Ökade miljökrav tillsammans med ett statligt stöd och en ökad miljömedvetenhet hos gemene man har medfört att intresset för förnybar elproduktion har vuxit. I takt med sjunkande priser på solceller tack vare ökad konkurrens samt massproduktion kan ett fortsatt ökat intresse förväntas. Syftet med studien är att undersöka hur spänningen i lokalnätets lågspänningssida i landsbygden påverkas av nätanslutna solcellssystem. Samt hur effektförlusterna påverkas. Frågeställningarna var, hur stor installerad effekt kan anslutas utan att acceptansgränsen överskrids eller transformatorer överbelastas, även spänningsvariationer och el kvalitéten utifrån dess regelverk togs hänsyn till samt hur företaget kan påverkas ekonomiskt. Materialet som användes i studien bestod av simuleringar och nätberäkningar på två lågspänningsnät utförda i dpPower. I det ena nätet simulerades både en-och trefasigt anslutna solcellsanläggningar med märkeffekt 4,5 kW i olika driftscenarion. I det andra nätet simulerades enbart trefasigt anslutna anläggningar med märkeffekter mellan 4,5 kW och 17 kW. I samtliga driftscenarion råder, vid anslutning av solceller, lägsta förbrukning hos abonnenter framtagna från bearbetade timvärden för ett helt år. Erhållen data för samtliga anslutningspunkter sammanställdes och analyserades i Excel. Där valdes att grafiskt presentera några av de anslutningspunkter där otillåtna händelser uppstod, vilka var överspänning, spänningsförändring vid inkoppling samt spänningsobalans. Det som tydligast framgick var att enfasigt anslutna anläggningar påverkar nätet negativt i mycket större utsträckning jämfört med trefasigt utförande. Vidare visade resultatet att storleken av den totala installerade effekten kan vara lika stor som transformatorns märkeffekt, utan att transformation överbelastas. Däremot undersöktes inte effekt för acceptansgränsen vidare, då det visade sig att mer intressant var att identifiera nätets svaga punkter som kom att sätta gränser för vilka effekter som var möjliga att ansluta. Målet med studien var att resultatet kan ligga till grund för en utveckling av handlingsplan samt fortsatt analys hos Dala Energi AB, gällande anslutning av mikroproduktion, i kombination med rekommenderade förfaranden beskrivna i Svensk Energis rapport MIKRO.

Solcellsteknik med nätanslutning är relativt nytt i Sverige och lagarna är oklara vad gäller anläggningar på bostadshus villor och offentliga hus. I analysen redovisas den ekonomiska aspekten av producerad solcellsel och konsumtionen av denna. Solcellsanläggningen på kommunhuset i Mönsterås har studerats, varvid följande resultat har framkommit: från de installerade solcellerna (210 kvm), får man 10 % av den totala energiförbrukningen i byggnaden. Kostnaden för solcellerna och installationen av dem är subventionerade av staten med 70 %. För den resterande kostnaden skulle solcellerna vara i bruk i 24 år för att täcka kostnaden. Produktionen och förbrukningen i kommunhuset i Mönsterås har jämförts med två solcellsanläggningar i Malmö och Göteborg (hur stor del av den el som förbrukats av Malmö kårhus och av äldreboendet i Göteborg har utgjorts av el från solcellsanläggningarna). Det visade sig att även Malmös och Göteborgs solceller, stod för cirka 10 % av deras totala energiförbrukning, vilket visar att den teoretiska beräkningen av Mönsterås solceller stämmer. Lennart Söders förslag om nya bestämmelser är till för att utveckla och stödja utbyggnaden av nya förnybara källor. Det har visat sig att det är för stor skillnad mellan stora (större än 1500 kW)och små (max 1500 kW) anläggningars kostnader för anslutning och elöverföring till nätbolag. Elbolagens höga kostnader för elmätning, som krävs för elcertifikat har gjort att många valt att inte skaffa dessa elcertifikat. Elcertifikaten är till för att stödja utvecklingen av förnybara energianläggningar. Därför har Söder även gett föreslag till ett skäligt sätt att läsa av sin egen mätare enklare. Lennart Söder föreslår att avgiften för de små anläggningarna ska vara 3öre/kWh plus en fast kostnad för mätning, beräkning och rapportering av nätkoncessionshavarens nät under max. 10 år från produktionsstart. Från 2015 betalar alla full årlig nätavgift. Anläggningar med max 63 amperes säkringsnivå och som är anslutna till lågspänningsnät ska inte behöva rapportera timvis utan månadsvis. De ska dessutom själva kunna göra mätning och rapportering för elcertifikat. De lagar som diskuteras i denna analys är 4 § (2003:113) som handlar om ändring i elcertifikat och ellag (4 kap. 10 § 1997:857). Lönsamheten av en investering i en solcellsanläggning är beroende av tre faktorer; elpriset på elmarknaden, solcellernas pris på marknaden och bestämmelserna om mätningskostnaden av förnybar energi. leder Det kan inte bli lönsamt förrän elpriset har stigit och solcellsystemen har sjunkit i pris, så att de ligger i samma prisklass som inköp av el från ett elbolag.

