Power to gas is an emerging energy storage technology with great versatility. This thesis investigates the economic prospects of investing in such a facility via a case study linked to the Söderåren biogas plant in southern Sweden.The basis for this study is cash flow scenario analysis based on revenues and costs, which are referred as scenario parameters. Each of these parameters have different options to choose from, with nominal values chosen as the most likely options for each scenario parameter. In current market condition it was observed that installing power to gas is not profitable. However after exploring numerous combinations of scenarios, it was found that the electrical grid fee charges and higher ancillary service income was critical to achieve a viable business case for power to gas. Another scenario achieved profitability with a small margin which occurred when the grid fee was removed, referred as “grid fee off”. Both the most likely scenario and grid fee off scenario included sensitivity analysis. This was used to observe the impact of net present value when changing one parameter at a time. / Power to gas/ El till gas är en teknik på frammarsch med mångsidiga egenskaper. Den här master uppsatsen ämnar att undersöka om power to gas är lönsamt att investera idag vid en anläggning i södra Sverige vid namn Söderåsen/Wrams biogasanläggning. Samt överskåda under vilka ekonomiska den skulle kunna bli lönsam. Resultaten kan extrapoleras till liknande biogasanläggningar med liknande ekonomiska förutsättningar.Grunden för denna studie är analys av kassaflödesscenarion baserat på intäkter och kostnader, vilket kommer att refereras till som scenarioparametrar. Var och en av dessa parametrar har olika alternativ att välja mellan, där en av dessa parametrar antas vara det mest troliga alternativet att hända verkligheten. I nuvarande marknadsförhållanden observerades det att installation av el till gas inte är lönsam. Däremot efter att ha undersökt en mängd olika scenario, tillsammans 90 stycken kombinationer av scenarier (mer finns i bilagan), visade det sig att nätavgiften var avgörande för att uppnå en bärkraftig affärssituation för el till gas. Ett alternativt scenario med slopad nätavgift illustreras därefter. Känslighetsanalys sker i det mest troliga scenariot och i det alternativa scenariot utav projektets nuvärde för belysa ändring av enskilda scenario parametrars inverkan på resultatet.En intressant men osäker ekonomisk möjlighet diskuteras kring möjligheterna att ersätta uppgraderingsenheten för konventionella biogasenheter helt och hållet. Det diskuteras hur vissa parametrar korrelerar samt ifall det går att ekonomiskt motivera an slopning av nätavgiften.Slutligen tas rekommendationer till framtida studier upp.

According to the “Draft development plan for meeting the current and future electricity demandfor 2023-2032” developed by the Polish Transmission System Operator PSE, the most appropriate solution is to significantly expand the possibilities of energy storage, due to its role as a factor improving the power balancing with the increase of wind farms and photovoltaic (PV) sources. Poland has changed the rules governing the energy industry to encourage energy storage. Few barriers have already been eliminated like double charging of transmission fees, but there is still a big novelty to come and that is the reform of the balancing market. With the introduction of this change many more revenue streams should be available that are already present in other EU countries. The objective of this thesis is to provide a high-level overview of the Polish electricity market, identification of existing legal barriers, assessing the role of battery energy storage systems (BESSs) participating in distinct applications, and evaluating a possible business case considering a foreseeable market evolution. The scope of the study is limited to only one storage option Li-Ion standalone project of 10MW/40MWh at HV Point of Connection. In literature review, there does not seem to be a study on storage in the context of Poland. Hence, identifying the research gaps, an analysis of standalone storage system for grid applications in Poland is performed. In this study the NPV, IRR and PP for different scenarios of available revenue streams is determined to compare current and future business models for techno-economic feasibility for BESS in the context of Poland. Results of the study are as following. In the future scenario under the assumed dispatch strategy and participation in CM, FCR, aFRR availability markets as well as aFRR energy market and wholesale arbitrage, the overall project IRR is around 18% with a payback time of around 5 years. Provided the number of new accessible revenue streams BESS can present a strong business case in Poland.

