The dissertation is an publication summary focused on the field of management processes in renewable energy systems, mathematical models and optimization possibilities for large and small scale photovoltaic systems. The articles were published in foreign impacted and reviewd journals and indexed proceedings of foreign and domestic conferences. The main results of the dissertation are the design, configuration and realization of the hybrid energy system with subsequent optimization. Using the data from the laboratory system, a mathematical model was compiled and subsequently validated in the Matlab/Simulink environment for a hybrid energy system with accumulation. The options for power production optimization with photovoltaic sources are based on both operational measurements (for commercial applications) and on the analysis of power flow controllers to optimize the~energy balance (for small scale applications in private buildings).

Master thesis deals with usage issues of autonomous, self-sufficient and decentralized systems. In the first part convectional and experimental sources for autonomous systems are disclosed. Second chapter deals with accumulation of electrical and thermal energy and possibilities of applications. 3rd part is focused on pilot project realized for autonomous and smart systems, which were built in last years. In the 4th chapter electrical and thermal energy consumption curves are made on daily and monthly basis for 4 type objects. In the fifth part issue of autonomy is explained, and for type buildings solutions are made with additional return on investment. The last chapter is focused on calculation of thermal accumulator and briefly discloses small district heating.

The diploma thesis deals with mathematical modeling of the resource allocation problem in an energy system with respect to technical parameters of the used resources. The model includes random input variables affecting the amount of demand and constraints related to associated risks. The thesis addresses control of the operation of various types of boilers and also extends the system with a heat storage tank examining its impact on the behavior of the system and achieved results. The optimization model is based on a multi-period two-stage scenario model of stochastic programming and works with simulated data, which combines real data, statistically determined estimates, and the use of logistic regression. The implementation utilizes GAMS software. When comparing the achieved results with the current state, it was found that the heat storage tank has a positive effect on the function of the system as it allows for extended usage of the cheaper unregulated sources by storing surplus heat, and thus helps to reduce the overall costs of the system.

The transition of the North African electricity system towards renewable energy technologies is analyzed in this thesis. Large potentials of photovoltaics (PV), concentrating solar power (CSP) and onshore wind power provide the opportunity to achieve a long-term shift from conventional power sources to a highly interconnected and sustainable electricity system based on renewable energy sources (RES). A multi-dimensional analysis evaluates the economic and technical effects on the electricity market as well as the socio-economic impact on manufacturing and employment caused by the large deployment of renewable energy technologies. The integration of renewable energy (RE) into the electricity system is modeled in a linear optimization model RESlion which minimizes total system costs of the long-term expansion planning and the hourly generation dispatch problem. With this model, the long-term portfolio mix of technologies, their site selection, required transmission capacities and the hourly operation are analyzed. The focus is set on the integration of renewable energy in the electricity systems of Morocco, Algeria, Tunisia, Libya and Egypt with the option to export electricity to Southern European countries. The model results of RESlion show that a very equal portfolio mix consisting of PV, CSP and onshore wind power is optimal in long-term scenarios for the electricity system. Until the year 2050, renewable energy sources dominate with over 70% the electricity generation due to their cost competiveness to conventional power sources. In the case of flexible and dispatchable electricity exports to Europe, all three RE technologies are used by the model at a medium cost perspective. The socio-economic impact of the scenarios is evaluated by a decision model (RETMD) for local manufacturing and job creation in the renewable energy sector which is developed by incorporating findings from expert interviews in the RE industry sector. The electricity scenarios are assessed regarding their potential to create local economic impact and local jobs in manufacturing RE components and constructing RE power plants. With 40,000 to 100,000 new jobs in the RE sector of North African countries, scenarios with substantial RE deployment can provide enormous