This study aims to examine the hosting capacity (the maximum amount of distributed generation possible to add to a current grid) of Mälarenergi’s distribution networks. The three areas examined are a rural network, a modern suburban grid and an older suburban grid. The networks are modelled in PowerWorld Simulator with data mainly from Mälarenergi’s NIS (Network Information System). The basic models include calculated minimum loads based on load profiles, combined with 0 kW, 2 kW, 4kW or 5 kW installed photovoltaics (PV) systems at each consumer. The compensating models are based on the previous ones but with reduced transformer voltages to lower the risk of grid over-voltages. A high load case is also examined to make sure there are no under-voltages for these models. The results show that the rural network is strong enough to handle the biggest available PV system at 5 kW, if the transformer voltage is lowered from 1.03 p.u. to 1.005 p.u. The modern suburban grid can host 4 kW solar panels together with a lowered voltage level of 1.005 p.u. The larger package of 5 kW leads to overloading at the transformer when used. The older suburban grid has the largest issues with both overvoltages and overloading and can only handle 2 kW distributed generation with a voltage reduction to 1.005 p.u. The models are fairly sensitive because of assumed transfomer parameters and, in the case of the modern suburban grid, some lines being removed due to limitations in the software. Regardless, the results are robust enough that they can be considered correct.

The study examines the potential for extensive connection of photovoltaic (PV) production in the Swedish rural power grid, considering the case distribution grid (10kV) of Herrljunga Elektriska. Hourly PV production is calculated using radiation and temperature data together with information regarding building roofs in the studied area. Furthermore, hourly customer load data is aggregated, enabling detailed power flow simulations of the grid resulting in hourly voltages and currents for all nodes during 2014. Three cases with varying PV production are studied, using different thresholds for minimum annual radiation. Thus, roofs with lower annual radiation are excluded from the simulations, limiting PV production. The three cases considers annual radiation greater than 0 kWh/m2 , 700 kWh/m2 and 1000 kWh/m2. Simulations show that the distribution grid in Herrljunga maintains acceptable performance with respect to voltages and currents for the 1000 kWh/m2,year case, yielding an annual production of 30 % of consumption. The hosting capacity, which is an estimate of the amount of PV that can be connected to the grid, is therefore 30 %. In order to further examine grid limitations, weak parts of the grid are identified. These are situated in the peripheral parts of the grid, which is in accordance with earlier studies of intermittent power production in distribution grids. Additionally, low voltage grids in connection to these weaker parts of the distribution grid are simulated, showing no further limitations for hosting capacity.

This thesis aims to contribute to improved functional procurement of photovoltaic systems, PV systems. Functional procurement means that criteria concerning a function are set rather than specifying technical details or products. Possible advantages and difficulties in using functional procurement have been analyzed by interviews, simulations and a case study. Electricity production and surplus production for different scenarios have been simulated via MATLAB. The MATLAB script was also used to generate rules of thumb on feasible solar fraction for six different load profiles; a church, a farm, a car mechanic, an office, an industry and an apartment building. The results show that functional procurement promotes innovative solutions and is likely to increase customer satisfaction. The entrepreneurs get increased responsibility for the PV installation and the monitoring of it. Difficulties in using functional procurement of PV systems include uncertainties in irradiance and division of responsibilities. It is therefore important to define in what circumstances the functions should be met. The evaluation of the case study shows that the demands that were set were hard to accomplish, but if the maximum simulated surplus production would have been 6 % instead of 5 % of the summer weekdays, it would have been easier. The rules of thumb show that depending on load profile and accepted proportion of surplus production, the yearly solar fraction is between circa 10 % and 30 %. This number is lower for businesses that close during the summer and higher for businesses that have a load profile that corresponds well with the irradiance.