Today’s society already requires a great connectivity network. This need will only increase in the future, and EDGE data centres are concepts meeting this future need, where the computational power is deployed close to the end user. They are defined, in this thesis, as a concept including different nodes, or data centres, located in proximity connected and participating in the market as one entity. The electricity grid in the Nordics is also a complex system. Many types of interactions with the grid exist and depend on the type of stakeholder. One collection of such interactions is ancillary services, which refer to different types of measures that maintain a reliable grid and electricity system. Electricity consumers within the grid network have the potential to interact and participate in these different functions. In this thesis, the participation of data centres, or EDGE data centres in ancillary services market, is studied. This thesis modelled different scenarios of an EDGE data centre with the grid network. Scenario 1 looked into self-consumption; scenario 2 looked into spot trading; scenario 3 looked into the FCR-N market; scenario 4 looked into the FCR-D markets; and scenario 5 looked into the combination of self-consumption and the FCR-D markets. It is observed from the results that scenario 4 generated the most favourable economic benefits. The results in relation to the price areas (zones in Sweden) were varied for the results. The price area SE4 gave better results for scenarios 1, 2, and 5 as compared to others. The best price area for scenarios 3 and 4 was from the SE1 zone. It is observed from the results that the potential benefit of the different ancillary markets exist and are at times favourable. Hence, there lies a future potential for the participation of EDGE networks in the electricity market thereby generating benefits for the data centres as well as stability for the grid. / Dagens samhälle kräver redan ett bra nätverk för uppkoppling. Detta behov kommer bara att öka i framtiden, och EDGE:s datacenter är koncept som uppfyller detta framtida behov, där datakraften placeras nära slutanvändaren. De definieras i denna avhandling som ett koncept som omfattar olika noder, eller servrar, som är placerade i närheten av varandra och som deltar på marknaden som en enhet. Elnätet i Norden är också ett komplext system. Det finns många olika typer av interaktioner med elnätet som beror på vilken typ av aktör det är fråga om. En samling av sådana interaktioner är stödtjänster, som avser olika typer av åtgärder som upprätthåller ett tillförlitligt nät och elsystem. Elkonsumenter inom elnätet har möjlighet att interagera och delta i dessa olika funktioner. I den här avhandlingen undersöks datacentraler, eller EDGE-datacenter, som deltar. I denna avhandling har olika scenarier för EDGE-datacenter modellerats i förhållande till elnätet. I scenario 1 undersöktes självkonsumtion, i scenario 2 spothandel, i scenario 3 FCR-N-marknaden, i scenario 4 FCR-D-marknader och i scenario 5 en kombination av självkonsumtion och FCR-D-marknader. I korthet gav scenario 4 de mest gynnsamma ekonomiska fördelarna. De potentiella miljöfördelarna diskuteras och kan inte lika lätt kvantifieras. Resultaten i förhållande till prisområdena varierade för resultaten. Prisområde SE4 gav de bästa resultaten för scenario 1 och 2 samt 5. Det bästa prisområdet för scenario 3 och 4 var SE1. Det framgår tydligt av denna avhandling att de potentiella fördelarna med de olika stödmarknaderna finns och att de vid vissa tillfällen är mycket gynnsamma med tanke på de höga lagringskostnaderna. EDGE-nätverkens framtida potentiella deltagande ger positiva resultat i både ekonomiska och miljömässiga termer.

This thesis investigates the opportunities and challenges of using repurposed electric car batteries, so called Second-life Battery (SlB), in a residential building as an energy storage. The performance of SlBs is compared to a First-life Battery (FlB) by identifying two potential scenarios and using a battery degradation model. The first scenario involved the batteries providing ancillary services to the grid, while in the second scenario the batteries were used for peak shaving. The battery degradation model is based on typical usage from the scenarios. The thesis findings indicate that the SlB degrades at a slower rate than the FlB, but can perform fewer cycles. Economic performance varies based on the application and initial assumptions. Both batteries proved to be profitable in the two scenarios studied, with some of the SlB configurations outperforming FlB configurations and vice versa. The yearly compensation received, when providing ancillary services with a 1000 kWh battery, ranged between 3-8 MSEK, while the yearly compensation received, when peak shaving with a 200-300 kWh battery, ranged between 20-35 thousand SEK. The main challenges identified included reduced lifespan, security risks, potential price increases, and space constraints. On the other hand, the main opportunities identified included potential price decreases and sustainability benefits such as carbon footprint reduction and grid stability. These results may provide valuable insights for informed decision-making regarding investments in FlBs and SlBs on the Swedish market.