benefits to the labor market and lead to additional economic growth. The deployment of renewable energy sources in North Africa is consequently accelerated and facilitated by finding a trade-off between an optimal technology portfolio from an electricity system perspective and the opportunities through local manufacturing. By developing two model approaches for evaluating the effects of renewable energy technologies in the electricity system and in the industrial sector, this thesis contributes to the literature on energy economics and energy policy for the large-scale integration of renewable energy in North Africa.:Abstract iii Acknowledgement iv Table of contents v List of tables ix List of figures xii List of abbreviations xvi 1 Introduction 1 1.1 Renewable energy in North Africa 2 1.2 Research questions and aim of this thesis 3 1.2.1 Modeling of electricity systems 4 1.2.2 Modeling of manufacturing and employment impact 6 1.2.3 Optimal renewable energy scenarios 6 1.3 Related research 7 1.4 Structure of thesis 7 2 Modeling fundamentals for electricity systems with renewable energy sources 9 2.1 Energy system modeling 9 2.2 Electricity models 16 2.2.1 Classifications and taxonomy 17 2.2.2 Differences between operation models and planning models 20 2.2.3 Typical modeling approaches 21 2.3 Optimization models 23 2.3.1 Basic model structure 23 2.3.2 Objective functions of electricity models 24 2.3.3 Technical aspects of electricity systems as models constraints 26 2.3.4 Combining different objectives in energy scenarios 27 2.4 Models for high shares of renewable energy 28 2.5 Models for North African electricity systems 31 2.6 Conclusions for model development 34 3 Electricity system of North Africa 36 3.1 Market structure 36 3.2 National targets for renewable energy 40 3.2.1 Morocco 40 3.2.2 Algeria 41 3.2.3 Tunisia 42 3.2.4 Libya 42 3.2.5 Egypt 43 3.3 Long-term development of electricity demand 44 3.4 Electricity exports to Europe 47 3.5 Geopolitical risks for the electricity system 51 4 Development of the electricity market model RESlion 53 4.1 Model requirements and modeling goals 53 4.2 Modeling of renewable energy technologies 56 4.2.1 Onshore wind power plants and wind resources 59 4.2.2 PV power plants and solar resources 61 4.2.3 CSP plants and solar resources 63 4.2.4 Hydro power plants and energy storage systems 65 4.3 General model approach of RESlion 65 4.4 Model description of RESlion 69 4.4.1 Introduction to the model structure 69 4.4.2 Temporal coverage 70 4.4.3 Objective function 72 4.4.4 Technology independent model constraints 74 4.4.5 Regional electricity exchange: Transmission lines 76 4.4.6 Renewable energy technologies 78 4.4.7 Hydro and storage power plants 80 4.4.8 Uncertainty of input parameters and assumptions 81 4.5 Modeling of expansion planning 83 4.6 Modeling of detailed hourly generation dispatch 83 4.7 Extension options to a Mixed Integer Linear Programming model 84 4.8 Solver selection and implementation environment 85 5 Model-based analysis of future electricity scenarios for North Africa 86 5.1 Scenario assumptions 86 5.2 Scenario definition 89 5.3 Technical and economic input data 94 5.4 Model adjustment 99 5.4.1 Electricity generation in reference year 2010 99 5.4.2 Testing of results with detailed hourly generation dispatch 100 5.5 Electricity scenarios for North Africa by 2050 102 5.5.1 Development of the generation system 102 5.5.2 System and generation costs 106 5.5.3 Site selection of RES generation capacities 108 5.5.4 Regional transmission lines 114 5.5.5 Energy storage systems 118 5.5.6 Technology specific generation 119 5.5.7 CO2 emissions 126 5.6 Sensitivity analyses 126 5.6.1 Adaption of market conditions: Split of electricity markets 127 5.6.2 Technology focus 127 5.6.3 Adaption of cost trends for fossil fuels, transmission lines and storage systems 129 5.7 Technology specific findings for CSP, PV and wind power 131 5.7.1 Typical sites and locations for electricity generation from RES 131 5.7.2 Influence of wind speeds and solar irradiation 131 5.7.3 Interactions with conventional power plants 132 5.8 Electricity scenarios with export to Europe 133 5.9 Discussion of RESlion model and its results 139 6 Model development for socio-economic impact analysis 142 6.1 The idea of combining a cost-optimized electricity system with a socio-economic analysis 142 6.2 Literature review and terminology 145 6.3 Data acquisition and further studies 148 6.4 Model description of RETMD 151 6.4.1 Model objectives 151 6.4.2 Model structure and decision modeling 152 6.4.3 Model limitations and uncertainties 156 6.5 Data input of RETMD 157 6.5.1 Construction of reference power plants 157 6.5.2 Operation of reference power plants 159 6.5.3 Status quo of local manufacturing in recent RE projects 160 6.6 Sensitivity of RETMD on market size and know-how 161 6.7 Discussion of model achievements 163 7 Manufacturing and employment impact of optimized electricity scenarios 165 7.1 Demand scenarios for the RE markets from 2012 to 2030 165 7.2 Economic impact and employment creation 166 7.3 Technology specific development of local manufacturing 168 7.4 Country specific development of local manufacturing 172 7.5 Potentials of local manufacturing in each scenarios 174 7.6 Local economic impact 176 7.7 Local employment impact 177 7.8 Evaluation of scenario results 181 7.9 Electricity system analysis and RE manufacturing: Results and discussion of the combined analysis 183 8 Conclusions and outlook 186 8.1 Conclusion on model developments 186 8.2 Conclusion on renewable energy in North Africa 187 8.3 Outlook and further research 189 9 Bibliography 191 10 Appendix 210

