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Generation of wind speed and solar irradiance time series for power plants with storageMauger, Léo January 2016 (has links)
Sizing renewable energy power plants with storage devices needs new resource assessment. Global amount of energy available has to be replaced by time series to depict the resource as a function of time. This paper introduces methodology to generate time series for wind speed and solar irradiance with a granularity between 10minutes and 1seconde. Ground measurements and macro-date from satellite imagery are analyzed and processed to obtain long-term site-specific time series. Because renewable energy forecasting is a growing concern, a second part of the work presents how to modify previously generated profiles in order to obtain forecasts with an expected error.
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On Distributed Balancing of Wind Power Forecast Deviations in Competitive Power SystemsScharff, Richard January 2012 (has links)
Wind power generation does, on the one hand, contribute to a less polluting and more sustainable electric power generation mix. On the other hand, the uncertainty and the variability of the power output do challenge the operation of the power system: hourly variations in wind power generation are hardly predictable in a precise way. To decrease the need for balancing power, it might be beneficial from the overall system-perspective to subject power generating companies to stricter balancing incentives/rules. The way the market is designed has become crucial to exploit the existing flexibility in the power system and to increase the efficiency in its operation: inappropriate market designs can counteract all technical achievements. The work conducted for this thesis is embedded in a project on wind power integration and electricity market design following the aim to develop a simulation tool to analyse the consequences of changes in specific market rules. This thesis analyses wind power variations and forecast errors in the Swedish power system and explores the question whether internal ex-ante self-balancing can efficiently reduce the need for balancing power. Applying internal ex-ante self-balancing, every power generating company re-schedules its own power plants in order to balance its commitments towards other market actors with its newest production forecast. This is done shortly before the hour of delivery. To assess the value of this self-balancing, possible trading and scheduling decisions for power generating companies are modelled based on a hydro-thermal generation portfolio within the framework of the Nordic electricity market design. The model is based on a sequence of mixed-integer linear optimisation problems for the clearing of the different sub-markets. Both the data and the model have an hourly time resolution. In a case study, the model is applied on a simplified test-system. The need of real-time balancing by the transmission system operator, the total variable generation cost of the system, as well as the extent to which the power generating companies re-scheduled their production are then used as indicators to evaluate self-balancing. / <p>QC 20121017</p> / Short-term hydro power planning in power systems with large amounts of wind power / Elektra 36141: Korttidsplanering av vatten-värmekraftsystem vid stora mängder vindkraft: System-perspektivet
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Parallelization of the HIROMB ocean modelWilhelmsson, Tomas January 2002 (has links)
<p>NR 20140805</p>
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The Future of Public Fast Charging : A forecasting of battery supported public fast charging based on a business model perspectiveJeppsson, Måns, Wester, Ivar January 2022 (has links)
With the ever-pressing threat of a climate crisis, the EU has decided to become the first climate-neutral continent by 2050. This in turn will require the road transportation sector to make a transition from fossil dependent to fossil-free vehicles. Sweden has the objective to become net positive in GHG emissions by 2045. To be on track to reach this goal, the GHG emissions of the domestic transport sector must be reduced by 70% by 2030 compared to 2017’s levels. Electric vehicles (EVs) are leading the way in the transition to fossil-free vehicles. To further springboard the diffusion of EVs, the development of a fully functional EV charging network is required. In order to assist the transition to electric vehicles, this report aims to analyse the development of the public fast charging infrastructure in Norrland and Svealand from now to 2030. Additionally, identify geographical areas where an expansion of the public EV fast charging network is needed to cover the future demand of electrified passenger cars. However, there are two major hurdles in building a fast charging network with full coverage. The first is the high monthly costs of providing fast charging which needs a certain utilisation rate to cover the expenses. The second hurdle is the difficulty to receive a grid connection, in certain areas, at the required power output to be able to provide EV fast charging. Therefore, a semi-mobile battery solution used for EV charging is analysed through a business model perspective. The semi-mobile battery solution requires a lower grid connection hence it could be possible to implement public EV fast charging at a lower monthly cost and to develop the public EV fast charging network in otherwise technical difficult areas. A mixed-method approach including both quantitative and qualitative elements was utilised. Primarily, a study of 10 interviews with respondents from a range of different fields connected to EV charging and batteries was performed in combination with a literature review and document analysis. In addition, existing traffic flow data and data of fast-charging infrastructure, were converged via ArcGIS Pro to illustrate the coverage of the fast charging network. Furthermore, projections of the development of the EV fleet were used in order to forecast the flow of EVs in Norrland and Svealand by 2030. Based on these forecasts the future demand of public EV fast charging was analysed. Resulting in a map showing areas of interest, where there will arise a need to expand the charging infrastructure. These areas are Umeå to Piteå, Lycksele with proximity, Bollnäs