The increase of variable renewable source leads to an imbalance between the electricity supply and demand of the power grid, as the solar and wind energy production is weather dependent. By implementing battery energy storage system (BESS), the balance can be improved by storing energy when the supply is high and then use when the supply is low. The aim of this study is to investigate the profitability of implementing a BESS with a photovoltaic plant to the grid connected facility of Gävle Energi AB. This by mapping the potential revenues that can benefit both the property and power grid. The aim is also to investigate the cost saving of a BESS with an optimal control and then look at the sizing of the battery.   At the Swedish battery market there is two technologies, lithium ion and nickelmetal hybrid, both of which have different characteristics that affect its service life. The battery life is affected by its chemistry, state of charge, depth of discharge, charge rate, temperature, and operating conditions. One of the revenues with BESS are to take advantage of the price difference and charge the battery when the electricity price is low and discharge when it is high. The revenue is also to increase the self-use of solar power to the facility, peak shaving, and frequency control. You can also use the BESS as an emergency power due to its fast output power. The simulation was built in the program Excel containing eight different tasks, all with different battery sizes. Each task contained four control models; increase selfuse of solar power, peak shaving, frequency control and a combination of the three. This with input data from both 2018 and 2019.  The result showed that the best savings in all tasks occurred with the frequency control model or the combination model. The size of battery depends on the service life. The battery lift is hard to predict and thus also the choice of battery size. As the control model affects the battery life, the ideal battery life of 20 years can be difficult to achieve. Therefore, a BESS of 100 kWh may be recommended. Except as a property revenue, the BESS may reduce some percentage of marginal electricity and thus also the carbon dioxide emissions and may also support the power grid with frequency control.

The urgency for firms to acknowledge and correct for their carbon footprint is increasing in scale and importance. A key to long run firm survival lies in whether companies take their Corporate Social Responsibility (CSR) seriously. At the same time, a combination of supportive policies, innovation and increased market competition has enabled a remarkable increase in the share of renewable energy. Adopting renewable energy solutions can be a CSR tool for a firm. One way in which a firm can do this is by installing solar power systems. The aim with this thesis is to gain a deeper understanding of what motivates firms to install solar power as a part of their CSR. Particularly, we investigate whether the decision to install solar power stems from the three main driving forces to engage in CSR presented by Benabou and Tirole (2009). Taking off in a frame of reference of economic theory and empirical research on CSR, we performed semi-structured interviews with nine Swedish firms with the aim to investigate what the main driving forces behind their decision to install solar panels where. Our hypothesis is drawn from a Benabou and Tirole (2009) paper structured around three main reasons to why firms engage in CSR: Doing well by doing good, Insider-initiated philanthropy and Delegated Philanthropy. Besides from our aim, we also wish to specifically gain an understanding on whether the implementation of the EU Directive on non-financial reporting in Sweden in 2017 was a motivator for our responding firms to install solar power as way of providing substance into their sustainability reports. Built on the existing theory that delegated philanthropy such as laws and regulations are a driving force for companies to engage in CSR, our hypothesis is that the implementation of the EU Directive had a positive effect on companies when deciding whether to install solar power. Our findings show that the driving forces behind the decision to install solar panels are of three types and that environmental reasons together with profitability dominates as the most important motivators, while demand from stakeholders stands out as a less important motivator out of the three. The EU Directive had no direct effect on the decision to install solar power for our respondents. This empirical study provides a contribution to the existing literature in two ways. Firstly, it adds to the current, literature on firms’ motives to engage in CSR. Our results support the theory that is presented in Benabou and Tirole (2009). Secondly, the study adds to the literature in the way that we specifically study why companies have chosen to install solar power systems. While there is extensive literature by scholars on the determinants and effects of CSR, there has been limited numbers of papers written about the investment in and installation of solar power by companies. / Kravet på företags ansvar för sina utsläpp och sin miljöpåverkan ökar i takt med samhällets medvetenhet om hur mänsklig aktivitet leder till klimatförändringar. Företag tar i allt större utsträckning ansvar för aspekter utanför deras affärsområde, ett samhällsansvar som går under benämningen Corporate Social Responsibility (CSR). Konsumenter, investerare och samarbetspartners inkluderar i allt större utsträckning hållbarhetsaspekter i sina val av företag, vilket gör CSR viktigt för ett företags överlevnad på marknaden. Samtidigt har en kombination av statliga styrmedel, innovationer och ökad konkurrens möjliggjort en ökning i andelen förnybar energi. Att ställa om till förnybar energi kan vara ett CSR-verktyg för företag. Ett sätt företag kan göra det på är genom att installera solcellssystem. Med denna uppsats syftar vi att undersöka vad drivkrafterna varit bakom företags beslut att installera solcellssystem som en del av deras CSR-arbete. Vi tar avstamp i ekonomisk teori om företagens roll på marknaden och hur vinstmaximering går i linje med ökat krav på samhällsansvar. Vi insamlar data genom semistrukturella intervjuer med nio svenska företag som har, eller är i processen att installera, solcellssystem på ett eller flera av sina tak. Vår huvudsakliga hypotes är baserad på Benabou och Tiroles (2009) teori om att drivkrafterna bakom CSR-engagemang härstammar från att öka lönsamheten, från intern filantropi eller från extern filantropi. Vår datainsamling visar att drivkrafterna bakom beslutet att skaffa solceller kan kategoriseras enligt Benabou och Tiroles (2009) tre CSR-motiv. Intern filantropi står ut som dominerande anledning hos våra respondenter, samtidigt som lönsamheten hos alla respondenter i varierande grad har varit en avgörande faktor. Vidare visade vårt resultat på att EU-direktivet om ickefinansiell rapportering inte påverkat respondenternas beslut att installera solcellssystem. Detta för att företagen antingen inte omfattas av direktivet, att installationen skedde innan direktivet trädde i kraft eller att de redan innan direktivet trädde i kraft ägnade sig åt ett omfattande hållbarhetsarbete. Med denna uppsats bidrar vi till befintlig litteratur på två sätt. För det första, till den omfattande mängd litteratur kring motiv bakom CSR. För det andra, bidrar vi med en inriktning på installation av solcellssystem specifikt, där litteraturen till dags dato är begränsad.

