Målet med denna undersökning har varit att finna metoder för rening av struvitpåväxt i rör på Skövde biogasanläggning samt metoder för att undvika uppkomst av struvit. Detta för att man på anläggningen ska kunna öka verkningsgraden och fungera mer resursoptimerat för att på så sätt komma närmare en hållbar samhällsutveckling. Struvit (magnesiumammoniumfosfat hexahydrat) är ett vitt hårt mineral som vanligtvis förekommer i rör, värmeväxlare, pumpar och centrifuger på vattenreningsanläggningar och efter rötningsprocess på biogasanläggningar. Struvit fäller ut som en följd av bland annat pH, temperatur, koncentration och övermättnad. Även rörmaterial kan ha en påverkan på struvitfällning. Undersökningen har genomförts med hjälp av studiebesök samt analys av biogödsel och struvit på Skövde biogasanläggning. Detta för att ta fram den mängd struvit som kan fälla och vart på anläggningen detta sker. En enklare benchmarking har genomförts som har visat att struvitfällning på biogasanläggningar främst uppstår i värmeväxlare och att påväxten där är temperaturberoende. Material och kemikalier har undersökts för att ta fram metoder för rening och hindrande av uppkomst av struvit. Undersökningen har visat på att struvit främst uppkommer i värmeväxlaren och i rörkrökar på anläggningen och att detta är beroende av de pH, övermättnad, temperaturer och höga koncentrationer av fosfor, magnesium och ammonium som finns. Utifrån studien har en teori skapats om att mineralet först uppkommer i kammaren mellan rötkammare och mellantank. Undersökningen visar vidare på att de metoder som är mest effektiva för borttagning av påväxt struvit är att hacka loss mineralen alternativt byta ut rören. För att hindra att påväxt på rör sker rekommenderas att en kombination av metoder genomförs, vilka minskar energianvändningen på anläggningen och hindrar stopp i biogasproduktionen. Kemikalier bör användas om kristallbildning helt ska hindras. Dessa bör tillsättas i nämnda kammare. Till detta bör planerade underhåll ske för att minimera redan påväxt struvit. De rör som byts på anläggningen bör i främsta hand bytas mot plastmaterial. På så sätt kan anläggningen fungera mer resurseffektivt och onödig miljöpåverkan undviks. I studien har endast en grov kostnadsanalys kunnat genomföras. För att vidare understödja ovanstående metod rekommenderas därför en djupare ekonomisk analys genomföras. Denna bör även innefatta studier av kemikaliedos samt undersökning av kontrollplatser för planerade underhåll. / The goal with the study has been to find methods for cleaning and prevention of struvite at Skövde biogasanläggning (biogas plant). This to increase the efficiency and resource optimize the biogas plant and in that way get closer to a sustainable development of the society. Struvite (magnesiumammoniumphosphate hexahydrate) is a white, harsh mineral that commonly occurs in pipes, heat exchangers, pumps, and centrifuges at wastewater plants and after digestion processes at biogas plants. Struvite precipitates as a result of pH, temperatures, concentrations and supersaturation. Pipe material can also contribute. The study has been conducted through study visits and analyses of digestate and struvite at Skövde biogasanläggning to find the amount of struvite that can precipitate and where at the plant this happens. A simple benchmarking has been conducted, which shows that struvite precipitation at biogas plants mainly occurs in heat exchangers and that the fouling is temperature dependent. Materials and chemicals have been studied to find methods for cleaning and prevention of struvite. The study has shown that struvite mainly occurs in the heat exchanger and in pipe bends at the biogas plant and that it is dependent of the pH, supersaturation, temperature and high concentrations of phosphorous, magnesium and ammonium. A theory has been made from the study that the mineral first appears in the chamber between the digesters and heat storage tank. The study further shows that the most effective methods to clean fouling of struvite is to by hand chip the mineral alternatively replace the pipes. To prevent fouling of pipes a combination of methods is recommended, which minimizes the energy usage at the plant and prevent stops in the biogas production. Chemicals should be used if crystallization is to be completely stopped. The chemicals should be added in the above- mentioned chamber. Also planned maintenance should be conducted to minimize fouling. The pipes that are to be replaced should be replaced with pipes made of plastic materials. By doing this the resource efficiency increases and unnecessary environmental impact of the plant is avoided. The study has only included a rough cost analysis. To further support the above- mentioned methods a deeper economic analysis is recommended, which should include a study of chemical dosage and inspection sites for planned maintenance.

