The expansion of photovoltaic plants has increased significantly within the EU and in Sweden, where a contributing cause has been a higher environmental thinking and lower prices for solar cell installations. Interest in installing solar cells has increased in society as a whole and an increasing number of municipalities are interested in solar cells. One of these municipalities is Forshaga municipality, which strives to be climate neutral until 2030. This study examined whether a number of selected municipal properties in the Forshaga municipality were suitable for installing solar cells based on the degree of self-use and the degree of self-sufficiency and the electricity cost of produced electricity (LCOE - Levelized cost of energy). The study also examined whether these selected properties would be suitable for solar cells if certain conditions were changed to simulate that they were located in another location with different conditions. Of the properties included in the study, there was a care home, two schools, Forshaga municipal house, a wastewater treatment plant and a waterplant. Of the examined municipal properties, a school, the nursing home and the municipal house were considered most suitable for solar cells based on the above criteria. The property that was considered most suitable was the Grossbolskolan which was the smaller of the two schools. Grossbolskolan had a self-utilization rate and a self-sufficiency rate of 87 and 15 percent respectively and the lowest cost for the produced electricity by about 0.88 SEK/kWh. The municipal house and the care home had a slightly higher production cost for the produced electricity. Some conclusions could be drawn from the part of the study that examined whether the properties were suitable for mounting solar cells if they had been placed in another location with other conditions. One conclusion was that the properties should have a similar electricity consumption as the investigated properties in this study, with a higher electricity consumption daytime when the solar cells produce the most to obtain a high self-use. The degree of selfuse was highest for the plants that were located in the east / west direction, which indicates that the electricity consumption in these type properties was more suitable for solar cell installations whose production is more widespread throughout the day. In order for the repayment period not to exceed the assumed life expectancy of the solar cell plant of 25 years, the self-use rate should not be less than 50 to 60 percent. Finally, the study also found that the properties recommended as suitable had between 1 - 3.5 m2 solar cells / MWh annual electricity use in the property, which can be used as a guideline value to see if the property is suitable for solar cells. If this value were lower, the self-sufficiency rate was low, if it was greater, the self-utilization rate was low.

The solar power accounts for only 0.2% of the Swedish power production in 2019. However, the solar power market is growing at a fast rate. Solar power production needs to be utilized instantly locally, for example in a building or else it is fed to the grid. Therefore, a challenge is how to utilize as much solar power as possible. This study aims to answer how solar panels should be placed in an optimal way in order to meet the load in a building similar to Vasakronan's property Kransen 2 in Uppsala. Two types of measures are used in the study to evaluate the solar power systems. The measure self-consumption describes the amount of solar production that is instantly used in a building. The measure self-sufficiency describes how much of the consumed solar power that covers the building's total load. The solar power production varies during the day. Therefore, the placement of panels affects the production profile during the day. The methodology in this study consists of a simulation model which provides optimal solar power systems regards to self-consumption and self-sufficiency. An economic model is also developed which calculates the payback time of solar power investments. The results shows that self-sufficiency is an important measure in order to increase the matching between a building's load and solar power production, and thereby reduce the proportion of purchased electricity from the grid. A solar power system should be optimized with regards to high self-sufficiency, and use the self-consumption to measure the amount of overproduction a system would have. A high self-sufficiency also provides a shorter payback time due to less amount of purchased electricity. The value and the relationship between self-consumption and self-sufficiency depends on the size of the system installed power.

