In this thesis the potential benefits of combining a photovoltaic (PV) system with a battery storage are investigated. The thesis is conducted at the company WSP in Uppsala and the aim is to design a PV system for the new city bus depot that is planned to be built in Uppsala, estimate the PV system capacity and investigate whether a battery storage can increase the self-consumption of the system. The results of this study are that the most appropriate installation of the PV modules is to place them horizontally on the roof and by that one can achieve an installed power of 715 kWp and a total annual electricity production of 871 MWh. This corresponds to a self-sufficiency of 29 % and a self-consumption of 92 %, which indicate that overproduction of electricity sometimes occurs. How different battery storages, based on both lead-acid and lithium-ion batteries, affect the system is evaluated by developing a battery model in MATLAB. From the results of the battery model it is concluded that battery storages with a capacity of 0.3–0.8 kWh/kWp are most suitable to combine with the PV system and this applies to both lead-acid and lithium-ion batteries. The interval 0.3–0.8 kWh/kWp corresponds to battery capacities of 200–600 kWh and the self-consumption increases to 93–94 % for the lead-acid battery storages and to 93–95 % for the lithium-ion battery storages. The economic analysis show that it is generally more profitable to increase self-consumption of self-produced PV power than to sell it to the grid. However, the high costs that are associated with the battery storages eliminates the economic benefits of the increased self-consumption of PV power. Therefore, it is not considered possible to justify the installation of a battery storage at the bus depot.

Cette thèse propose principalement, un algorithme État-Flow MPPT basé P&O, amélioré avec deux degrés de liberté, dans lequel le système événementiel (MPPT) de comportement est modélisé par le décrivant en terme de transition entre les états, sous certaines conditions. Secondairement, un algorithme étendu MPPT, base d'exploitation en parallèle de l'état-débit est en outre proposé d'être une solution difficile pour le contrôle indépendant du système hybride, où la caractéristique de contrôle continu peut se présenter au cours d'un certain état de travail tout en discrète, est indiquée le long des transitions d'état. Deux configurations possibles pour le système hybride sont proposées : deux convertisseurs DC/DC séparés, et un convertisseur de sortie unique à double entrée (DISO) de configurations. Enfin, il est proposé, un comportement du système DC modélisation utilisant État-Flow, menant à l'ensemble de la conception de la stratégie de commande qui concernent RES MPPT, RES et la coordination BESS, la stabilité du système d'alimentation et de régulation de la tension du bus DC. La simulation et les résultats expérimentaux valident l'efficacité et l'applicabilité de l'algorithme proposé. Les deux résultats montrent la supériorité du MPPT basé proposé État-Flow pour réduire les oscillations de puissance RESs à l'état d'équilibre dans diverses conditions d'exploitation, en plus de son démarrage plus rapide, et l’opération de transition sans divergence de la MPP, selon des conditions météorologiques variables. / This thesis primarily proposes, an improved P&O based State-Flow MPPT algorithm featuring two degree of freedom, in which the event driven system (MPPT) behaviour is modelled by describing it in terms of transitions among states under certain conditions. Secondarily, an extended parallel operating State-Flowbased MPPT algorithm is further proposed to be a challenging solution for the independent control of the hybrid system, where continuous control characteristic can present during a certain working state while discrete one is indicated along state transitions. Two possible configurations for the hybrid system are proposed; two separate DC/DC converters and dual input single output converter (DISO) configurations. Finally it is proposed, DC system behaviour modelling using State-Flow leading to the whole control strategy design which concern RESs MPPT, RESs and BESS coordination, power system stability and DC bus voltage regulation.Simulation and experimental results validate the effectiveness and applicability of the proposed algorithm, both results show the superiority of the proposed State-Flow based MPPT in reducing the RESs power oscillations at steady-state in various operating conditions in addition to its faster start-up and transition operation without divergence from the MPP during sudden varying weather conditions.