to Ljusdal and Leksand to Älvdalen. Additionally, the exiting public fast charging infrastructure was identified to require expansion of existing charging stations due to the increased traffic flow of EVs by 2030. The upgrade of existing stations was further assessed to be required to meet both a permanent and seasonal demand, hence making semi-mobile battery supported charging an attractive solution. Furthermore, the design of a semi-mobile battery supporting public EV fast charging was identified to be influenced by situational aspects and that the location-specific conditions were vital in determining profitability for a specific case. For example, the power output in the EV chargers should be adapted to the specifications of the geographical location and the customer segment identified. The energy storage capacity of the battery should also be designed based on the conditions of the location. A connection to the electricity grid exceeding 0.1 MW was also important since it enables the semi-mobile battery to provide additional services to the electricity grid and hence increase revenue streams. Furthermore, FCR-D Up was determined to be the most suitable complementary service to integrate into the system. One major challenge for the semi-mobile battery, based on a business model perspective, is the high costs for semi-mobile batteries and EV fast charging station hardware. However, these costs are projected to continue to decrease and consequently, improve the opportunities for semi-mobile lithium-ion batteries.
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Söktermsdata som ledande indikator för bostadsmarknaden / Search Queries As Leading Indicator Of The Housing MarketAxelius, Björn January 2015 (has links)
Den här studien utvärderar potentialen i söktermsdata från Google som ledande indikator för priser på bostadsmarknaden i Stockholm. Det prediktiva innehållet i söktermsdata från Google Trends jämförs mot en mer klassisk prognosmodell byggd på makroekonomiska variabler. Genom att mäta avvikelsen i en pseudo-prognos redovisas respektive datakällas förmåga till riktiga prognoser. Den huvudsakliga slutsatsen är att det finns resultat som styrker tesen om prediktivt innehåll i Googledata, framförallt för prognoser med horisonter upp till sex månader. Genom att använda Googledata skapas prognoser som har en mindre avvikelse från den faktiska tidsserien är vad modellen byggd på makroekonomiska variabler kan leverera. Resultatet visar på användbarheten i söktermsdata från Google som ledande indikator för priser på bostadsmarknaden i Stockholm. / This study evaluates the potential in using Google search term data as a leading indicator of prices on the real estate market in Stockholm. The predictive content of the search term data from Google Trends is contrasted against a more classic forecasting model using macroeconomic variables. The ability of each data source to generate powerful forecasts is demonstrated by measuring the deviation in a pseudo-forecast. The main finding is that the results support the hypothesis on predictive content in Google data, mainly forecasts with up to six months’ horizon. By using Google data, forecasts can be made with less deviation from the actual time series than forecasts built on macroeconomic variables. The results point to the usability of search term data from Google as a leading indicator for prices on the real estate market in Stockholm.
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Hur strategiska beslut hanteras i sälj- och verksamhetsplaneringsprocessen (S&OP) : En kvalitativ fallstudie som undersöker steg 1 och 2 i sälj- och verksamhetsplaneringsprocessen, genomförd på IKEA / How strategic decisions are handled in the sales and business planning process (S&OP) : A qualitative case study that examines steps 1 and 2 in the sales and business planning process, conducted at IKEAAnderfors, Tilly, Lim, Lovisa, Nyroos, Alma, Bjuringer, Maja January 2021 (has links)
Abstract Title: How strategic decisions are handled in the sales and business planning process (S&OP): A qualitative case study that examines steps 1 and 2 in the sales and business planning process, conducted at IKEA. Authors: Alma Nyroos, Lovisa Lim, Maja Bjuringer & Tilly Anderfors Supervisor: Petra Andersson, LNU Examiner: Hana Hulthén, LNU Background: Planning for today's supply chains has become an increasingly complex challenge. This is because global competition is increasing, at the same time as technology is constantly changing. In order to be able to compete in the market, it is important to make the planning of these chains more effective. One way to plan more efficiently is by using sales and operations planning (S&OP). S&OP's three important flows that are coordinated are materials, finances and information. Today, IKEA feels that they must use some temporary solutions to handle information that comes late in the process and changes the need for different resources. Research question: 1. What are the shortcomings in IKEA's S&OP process with delimitation to step one (data gathering) and two (demand planning)? 2. What are the causes of these shortcomings and how could these shortcomings be rectified? Purpose: The purpose of the study is to identify shortcomings in step one and two in IKEA's S&OP process. This is to be able to contribute with improvement measures in the process. Implementation: This is a case study on IKEA. The data that has been collected in this study are a combination of primary and secondary data. Conclusion: In this study, it emerges that integration and coordination are two important aspects of the S&OP work. It is addressed by most article writers and has also been linked to IKEA's shortcomings. This is linked to the first two steps in the S&OP process. In the investigative organization, gaps were discovered both between internal units and between strategic and operational decisions. For the identified gaps, it is proposed to focus on coordinating the processes in such a way that more people are integrated. Both in terms of integration between different levels (strategic, tactical and operational) and between different units working at the same level. The study also shows that decisions must be integrated into processes in a better way, through better planned information sharing. Keywords: S&OP, demand, forecast, strategic, tactic, operational, integration, coordination.