The rise in population causes serious issues in larger cities since the electrical grid is becoming overloaded. Simultaneously, the demand on more sustainable energy production and the use of renewable energy sources increase. Renewable energy based off-grid electrical systems are a possible solution to decrease the magnitude of these issues. The purpose of this thesis is to compare solar cells, solar thermal collectors and PVT (Photovoltaic thermal hybrid solar collectors) and design the most suitable combination of solar panels for a selfsufficient multi-family house in Jönköping, Sweden. The solar panels were compared from a cost and energy production perspective, then a suitable renewable energy system with all three types of panels was constructed and optimized using Opti-CE, which is a MATLABbased software. During the course of this thesis, an interview was made with Hans-Olof Nilsson who is a co-founder of Nilsson Energy and owner of a self-sufficient off-grid house. The results show that PVT-panels have higher energy production per area and 22% higher LCC (life cycle cost) than regular solar cells in combination with solar thermal collectors. Optimization results indicate that the house cannot be self-sufficient by installing solar panels on the given roof area only, rather the area of installed solar collectors should be increased to a minimum of 1497𝑚2 . With the given roof area of 900𝑚2 the house can only be self-sufficient a maximum of 75% of the time. The results also indicate that the introduction of compact systems with the simultaneous decrease of cost will make renewable off-grid energy systems more attractive in the future.

Pakistan, though being one of the most rich in renewable energy resources, faces serious energy crises and has a shortfall of about 6 GW electric energy. Most of the resources are untapped until today. The fuel for electricity production is being imported and is of high cost. The government is trying to fulfill the energy requirements of the industries and urban areas where rural areas are at the lowest priority. Pakistan was hit by flood disaster in 2010. There are number of organizations, governmental and private, that are trying to provide shelters and basic necessities to the flood affecties even until today. Village Goth Mehdi Farm in Sajawal area of Sindh is one of the examples of a newly built village for the flood affecties. It has been built with the help of Pakistan Navy, however, the village is bereft of electricity. This report presents three different designs for the electrification of the flood affected village, consisting of 20 houses, a mosque, a community centre, toilets and street lighting, in Sajawal, Pakistan by utilizing available renewable energy resources using sustainability approach. Supply of clean water and energy for cooking purposes was also investigated. However, it was identified in the site visit that villagers were using a mechanical hand pump to pump the underground clean water for daily usage which did not require further alternative. The village is surrounded by wheat fields and trees, and villagers used wood as fuel for cooking. Dehydrated animal dung of cattle was also used as fuel source. The Sajawal area is located in the wind corridor of Sindh and also receives sun light of high insolation level. Thus, wind turbine (WT) or/and PV module can be used for electricity generation, respectively. Based on such advantages three electricity generating systems are proposed. Option #1: solar energy by using 19 kilowatt Photovoltaic (PV) system with off grid inverter and battery bank to cater the load of the village, Option #2: wind energy by using 20 kilowatt wind turbine with a battery backup and Option #3: hybrid PV and WT system with 5.8 kilowatt PV system combine with 10 kilowatt wind turbine and battery backup. These systems have been designed by keeping social, economical and environmental aspects in account. The financial comparison showed that the option # 1 required highest amount of capital cost with respect to other options, while option # 3 needed lowest initial investment for installation. Moreover Option 1, solar system, was found to be the most expensive option when battery replacements (every 3 years) were considered over a 20 years life time. Option 3, hybrid wind and solar system, was concluded to be the most economical solution for the Goth Mehdi farms.