An ever-decreasing cost of photovoltaics (PV) combined with generous installation subsidies lead to a growth of PV systems in Sweden. A large-scale penetration of PV power would make Energy Storage Systems (ESS) interesting for providing back-up storage, enabling flexibility and regulating intermittence. ESS represents a vital link between electrical supply and demand, and moreover a critical feature for increasing the use and attractiveness of renewable and intermittent energy sources. The purpose of this study is to do a quantitative analysis examining the most beneficial way to store electricity from PV regarding investment cost, life span, capacity and pay-off time. The study object is Valsätraskolan, a school in Uppsala with an existing PV system. The thesis shows that Lithium-ion batteries are the best prospected battery type but still not an economically profitable investment. With the current grid- and battery prices the most suitable battery solution has a pay-off time of 125 years. If the school would extend their PV system to cover all preferable roof areas, the pay-off time would be 48 years. If ESS are to become attractive from a financial point of view, the grid prices would have to increase and the cost for ESS decrease substantially.

The main point of this thesis is the extension of the complex solar radiation simulator, the creation of new functionalities, and the cooperation of this complex simulator with the PV power plant. This work builds on the work done in the area of solar radiation modeling. The thesis deals with the continuation, or improvement of some shortcomings, removing shortcomings, such as fixing the beginnings and ends of the simulation, correcting the calculation of sunrise and sunset, but also adding different types of clouds, combinations of different preset cloud situations, or data input, and more. These deficiencies are found in the bachelor's thesis "Complex Simulator of the solar irradiance", and PSCAD is the main tool in this work. Another important point of this work is the realization of the simulation where an improved solar radiation simulator works in cooperation with a model of a photovoltaic panel or a PV power plant, respectively. It has different operating states created in PSCAD. These include, for example, cloud crossings, both over the entire power plant and only partial. In addition, there are experiments that prove the fact that the direction of the incoming cloud plays a role in the power of the PV power plant.

The master´s thesis deals with the design of two-stroke uniflow scavenged motorcycle engine according to patent František Pudil (PV 7018-80) 216305. The engine has been designed for using in off-road sport motorcycles. The objective of this thesis is to design the engine of this conception and to reveal benefits and defects of this concept by using this method. In this thesis the emphasis is put on design of the construction groups which are directly related to unconventional concept of engine. On the other hand, the parts which can be designed conventionally were solved marginally or were not solved at all. In the first part of the thesis there are thoroughly dicsussed expected benefits and disadvantages of this concept. Computational part focuses on valvetrain and porting of engine. Last part deals with design of engine parts.

The solar industry is one of the fastest-growing energy industries in the global market. The reason is a combination of the falling prices of modules and inverters and increased conversion to fossil-free energy production. When a photovoltaic module reaches the end of its life it needs to be replaced and discarded, which can create a sustainability problem depending on how this is managed. Today, less than 10% of the global photovoltaic waste is recycled. Only the European Union has implemented photovoltaic waste regulations in the form of the WEEE Directive, which requires that 85% of the waste is collected and at least 80% of waste collected must be prepared for reuse or recycling. This master thesis examines the energy technical, economic, and political conditions for a Swedish photovoltaic recycling plant. This is done through a literary study that is enhanced with calculations of future potential waste volumes and their economic value. As an alternative to a Swedish plant, the energy consumption for transporting waste to existing recycling plants in Europe is evaluated. The photovoltaic technologies included in this work are silicon-based mono-and polycrystalline modules, cadmium tellurium (CdTe) and copper indium gallium selenide (CIGS). Based on the calculations and the literature study, the energy technical conditions are good and not a barrier for a potential facility, the political conditions are deficient, and regulations need further development. The economic conditions constitute the largest barrier as waste volumes are not large enough for a Swedish facility to be economically profitable until 2042. The energy consumption for transport to existing recycling plants in Europe was 22 MJ/module for silicon-based mono-and polycrystalline modules and 10 MJ/module for CdTe modules. Which is a good alternative to a Swedish plant as collection processes and recycling processes are already in place.

Solar parks are increasingly getting a larger market share of PV installations over the world, and have for the last couple of years managed to establish itself in the Swedish market. The market has for a long time been known for its decline in module prices, which has allowed an emergence of more efficient PV-techniques such as one-axis trackers and bifacial modules. Bifacial modules use the backside of modules for improved utiliziation of incoming light, while one-axis trackers have the ability to track the sun in order to maximise light absorption. These innovations have now caught the interest of companies willing to invest in large-scale PV-farms, where efficient land use is highly regarded. The aim of this thesis was to examine how bifacial modules and one-axis trackers perform in terms of system performance and profitabilty if implemented in 'Solpark Fyrislund', a solar park owned by Vasakronan AB. This was done by modelling and simulating cases in which said techniques were incorporated. The data was later used to estimate profitabilty of each investigated case. Results showed that the highest system performance and profitability was achieved by installing bifacial modules on the site. One-axis trackers are currently too expensive, require higher maintenance and has a higher demand for land, resulting in its profitability not being justified. It was also found that the current configuration could be optimized further for higher profit, by slightly reducing the pitch as well as increasing the tilt of the existing modules. The study should be followed up by further investigating the use of backtracking for one-axis trackers. Said innovations should also be more established in the Swedish market so that CAPEX- and OPEX prices become more accessible.