This thesis examines the response of air pollutant emissions, water use and carbon emissions from electric power supply systems (electrical grids) to market forces and natural and human disruptions. Specifically, the response of electrical grid operation decisions to emissions pricing and other factors, such as drought restrictions, is examined. The grid of the Electricity Reliability Council of Texas (ERCOT) is used as a source of data, and as a spatial and temporal test-bed. Price signals for NOx emissions have the potential to reduce NOx emissions from the ERCOT grid by up to 50%. In addition to lowering NOx, there are co-benefits to introducing NOx prices, including reductions in the emissions of SOx (24.9% to 70.9%), Hg (16.8% to 81.3%) and CO2 (8.7% to 21.1%). Water consumption was also decreased by 4.3% to 8.2%. The costs of redispatching electricity generation to reduce NOx emissions are, in many scenarios, comparable to conventional control costs. Higher CO2 prices produce many of the same changes in electricity generation as increases in NOx prices, but the simultaneous application of NOx and CO2 pricing produces complex effects. Under stress, such as drought induced water scarcity, dispatching decisions have the potential to increase water availability in regions in which drought is a concern. This dispatching had relatively small impacts on total water consumption summed over all regions of the ERCOT grid. However, the dispatching scenarios resulted in net increases in NOx, SOx, and CO2 emissions rates summed over all regions of the grid, particularly in regions that were absorbing the electricity generation that was exported out of the drought impacted regions. The costs of electricity dispatching, per volume of water consumption reduced in the drought impacted region, was generally greater than the cost of implementing dry cooling in the same facilities at high electricity demand levels, but comparable to dry cooling at low to moderate demand levels. Finally, while changes in total emissions can be used as a surrogate for air quality impacts, actual changes in air pollutant concentrations, such as ozone, exhibit complex spatial and temporal patterns in response to redispatching, including the creation of hot spots of elevated concentrations. / text

This master’s report is an assessment of a theoretical process by which the concepts of sustainability can enter into the conventional system of development, primarily focusing on the physical development and growth of the urban environment. A context-specific definition of sustainability is first derived and then inserted within the classic theory of Diffusion of Innovations in an attempt to articulate the concept of sustainable innovation diffusion. The redevelopment of the Seaholm Power Plant in Austin, Texas is then used as a case study. Specifically, carrying forward previous research on a conceptual plan for adapting the power plant’s dormant condenser infrastructure into a commercial-scale rainwater harvesting system is presented as a demonstration project for promoting sustainable innovations. Applying a systemsthinking approach to resolving the challenges of implementing alternative technologies and practices into the Seaholm case study reveals both the mechanisms for encouraging and the barriers limiting the adoption of sustainable development strategies. / text

No description available.

Edmonton, Alberta, like many other northern cities, has a history of overprotecting its citizens from the climatic elements. Through constructs of climate-control, like pedways and shopping malls, we have severed ourselves from outdoor life and fallen out of love with a season whose inherent beauty and unique attributes have the potential to play a pivotal role in the identity of the city. This thesis studies ways of using architecture and urban design to engage the city dweller across all four seasons. Through the adaptive reuse of the Rossdale power plant and its adjacent lands, the project aims to provide the city of Edmonton with a destination of climatic comfort that begins to thread the disconnect between its citizens and their northern surroundings.