The study aims to identify the reasons behind power shortages in the city Sulaymaniyah, located in northern Iraq or Iraqi Kurdistan, and to clarify how large the difference between power demand and supply is. Also, several interviews have been performed to give further insight to the issues and possibilities the region is facing. Nevertheless, a portion of the energy demand is met by local diesel generators supplying power in city districts. With the use of the software program ArcGIS, a mapping of all the diesel generators in the city districts is done in order to visualize the unsustainable conditions of the city. In addition, the energy output of the diesel generators is quantified, and the energy supplied to a household is estimated on an average. Later, calculations are performed to estimate the diesel generators price for electricity, their amount of annual CO 2 emissions and social costs. In order to bring light to renewable energy solutions, a solar PV configuration was chosen based on regulations and infrastructure issues in the region, suitable for households. Furthermore, with the use of intra-hour solar irradiance data from Meteonorm and the software Matlab, an optimal solar PV angle was calculated for Sulaymaniyah. Thereafter, the goal was to substitute diesel generated energy with solar PV energy and thus a solar PV system was estimated for a typical household based on; the average energy received from diesel generators, the solar PV system’s efficiency and the total solar irradiance striking the tilted panels. Furthermore, a Net Present Value was calculated to evaluate the economic profitability of the solar PV investment. Lastly, a sensitivity analysis was done with different scenarios to predict different outcomes of the NPV model. The study found that the energy system in Iraqi Kurdistan is unreliable and unsustainable, mostly due to infrastructure issues and political uncertainties. Due to these issues, power shortages occur on a daily basis and the difference between power supply and demand reached an average of 350 MW throughout 2018, and the largest difference reached 1304 MW. The number of diesel generators in the city was 525 and had a combined installed capacity of 176.6 MW, however they are usually working at 85 % operational efficiency resulting in a power supply of 150.1 MW. Additionally, it was estimated that a household receives an average of 920.07 W from the diesel generators. Furthermore, the calculated price for electricity was 207 IQD/kWh and all the generators combined pollutes approximately 319000 tons of CO 2 per year. The optimal angle for a solar panel in Sulaymaniyah was calculated to 21° and the recommended configuration for a solar PV system for households was a stand-alone battery storage system. In order for households to replace the diesel generators they need a capacity of 1.62 kW and a dimensioning of 9.66 m 2 . Finally, based on the NPV model it was found that it is economically profitable to invest in a solar PV system with today’s conditions. However, the investment is profitable with a relatively small margin and based on a scenario analysis, it showed that the investment might easily become unprofitable with the change of the discount rate. Lastly, it can be discussed that the actual demand in Sulaymaniyah is lower than the one presented, since it is artificial and very dependent on peoples consuming behaviors which might be different if they were to have access to electricity all the time. Also, one of the biggest obstacles that might hinder solar PVs to be integrated to the energy system is the net-metering, regulations and tariff issues. The KRG clearly does not give incentives to its people to invest in renewable energy, which also might be the reason why there is a very small market in Sulaymaniyah.