As the construction of homes and villas in Sweden is increasing, the need for electricity will also increase. This leads us to develop new existing solutions to increase electricity production, at the same time we need to increase the use of renewable energy sources. To supply houses with sustainable and renewable energy sources, solar power is a good option to invest in. The purpose of this work is to design a photovoltaic system on a villa. Our expectation after the design is to see how much the purchased share of electricity decreases. At the end of the project, we expect that this design can be used as a model for other similar villas, it is difficult to include all villas, considering how different conditions there are in Sweden. The villa is in Hallstahammar and has an area of 138 m^2, and the roof area where solar cells are mounted is 84 m^2. The roof is facing southwest and has an azimuth of about 45°, which means that the sun shines on a large part of the roof. The villa has different roof slopes, at the garage and lower roof the slope is 20 ° and at the upper roof´s is 46 °. The report answers the questions that arise during designing a photovoltaic system, as well as the villa's annual electricity consumption, and the facility's annual electricity production once it is installed. It is then analyzed whether the installation is profitable in terms of production cost and payback time. At the end of the report, it is more discussed challenges in solar cell design, such as shading and weather and their impact on the plant's electricity production. To be able to answer the questions, various methods were used, including a literature study about solar cells to increase both interest and knowledge. The writers made saturations on the roof such as lengths, widths, and slopes. Thereafter, the simulation program PVGIS was used to calculate the plant's annual electricity production, and finally, calculations were performed to make financial calculations. The results showed that the villa's electricity consumption in 2020 was 14,272 kWh and the electricity consumption was most during the winter period. The electricity cost during that year was SEK 21,140. The photovoltaic plant produces approximately 14,185 kWh per year and that production was highest during the summer period. The payback period for the plant was just over 9 years and the production cost was SEK 0.55 / kWh. Even though electricity production and electricity consumption did not match well and were efficient in different periods, the results still showed that the investment is profitable and provides a saving of SEK 629,000 over a lifespan of 30 years.

In this thesis different methods of energy storage are evaluated for use in multifamily residential buildings in order to increase the self-consumption of self-generated photovoltaic electricity. The computational software MATLAB was used to simulate and study five different energy systems applied on two case studies. The five energy systems are; one reference system consisting of photovoltaics, one system with photovoltaics and a hydrogen storage system, and three systems consisting of photovoltaics and batteries using different management strategies. The different systems were compared based on their effect on the buildings self-consumption ratio and grid interaction as well as system costs and profitability. The battery systems successfully increased the self-consumption ratio and decreased grid interaction. Assuming a favourable development of market conditions, all systems containing batteries were paid back. The battery system that could reduce high consumption peaks during the entire year was the most profitable system as the buildings fixed grid fees could be lowered. The hydrogen storage system increased the self-consumption ratio to a small degree, as much of the electricity was lost in the conversion processes. Also, the components of the hydrogen system are very costly and the investment could therefore not be paid back within the 30 year life-time. Photovoltaics can be used to decrease variable electricity costs while energy storage can be used to decrease both variable and fixed electricity costs. The results suggest that focusing on handling power peaks and leveling grid interaction is more valuable than focusing on increasing self-consumption in multifamily residential buildings. The value of energy storage systems in multifamily residential buildings has been discussed with respect to technology development and changes in market conditions, the conclusion being that the value will most likely increase within the next decade and onward. It is believed that local energy storage systems have an important role to play in a power system with an increasing amount of renewable and intermittent power sources.

This study analyses a carport located in the Hylte municipality equipped with eight EV charging stations that use solar panels as its only roof material. The main focus of the report is to review the maximizing of internal electricity consumption, implementation of load management, effects on the local grid and to report general improvements. Data was collected from driving logs, analysis of charging patterns and the inverter. The data was then compiled with the software Polysun and MS Excel for further investigation of internal electricity consumption, load management, electricity quality and more. The report shows that there is a 29.1 % internal energy consumption and that implementation of a 100 kWh battery may raise it to as much as 57.4 %. It also shows that there is a possibility of saving up to 39 238 SEK per year with the implementation of load management and that a 19 % increase of electricity production would be possible if the construction had the optimized direction and roof angle.

