New ideas and solutions are necessary to face challenges in the electricity industry. The application of electricity storage systems (ESS) can improve the quality and stability of the existing electricity network. ESS can be used for peak shaving, instead of installing new generation or transmission units, renewable energy time-shift and many other services. There are few ESS technologies existing today: mechanical, electrical and electrochemical storage systems. Flow batteries are electrochemical storage systems which use electrolyte that is stored in a tank separated from the battery cell. Electrochemistry is very important to understand how a flow battery functions and how it stores electric energy. The functioning of a flow battery is based on reduction and oxidation reactions in the cell. To estimate the voltage of a cell the Nernst equation is used. It tells how the half-cell potential changes depending on the change of concentration of a substance involved in an oxidation or reduction reaction. The first flow battery was invented in the 1880’s, but was forgotten for a long time. Further development was revived in the 1950’s and 1970’s. A flow battery consists of two parallel electrodes separated by an ion exchange membrane, forming two half-cells. The electro-active materials are stored externally in an electrolyte and are introduced into the device only during operation. The vanadium redox battery (VRB) is based on the four possible oxidation states of vanadium and has a standard potential of 1.23 V. Full ionic equations of the VRB include protons, sulfuric acid and the corresponding salts. The capital cost of a VRB is approximately 426 $/kW and 100 $/kWh. Other flow batteries are polysulfide-bromine, zinc bromine, vanadium-bromine, iron-chromium, zinc-cerium, uranium, neptunium and soluble lead-acid redox flow batteries. Flow batteries have long cycle life and quick response times, but are complicated in comparison with other batteries. / Nya idéer och lösningar är nödvändiga för att möta utmaningarna i elbranschen. Användningen av elektriskt lagringssystem (ESS) kan förbättra kvalitén och stabiliteten av det nuvarande elnätet. ESS kan användas till toppbelastningsutjämning, istället för att installera nya produktions eller kraft överförnings enheter, förnybar energi tidsförskjutning och många andra tjänster. I dagsläget finns det få olika ESS: Mekaniska, elektriska och elektrokemiska lagringssystem. Flödesbatterier tillhör kategorin elektrokemiska lagringssystem som använder sig utav elektrolyt som är lagrad i en tank separerad från battericellen. För att kunna förstå hur flödesbatteriernas funktioner och på vilket sätt som dem lagrar elektriskt energi är det viktigt att kunna elektrokemi. Flödesbatteriernas funktion är baserad på reduktions och oxidations reaktioner i cellen. Nernsts ekvation används för att kunna uppskatta voltantalet i en cell. Nernsts ekvation säger hur halvcell potentialen ändras beroende av ändringen av koncentrationen av ämnet involverat i oxidations eller reduktions reaktionen. Det första flödesbatteriet uppfanns 1880-talet, men blev bortglömt under en lång tid. Vidare utveckling förnyades under 1950 och 1970-talet. Ett flödesbatteri består utav två parallella elektroder som är separerade utav ett jonbytes membran vilket formar två halvceller. Dem elektroaktiva materialen är lagrade externt i elektrolyt och är införs bara i anordningen under användning. Vanadium redox batteriet (VRB) är baserat på dem fyra möjliga oxidations tillstånden av vanadium och har en standard potential på 1.23 V. Fullt joniska ekvationer av VRB inkluderar protoner, svavelsyra och deras motsvarande salter. Kapitalkostnaden av ett VRB är ungefär 426 $/kW och 100 $/kWh. Det finna andra flödesbatterier som är polysulfide-brom, zink-brom, vanadium-brom, järn-krom, uran, neptunium och löslig blysyre redox flödesbatterier. Flödesbatterier har en lång omloppstid samt en snabb svarstid men är komplicerade jämfört med andra batterier.