The Swedish energy sector is undergoing transformational changes. Along with a rapid growth of renewables and a shift towards electromobility, the transformation is expected to bring challenges to the power system in terms of grid instability and capacity deficiency. Integrating distributed renewable electricity production into the electric vehicle (EV) charging infrastructure is a promising solution to overcome those challenges. The feasibility of implementing such a charging infrastructure system in northern Sweden is however uncertain, as the solar resources are scarce in the long winter period. This study aims to maximise the value of a solar powered EV charging station, placed in a workplace environment in Umeå. An integrated system model of the charging station is developed, comprising separate models of a solar PV system, a battery energy storage system (BESS), the workplace EV fleet and the building Växthuset, onto which the charging station will be installed. Three scenarios are developed to study the charging station’s system performance under different EV charging strategies and BESS dispatch strategies. Two additional scenarios are developed to study the potential grid services that the charging station can provide in the winter period. A techno-economic assessment is performed on each scenario’s simulation results, to measure their effect on the charging station’s value. It involves analysing the charging station’s profitability and how well the BESS is utilised by the end of a ten-year project period. The charging station’s grid impact is further assessed by its self-consumption of solar power, peak power demand and the grid energy exchange. The assessed charging station values indicate that the overall grid impact was reduced with dynamic EV charging strategies and that the BESS capacity utilisation was strongly influenced by its dispatch strategy. The charging station further implied a net capital loss under the explored scenarios, even while the dynamic charging strategies brought by a slightly increased economic value. Moreover, the studied winter scenarios showed a great potential for the charging station to provide ancillary services to the local distribution grid while maintaining an efficient BESS capacity utilisation. The winter period’s peak power demand was significantly reduced by optimising the BESS operation to shift peaks in the building’s load profile, and peaks caused by the additional EV charging demand and the EV heaters, to off-peak hours. On this basis, future research is recommended for improved simulations of the charging station operation and to study additional value-added features that the solar driven charging station can bring. / Sveriges energisystem genomgår en omfattande omställning. Förändringar i form av en ökad andel förnybar elproduktion och elektrifieringen av transportsektorn förväntas medföra stora utmaningar för elsystemets nätstabilitet och överföringskapacitet. Att integrera in distribuerad, förnybar elproduktion som en del av laddinfrastrukturen för elfordon ställer sig som en lovande lösning för att möta de väntande utmaningarna. Möjligheterna att tillämpa en sådan lösning i norra Sverige är däremot mindre självklara, då solresurserna är knappa under vintertid. Det här examensarbetet syftar till att maximera nyttan av en soldriven laddstation för elbilar, placerad på ett arbetsplatsområde i Umeå. En integrerad energisystemmodell av laddstationen har skapats, bestående av systemmodeller av solpaneler, ett batterienergilager, arbetsplatsens elbilsflotta samt byggnaden Växthuset, som laddstationen ska anslutas till. Tre scenarier har utformats för att undersöka hur laddstationens prestanda förändras beroende på olika laddstrategier för elbilarna och batterienergilagrets styrning. Ytterligare två scenarier har utvecklats för att utforska möjliga nättjänster som laddstationen kan bistå med under vintertid. Laddstationens värde har vidare bedömts utifrån systemets prestanda i de olika scenarierna. Bedömningen grundar sig på laddstationens lönsamhet och hur välutnyttjat batterienergilagret är efter en kalkylperiod på 10 år, samt på specifika påverkansfaktorer på elnätet. Faktorerna omfattar konsumtionen av egenproducerad el, toppeffektuttaget och nätöverföringarna orsakade av laddstationen. Från värderingen av laddstationen framgår det att de dynamiska laddstrategierna ledde till en, överlag, minskad påverkan på elnätet samt att styrningen av batterienergilagret hade stor inverkan på dess utnyttjandegrad. Laddstationens nettonuvärde förblev negativt i de tre scenarierna, även om de dynamiska laddstrategierna, ökade dess ekonomiska värde till en viss del. Vidare tyder simuleringen av vinterscenarierna på att det finns en stor potential för laddstationen att erbjuda tjänster för lokalnätet och samtidigt nyttiggöra sig av batterienergilagret. Växthusets toppeffektuttag reducerades märkbart genom att optimera batteristyrningen till att flytta effekttoppar orsakade av Växthusets ellastkurva eller elbilarnas laddning och uppvärmning, till de timmar där lasten var lägre. Med detta i bakgrund föreslås vidare studier som fokuserar på den integrerade energisystemmodellen för att förbättra simuleringarna, samt att undersöka möjligheterna till att erbjuda fler nättjänster, som ökar laddstationens mervärde.