Magistrantūros studijų baigiamasis darbas 52 lapai, 30 paveikslų, 4 lentelės, 41 literatūros šaltiniai. PAGRINDINIAI ŽODŽIAI: Hidrokinetinė energija, turbinos, nepatvankinė technologija, hidroelektrinė. Tiriamojo darbo objektas: Nepatvankinių technologijų panaudojimas upių hidrokinetinės energijos gavybai. Tiriamojo darbo tikslas: Įvertinti nepatvankinių energijos gavybos technologijų ir aplinkosaugos priemonių integracinius suderinamumus. Tiriamojo darbo uždaviniai: 1. Apžvelgti hidrokinetinės energijos panaudojimo taikant nepatvankines technologijas patirtį užsienio šalyse. 2. Apžvelgti hidrokinetinės energijos taikant nepatvankines technologijas panaudojimo siekius Lietuvoje. 3. Išanalizuoti nepatvankinių technologijų schemas. 4. Išanalizuoti nepatvankinių technologijų poveikį vandens ekosistemoms. 5. Įvertinti galimas nepatvankinių technologijų poveikio vandens ekosistemoms sumažinimo priemones. Tiriamojo darbo metodika: literatūros apžvalgos skyrius rašomas referatyviai, analizuojant mokslinius šaltinius. Duomenys tyrimui renkami analizuojant lietuvišką ir užsienio literatūrą, patentus, schemas, didžiausią dėmesį atkreipiant į nepatvankines energijos gavybos technologijas ir jų poveikį aplinkai. Tiriamojo darbo rezultatai: 1. Literatūros analizėje apžvelgta hidrokinetinės energijos panaudojimo taikant nepatvankines technologijas patirtis Lietuvoje, bei užsienyje. 2. Išanalizuotos nepatvankinių technologijų schemos, bei nepatvankinių technologijų poveikis... [toliau žr. visą tekstą] / The final master work consisting of 52 sheets, 30 images, 4 tables, 41 sources of literature. Key words: hydrokinetic energy, turbines, non-affluent technology, hydroelectric power plant. The object of this work: use of non – affluent technologies in extracting hydrokinetic energy out of the rivers. Main goal of this work: estimate the compatibility between non – affluent energy extracting technologies and tools of environment control integrity. Tasks of this work: 1. Overview of the hydrokinetic energy use abroad applying non – affluent technologies. 2. Overview of the hydrokinetic energy implementation and goals into Lithuanian market. 3. Analyses of the schemes about non – affluent technologies. 4. Analyze the impact of non-affluent technologies to eco systems. 5. Estimate the possible tools for decreasing impact of the non-affluent technologies to water eco systems. Methodology of this work: Literature overview charter is written abstractly analyzing scholarly sources. Data for the research was collected by analyzing Lithuanian and foreign literature, licenses, schemes considering non-affluent energy extraction technologies and their impact to the environment. The results of the work: 1. In literature analysis overviewed the experience of the hydrokinetic energy use applying non-affluent technologies in Lithuania and abroad. 2. Analyzed the schemes of the non – affluent technologies and their impact to the eco systems. 3. Estimating the tools for decreasing impact of the... [to full text]

The aim of this thesis is to evaluate how stakeholder participation should be implemented to improve societal acceptance for mega projects. Thereby societal acceptance is seen as a major contributor to project success in this context and involving society in decision-making and two-way dialogue is recognized as the most  effective to achieve this. Based on this research area, a theoretical framework was proposed for the mega project context including prerequisite, process and outcome criteria for stakeholder participation. In this sense, a critical realist ontology stance was assumed to develop the knowledge base and the research was carried out with a qualitative, deductive approach. The case of the coal-power plant “Datteln 4” project and its stakeholder participation forum were used as a unit of analysis for evaluating the proposed framework. From the case, data was collected from interviews with participants as well as forum documents and then analyzed using the template analysis. Based on this evidence, the proposed theoretical framework was adapted to a new case-based framework. The research had three objectives at the outset which were fulfilled in the discussion of the data findings. For the first of these, it was shown that the general link of stakeholder participation and societal acceptance is applicable to the mega project context. A second major finding was that the theoretical framework proposed in literature is relevant, however only to a certain extent. Contextual challenges pertaining to mega projects such as the nature of conflict, long duration and stakeholder positions, however, require more attention to these criteria. Lastly, the necessary further developments for the new case-based framework were discussed including that for mega projects underlying issues of transparency, expectations, power and atmosphere must constantly be considered in stakeholder participation. In conclusion, a stakeholder participation framework is presented that matches the context of mega projects and their need for societal acceptance. Therefore this thesis developed the theoretical knowledge on this underexplored area of project management, and for practitioners it offers criteria to consider during stakeholder participation in mega projects.

