growing concern on achieving environmental sustainability and at the same time making economical savings has become a necessity in our society. The prices of different battery energy storage technologies together with PV cells are declining all around the globe which has led to the fact that there is an increased interest in investing and using these technologies to be able to reach environmental sustainability. The combined system however, must be accurately calculated both when it comes to the sizing and the different costs related to the combined system to be able to make an economical saving. This thesis addresses both of those aspects in Sweden where a residential building with roof-top installed PV system is assessed with a battery energy storage system. An investigation is necessary to be able to assess the different battery storage technologies available in the market today with their specific technical and economical specifications. The electricity market in Sweden, the role of the Distribution System Operator on the electricity pricing with different time tariffs and fuse size subscription, PV generation and battery specifications are investigated and modeled in this study. Sizing of the different battery technologies for the given system is accomplished through a methodology that is developed in this project for the Swedish system. The calculated size of the battery is then used in the Life Cycle Cost analysis, using Monte Carlo simulations for a chosen period of 25 years.Calculations shows that the most appropriate size for the battery system with the given parameters is 6 kWh for all the battery types investigated in this study. The size of the batteries is also shown to be mainly dependent on the charging/discharging time together with the set fuse size margin. Profitability of the Battery Energy Storage system is proven to be mainly dependent on the fuse size downgrade. Sulphur-Sodium battery result in the greatest savings while Vanadium Redox batteries in the least when sizing the batteries. Lithium-Ion battery technology however is most likely to result in the lowest Levelized Cost of Electricity, total- and cycle costs while the highest Net Present Value with 90 % probability in the Monte Carlo simulations. Lithium-Ion battery technology is also found to have the highest probability of having a positive NPV compared to the lowest probability for Sulphur-Sodium battery technology. Lead-Acid battery technology is however shown to have the least uncertainties compared to other Battery Energy Storage technologies due to its maturity. It is additionally shown that government subsidy plays a crucial role when investing in the battery storage system. However, even with the case of removed government subsidy, Lithium-Ion battery technology still results in the largest probability of having a positive NPV while Sulphur-Sodium battery technology results in the lowest probability of having a positive NPV. / Den växande oron för att uppnå miljömässig hållbarhet och samtidigt göra ekonomiska besparingar har blivit en nödvändighet i vårt samhälle. Priserna på olika energilagrings teknologier så som batterier tillsammans med PV-celler minskar runt om i världen vilket har lett till att det finns ett ökat intresse när det gäller att investera och använda dessa teknologier för att kunna nå miljömässig hållbarhet. Det kombinerade systemet måste dock noggrant beräknas både när det gäller storleken och de olika kostnaderna för det kombinerade systemet för att kunna göra en ekonomisk besparing. Denna avhandling behandlar båda dessa aspekter i Sverige där en bostadsbyggnad med takmonterat PV system utvärderas med ett batteri system. En undersökning är nödvändig för att kunna bedöma de olika batteri teknologier som finns tillgängliga på marknaden idag med sina specifika tekniska och ekonomiska specifikationer. Elmarknaden i Sverige, Distribution System Operatörs roll för elprissättning med olika tidstariffer och säkringsabonnemang, PV-generation och batterispecifikationer undersöks och modelleras i denna studie. Dimensionering av olika batteri teknologier för det givna systemet uppnås genom en metod som utvecklats i detta projekt för det svenska systemet. Den beräknade storleken på batteriet används sedan i livscykelkostnadsanalysen, med Monte Carlo-simuleringar under en vald period på 25 år. Beräkningar visar att den optimala storleken för batterisystemet med de angivna parametrarna är 6 kWh för alla batterityper som undersöktes i denna studie. Batteriets storlek visar sig också vara huvudsakligen beroende av laddning / urladdningstiden tillsammans med den inställda säkrings storleken. Lönsamheten hos batterilagringssystemet visar sig vara huvudsakligen beroende av säkringens nedgradering. Svavel-Natriumbatteriet resulterar i de största besparingarna medan Vanadium Redox batteriet i de minsta när dimensionering av batteriet äger rum. Litium-Ion batteriet är emellertid sannolikt att leda till den lägsta nivån av elkostnader, total- och cykelkostnader, medan det högsta nettoförsäljningsvärdet med 90% sannolikhet i Monte Carlo-simuleringarna. Litium-Ion batteriet befanns också ha den högsta sannolikheten att ha en positiv NPV jämfört med Svavel-Natriumbatteriet som resulterar i den lägsta sannolikheten. Lead-Acid batteriet visar sig ha den minsta osäkerheten i jämförelse med andra batterilagrings teknologier på grund av dess mognad. Det framgår dessutom att statlig subvention spelar en avgörande roll när man investerar i ett batteri lagrings system. Dock även med borttagna statliga subventioner, resulterar Litium-Ion batteriet fortfarande största sannolikheten för att ha en positiv NPV, medan Svavel-Natriumbatteriet resulterar den lägsta sannolikheten för att ha en positiv NPV.

