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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.
31

Techno-economic study of grid connected residential PV system with battery storage - A review of the Local System Operator (LSO) model

Kabir, MD Ahsan January 2017 (has links)
The grid connected solar PV system with battery storage is one of the promising alternativeenergy solutions for electricity consumers. The Local System Operator (LSO) will be a newactor to operate its own energy system by integrating PV and battery system with other technicalsolutions. This thesis investigates the technical and economic viability of a grid connected PVsystem with battery storage in behind-the-meter approach for aggregated residential load toassess the LSO model for the present conditions in Sweden.The system model is developed using the System Advisory Model (SAM) – a simulationsoftware for renewable energy system analysis. The PV system model is designed using solarirradiation profile and fifty multi-dwelling aggregated residential load data from Sweden. Theappropriate design inputs of solar PV module, inverter and system loss are taken from previousstudies. The electricity price is analysed from the comparative study of Nord-pool wholesaleprice, market retail price and distribution grid tariffs. The financial metrics such as discountrate, inflation rate, system cost and currently available PV incentives are considered to make anaccurate model. To help with the assessment, three cases are formed; the first case representsonly the PV system and the other cases include storage - using a lithium-ion or lead-acid battery.This comparative study helps to determine the optimum PV and battery size at two differentlocations in Sweden.The optimum net present value (NPV) and profitability index (PI) is found at the 40 kW PVand 3 kWh battery system at Karlstad, Sweden. The optimum case is considered for furtherinvestigation to evaluate the system life time energy profile, electricity bill saving capabilityand battery performance. The system peak shaving potential is investigated by making twoother scenarios with higher battery capacity. Sensitivity analysis is also performed to assess thesystem’s technical and financial input parameters. The system capacity factor at the site locationis found as an influential parameter to the annual production and profitability. The optimumsize of PV system with a lithium-ion battery investment is found feasible for the LSO realimplementation only considering the current PV incentives and electricity price in Sweden. Thereport concludes with the assessment, the technical and economic feasibility of the studied PVand battery storage system profitability depends on the system site location, residential loadsize, consumer electricity cost and available PV incentives. / solcellsystem (PV) med batterilagring är en lovande alternativenergilösning förslutkonsumenten. Den 'local system operator', LSO, blir en ny aktör som driver egetenergisystem genom att integrera PV- och batterisystem med andra tekniska lösningar. Dennaavhandling undersöker det tekniska och ekonomiska genomförbarhetet i ett nätanslutet PVsystem med batterilagring i 'bakom mätaren' scenario för aggregerade bostäder i ettflerbostadshus, för att urvärdera LSO modellen.Systemmodellen är utvecklat med 'system advisory model' (rådgivande modell), SAM, ettsimuleringsprogram för förnybara energisystem. PV systemparametrarna beräknas med hänsyntill väderprofiler och lastdata från Sverige. Lämpliga parametrar för solcellsmoduler, omriktareoch systemförluster tas från tidigare studier. Slutkonsumenternas elpriser analyseras frånjämförande studie av NordPool grosshandelspris, konsumentpris och distributionnätstariffer.Finansiella mått såsom system kostnad, rabatt och inflationstakten och tillgängliga incitamentför PV investeringar används för att göra modellen noggrannare. Tre fall undersöks; det förstarepresenterar systemet med bara PV, och de övriga fallen lägger till lagring, genom antingenlitiumjon eller bly-syre batterier. Denna jämförande studie är ett underlag för att bestämma denoptimala PV och batteristorleken för anläggninar på två olika område i Sverige.Den optimala netto nuvarande värde (NPV) och lönsamhet index (PI) är på 40 kW PV systemetoch 3 kWh batteri på Karlstad, Sverige. Ytterligare undersökning av detta fall används för attutvärdera energiprofilen under systemets livstid, möjlighet till minskad elräkning, och batterietsprestanda. Potential för utjämning av systemets topplast utreds genom att skapa två andrascenarier med högre batterikapacitet. Känslighetsanalys utförs också för att bedöma de tekniskaoch ekonomiska parametrarna. Den optimuma storleken på PV system med ett litium-jonbatterifinns rimligt för LSO riktiga genomförande med tanke på incitamenten. Simuleringsresultatenoch systemkonsekvenserna av LSO modellen diskuteras. Rapporten visar att den tekniska ochekonomiska genomförbarheten av det studerade PV systemet med litium-jon batteri beror påslutkonsumentelpriset, PV incitament och globala trender i kostnaderna försystemkomponenter, samt på valet av lämplig plats med en effektiv analys av väder profil ochsystemetförluster.
32