Solkraft kan täcka hela jordens energibehov många gånger utan att släppa ut växthusgaser eller andra giftiga ämnen vid drift och räknas därför till en hållbar och förnyelsebar energikälla. Solkraft är därför en lämplig kandidat till att ersätta dagens ej hållbara fossilbaserade energisystem. Priset för solceller har sjunkit mycket de senaste åren. Samtidigt som Sverige och EU har som mål att minska koldioxidutsläpp ges både skattereduktion för såld överskottsel från solkraft och ett investeringsstöd. Därför kan det eventuellt vara lönsamt att installera solceller i Sverige trots begränsad solinstrålning. Det krävs att återbetalningstiden är rimlig för att privatpersoner skall bestämma sig att investera i solceller. Miljövinster är inte alls motiverande för privatpersoner enligt undersökningar. Därför bör solcellsanläggningar optimera och dimensioneras för maximal ekonomisk lönsamhet för att öka chanserna att investeringen blir av. Det här arbetet undersöker hur ett optimalt solcellssystem ska se ut ur ett ekonomiskt perspektiv för en bostadsförening bestående av 25 lägenheter i Mellansverige under olika ekonomiska förutsättningar. Störst fokus ligger på att analysera hur lutningsvinkeln förändrar resultatet. Elproduktionen hos olika konfigurationer av solcellsanläggningar simulerades fram. Dessa resultat ställdes mot byggnadens elanvändning för att beräkna hur mycket el som används till för att spara inköpt el och hur mycket som säljs för att utifrån det beräkna lönsamheten. Mest el produceras vid lutningsvinkeln 40° vilket ger marginellt mer än 30° som taket lutar. Det visar sig att lutningsvinkeln kan justeras för att öka lönsamheten men det är endast ett fåtal procent som mest. Skillnaden är som störst för små anläggningar som precis täcker baslasten för fastigheten. Bästa vinkeln för dessa mindre system är 45°. Det är svårt att motivera det dyrare montaget för att vinkla upp modulerna då taket redan lutar nära optimalt. Skillnaden mellan köpt och sparad el är liten om skattereduktion ges. Det är dock oklart hur länge skattereduktionen varar så det är därför säkrare att dimensionera utifrån sitt eget elbehov. Ett solcellssystem dimensionerat för att sälja mycket överskottsel skulle kunna bli en stor förlustaffär. Om solkraft får större plats i Sveriges elproduktion kan den ge upphov till högre globala koldioxidutsläpp beroende på vilket energislag den ersätter. Samtidigt tar det längre tid i Sverige jämfört med andra länder innan en solcell kan beräknas koldioxidneutral då det redan är mycket låga koldioxidutsläpp i Sveriges elmix kombinerat med relativt låg solinstrålning. Det innebär att solkraft ur ett miljöperspektiv är tvivelaktigt i Sverige. / Solar power is estimated to be able to cover the whole earths energy demand many times without releasing greenhouse gases or other pollutants while they operate and is therefore considered a renewable energy source. Solar power is therefore a suitable replacement to today’s fossil based energy systems. The cost for solar cells have decreased a lot in recent years. At the same time Sweden and the European Union have goals set for reducing the amount of carbon dioxide released so a tax reduction is given to those who sells overproduced electricity from solar power to the grid. This means it could eventual be profitable even in Sweden for installing solar power even though the sun doesn’t shine as much that close to the poles. It is suitable to install solar panels at buildings since it is the building and service sector that uses the most electricity in Sweden. It must be profitable for private investors before they make the choice to invest in solar panels. Environmental benefits are not as attractive for private investors. Should the solar arrays be optimized in such way that the profit is maximized the investment is more likely to occur. This paper examines how an optimal solar cell system should look like from a profitable perspective for a building with 25 apartments in the middle of Sweden under different economic conditions. Most focus is directed towards how the tilt angle affects the results. The electricity production of different configurations of solar panels was simulated. These results were then compared to the electricity demand for the building so the amount used for self-consumption and how much is sold to the grid could be calculated and from that calculate how profitable that system is. Most electricity is produced at the tilt angle of 40°, but marginally more than 30° which the roof is tilted. The difference between tilt angles are just a few percent at most. The difference is most noticeable when the system is just big enough to cover the base electricity demand. The best tilt angle for those systems are 45°. It is hard to advocate for more expensive mounting for bigger systems since the roof already is close to the optimal tilt angle. The value for saved and sold electricity is very close to each other if tax reduction is given. It’s however uncertain for how long tax reduction will last. It is much safer to size a solar array to cover the building’s electricity demand. It could be very costly to size a solar array which relies upon selling electricity with today’s economic condition. However, solar power is questionable in Sweden in an environmental perspective.

