging procedure, evaluation of the functionality of these defined algorithms is of paramount importance as well.In this thesis, the robustness of the pre-defined price and weather predictive controllers is studied by testing the performance of a heat pump system for different boundary conditions and compare the results with a reference case study. The base case is a heat pump system for a single-family house with the total heating floor area of 143 m2 and the annual heating demand of 100 kWh/m2.year. The building is located in Norrköping, Sweden and it is assumed that a family of 4 (parents and 2 children) are living in the house. The associated 5.7 kW PV system is mounted on the south oriented roof with the slope of 27˚. Moreover, the system has a storage tank with the total capacity of 180 liter for DHW and a 7.2 kWh battery bank increases the amount of harvested solar energy.The identified methodology of this thesis suggests evaluating the system for the range of variables and boundary conditions, included the climate, thermal properties of the building, orientation and slope of the roof of the building, room set temperature and the occupancy of the building which leads to the various DHW and electricity load profile. Moreover, to study the influences of the controllers on the system, a group of performance indicators are defined. PV self-consumption, solar fraction, final energy use, annual net cost of electricity and seasonal performance factor of the system are considered as the key figures of this study. Next, it aims to do the sensitivity analysis of the system with and without controllers under various boundary conditions. For this purpose, the TRNEdit, as one of the TRNSYS tools which is extended purposely to edit TRNSYS files and manage the parametric simulation studies, is used. Finally, the results from the parametric studies of the system is evaluated to examine the robustness of the controllers.Consequently, the acquired results from the sensitivity analysis of the system with the introduced predictive controllers proves that the performance of the system successfully promotes when it utilizes predictive strategies of PV generation and electricity price. However, the suggested control algorithms need to be slightly modified in order to achieve better results when they operate simultaneously.
60

A Comprehensive PV Systems Installation Guide and Designing a Roof-Based PV System as a Demonstration System for Troubleshooting Errors in PV systems Installations

Hathout, Ahmed January 2018 (has links)
The purpose of the thesis was to make a comprehensive guide for PV systems installers and engineers, using the best practices and following the applicable regulations and standards for the mechanical and electrical installations of PV systems. The guide includes all the different aspects of a PV system installation including different types of roofs and mounting structures, fire safety, height safety and fall protection, installation precautions, electrical and mechanical installations, safety gears and finally system commissioning. The guide was developed by reviewing the various standards and best practices deployed in various countries that are pioneers in PV installations as Germany, UK and the US in the period from 2006-2018.   A troubleshooting errors scheme was conducted to help installers track down operational faults in a PV system. Installers will be able to identify problems of old or newly installed PV systems according to few procedures to resolve operational problems.   In addition, a PV system was designed on the rooftop of Högskolan Dalarna in Sweden. The system will be used as a learning platform for installers in a course that will be introduced on the University’s campus, aimed at educating installers on PV systems installations. The designed system mainly focuses on flat and pitched roofs installations. The system was designed with the main priority to benefit installers working on and installing the system. Performance ratio and energy yield of the system were not emphasized when designing the system. It was specifically designed to match the objectives of the university’s installer’s course to be conducted on the campus. The designed system consists of two sub-arrays with two different mounting structures. The first one was a pitched roof mounting structure installed on a small hut on the university’s rooftop, and the second sub-array was a ballast mounting system directly situated on the roof surface with no penetrations to its surface. The system was designed on Sketchup software as a 3D model, simulated in PVsyst for energy yield forecast and losses evaluations, drawn as a single line electrical diagram on AutoCAD and lastly, a bill of materials was conducted with all the necessary components and parts to install the system on the rooftop.   Results from the simulated system shows a steep drop in energy yield during the winter months, energy losses due to shading effects of approximately 5 % and minimal other system and cables losses were recorded.   A study visit for a pitched roof PV system installation to be carried out by a group of six Swedish students was conducted. A discussion about the installation procedure, major mistakes and lack of practical knowledge by the engineering students were analyzed. Possessing knowledge of PV systems installations is of great importance not only to installers, but to solar design engineers. It is a necessity that engineers poses the fundamentals of installing a PV system and follow the applicable standards and best practices during systems design and execution.

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