Value Creation with Battery Energy Storage Systems and a Service-based Business Model Approach : A study of economic performance and business model opportunities for Battery Energy Storage Systems in high power machine applications / Värdeskapande med Stationära Batterisystem i Kombination med en Tjänstfokuserad Affärsmodellsstrategi

Garton, Louise January 2022 (has links)
Energy Storage Battery Systems (BESS) will have an important role in the transformation from conventional energy systems to the decentralized energy systems of the future with a larger share of renewable energy sources. At the same time, the high investment costs for batteries are a challenge to the development and transformation of the Swedish energy system. This study examines the technical and economic performance of a battery system in a case study, where it is connected to a waste vacuum machine with daily power peaks that are higher than the base demand. The purpose of the battery system is to combine it for peak shaving and for Svenska Kraftnät's market for grid services. This study also examines how a service-based business model, where the ownership of the battery is transferred to a third party, affects value proposition, value creation and value capture. The results from this study show that actual cost savings are realized through peak shaving as well as opportunities for revenue by offering the battery for grid services. Furthermore, scenario modeling shows on certain operational insights, that at a certain level of compensation for grid services, it is most profitable to perform as high peak shaving as possible. Offering the battery as a service is shown to provide additional benefits for customers and companies, while society and the environment benefit above all from the battery technology itself. / Stationära batterisystem (BESS) kommer ha en viktig roll i transformationen från konventionella energisystem till framtidens decentraliserade energisystem med större andel förnyelsebara energikällor. Samtidigt är de höga investeringskostnaderna för batterier ett hinder för utvecklingen och transformationen av det svenska energisystemet. Denna studie undersöker ett batterisystems tekniska och ekonomiska prestanda i en case studie, där det är kopplat till en sopsug med dagliga effekttoppar som är högre en basbehovet. Syftet med batterisystemet är att kombinera det för effektkapning och för Svenska Kraftnäts balansmarknad. Denna studie undersöker även hur en tjänstebaserad affärsmodell, där ägarskapet av batteriet flyttas till en tredje part påverkar värdeerbjudande, värdeskapande och värdefångst. Resultatet från denna studie visar att faktiska kostnadsbesparingar blir realiserade genom effektkapning samt möjligheter till intäkter genom att erbjuda batteriet för stödtjänster. Vidare visar scenariomodellering på vissa operationella insikter, att det till en viss nivå av ersättning för stödtjänster är det mest lönsamt att utföra så hög effektkapning som möjligt. Att erbjuda batteriet som tjänst visas ge ytterligare fördelar för kunder och företag, medan samhället och miljön gynnas framför allt av själva batteritekniken.
33

Peak shaving optimisation in school kitchens : A machine learning approach

Alhoush, George, Edvardsson, Emil January 2022 (has links)
With the increasing electrification of todays society the electrical grid is experiencing increasing pressure from demand. One factor that affects the stability of the grid are the time intervals at which power demand is at its highest which is referred to as peak demand. This project was conducted in order to reduce the peak demand through a process called peak shaving in order to relieve some of this pressure through the use of batteries and renewable energy. By doing so, the user of such systems could reduce the installation cost of their electrical infrastructure as well as the electrical billing. Peak shaving in this project was implemented using machine learning algorithms that predicted the daily power consumption in school kitchens with help of their food menus, which were then fed to an algorithm to steer a battery according to the results. All of these project findings are compared to another system installed by a company to decide whether the algorithm has the right accuracy and performance. The results of the simulations were promising as the algorithm was able to detect the vast majority of the peaks and perform peak shaving intelligently. Based on the graphs and values presented in this report, it can be concluded that the algorithm is ready to be implemented in the real world with the potential to contribute to a long-term sustainable electrical grid while saving money for the user.
34

Simuleringsbaserad analys av toppeffektreducering med batterisystem i lokalnät / Simulation based analysis of peak shaving with battery energy storage system in residential distribution network

Hamanee, Sahaphol January 2019 (has links)
In this thesis, a simulation model developed in MATLAB® in consideration of system losses based on lithium ion-battery is presented. The purpose of the simulation model is to investigate peak shaving potential in the residential distribution network. In other word to determine an optimal threshold limit and battery capacity depending on if the battery system is placed at the transformer or household level. In the report there were economic calculations executed showing that profitability of investing in a battery system depends on the threshold limit and battery capacity. / I denna rapport presenteras analys av toppeffektreducering med ett simuleringsprogram baserad på litium-jon batteri med hänsyn till systemförlust. Simuleringsmodellen är uppbyggd i MATLAB® där metoder som Coulomb counting implementerades. Syftet med simuleringsprogrammet är att definiera en optimal tröskelgräns samt batterikapacitet på transformator- och hushållsnivån. I rapporten utfördes ekonomiska beräkningar som tyder på att lönsamheten för investering av ett batterisystem beror på tröskelgräns och batterikapacitet.
35