[pt] No atual modelo econômico do setor elétrico, é necessário identificar os agentes beneficiados pelos serviços ancilares à transmissão de potência de forma a alocar adequadamente os custos de investimento, de operação e manutenção do equipamento necessário para a prestação do serviço. Entre os serviços ancilares, destaca-se o suporte de potência reativa para a regulação de tensão. Este trabalho apresenta um método baseado nos multiplicadores de Lagrange de um problema de otimização associado ao cálculo das medidas corretivas necessárias para lidar com níveis de tensão inadequados. Dois critérios de otimização são definidos: mínimo corte de carga e mínima alocação de potência reativa. Os multiplicadores de Lagrange definem a responsabilidade de cada barra quando ocorrem violações de tensão no sistema. O método permite não só identificar as barras beneficiadas pelo equipamento de compensação de potência reativa como também alocar os custos entre elas. É priorizada a confiabilidade do sistema, analisando as contingências possíveis e considerando suas respectivas probabilidades de ocorrência. O programa computacional NH2, desenvolvido pelo CEPEL, é a ferramenta básica para o desenvolvimento deste trabalho. O método é aplicado, a título de ilustração, ao sistema IEEE - RTS de 24 barras e ao sistema da Área Rio. Os resultados obtidos são comparados com um método já existente, que define fatores de alocação de custos medindo os benefícios às barras devido ao suporte de potência reativa. Esta comparação, benefício x responsabilidade, e a própria teoria dos dois métodos, mostram que o método proposto identifica mais adequadamente as barras e os respectivos fatores para a repartição dos custos. / [en] It is important to identify the agents that take advantage of the ancillary services for system operation in the nowadays electricity market. The actual economic design requires that the costs of investment, operation and maintenance of the necessary equipment should be properly allocated between these agents. Among the ancillary services, the reactive power support for voltage regulation is quite important. It is presented a method that identifies the buses that take advantage of the reactive power equipment and allocates the costs between each one of them. The power system reliability is taken into account. The analysis considers possible contingencies and their respective probability of occurrence. The computer program NH2, developed by CEPEL, is the main tool for the development of this work. The method is based on the Lagrangian multipliers of an optimal power flow problem (OPF) associated to corrective measures necessary to deal with voltage violations. Two different objective functions are used: minimum load shedding and minimum reactive power injection. The Lagrangian multipliers define the responsibility of each bus when system voltage violations occur. For the purpose of illustration, the method is applied on the 24 bus IEEE Reliability Test System and on Área Rio system. Results are compared with those produced by other existing method that defines cost allocation factors measuring the benefit due the reactive support. This comparison, benefit x responsibility, and the theory used by both methods, show that the proposed method identifies more appropriately the buses and the corresponding factors to allocate the costs.