About a third of Mozambique’s population has access to electricity, and the same number in rural areas, where most of the population lives, is down to 5 %. Small-sized off-grid solutions are economical alternatives to increase the electricity access rate in rural areas, and solar power is a common energy source due to price and weather conditions. Still, the economical aspect is the main hindrance to an increased electrification rate in Africa. This report aims to investigate how to make electricity affordable, in a sustainable way, by answering the main research question “What is the capability, economically, socially, and technically, for a shared nano off-grid system in the village Linga Linga?”. This was done by performing a Minor Field Study in the village Linga Linga, in southern Mozambique, with the help of the non-profit organization Project Vita. A collective nano-grid photovoltaic (PV) system was installed to electrify three households, including nine houses and eleven people, where the wage earners are all women. Before the construction and installment of the PV system, the first round of two interviews was conducted to investigate the energy situation for the households. After the interviews, the main components of the energy system: PV panels, inverter, charge controller, batteries, and cables, were sized and purchased. The energy system was sized to cover an energy demand of eleven Light-Emitting Diode (LED)-lights, four 3 W and seven 5 W, lit all day and all night, and three outlets for charging cell phones eight hours a day. This corresponds to an energy demand of 1,369 Wh per day, and a maximum power demand of 77 W. The resulting system cost is 87,570 Mozambique Metical (MZN), or 1,400 United States Dollars (USD). When calculating the technical lifetime to be 20 years, three of the main components must be replaced. That results in a system cost of 122,470 MZN, 1,960 USD, and the cost per wage earner of the participating households is 4.3 % of the average Mozambican’s annual salary. After the system had been running for about a week, the second round of interviews was carried out. On the same occasion, the households were informed about the maintenance and usage of the system, and they were handed manuals and contracts to sign. The interviewees reported that they had been working for more hours a day, handicrafts being their main source of income, thanks to the electric lights. The women were positive about collective ownership and sharing electricity and stated that they prefer a collective system to separate ones, even for the same cost. The interviews showed that the energy demand was lower than what the system was sized for, meaning that a system designed for the actual energy demand would have been both cheaper and smaller. However, the energy behavior could change with time as society develops and the users get more familiar with electricity. No clear answers were obtained regarding the willingness to pay (WTP) for the system, and the interpretation is that the household, in their current situation, cannot consider buying an energy system comparable to the prototype built for this report, due to the system cost. A collective solar nano-grid in rural Mozambique is concluded to be a well-functioning solution and one of the more economical electrification alternatives. Although the prototype in this study was too expensive for the participating households to pay for by themselves, it could support sustainable development and open for possibilities like increased productivity and income. Moreover, it could be expanded by connecting more loads and upscaling to further cut the system cost per person and increase the societal benefits. / Ungefär en tredjedel av Moçambiques befolkning har tillgång till elektricitet, och motsvarande andel på landsbygden, där majoriteten av befolkningen bor, är 5 %. Mindre off-grid lösningar är ekonomiska alternativ för att elektrifiera landsbygden, där solkraft är en vanlig energikälla på grund av det relativt låga priset och väderförhållandena med goda förutsättningar. Den ekonomiska aspekten är dock fortfarande det främsta hindret för att öka Afrikas elektrifieringsgrad. Den här rapporten syftar till att undersöka hur elektricitet kan göras tillgänglig för alla, på ett hållbart sätt, genom att besvara frågeställningen ”Vad är möjligheterna, ekonomiskt, socialt, och tekniskt, för ett delat nano off-grid system i byn Linga Linga?”