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.

By 2020, Thailand ensured 100% electricity access to its 72 million inhabitants. This was partly done by promoting off-grid energy systems in rural areas instead of using costly grid extensions. Although electricity is ensured for all, future challenges and objectives include- increasing the share of renewable energy and decreasing energy dependence while simultaneously meeting the increasing demand. Off-grid energy solutions for rural areas have been studied in many previous projects. The most optimal energy system concerning cost, resilience, and emissions can be found by quantifying natural resources, estimating electricity consumption, and comparing technologies. This project aims to evaluate how an existing off-grid system can be complemented in the future. This was done by using the optimization program HOMER. The village Ban Wangwon, located in Prachuap Khiri Khan, was for a long time without electricity access due to a law obstructing them from connecting to the grid. This changed when in 2018, households were mounted with PV and BESS. Energy demand in the village was determined in three scenarios based on the World Banks tier system for rural energy and the previous population growth. In addition, the availability of meteorological and natural resources, energy load profile, and price of technology were determined based on the literature review and a field study. According to the results, the most optimal energy system for today's electricity use, Scenario 1, regarding both cost and emissions, was a PV/BESS system. In scenarios 2 and 3, a PV/BESS/Bio configuration proved the most cost-effective, although not optimal regarding emission rates for future energy demand. However, this system sees much lower emissions compared to when diesel generators were included, which makes this suitable for reaching Ban Wangwons requirements. Using a bio generator optimally requires a centralized energy system, requiring settlements with landowners. The biomass fuel considered in this work was pineapple crowns due to the abundance of pineapple factories and farms in the area. After a sensitivity analysis, the most impactful variables proved to be fuel prices, bio generator efficiency, and discount rate. Only one type of solar panel and battery was considered, and the load was assumed to be constant, which hindered the credibility of the results. Future projects could investigate more thoroughly how pineapple waste can be utilized in energy production, how price changes in renewable energy affect the outcome, and how a microgrid would be constructed. The results were considered beneficial in achieving SDGs 1 No poverty, 7 Affordable and clean energy, 11 Sustainable cities and communities, and 13 Climate action. / År 2020 säkerställde Thailand tillgång till el för 100% av sina 72 miljoner invånare. Detta gjordes delvis genom att främja fristående energisystem på landsbygden istället för att använda dyra elnätsförlängningar. Även om el finns tillgängligt för alla, inkluderar framtida utmaningar och mål att öka andelen förnybar energi samt minska energiberoendet samtidigt som efterfrågan på energi ökar. Fristående energilösningar för landsbygden har studerats i många tidigare projekt. Det mest optimala energisystemet gällande kostnader, resilliens och utsläpp kan bestämmas genom att kvantifiera naturliga resurser, uppskatta elförbrukning och jämföra teknologier. I detta projekt utvärderas hur ett redan befintligt fristående system kan kompletteras i framtiden. Detta gjordes med hjälp av optimeringsprogrammet HOMER. Byn Ban Wangwon, belägen i Prachuap Khiri Khan, var länge utan elektricitet på grund av en lag som hindrade dem från att ansluta till nätet. Detta ändrades när hushåll utrustades med PV och BESS år 2018. Energibehovet i byn bestämdes i tre scenarier baserat på the World Banks tier-system för energi på landsbygden samt den tidigare befolkningsökningen. Meteorologiska och naturliga resurser, energianvändningsprofil och teknikpris bestämdes baserat på en litteratur- och fältstudie. Enligt resultaten var det mest optimala energisystemet för dagens elanvädning, Scenario 1, ett PV/BESS system, avseende både kostnader och utsläpp. För de två övriga framtidsscenariorna, Scenario 2 och 3, visade sig en PV/BESS/Bio-konfiguration vara mest kostnadseffektiv, trots att den medför utsläpp. Detta system har dock mycket lägre utsläpp jämfört med dieselelgeneratorer, vilket gör det bra för att nå Ban Wangwons krav. Tillämpning av en biogenerator skulle kräva ett centraliserat energisystem, vilket skulle kräva överenskommelser med markägare. Biomassan som användes i detta arbete var ananasrester på grund av den stora mängden ananasfabriker och plantager i området. Efter en känslighetsanalys visade sig de mest påverkande variablerna vara bränslepris, bio-generatorns effektivitet och diskonteringsräntan. Endast en typ av solpanel och batteri togs i åtanke och elbehovet antogs vara konstant, vilket hindrar trovärdigheten i resultaten. Hur ananasavfall kan användas i energiproduktionen, hur prisförändringar inom förnybarenergi påverkar resultatet och hur ett microgrid skulle kunna konstrueras är alla relevanta frågor för framtida projekt. Resultaten ansågs vara fördelaktiga för att uppnå FN:s hållbarhetsmål 1 Ingen fattigdom, 7 Hållbar energi för alla, 11 Hållbara städer och samhällen och 13 Bekämpa klimatförändringarna.