Determining the Technical Potential of Demand Response on the Åland Islands / Utvärdering av den tekniska potentialen för efterfrågeflexibilitet på Åland

Nordlund, Edvard, Lind, Emil January 2021 (has links)
With increasing intermittency from renewable energy production, such as solar and wind power, the need for increased flexibility is quickly arising. The Åland Islands have an ambitious energy transition agenda with the goal of having a 100 % renewable energy system. Since there is no possibility of hydropower acting as regulatory power on Åland, reaching the goal is a challenging task. Increasing flexibility can be achieved by either implementing energy storage in the system or by matching the demand with the production.   The purpose of this study was to estimate and evaluate the technical potential of demand response (DR) on Åland, both in 2019 and for a scenario in 2030 when domestic production of wind and solar have increased. Six areas of interest were identified; electric heating, refrigeration processes, lighting, ventilation and air conditioning, electric vehicles and industries. Electricity import from Sweden to Åland was examined since high import coincides with either low domestic renewable production or high consumption. Import is therefore a good indicator for when flexibility is most required.  The results show that the technical potential of DR on Åland can lower the maximum electricity import from Sweden by 18 % in 2019. 4.3 % of the total import can be moved to times when there is less stress on the grid. Electric heating is the biggest contributor, and can by itself lower the import with three fourths of the total reduction. The domestic renewable production for 2019 is too low for DR to have an effect on the self-sufficiency. In 2030, the self-sufficiency and utilization of domestic renewable production could be increased with 4.2-9.9 % and 5.4-12 % respectively when using DR, depending on if vehicle-to-grid is implemented on a large scale or not. The cost of implementing DR is still uncertain, and varies between different resources. Nonetheless, DR in electric heating is presumably a less expensive alternative in comparison to batteries, while providing a similar service.
36

Investigation of energy management topologies for forming presses with electro hydrostatic drivetrains

Reidl, Tim, Weber, Jürgen, Ihlenfeldt, Steffen 25 June 2020 (has links)
Recent Power On Demand approaches, realized by using speed and/or displacement variable pump units, led to a significant increase of energy efficiency on hydraulic forming presses. In this paper we follow up on this development by laying the focus on the energy management and storage design of such machinery. With a derived fluidtronical model, we compare five different topologies that supply and manage the power flow for a forming press with die cushion. Our evaluation criteria are: energy consumption, minimization of the infeed power, and qualitative costs. For a representative forming cycle, the losses occurring on each of the drivetrain components and the power electronics accessory are derived in detail. We expect that this research will lead to deeper investigation of more intelligent energy management systems that use multiple storages in an optimal way and further learn and adapt during operation.
37

Optimization and techno-economic study of a PV Battery system for a vacation home in Sweden

Coll Matas, Joaquin January 2020 (has links)
Currently, Sälen area in Sweden is finding issues in the power grid due to an irregular load profile with high peak power demand and an infrastructure that is becoming undersized. Distributed PV-battery systems are considered a possible solution to solve this problem.A PV-battery system for a typical vacation home in this town is designed and optimized to give the best economical solution to the homeowner. Then, a techno-economic evaluation of the system is performed. A photovoltaic system and an only grid connected system are also simulated and compared. Finally, a sensitivity analysis is performed on different simulation inputs.HOMER Grid software is used to simulate and size the system. Firstly, a pre-sized system is modelled using average or typical market prices and component characteristics. Afterwards, real market components that fit into the pre-sized model are modelled to get a real system design. The optimized design includes a PV system of 13 kW, a BYD lithium ion battery of 5.1 kWh capacity and a Sungrow hybrid inverter of 10 kW.The economic evaluation of the system indicates that, with current market prices and subsidies, the optimized system is the most economical solution for the homeowner compared to the other systems. In the sensitivity analysis, a significant risk for the profitability of the system is found on the compensation from selling electricity to the grid.The technical evaluation of the system indicates that the battery provides a significant peak-shaving effect that can benefit the power grid. However, large solar energy sales to the grid with high power peaks that could cause instability issues are observed.
38

Active Phase Balancing and Battery Systems for Peak Power Reduction in Residential Real Estate : An Economic Feasibility Study / Aktiv Fasbalansering och Batterier för Effekttoppsreducering i Bostadsfastigheter : En Ekonomisk Genomförbarhetsstudie