Bakalauro darbo tikslas - sukurti bei sukonstruoti testinį saulės elektrinės parametrų stebėjimo sistemos prototipą. Buvo sukurti du elektroninės įrangos įrenginiai, parašytos dvi programos (įrenginio valdymo ir duomenų apdorojimo kompiuteryje). Sistemos pagrindą sudaro AtMega168 mikrovaldiklis, per SPI sąsają renkantis duomenis iš matavimo įrenginių ir per LAN juos perduodantis į kompiuterį apdorojimui ir saugojimui. Kompiuterio programinė įranga veikia dvigubo serverio principu: priima matavimo įrenginio siunčiamus duomenis per UDP portą ir, kitame procese, per TCP portą aptarnauja interneto užklausas, gražindama pagal šabloną sugeneruotą tinklapį su naujausiais apdorotais duomenimis. / The objective of bachelor’s project was to design, build and test prototype of a Solar Power Plant Monitoring system. Two hardware pieces and two software (monitoring program for PC and firmware for hardware) items were designed. System is based on AtMega168 microcontroller collecting data from via SPI bus attached measurement device and transmitting collected data to PC software via LAN for processing, displaying and saving the data. PC software works as dual server: receives data from hardware using and, in separate process, services requests from internet users, returning webpage template with most recent processed data.

Investigations into past accidents at nuclear power generating facilities such as that of Three Mile Island have identified human factors as one of the foremost critical aspects in plant safety. Errors resulting from limitations in human information processing are of particular concern for human-machine interfaces (HMI) in plant control rooms. This project examines the application of Ecological Interface Design (EID) in HMI information displays and the effects on operator situation awareness (SA) for turbine secondary systems based on the Swedish Forsmark 3 boiling-water reactor nuclear power plant. A work domain analysis was performed on the turbine secondary systems yielding part-whole decomposition and abstraction hierarchy models. Information display requirements were subsequently extracted from the models. The resulting EID information displays were implemented in a full-scope simulator and evaluated with six licensed operating crews from the Forsmark 3 plant. Three measures were used to examine SA: self-rated bias, Halden Open Probe Elicitation (HOPE), and Situation Awareness Control Room Inventory (SACRI). The data analysis revealed that operators achieved moderate to good SA; operators unfamiliar with EID information displays were able to develop and maintain comparable levels of SA to operators using traditional forms of single sensor-single indicator (SS-SI) information displays. With sufficient training and experience, operator SA is expected to benefit from the knowledge-based visual elements in the EID information displays. This project was researched in conjunction with the Cognitive Engineering Laboratory at the University of Toronto and the Institute for Energy Technology (IFE) in Halden, Norway.

Fotoelektrinių modulių (FEM) efektyvumas paprastai įvertinamas esant standartinėms tyrimo sąlygoms, tačiau jų veikimas esant realioms lauko sąlygoms yra labai svarbus siekiant kuo tiksliau numatyti jų efektyvumą ir pagaminamos elektros energijos kiekį. / The efficiency of photomodules is evaluated at standard test conditions, but in real conditions their operation is very important in order to foreseen the efficiency and generated energy.