This report is going to investigate the possibility to save energy by converting a valve opening mechanism in a waste disposal system from a pneumatic system to an electric system. To power the system, which mainly consists of an electric actuator and a valve control module, a solar panel system was designed. The valve system was controlled by the lightweight messaging protocol MQTT. To be able to choose an electric actuator the needed force was measured and data regarding maximal stroke was taken from the data sheet of the existing setup. For developing an optimal solar panel system a program was written in Google Spreadsheet. The program takes input regarding power, cycles, solar panel system specifications and environmental factors. The output from the program is energy consumption for the system, specification for solar charger, solar panel setup and charge data. The result was that the solar panel system needed to consists of four 12 V VRLA batteries with a capacity of 90 Ah each and four solar panels with a rated power of 300 W each. The solar charger must be able to handle 900 W and provide an output current of 25,5 A to fulfil the demands. The new electric actuator will consume four times less energy than the old pneumatic actuator. Most of the energy savings are consequences of reduced energy consumption at idle of the system. A demonstarator was built to test the system. / Den här rapporten kommer att undersöka möjligheten att spara energi genom att konvertera ett ventilöppningsmekanism i ett avfallshanteringssystem från ett pneumatiskt system till ett elektriskt system. För att driva systemet, som främst består av en elektrisk aktuator och en ventil styrenhet, ska ett solcellssystem designas. Ventilsystemet ska styras med hjälp lättviktsmeddelandeprotokollet MQTT. För att kunna välja en aktuator mättes den behövda kraften och data angående maximal slaglängd togs från databladet på den nuvarande konstruktionen. För att utveckla ett optimalt solcellssystem skrevs ett program i Google Kalkylark. Programmet använder energi, cykler, solcellssystem och miljöfaktorer som indata. Som utdata ges energiförbrukning hos systemet, specifikation för solcellsregulator, solpaneler och laddningsdata. Resultatet var att det solcellssystem som behövs bestå av fyra 12 V VRLA batterier med en kapacitet på 90 Ah var och fyra solpaneler med en nominell effekt på 300 W vardera. Solcellssregulatorn behöver kunna hantera 900 W och generera en ström på 25,5 A. Den nya elektriska aktuatorn kommer förbruka fyra gånger så lite energi jämfört med den gamla pneumatiska aktuatorn. Den största delen av energibesparingarna är en konsekvens av minskad energiförbrukning av systemet i vila. En prototyp byggdes för att testa systemet.