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Reglering av temperatur via prognosstyrning : Prognosstyrning av byggnad i ÖstersundStrömberg, Daniel January 2022 (has links)
På uppdrag av JAADAB AB har en undersökning huruvida prognosstyrning kan användas för att effektivt reglera värme i en byggnad samt spara energi och ge jämnare innetemperatur genom att använda SMHIs öppna API. I uppdraget ingick även att skapa en modell för att kunna implementera detta i en befintlig byggnad med okända där exakt kännedom om byggandens konstruktion och egenskaper saknas. Arbetet inleddes med en teoristudie gällande byggnadens värmeöverföring samt hur vädret påverkar detta samt där det framgår att byggnaden kan tillgodogöra sig tillförd energi från solinstrålning samt att vind leder till ökade förluster via transmission, ventilation samt läckage. En studie gjordes även gällande prognosstyrning som ledde fram till en väderkompenserad ekvivalent temperatur. Modellen skapades sedan först teoretiskt innan den programmerades med ett koncept där byggnaden beskrivs via parametrar gällande utformning och material där bedömningar kan göras i de fall där exakt kunskap saknas. Modellen använde sedan dessa parametrar och SMHIs API för beräkningar gällande byggandens värmebalans under de nästkommande två dygnen och ta fram en ekvivalent temperatur som ersätter utetemperaturen som ingående temperatur till styrsystemet. Beräkningar gällande vind finns förberedda men är inte inkluderade då inget tillräckligt pålitligt samband mellan vindhastighet och förluster kunde fastställas innan simuleringsstart. Modellen simulerades för en lätt och en tung byggnadskonstruktion via en DUC där utetemperaturen given av SMHI samt den ekvivalenta temperaturen loggades under fyra dygn. Resultatet av simuleringen visade att medeltemperaturen var högre i båda fallen för den ekvivalenta temperaturen. Gällande den tunga byggnadskonstruktionen var topptemperaturen lägre och bottentemperaturen högre för den ekvivalenta temperaturen. Gällande den lätta byggnadskonstruktionen var både topp och bottentemperaturen lägre för den ekvivalenta temperaturen. Arbetet visar tecken på att energibesparingar kan göras men kan inte fastställa att detta kan göras på lång sikt på grund av den korta testperioden som medför att ett begränsat antal förhållanden testats. Förbättringsförslag finns lämnade via mera komplexa beräkningar gällande byggnadens värmeöverföring och påverkan av närmiljö samt flera och längre simuleringar. Förslag på framtida arbeten har lämnats gällande slutförande av vindberäkningar, ytterligare simuleringar, test på verklig byggnad och adderandet av en självlärande loop. / On behalf of JAADAB AB, a study has been conducted on whether forecast control can be used to effectively regulate heat in a building to save energy and provide a more even indoor temperature by using SMHI's open API. The assignment also included creating a model to be able to implement this in an existing building where details regarding the construction and properties of the building are unknown. The work began with a theoretical study regarding the building's heat transfer and how the weather affects the heat transfer where it appears that the building can utilize the supplied energy from solar radiation and that wind leads to increased losses via transmission, ventilation and leakage. A study was also done regarding forecast control which led to a weather-compensated equivalent temperature. The model was then first created theoretically before it was programmed with a concept where the building is described via parameters regarding design and materials where assessments can be made in cases where exact knowledge of the values is lacking. The model then used the submitted parameters and SMHI's API for calculations regarding the construction's heat balance during the next two days to produce an equivalent temperature that replaces the outdoor temperature as the input temperature to the control system. Calculations regarding wind are prepared but are not included as no sufficiently reliable connection between wind speed and losses could be established before the start of the simulation. The model was simulated for a light and a heavy building construction via the use of a DUC where the outdoor temperature was given by SMHI and the equivalent temperature were logged for four days. The result of the simulation showed that the average temperature was higher in both cases for the equivalent temperature. Regarding the heavy building construction, the highest temperature was lower and the bottom temperature higher for the equivalent temperature. Regarding the lightweight building construction, both the top and bottom temperatures were lower for the equivalent temperature. The work shows signs that energy savings can be made but it cannot be established that this can be done in the long term due to the short test period which means that a limited number of conditions have been tested. Suggestions for improvement have been submitted via more complex calculations regarding the building's heat transfer and impact on the local environment around the building as well as several further simulations with over more extended periods of time. Suggestions for future work have been submitted regarding the completion of wind calculations, additional simulations, tests on real building and the addition of a self-learning loop.