Genom detta examensarbete utvärderas den ännu oprövade tekniken Vehicle-To-Building. Tekniken bygger kortfattat på att elbilar används som tillfällig energilagring, och tillåts stötta en fastighets elektriska system genom att både ta emot och leverera effekt på önskvärt sätt. Om tekniken tillämpas och styrs på ett bra sätt väntas fastighetens totala effektuttag från elnätet kunna formas på önskvärt sätt. Att tillämpa tekniken i kontorsfastigheter är av intresse då en högre framtida efterfrågan av laddningsplatser vid dem är att vänta. Denna höjda efterfrågan kan potentiellt sett skapa negativa effekter på fastighetens ellastprofil i form av ett höjt maximalt effektbehov och ett högre energibehov. Dessutom skulle en implementering av tekniken kunna skapa möjligheter till att utnyttja egenproducerad solel på ett bättre sätt genom en bättre matchning mellan produktion och konsumtion av elektricitet inom fastigheten. För att utvärdera potentialen utvecklades en styralgoritm genom examensarbetet. Styralgoritmen arbetar för att utjämna fastighetens effektuttag från elnätet, och på så sätt minska kostnader i form av elnätsavgift samtidigt som egenförbrukningen ökar. Vidare implementerades styralgoritmen i en matematisk modell för att tillämpas vid simuleringar av ett verkligt scenario. Resultaten från simuleringarna visar hur en implementering av tekniken kan minska den negativa påverkan ett utökat antal laddningsplatser annars skulle kunna ha. Genom att även inkludera en solcellsanläggning i systemkonfigurationen visar resultaten att V2B, tillsammans med en väl konstruerad styralgoritm, kan sänka fastighetens maximala effektbehov och totala energibehov från elnätet. En viktig slutsats som dras från arbetet är vikten av en väl formulerad och konstruerad styralgoritm. Den algoritm som utvecklades visar på svagheter i förutsägelser om framtida effektbehov, vilket vidare leder till en felaktig styrning av effektflödet till elbilarna. För att en framtida implementering av V2B, eller andra liknande system som hanterar laststyrning och energilagring, framgångsrikt ska kunna göra avsedd nytta behöver alltså effektflöden styras korrekt. I annat fall riskerar en verklig implementering generera dålig effekt trots en god potential. / Due to the rise in usage of electric vehicles and changedlegislation regarding charging locations, the demand for charginglocations will most likely rise at office properties in the future. This risen demand will potentially affect the load profile of the property negatively, with a higher power peek and higher energy demand. Investigation of different solutions to handle this problem is therefor of interest. In this thesis, a control algorithm was developed. The control algorithm was designed to flatten the electrical load profile of aproperty during office hours, by allowing a bidirectional power flow between the property and electric vehicles. This bidirectional power flow, accompanied with the possibility oftemporary energy storage, is what makes Vehicle-To-Building (V2B) an interesting choice of technology. The technology also provides a possibility to increase the self-consumption rate of photovoltaic electricity. To assess the potential of V2B, the developed control algorithm was incorporated in a model to simulate an implementation in areal office property. During the simulations the number of electric vehicles were altered as well as the size of a hypothetical photovoltaic plant in order to investigate different system configurations. The results show that the standalone usage of V2B is applicable to minimize the negative effects that a more conventional loading regime possibly could give rise to. Regarding a combination of photovoltaic electricity production and V2B, the results show that even an improved load profile can be achieved if the system configuration is carefully constructed. To use V2B inorder to increase self-consumption rate of photovoltaic electricity significant either the number of vehicles need to be high, or the self-consumption rate low before incorporation of V2B. The study also provides a conclusion regarding the development of a similar control algorithms. In order to attain desired results, the incorporated algorithm needs to be precise and carefully constructed. Otherwise the full potential of the technology might not be achieved.