[pt] Com a implantação do novo modelo econômico nos sistemas de potência, a justa remuneração das empresas provedoras de serviços ancilares tem se tornado um assunto grande importância. O suporte de potência reativa, por se tratar também de um serviço ancilar, está inserido neste contexto. Desta forma, a factível identificação dos agentes beneficiários pelo suporte, bem como as proporções deste beneficiamento podem implicar em um mecanismo viável de remuneração para os custos de cada fonte provedora. Este trabalho apresenta um método de alocação de custos pelo suporte de potência reativa baseado nos princípios fundamentais da teoria de circuitos elétricos, buscando determinar a contribuição de potência reativa de cada fonte para cada barra de carga. Para isto, é sugerida uma modelagem de fontes de tensão, que permite levar em conta a natureza local da relação Q-V, proporcionando uma abordagem simples e clara do problema. Complementarmente é apresentado um método de alocação das perdas reativas em cada ramo de transmissão entre as fontes provedoras de potência reativa. Para validar o método proposto, são realizados testes em sistemas de potência de pequeno e médio porte, apresentado as parcelas de contribuição de cada fonte de potência reativa para cada carga, e adicionalmente para as perdas reativas em cada ramo de transmissão. Comparações são estabelecidas com um método existente, onde é constatado que o método proposto apresenta maior coerência com as propriedades elétricas dos sistemas de potência, destacando-se a verificação clara da natureza local do consumo de potência reativa. Em relação aos resultados da alocação de perdas reativas, verifica-se que o método serve como indicativo sobre o uso da rede de transmissão por parte de cada fonte de potência reativa. / [en] After implantation of power systems` new economic model, a fair remuneration strategy of ancillary services suppliers had became an important issue. Reactive power support is also an ancillary service, thus, it belongs to this context. Then, identification of service beneficiaries as well as the benefit proportions may take a feasible remuneration mechanism for each source. This work presents a reactive power support cost allocation method based on fundamental principles of circuit theory, where reactive power contribution from each source to each load is calculated. This method suggests a modeling of voltage sources, which takes into account the Q-V relationship, providing a simple and clear treatment of the problem. Additionally, a reactive loss allocation method to each branch is presented. To validate the proposed method, tests with small and medium size systems are realized. So, there are presented results of reactive power demand and transmission losses allocation into systems` sources. Comparisons with an existent method are established, when we can verify that the proposed method brings more coherence with the electrical properties of power systems and the local nature of reactive power consumption. In the other hand, results of reactive losses allocation can indicate the transmission network usage by each reactive power source.

Le sujet s'inscrit dans la stratégie d'augmentation de la pénétration des énergies renouvelables dans les réseaux électriques, en particulier ceux qui sont faiblement interconnectés, tels que les réseaux électriques insulaires. Une limite de pénétration des énergies intermittentes de 30% en puissance instantanée dans ces réseaux a été fixée par la loi française. Pour permettre de dépasser cette limite, une solution est de coupler les sources de production décentralisée et intermittente avec du stockage.Dans cette thèse, nous nous sommes intéressés au volant d’inertie, système de stockage permettant de convertir l’énergie électrique sous forme cinétique et vice versa. Celui-ci a en effet un nombre de cycles charge/décharge important en comparaison avec une batterie électrochimique et peut être utilisé pour lisser la production photovoltaïque. La fluctuation de l’énergie photovoltaïque est en effet faiblement prédictible au cours du temps et elle ne peut pas être contrôlée, notamment sa chute de production. La production photovoltaïque peut chuter jusqu’à 80 % de la puissance maximale en 30 secondes, et déstabiliser ainsi le réseau électrique. Le réseau électrique insulaire, tel que celui de la Corse, n’est pas interconnecté au réseau électrique continental. Les réseaux non – interconnectés sont plus fragiles et moins stables. Ainsi, le développement massif des centrales photovoltaïques peut faire fluctuer la fréquence et la tension du réseau. Le volant d’inertie a l’avantage de posséder un faible temps de réponse (quelques centaines de millisecondes). Cependant, il a une capacité énergétique moindre. Nous allons donc exploiter les avantages du volant d’inertie en le gérant en temps réel avec un calculateur approprié. Un volant d’inertie d’une puissance de 15 kVA et d’une capacité énergétique de 112 Wh a été caractérisé et testé à l’INES Chambéry en utilisant un simulateur réseau temps réel (RTLab®), un calculateur temps réel dSPACE® et une centrale PV. Le