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Zur Schätzung von Häufigkeitstrends von extremen Wetter- und KlimaereignissenMudelsee, Manfred, Börngen, Michael, Tetzlaff, Gerd 03 January 2017 (has links)
Die Vorteile der Kernschätzung gegenüber dem Abzählen von Ereignissen in Zeitintervallen werden dargestellt. Für das beiden Methoden gemeinsame Glättungsproblem gestattet die Kreuzvalidierung eine Lösung. Für die Hochwasserereignisse der Oder im Zeitraum 1350 bis 1850 wird eine Abnahme der Häufigkeit nach ca. 1675 gefunden; weitergehende Aussagen bedingen eine Homogenisierung der Daten. Die dargestellte Methodik wird gegenwärtig in das Computerprogramm XTREND implementiert. / The advantages of kernel estimation over counting of events within time intervals are shown. Cross validation offers a solution for the smoothing problem which is common to both methods. As regards ooding events of the river Oder in 1350 to 1850, a decrease in the frequency after about 1675 is found. More detailed results demand homogenized data. The method is currently being implemented into the computer program XTREND.
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Ein numerisches Modell zur lokalen Nebelvorhersage. Teil 1: Parametrisierte Mikrophysik und StrahlungTrautmann, Thomas, Bott, Andreas 03 January 2017 (has links)
Die Modellkomponenten für parametrisierteWolkenphysik, Strahlung und Sichtweitenbestimmung im Nebelvorhersagemodell PAFOG, das kürzlich in Zusammenarbeit mit dem Deutschen Wetterdienst als lokales Vorhersagesystem entwickelt wurde und für die Kurzfristprognose
eingesetzt werden kann, werden vorgestellt. Die Modellphilosophie orientiert sich an einer mathematisch-physikalisch fundierten Beschreibung der beteiligten meteorologischen Prozesse, deren Einzelheiten in dieser Arbeit diskutiert werden. / This paper presents the model components for parameterized cloud physics, radiation and visibility determination as implemented in the local forecast model PAFOG. PAFOG has been recently developed in cooperation with the GermanWeather Service DWD. PAFOG can be employed for short-range forecasts of radiation fog and visibility. The philosophy of the model strongly emphasizes a mathematically and physically based formulation of the involved meteorological processes the details of which are discussed in this paper.
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Ein numerisches Modell zur lokalen Nebelvorhersage. Teil 2: Behandlung von Erdboden und VegetationTrautmann, Thomas, Bott, Andreas 03 January 2017 (has links)
Die im Nebelvorhersagemodell PAFOG enthaltenen Modellkomponenten für parametrisierte Wolkenphysik, Strahlung und Sichtweitenbestimmung wurden durch Module zur Beschreibung der Interaktion mit dem Boden und der Vegetation ergänzt. Das auf diese
Weise komplettierte Modellsystem PAFOG-V kann dazu verwendet werden, das lokale Auftreten von Strahlungsnebel und niedriger stratiformer Bewölkung vorherzusagen. / The paper presents an extension of the model components for parameterized cloud physics, radiation and visibility determination as implemented in the local forecast model PAFOG to include the interaction with the soil and the vegetation. The resulting forecast system PAFOG-V can be used to predict local events of radiation fogs and of low level stratiform clouds.
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