With the growing energy consumption in the world today, the decreasing amount of fossil fuels and their negative impact on the environment, developments and greater use of renewable energy resources is crucial. One of the promising environmentally friendly energy resources is solar power. The technology for producing electricity from the use of solar cells is continuously developing and is growing on the market. The objective of this master thesis is to illustrate how solar panels can be integrated into a building’s design, and what value this gives to the building. The purpose is also to give an indication of whether an integrated solar panel installation is profitable, and what is required for more building developers to invest in solar power. A study on solar cells was conducted to gain knowledge of the different types of solar cells and systems and their possible integration into buildings. The study also included research on why solar cell installations are not more common today. Case Studies were also conducted on projects with integrated solar cells. This was done to gain an understanding of how solar panels can be used as design elements. The study was done as a systematic literature study through a qualitative method. City and site analyses were carried out as a first step in the design process. The analyses focused on the movements, green spaces, climates, functions and architectural character of the city and site. The analyses were done to attain an impression of the environment the building would be placed in, and its requisites. These analyses were followed by volume and solar studies to come up with a building design that would fulfill the requirements of the client, while creating good areas for placement of the solar panels. The master thesis resulted in a design proposal for a mixed-use building with integrated solar cells. The resulting two buildings are located in the outskirts of the city center of Linköping. The buildings are designed to interact with the surrounding buildings and the remaining city, while at the same time bringing something new and exciting to the mix. The buildings’ placement and height were decided by the combination of the movement of the sun over the plot, so as to create good areas for the solar panels, and the requisites of the site. The integrated solar panels are placed on the roofs and facades of the buildings. The possibilities of semitransparent solar cells in windows and glass railings is also examined. The solar panels on the roof consist of solar roof tiles and are placed on the east side of the north building’s roof and the west side of the south building’s roof. These tiles have matching roof tiles without solar cells inside, on the other side of the roofs, meaning that no difference can be seen between the two sides. The façade panels are placed to cover the entire protruding stairwells of the buildings. Panels are also placed on remaining parts of the south-east and south-west facing facades but are here placed in a pattern as though they are trickling down the walls. The panels are placed to avoid shade as shading of the panels reduces their effect. The solar cells are smooth, black, thin-film solar cells and the panels have matching glass panes that are placed were the design opted for panels, but the placement was not good out of a solar irradiation perspective. The results of the rough calculations on the project’s solar panel installation’s profitability shows that the investment would have a payback time of approximately 15 years. This, when counting in a government support of 1.2 million kroners and the reduced cost for the building cover material that the solar panels replace. The solar panels in the design proposal are not in standard sizes. Would they have been so the investment cost would have been lower and the payback time, according to the rough calculations, would be around 10 years. The produced electricity constitutes around 60 percent of the operational electricity for the buildings. If semitransparent solar cells are included the value goes up to 80 percent. Although the produced electricity does not cover the complete electricity needs of the buildings, it still reduces the amount of bought electricity. Electricity that would most likely not come from a renewable source. The conclusion is, therefore, that an integrated solar cell installation is economically profitable. The solar panels contribute both the aesthetics of the building and building functions, as well as electricity from a renewable source. Investing in a solar cell installation also sets a good example and will lead to more investors taking a chance on solar power. Getting more building developers to invest in solar cells systems can be done by increasing the, today lacking, knowledge of solar energy and solar cells, the process for designing and installing a solar cell system, as well as the laws regarding solar power and solar power investments. Another obstacle for solar power is the high costs of the installations. The prices on solar cells are, however, continuously dropping, because of the development in technology and the manufacturing process, as well as the growing number of manufacturers. To increase the speed of this process more building developers should invest in solar cells, as a higher demand will lead to more manufacturers, which will then lead to reduced prices. The government can also help by offering research support and for example tax subventions to make an investment in solar power seem more worthwhile.

Denna rapport redogör för ett projekt inom området industriell teknik och hållbarhet. Studien utreder möjligheten att tillämpa en förnyelsebar energikälla där solenergi skall utvinnas genom solceller. Energin som utvinns skall till en viss grad leda till energiförsörjning hos Rosendals Trädgård. Verksamhet har valts som ett hypotetiskt förslag på hur man kan anpassa, beräkna och implementera solceller. För att uppnå ett realistiskt förslag har företaget HP Solartech används som ett “verktyg” och teoretiskt stöd kring solcellstekniker och beräkningsmodeller. Syftet med detta projekt var att ta fram beslutsunderlag för Rosendal, med hjälp av att använda HP Solartechs simuleringsprogram för solcellsanläggningar. Resultatet visade att en solcellsanläggning på Rosendal skulle täcka 24% av den årliga energiförbrukningen och ge en kostnadsbesparing på SEK 160 900. / This report describes a project concerning the area within industrial technology and sustainability. The research investigates the possibility to apply a renewable energy source utilizing solar energy through solar cells. The energy that extracts shall, to a certain extent, be applied as an energy source to the establishment Rosendals Trädgård. Rosendals Trädgård was chosen as a hypothetical example of how an implementation of an organization can be successful. The company HP solartech was a leading hand during the study since they attain professional knowledge within this subject. In order to make the study accurate, HP solartech supported the data by sharing the ground theories about solar energy, the difficult calculations and the implementation of solar cells. With their guiding and support, valuable facts and results was attained. The aim to this project is to present a proposition to Rosendals Trädgråd with support from HP solartech. The result for Rosendal turned out to a production of solar energy that covers 24% of their current energy consumption and an economical saving of SEK 160 900 annually.