système de stockage est composé d’une machine électrique asynchrone et d’un volant d’inertie cylindrique en acier. Le logiciel Matlab/Simulink® est utilisé pour implémenter les lois de commande nécessaires à son pilotage. Dans cette thèse, le banc de test est présenté ainsi que les résultats sur les services système (lissage de puissance, régulation de la fréquence et de la tension). Trois méthodes de lissage de puissance sont présentées et évaluées (lissage avec une fonction de transfert, lissage avec limiteur de pente et lissage n’utilisant pas aucune fonction de lissage). La troisième méthode n’utilisant ni une fonction de transfert, ni une fonction limitant la pente des variations, nécessite moins de paramètres et s’avère plus optimale et plus robuste. Un volant d’inertie avec une autre technologie de machine électrique (la machine à réluctance variable) a été également caractérisé. C’est une Alimentation Sans Interruption (ASI), sur laquelle des paramètres tels que l’autodécharge et les rendements du système (en charge, en décharge et au repos) ont pu être mesurés. / The subject is part of the strategy to increase the penetration of renewable energy in power systems, particularly those that are poorly interconnected, such as island grids. A limit of penetration of intermittent energy by 30% in instantaneous power in these electrical grids was set by a French law. To help overcome this limitation, a solution is to couple the sources of decentralized and intermittent generation with energy storage systems. In this thesis, we are interested in flywheel energy storage systems (FESS) that converts electrical energy in kinetic energy form and vice versa. FESS have a number of cycles charge / discharge large compared with electrochemical batteries and can be used to smooth the photovoltaic power generation. The fluctuation of photovoltaic instantaneous power is indeed weakly predictable over time and it cannot be controlled, including its production fall. PV production can decrease up to 80% of its maximum power in 30 seconds, and so destabilize the grid. The island grids, such as that of Corsica, are not interconnected to the mainland power grid. The non - interconnected grids are more fragile and less stable. Thus, the massive development of photovoltaic power plants can cause fluctuations in the frequency and voltage. The flywheel has the advantage of having a low response time (a few hundred milliseconds). However, it has a lower energy capacity. The benefits of FESS are used by managing it in real time with an appropriate computer. A flywheel with a power of 15 kVA and an energy capacity of 112 Wh was characterized and tested at INES Chambery using a real time grid simulator (RTLab®), a real-time computer (dSPACE®) and a PV power plant. The storage system is composed by an asynchronous electrical machine and a cylindrical steel flywheel. The Matlab Simulink / software is used to implement the control laws necessary for its control. In this thesis, the test bench is presented and the results of ancillary services (power smoothing, frequency and voltage regulation). Three power smoothing methods are discussed and evaluated (smoothing with a transfer function, with a slope limiter function and a method not using any smoothing function). The third method uses neither a transfer function, nor a function that limits the slope variations, requires fewer parameters, and is more optimal and more robust. A flywheel with another electrical machine technology (the switched reluctance machine) has also been characterized. This is an Uninterruptible Power Supply (UPS) on which parameters such as self-discharge and efficiencies (charging mode, discharging mode and standby mode) were measured.

<p><strong>Bakgrund/problem: </strong>Fastighetsmäklare ersätts idag främst genom provision för sitt huvuduppdrag fastighetsförmedling. Ett lagförslag vill tillåta ersättning för förmedling av sidotjänster som exempelvis bolån. Risken med lagförslaget är att mäklarens roll som oberoende mellanman försvinner om ersättningen för sidotjänstförmedling är uteslutande provisionsbaserad. Ledningen måste därför utforma välfungerande styrsystem för att undvika negativa effekter.</p><p><strong>Syfte:</strong> Att utforma ett förslag till hur företag kan undvika negativa effekter vid provisionsbaserad ersättning för sidotjänster.</p><p><strong>Metod:</strong> En kvalitativ fallstudie har genomförts med individuella, semistrukturerade intervjuer, enkätundersökning samt sekundärkällor.</p><p><strong>Resultat:</strong> Företagsledningen bör använda sig av ett kombinerat ersättningssystem med både fast och rörlig lön för sidotjänstförmedling. Vidare bör även hänsyn tas till åtgärder inom beteendestyrning, såsom utformning av välfungerande processer för de anställdas arbetssätt, samt inom social styrning, såsom utbildning av de anställda.