. Detta utreds genom att genomföra en Minor Fields Study i byn Linga Linga i södra Moçambique med hjälp av välgörenhetsorganisationen Project Vita. Ett nano-nätsystem drivet av solceller installerades, innefattande tre hushåll med nio hus och elva personer, med endast kvinnliga inkomsttagare. Innan byggnationen av solcellssystemet genomfördes intervjuer för att undersöka hushållens energisituation. De mest fundamentala systemkomponenterna; solcellspaneler, växelriktare, solcellsregulator, batterier och kablar, dimensionerades och införskaffades efter intervjuerna. Energisystemet utformades efter ett energibehov på elva Light-Emitting Diode (LED)-lampor, varav fyra 3 W och sju 5 W, tända dygnet runt, och tre uttag för att ladda mobiltelefoner åtta timmar om dagen. Detta motsvarar ett energibehov på 1,369 Wh per dag, och ett maximalt effektbehov på 77 W per dag. Den resulterande systemkostnaden är 87 570 Mozambique Metical (MZN), eller 1 400 United States Dollar (USD). För att räkna om systemkostnaden för en teknisk livslängd på 20 år måste tre av systemets huvudkomponenter bytas ut, vilket resulterar i en systemkostnad på 122 470 MZN, 1 960 USD. Kostnaden per inkomsttagare i de deltagande hushållen utgör då 4,3 % av den årliga moçambikiska medelinkomsten. När solcellssystemet varit i gång i en vecka utfördes en andra omgång intervjuer. I samband med detta informerades hushållen om skötsel och användning av systemet, och mottog manualer och kontrakt. Det framkom att kvinnorna, tack vare den elektriska belysningen, hade kunnat arbeta längre på kvällarna med sina hantverk - deras främsta inkomstkälla. De var positiva till det kollektiva ägandet av systemet och sade sig föredra ett delat system framför varsitt separat, även för samma kostnad per person. Intervjuerna visade att hushållens energikonsumtion var mindre än systemet var designat för. Ett system anpassat efter det verkliga energibehovet hade därmed blivit både mindre och billigare. Energianvändandet kan dock förändras i takt med samhällsutveckling och användarnas bekantskap med elektricitet. Inga tydliga svar angående betalningsvilja (WTP) för systemet mottogs, och tolkningen är att hushållen, i deras nuvarande situation, inte kan tänka sig köpa ett energisystem som är jämförbart med studiens prototyp, på grund av den höga systemkostnaden. Ett soldrivet kollektivt nano-nät på Moçambiques landsbygd bedöms vara en välfungerande elektrifieringslösning och ett av de mest ekonomiska elektrifieringsalternativen. Fastän studiens prototyp var för dyr för att de deltagande hushållen kan det ses stödja en hållbar utveckling genom att öppna upp för möjligheter såsom ökad produktivitet och inkomst. Systemet skulle även kunna expanderas genom att koppla in fler eller större last, och byggas i större skala för att dra ner systemkostnaden per person och öka samhällsnyttan.

Efforts to mitigate climate change and current geopolitical disruptions have revealed that changes to the existing energy system are urgently required to offer sustainable and secure energy for Europe. Hence, the role of conventional thermal power plants is being challenged and new technologies providing additional functionality for the power grid are pushing into the market. Thus, system perspectives and considerations of synergies between different technologies become more important. Current research efforts are focused on the hybridization of renewable technologies, sector coupling, and repurposing of existing energy infrastructure. Nevertheless, literature is still lacking a system perspective analysis of these combined topics. For this purpose, a case study on integrating the existing Mellach combined cycle gas turbine (CCGT) power plant into a hybrid energy system dominated by PV and wind power via hydrogen production facilities is performed. The performance of this innovative storage power plant (ISPP) is assessed through an optimization-based techno-economic-environmental analysis. Further, the sensitivity of such a system to external uncertainties such as the electricity price, component costs, or CO2 emission pricing is evaluated.  Under the assumptions made, the retrofitting of the CCGT to be (co-)fired with hydrogen does not provide an economically feasible solution for repurposing the power plant. The results indicate that the highest revenues are obtained when natural gas firing in the CCGT is enabled. Simultaneously, this also causes the highest CO2 emissions. However, natural gas needs to be phased-out by 2030 to meet Austria’s climate target. Combining renewables with hydrogen-firing of the CCGT system or sales to the hydrogen market increases the system flexibility and resilience to external influences. However, the revenue streams from continuing the CCGT operation cannot offset the initial investment costs of the turbine upgrade. The investigated ISPP is subject to several uncertainties. Depending on the development of certain components or market properties, utilizing the existing power block through sector coupling with hydrogen can improve the system economics. Eventually, this can make the system profitable depending on the developments. The investigated system