Under 2011 började MacBat AB ta fram ett elenergilager kallat Macbat Energy Storage System (MESS), vilket är uppbyggt av 360 stycken tvåvolts bly-syrabatterier inhysta i ett 20 fots container. Då bly-syrabatterier är känsliga för värme är den här studien inriktad på att utreda hur stort kylbehovet blir under olika förutsättningar där kyldistribution, drifttemperatur på batterierna, klimat, isolering och termiska tröghet är varierande parameterar. Det ska även avgöras vilken konfiguration av kyldistribution och isolering som ger lägst kylbehov för de studerade klimaten, vilka är av varmtempererad, arid och tropisk karaktär. För att besvara studiens två mål togs fyra matematiska modeller fram i SIMULINK. Två luftkylda och två vattenkylda där en av varje var isolerad med 100 mm mineralull medan den andra var oisolerad. För samtliga modeller varierades drifttemperaturen mellan 25 – 35 °C och de studerade klimaten utgjordes av Phnom Phen, Kambodja, Djibouti, Djibouti, Bagdad, Irak samt London, England. För de vattenkylda modellerna varierades även MESS termiska tröghet i spannet 1,8058 – 9,0288 MJ/K genom att öka mängden kylvatten i systemet som användes för att kyla batterierna. Batteriernas drifttemperatur visade sig vara den parameter som i högst grad avgör kylbehovets storlek. Isoleringen gav en reducerande effekt på kylbehovet i de fall då omgivningstemperaturen under längre perioder överstiger batteriernas drifttemperatur. Varierande termisk tröghet, i de vattenkylda modellerna, hade liten eller ingen inverkan på kylbehovet. Det beror förmodligen på att den termiska massa som konstant finns i batterierna i form av elektrolyt var betydligt större. I fråga om vilken konfiguration av distributionssystem och isolering som ska användas för att erhålla ett lågt kylbehov visade sig detta bero på klimatet och drifttemperaturen på batterierna. Varmtemperade klimat som London behöver dock inget kylsystem överhuvudtaget. / In 2011 MacBat AB began to develop a electrical energy storage system called Macbat Energy Storage System (MESS), which is made up of 360 two volt lead acid batteries housed in a 20 foot container. However, while lead acid batteries are sensitive to heat this study is focused on investigating how great a cooling demand will be required under different conditions in which chilled distribution, operating temperature of the batteries, climate, insulation and thermal inertia are varied parameters. The study will also determine the configuration of chilled distribution and isolation that gives minimum cooling requirements for the studied climates, which is warm temperate, arid and tropical nature To answer the study's two goals four mathematical models were developed in SIMULINK. Two air-cooled and two water-cooled where one of each was insulated with 100 mm mineral wool while the other was bare. For all models the operating temperature varied between 25 - 35 ° C and the studied climates consisted of Phnom Penh, Cambodia, Djibouti, Djibouti, Baghdad, Iraq, and London, England. For the water cooled models thermal inertia was also varied in the range of 1.8058 to 9.0288 MJ/ K by increasing the amount of cooling water in the system used to cool the batteries. The battery operating temperature was proven to have the most significant impact on the cooling load. The isolation yielded a reducing effect on the cooling load in the case where the ambient temperature surpassed the battery operating temperature during longer periods. Varying thermal inertia of the water cooled models had little or no impact on the cooling load. It is probably due to the electrolyte in the batteries. It is a considerably larger source of thermal mass and is constant in all the models. Which configuration, regarding the distribution system and insulation, that obtains a low cooling requirement was found to depend on the ambient climate and the battery operating temperature. However, warm temperate climates such as London requires no cooling system at all.

This study investigates the potential of installing an integrated solar powered Organic Rankine Cycle (ORC) with electric energy storage (EES) to provide clean energy to commercial buildings in different climate zones in the US. Reducing the primary energy consumption (PEC), lowering the carbon dioxide emissions (CDE) and increasing the operational cost savings are primary objectives. Firstly, a large office building for eight US climates is studied. The EES is sized to store all the electricity generated by the system. Secondly, the system is studied for sixteen different commercial buildings, in the best climate zone, by considering two operational strategies. Finally, the influence of variable expander efficiency on the system performance is investigated. Results indicate that Phoenix is the best location in the US, among the evaluated locations, to install the ORC-EES. The model for the full-service restaurant shows higher savings and more electricity supply percentage than the other buildings. The model under the variable expander efficiency lowers the yearly PEC by 1.6% and CDE and operational cost savings both by 11%.