</p> / <p><strong>Background: </strong>Real Estate Agents are today mainly compensated through commission for their main task; to mediate in Real Estate sales. There is a legislative proposal to authorize compensation for the disclosure of ancillary services such as mortgages. The risk with the proposal is that the Real Estate Agent’s role as an independent intermediate may disappear if the compensation for the disclosure of ancillary services is entirely commission based. Management must therefore develop effective control system to avoid adverse effects.</p><p><strong>Purpose:</strong> To develop a proposal for how companies can avoid adverse effects on a commission based compensation for ancillary services.</p><p><strong>Methodology:</strong> A qualitative case study has been carried out with individual, semi-structured interviews, a questionnaire survey and secondary sources.</p><p><strong>Result:</strong> The management should make use of a combined compensation of both fixed and variable pay for ancillary service brokerage. Furthermore, it should also take into account the measures in behavioral control, such as the design of efficient working processes, and social control, such as employee training.Key</p>

Recently, the widespread use of power system controllers, such as PSS and FACTS controllers, has led to the analysis of their effect on the overall stability of power systems. Many studies have been conducted to allocate FACTS controllers so that they achieve optimal power flow conditions in the context of Optimal Power Flow (OPF) analysis. However, these studies usually do not examine the effect of these controllers on the voltage and angle stability of the entire system, considering that the types of these controllers and their control signals, such as reactive power, current, or voltage, have significant effect on the entire system stability. <br /><br /> Due to the recent transition from government controlled to deregulated electricity markets, the relationship between power system controllers and electricity markets has added a new dimension, as the effect of these controllers on the overall power system stability has to be seen from an economic point of view. Studying the effect of adding and tuning these controllers on the pricing of electricity within the context of electricity markets is a significant and novel research area. Specifically, the link among stability, FACTS controllers and electricity pricing should be appropriately studied and modelled. <br /><br /> Consequently, in this thesis, the focus is on proposing and describing of a novel OPF technique which includes a new stability constraint. This technique is compared with respect to existent OPF techniques, demonstrating that it provides an appropriate modelling of system controllers, and thus a better understanding of their effects on system stability and energy pricing. The proposed OPF technique offers a new methodology for pricing the dynamic services provided by the system's controllers. Moreover, the new OPF technique can be used to develop a novel tuning methodology for PSS and FACTS controllers to optimize power dispatch and price levels, as guaranteeing an adequate level of system security. All tests and comparisons are illustrated using 3-bus and 14-bus benchmark systems.

Recently, the widespread use of power system controllers, such as PSS and FACTS controllers, has led to the analysis of their effect on the overall stability of power systems. Many studies have been conducted to allocate FACTS controllers so that they achieve optimal power flow conditions in the context of Optimal Power Flow (OPF) analysis. However, these studies usually do not examine the effect of these controllers on the voltage and angle stability of the entire system, considering that the types of these controllers and their control signals, such as reactive power, current, or voltage, have significant effect on the entire system stability. <br /><br /> Due to the recent transition from government controlled to deregulated electricity markets, the relationship between power system controllers and electricity markets has added a new dimension, as the effect of these controllers on the overall power system stability has to be seen from an economic point of view. Studying the effect of adding and tuning these controllers on the pricing of electricity within the context of electricity markets is a significant and novel research area. Specifically, the link among stability, FACTS controllers and electricity pricing should be appropriately studied and modelled. <br /><br /> Consequently, in this thesis, the focus is on proposing and describing of a novel OPF technique which includes a new stability constraint. This technique is compared with respect to existent OPF techniques, demonstrating that it provides an appropriate modelling of system controllers, and thus a better understanding of their effects on system stability and energy pricing. The proposed OPF technique offers a new methodology for pricing the dynamic services provided by the system's controllers. Moreover, the new OPF technique can be used to develop a novel tuning methodology for PSS and FACTS controllers to optimize power dispatch and price levels, as guaranteeing an adequate level of system security. All tests and comparisons are illustrated using 3-bus and 14-bus benchmark systems.