Today’s carbon constrained world with its increasing demand for cheap energy and a fossil fuel intensive fleet of power producers is making carbon capture and storage (CCS) desirable. Several CCS technologies are under investigation by various research and development groups globally. One of the more promising technologies is oxy-fuel combustion, since it produces a CO2 rich flue gas which requires minor processing to meet storage condition requirements. In this study the economics of an advanced super critical oxy-coal power plant burning lignite, simulated in-house was assessed. A robust and user-friendly financial tool box has been developed with commonly acceptable default parameter settings. Capital, operation and maintenance costs were estimated along with corresponding levelized cost of electricity and CO2 avoidance costs calculated using the detailed financial model developed. A levelized cost of electricity of 131 $/MWhrnet along with a levelized CO2 avoidance cost of 64 $/tonne was estimated for an ASC oxy-coal power plant with CO2 capture. Also a levelized cost of electricity of 83 $/MWhrnet was estimated for an ASC air-fired coal power plant without CO2 capture capabilities as the base plant. The price of electricity was observed to increase from 83 $/MWhrnet to 131 $/MWhrnet translating into a 57% increase. The sensitivity of the overall economics of the process was assessed to several parameters. The overall economics was found sensitive to the choice chemical engineering plant cost index (CEPCI), capacity factor, size of power plant, debt ratio, fuel price, interest rate, and construction duration.

Today???s carbon constrained world with its increasing demand for cheap energy and a fossil fuel intensive fleet of power producers is making carbon capture and storage (CCS) desirable. Several CCS technologies are under investigation by various research and development groups globally. One of the more promising technologies is oxy-fuel combustion, since it produces a CO2 rich flue gas which requires minor processing to meet storage condition requirements. In this study the economics of an advanced super critical oxy-coal power plant burning lignite, simulated in-house was assessed. A robust and user-friendly financial tool box has been developed with commonly acceptable default parameter settings. Capital, operation and maintenance costs were estimated along with corresponding levelized cost of electricity and CO2 avoidance costs calculated using the detailed financial model developed. A levelized cost of electricity of 131 $/MWhrnet along with a levelized CO2 avoidance cost of 64 $/tonne was estimated for an ASC oxy-coal power plant with CO2 capture. Also a levelized cost of electricity of 83 $/MWhrnet was estimated for an ASC air-fired coal power plant without CO2 capture capabilities as the base plant. The price of electricity was observed to increase from 83 $/MWhrnet to 131 $/MWhrnet translating into a 57% increase. The sensitivity of the overall economics of the process was assessed to several parameters. The overall economics was found sensitive to the choice chemical engineering plant cost index (CEPCI), capacity factor, size of power plant, debt ratio, fuel price, interest rate, and construction duration.

<div>The manufacturing cost of solar cells along with their efficiency and reliability define the levelized cost of electricity (LCOE). One needs to reduce LCOE to make solar cells cost competitive compared to other sources of electricity. After a sustained decrease since 2001 the manufacturing cost of the dominant photovoltaic technology based on c-Si solar cells has recently reached a plateau. Further reduction in LCOE is only possible by increasing the efficiency and/or reliability of c-Si cells. Among alternate technologies, organic photovoltaics (OPV) has reduced manufacturing cost, but they do not offer any LCOE gain because their lifetime and efficiency are significantly lower than c-Si. Recently, perovskite solar cells have showed promising results in terms of both cost and efficiency, but their reliability/stability is still a concern and the physical origin of the efficiency gain is not fully understood.</div><div><br></div>In this work, we have collaborated with scientists industry and academia to explain the origin of the increased cell efficiency of bulk solution-processed perovskite cells. We also explored the possibility of enhancing the efficiency of the c-Si and perovskite cells by using them in a tandem configuration. To improve the intrinsic reliability, we have investigated 2D-perovskite cells with slightly lower efficiency but longer lifetime. We interpreted the behavior of the 2D-perovskite cells using randomly stacked quantum wells in the absorber region. We studied the reliability issues of c-Si modules and correlated series resistance of the modules directly to the solder bond failure. We also found out that finger thinning of the contacts at cell level manifests as a fake shunt resistance but is distinguishable from real shunt resistance by exploring the reverse bias or efficiency vs. irradiance. Then we proposed a physics-based model to predict the energy yield and lifetime of a module that suffers from solder bond failure using real field data by considering the statistical nature of the failure at module level. This model is part of a more comprehensive model that can predict the lifetime of a module that suffers from more degradation mechanisms such as yellowing, potential induced degradation, corrosion, soiling, delamination, etc. simultaneously. This method is called forward modeling since we start from environmental data and initial information of the module, and then predict the lifetime and time-dependent energy yield of a solar cell technology. As the future work, we will use our experience in forward modeling to deconvolve the reliability issues of a module that is fielded since each mechanism has a different electrical signature. Then by calibrating the forward model, we can predict the remaining lifetime of the fielded module. This work opens new pathways to achieve 2030 Sunshot goals of LCOE below 3c/kWh by predicting the lifetime that the product can be guaranteed, helping financial institutions regarding the risk of their investment, or national laboratories to redefine the qualification and reliability protocols.<br>

Energy communities are formed to create integrated regional energy market in EU and non- EU neighboring countries. It attracts investors in generation and energy networks as it comes up with new stable regulations, so that it will ensure the supply is stable and continuous. Five EU countries (Germany, Italy, Sweden, Greece, Austria) with different policies are selected and simulations are done. Economic analysis for the 5 countries is done based on simulation results. The selected 5 EU countries shows a good economic result; therefore, it can be recommended to implement energy communities and cities by developing the directives. By transposition of policies of the energy community and implementing more subsidies or incentive will make a better contribution for the citizen partnership for creating CEC.