Westerberg, Jacob January 2020 (has links)
Research has shown that three-phase balancing alone can improve the operation of secondary distribution networks and that the addition of energy storage to the phase balancing power electronics further helps to alleviate the negative effects of phase unbalances. However, less attention has been paid to the economic potential of said technologies and particularly for loadside implementation. It appears that the deployment of phase balancers, with or without energy storage, is indeed hampered by uncertainty related to its economic feasibility, despite both technologies being commercially available. This thesis therefore aims to assess and compare the economic feasibility of the two configurations for peak shaving purposes in the context of residential property loads in Sweden. The assessment was performed using a specially developed deterministic techno-economic model taking into consideration historical load data from three Swedish real estate, cost estimations for a range of alternatives used when sizing the systems, applicable tariffs and fees for electricity and its distribution as well as technical parameters such as the capacities and efficiencies of the involved components. A novel approach was taken by linearly extrapolating the three load profiles into three sets of 91 synthesized load profiles to enable a larger dataset for analysis. The net present values generated for each set were then graphed and analyzed per original real estate. The results showed that both configurations can be economically feasible, but only under certain conditions. A phase balancer alone was found to be feasible for real estate whose peak currents are distinctly unbalanced and exceed 50 A, with the best expected rate of return for profiles exceeding 63 A since they enable a tariff switch. The combined system was found to be even more contingent on the tariff switch and therefore only feasible for peaks above 63 A. A substantial difference in the initial investment further makes the single phase balancer the preferred choice, unless the discount rate is as low as 2 % or less. On this basis, potential investors need to assess the state of unbalance of their loads and perform their own calculation based their load profile, cost of capital and applicable tariffs. / Tidigare forskning har visat att fasbalansering enskilt kan förbättra driften hos lokala distributionsnät och att ett batterisystem i tillägg till fasbalanserarens kraftelektronik ytterligare kan minska de negativa effekterna av fasobalanser. Däremot har mindre uppmärksamhet riktats mot den ekonomiska genomförbarheten hos dessa teknologier och i synnerhet för implementation på lastens sida av elmätaren. Det tycks vara så att spridningen av fasbalanserare, med eller utan energilagring, hindras av osäkerheten kring dess ekonomiska potential trots att båda teknologierna är kommersiellt tillgängliga. Detta arbete ämnar därför att värdera och jämföra den ekonomiska nyttan hos de två konfigurationerna vid toppreducering av fastighetselen i svenska bostadsfastigheter. Värderingen utfördes med hjälp av en särskilt utvecklad deterministisk tekno-ekonomisk modell som beaktade historiska lastdata från tre svenska fastigheter, kostnadsuppskattningar för en uppsättning av konfigurationer som användes vid dimensionering av systemen, applicerbara tariffer och avgifter för elektricitet och dess distribution samt tekniska parametrar såsom kapaciteter och verkningsgrader för de olika komponenterna. Ett annorlunda tillvägagångssätt tillämpades vidare för att utöka datamängden genom linjär extrapolation av lastprofilerna, vilket resulterade i tre uppsättningar av 91 syntetiserade lastprofiler. Nettonuvärdet beräknades följaktligen för varje profil och investeringsalternativ för att sedan plottas och analyseras per ursprunglig fastighet. Resultaten visade att båda konfigurationerna kan uppvisa lönsamhet, men endast under särskilda förutsättningar. Den enskilda fasbalanseraren bedömdes som lönsam för fastigheter vars strömtoppar är påtagligt obalanserade och som överstiger 50 A, med största möjliga lönsamhet för profiler som överstiger 63 A då dessa möjliggör ett tariffbyte. Det kombinerade systemets lönsamhet bedömdes vara ännu mer beroende av tariffbytet och därför endast lönsamt för strömtoppar över 63 A. En betydligt större grundinvestering för det kombinerade systemet gör vidare att den enskilda fasbalanseraren i regel är att föredra, såvida inte kalkylräntan är så låg som 2 % eller mindre. Baserat på detta uppmanas potentiella investerare att undersöka balanstillståndet hos deras laster och att utföra en egen kalkyl baserat på deras specifika last, kapitalkostnad och nätföretag.
39

Machine learning based user activity prediction for smart homes

Goutham, Mithun January 2020 (has links)
No description available.
40

An airports’ need of change to go 100% green using an energy storage system and solar power : Integration of energy storage system and photovoltaics to an existing system

Törnberg, Carl January 2022 (has links)
This thesis explores what Karlstad Airport needs to go 100% green. Photovoltaics are assumed to be installed at the facility and a Hydrogen Energy Storage System and Battery Energy Storage System will be evaluated to reduce peaks during charging of the planes. Different power peak limits are explored as well as different sized Energy Storage Systems and later evaluated economically. A method to find the cheapest possible system is created with some assumptions and is then used to evaluate throughout the whole dataset. In the end any of the different sized Energy Storage Systems reduces the profitability when considering each systems expected lifecycle.

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