Les défis auxquels les systèmes électriques font face actuellement (intégration massive des énergies renouvelables, développement de la production distribuée, réduction des émissions CO2, etc.) donnent lieu à une intuition partagée sur la croissance des besoins en stockage d’électricité. Néanmoins, les investissements en stockage engagés par des acteurs individuels restent à ce jour très faibles, sauf pour la technologie de stockage par pompage-turbinage. Ceci s’explique potentiellement par le fait que l’usage du stockage par un seul acteur ne permet que rarement de recouvrir le coût d’investissement du stockage. En tant qu’actif multifonctionnel, le stockage est capable de fournir de nombreux services à différents acteurs. La façon dont le stockage est utilisé devrait être adaptée afin de permettre une mutualisation du coût d’investissement et des bénéfices parmi différents acteurs dans le paysage dérégulé des systèmes électriques en Europe.La thèse a permis d’étudier les mécanismes efficaces permettant 1) aux acteurs régulés et dérégulés de partager l’utilisation d’une unité du stockage, et 2) à une coordination efficace des utilisations décentralisées du stockage. A cet effet, nous proposons un design de marché qui permet d’agréger les valeurs du stockage en deux dimensions.Premièrement, des valeurs peuvent être agrégées sur plusieurs horizons temporels. Les acteurs peuvent avoir intérêt à décider l’utilisation du stockage à différents moments avant la livraison en temps réel. L’agrégation verticale est obtenue par la superposition des profils d’utilisation décidés à différents horizons temporels. Deuxièmement, les valeurs peuvent être agrégées parmi différents acteurs. Ceci consiste à coupler le stockage avec des marchés organisés de l’électricité. A un horizon donné, l’opérateur du stockage communique ses capacités disponibles à l’opérateur du marché, qui vaviincorporer ces capacités dans le processus de clearing de marché afin de maximiser le bien-être social.La thèse démontre qu’il est possible de faire partager une unité du stockage par des acteurs régulés et dérégulés d’une manière systématique. Des simulations montrent que l’agrégation des valeurs du stockage, de la façon proposé dans la thèse, peut conduire à une augmentation évidente de la rentabilité du stockage. Elles montrent aussi qu’après la clôture de toutes les activités commerciales à un horizon donné, il reste systématiquement des capacités du stockage non-utilisées, qui sont difficilement valorisables par les acteurs dérégulés, mais pourraient être servies par les acteurs régulés. Le mécanisme d’agrégation permet de capturer la valeur de ces capacités, tout en respectant le principe d’ « unbundling » du secteur électrique européen. / The challenges faced by the power systems nowadays (massive integration of intermittent energy sources, development of distributed generation, reduction of CO2 emissions, etc.) give rise to a widespread notion on the growing needs for electric energy storage (EES). In spite of this, little investment on EES, however, has been carried out by individual actors. An exception concerns pumped hydro storage technology, but the development of this technology is highly constrained by the existence of suitable sites in Europe. The lack of investments in EES, despite its general usefulness, is potentially due to the fact that the usage of storage by one individual actor generally could not allow him to recover the high investment costs involved. As a multi-functional asset, EES can provide numerous benefits to different actors. A potential means to promote EES may involve socialising the investment cost and benefits of EES among different actors in the deregulated power systems in Europe.This thesis studies how to create efficient mechanisms to allow 1) all the actors, both regulated and deregulated, to share the use of an EES unit, and 2) an effective coordination on the decentralized usages of storage by different actors. To this aim, we propose a market design that enables the aggregation of the values of EES along two dimensions, namely vertical and horizontal aggregation.Firstly, the values can be aggregated vertically upon several time horizons. Actors may have different needs for EES at different time horizons. The vertical aggregation is achieved by superposing utilisation profiles of EES decided at different moments in time. The compatibility of the different utilisation profiles is ensured by a coordination mechanism. Secondly, the values can also be aggregated horizontally among a large number of actors. The horizontal aggregation consists in coupling EES to the electricityivmarkets. At a given time horizon, the storage operator communicates the available capacities of EES to the market operator, who will incorporate these capacities in the market clearing process to maximise the social welfare.The thesis proves that it is possible for different actors, both regulated and deregulated, to share the use of storage in a systematic way. The simulation results show that the aggregation of values of EES, in the way proposed by the thesis, can lead to higher return on investment. The simulation also show that, after the closure of all commercial activities (at certain time horizon), there are systematically residual capacities of EES which are difficult to be valued by deregulated actors, but can be used by regulated actors. The value of these capacities can be effectively captured in the proposed aggregation mechanism, while respecting the unbundling principle of the European electricity sector.

This master thesis summarizes history of electric vehicles from its inception to present. Vehicles are divided into three groups according to the type of drive, special attention is paid to electric vehicles. Furthermore, typical ways of electric energy storage are presented, especially in the form of electrochemical cells, which are used in electric vehicles. The thesis also describes the situation of electromobility in the Czech Republic, namely government support, distribution companies tariffs, charging infrastructure and available electric vehicles. Finally, the concept of connecting electric vehicles to renewable energy source is described, with financial calculations for three profiled drivers.

Doctoral thesis deals with domain of electric energy storage. It seeks to define the methods of accumulation, which can be used in industrial applications and define the conditions for the use of storage systems in electric power systems with extended penetration of renewable energy sources. In the context of current developments in this field is analyzed detail one of the perspective storage systems - Vanadium Redox Battery (VRB). One of the outcomes of this work is economic and energy analysis of storage systems, which are conceived with a disproportion between production and consumption of energy. The work was supported by the Centre for Research and Utilization of Renewable Energy (CVVOZE) no. CZ.1.05/2.1.00/01.0014 and research project no. FEKT S-11-9.

The thesis deals with the use of solar energy for electromobility. First, the potential of electromobility on the current market is theoretically discussed. This issue includes mainly the producers of electrically powered vehicles, the issue of electric energy storage and the real applications of fast charging and photovoltaic charging stations. In the next part, electric cars are analyzed, which use solar energy for their function and their efficiency is compared with the effiency of combustion engines. The main part of this thesis is the design of photovoltaic charging station for electric vehicles. The final part deals with the economic evaluation of the proposed charging station.

The thesis deals with the use of solar energy for electromobility. First, the potential of electromobility on the current market is theoretically discussed. This issue includes mainly the producers of electrically powered vehicles, the issue of electric energy storage and the real applications of fast charging and photovoltaic charging stations. The second part of the diploma thesis deals with the measurement of electric car consumption and the evaluation of measurement results. In the next part, electric cars are analyzed, which use solar energy for their function and their efficiency is compared with the effiency of combustion engines. The main part of this thesis is the design of photovoltaic charging station for electric vehicles. The final part deals with the economic evaluation of the proposed charging station.