Med mikronät åsyftas i denna rapport en sammankoppling av solcellsanläggningar som möjliggör delning av elektrisk energi. Målet med undersökningen var att ta reda på vilka förutsättningar som gör att det är fördelaktigt att bygga mikronät. Detta har gjorts genom att undersöka två tidigare fall där mikronät varit intressant och jämföra slutsatserna från dessa fall med resultaten och slutsatserna från en egen undersökning av Södra Hemlingby där mikronät övervägs. Undersökningen av Södra Hemlingby visar att mikronät i deras fall är lönsamt och att tak som troligtvis inte skulle användas till en enskild solcellsanläggning nu kan komma till användning för solceller. Genom att bygga mikronät skulle mängden inköpt el minska, CO2-utsläpp undvikas och eventuellt skulle en högre nivå av Miljöbyggnad kunna uppnås.  Undersökningen av Södra Hemlingby visar också att ett batteri både kan användas till att reducera effekttoppar och att öka egenanvändningsgraden. Vidare dras slutsatserna att bra förutsättningar för mikronät är vid nybyggnation, när grävarbete kan göras tillsammans med andra grävarbeten, när husen som är tänkta att anslutas står nära varandra, då komponenterna i eventuellt befintligt system är kompatibla med mikronätet och således inte behöver bytas ut, då det finns storanvändare av el i systemet, när elanvändningsprofilerna matchar elproduktionen samt då det finns möjlighet till en ordentlig ökning av egenanvändning. Bäst ekonomi uppnås med en storanvändare som är bra på att ta tillvara på produktionen från solpaneler som har ett högt energiutbyte. / The term microgrid in this report refers to a link-up between solar cell plants which make sharing of electrical energy possible. The aim of this survey was to examinate the pre-requisites that makes building of microgrids meaningful. This has been completed by analyzing two earlier cases where microgrids has been evaluated. The conclusions from these cases have been compared with the results and conclusions from an own made survey of Södra Hemlingby where microgrid is considered. The survey of Södra Hemlingby shows that a microgrid would be a profitable investment and that roofs that probably not would qualify for separate plants now was useful. By building a microgrid the amount of electricity from the power distribution grid would decrease, the carbon dioxide emissions would be avoided, and possibly a higher energy classification for the building would be achieved. The survey of Södra Hemlingby also shows that a battery storage could be used for either power reduction or for increasing the own usage rate. The conclusion about good pre-requisites is drawn to be new housing estate, when ditching could be coordinated with other works, short distances between houses in the system, when the components in a existing system is compatible with a microgrid and dont have to be exchanged, when there is a large consumer of electricity in the system, when the electric consumtion profiles matches the production and when there is room for a large increas in own used electricity. Best economy is reached when large consumer of electricity is utilizing the electricity from panels with a high energy exchange.

In order to handle the mismatch between photovoltaic (PV) electricity production and household electricity use, battery storage systems can be utilized. However, the profitability of PV-battery systems in Sweden is poor, and economic incentives for households to invest in such systems are therefore missing. Hence, it is important to improve the profitability to increase the number of PV-battery installations. The aim of this thesis is to investigate the techno-economic potential of a PV-battery system offering ancillary services, more specifically the primary frequency regulation FCR-N. Five cases of residential PV-battery installations are investigated: the first with a PV system only, the second with a PV-battery system to store surplus PV electricity, and the three other cases with PV-battery systems with the ability to regulate the grid through FCR-N to varying degrees. The results show that providing FCR-N with a PV-battery system offers a substantial techno-economic potential for the system owner. By using available battery capacity for FCR-N, the payback time for a PV-battery system can be shortened significantly. With a battery price of EUR 570 per kWh (VAT excluded) and a discount rate of 2%, the payback time for the entire system can decrease from 32 to 9 years if the battery is used for FCR-N regulation. Furthermore, the payback time for a battery storage can be shortened with FCR-N. Calculated with respect to the economic added value of a battery and with a discount rate of 5%, the payback time can decrease from over 100 years to 4 years.

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.