Access to electricity is a crucial component of achieving SDG 7, which aims to ensure clean energy for all. However, not all people in Botswana have access to electricity, and power generation is dominated by coal power. To address the electricity access issue, the Botswana government has implemented two programs: the Rural Electrification Programand the National Electricity Standard Connection Cost Program. This study focuses on investigating the effectiveness of these government programs, as well as the drivers of and barriers to residential rooftop solar PV. The primary aim of the study is to provide recommendations for policy makers, while also contributing to enhanced knowledge among solar PV distributors and academia. To achieve the research objectives, a field trip to Botswana was conducted to interview various stakeholders. Additionally, a literature review and ananalysis of policy documents were executed. The study’s results reveal a difference in the success of the two government programs, leading to a gap between the share of grid-connected villages and the share of people with access to electricity. Interms of residential rooftop solar PV, the study identifies numerous drivers, such as increased reliability and reduced power bills. However, there are also several barriers to residential rooftop solar PV, including a conservative mindset among decision-makers that favors coal power, lack of incentives, low affordability, social acceptance risks, lacking maintenance, and insufficient knowledge among both inhabitants and policymakers. Based on the results, the study provides recommendations for policymakers to ensure full electricity access and accelerated residential rooftop solar PV implementations. / Tillgång till el är avgörande för att uppnå SDG 7 som syftar till att säkerställa hållbar energi för alla. Samtidigt har samtliga invånare i Botswana inte tillgång till electricitet och dessutom domineras elproduktionen av kolkraft. För att överkomma problemet med tillgång till electricitet har Botswanas regering implementerat programmen Rural Elecrtification Program och National Electricity Standard Connection Cost Program.  Den här studien fokuserar på att utvärdera dessa statliga program samt på att identifiera drivkrafterna och hindren för solkraft för hushåll. Det primära syftet med studien är att ge rekommendationer till beslutsfattare. Studien ämnar även bidra till ökad kunskap bland solcellsdistributörer och den akademiska världen. För att åstadkomma detta genomfördes en studieresa till Botswana under vilken intervjuer med olika intressenter hölls. Dessutom genomfördes en litteraturstudie och en analys av policydokument.  Studiens resultat påvisar en skillnad i framgång hos de statliga programmen och att det leder till att andelen nätanslutna byar är högre än andelen invånare med tillgång till el. När det gäller solkraft för hushåll har flertalet  drivkrafter för dess implementering identifieras. Till dessa hör ökad försörjningstrygghet och minskade elräkningar. Det finns dock även många hinder för ökad implementering av solkraft för hushåll. Några av dessa är ett konservativt tankesätt bland beslutsfattare som gynnar kolkraft, brist på incitament, låg betalningsförmåga, låg grad av social acceptans, bristande underhåll samt otillräcklig kunskap bland både invånare och beslutsfattande. Baserat på resultaten presenteras rekommendationer riktade till beslutsfattare för att säkerställa att alla i Botswana har tillgång till elektricitet samt för att öka implementeringen av solkraft för hushåll i Botswana.