behavior shows an improved utilization of renewable energy by converting it into hydrogen instead of curtailing or selling the electricity at a low price. Hence, the investigated set of components is most profitable when the installed renewable energy capacity is a multiple of the maximum electric power of the existing CCGT power block. On the other hand, providing the option of blending natural gas with hydrogen is not economically beneficial under the assumptions made. Further, the results showed that an increase in EU ETS CO2 certificate prices would improve the profitability of the ISPP compared to the state-of-the-art operation with natural gas. Another finding of the analysis is the sensitivity of the hydrogen system to the electrolyzer cost. Meeting the near-term electrolyzer cost development target would significantly increase the optimal hydrogen system sizing, as well as the economic performance of the entire power plant. Additionally, the system can balance the power grid by operating the electrolyzer using grid electricity purchased at negative prices during hours of power oversupply, which is not possible in the existing configuration. It can be concluded that the investigated ISPP is more resilient to external influences given its enhanced operation flexibility and different revenue streams. / Bemötande av klimatförändringar och nuvarande geopolitiska störningar har avslöjat att förändringar av det befintliga energisystemet är nödvändiga för att erbjuda hållbar och säker energi för Europa. Därför ifrågasätts rollen för konventionella termiska kraftverk och nya teknologier som erbjuder ytterligare funktionalitet för elnätet gör sin inmarsch på marknaden. Därmed blir systemperspektiv och överväganden av synergier mellan olika teknologier allt viktigare. Aktuell forskning fokuserar på hybridisering av förnybara teknologier, sektorkoppling och omdaning av befintlig energiinfrastruktur. Trots detta saknas fortfarande en systemperspektivsanalys av dessa kombinerade ämnen i litteraturen. För detta ändamål genomförs en fallstudie om integrering av det befintliga kombikraftverket (CCGT) i Mellach i ett hybridenergisystem dominerat av sol- och vindkraft via vätgasproduktionsanläggningar. Prestandan för detta innovativa lagringskraftverk (ISPP) utvärderas genom en optimeringsbaserad teknisk-ekonomisk-miljömässig analys. Dessutom utvärderas känsligheten hos ett sådant system för externa osäkerheter som elpriset, komponentkostnader eller prissättning av koldioxidutsläpp. Under de antaganden som gjorts ger ombyggnaden av CCGT för att använda (co-)eldning med vätgas inte en ekonomiskt genomförbar lösning för omdaning av kraftverket. Resultaten indikerar att de högsta intäkterna uppnås när naturgaseldning i CCGT tillåts. Samtidigt orsakar detta också de högsta koldioxidutsläppen. Dock behöver naturgas fasas ut före 2030 för att uppnå Österrikes klimatmål. Att kombinera förnybara energikällor med vätgaseldning av CCGT-systemet eller försäljning till vätgasmarknaden ökar systemets flexibilitet och motståndskraft mot externa påverkan. Intäktsströmmarna från fortsatt drift av CCGT kan dock inte kompensera för de initiala investeringskostnaderna för uppgraderingen av turbinen. Det undersökta ISPP påverkas av flera osäkerheter. Beroende på utvecklingen av vissa komponenter eller marknadsegenskaper kan användningen av det befintliga kraftblocket genom sektorkoppling med vätgas förbättra systemekonomin. Slutligen kan detta göra systemet lönsamt beroende på utvecklingen. Det undersökta systembeteendet visar en förbättrad användning av förnybar energi genom att omvandla den till vätgas istället för att avbryta eller sälja el till ett lågt pris. Därför är det undersökta komponentsystemet mest lönsamt när den installerade kapaciteten för förnybar energi är flera gånger den maximala elektriska effekten hos det befintliga CCGT-kraftblocket. Å andra sidan är möjligheten att blanda naturgas med vätgas inte ekonomiskt fördelaktig under de antaganden som gjorts. Dessutom visade resultaten att en ökning av EU ETS-koldioxidcertifikatpriserna skulle förbättra lönsamheten för ISPP jämfört med dagens drift med naturgas. En annan slutsats från analysen är känsligheten hos vätgassystemet för elektrolysatorns kostnad. Att uppnå den närtidsmål för kostnadsutveckling för elektrolysatorn skulle signifikant öka den optimala storleken på vätgassystemet, liksom den ekonomiska prestandan för hela kraftverket. Dessutom kan systemet balansera elnätet genom att driva elektrolysatorn med el från elnätet som köps till negativa priser under timmar av överflödig kraft, vilket inte är möjligt i den befintliga konfigurationen. Slutsatsen är att det undersökta ISPP är mer motståndskraftigt mot externa påverkan med tanke på dess förbättrade driftflexibilitet och olika intäktsströmmar.