The aim of this thesis has been to investigate the technical and social potential for electric car charging as a flexibility resource in Uppsala. In addition, the user pattern has been examined, as well as the drivers’ motivation and obstacles contributing to flexibility. This has been done through quantitative and qualitative methods in the form of simulations and semi-structured interviews. The results show that the user pattern of the chargers and Uppsala city show a great similarity in form of two peaks. However, the peaks do not coincide, as they are separated by two and three hours, respectively. Furthermore, the public charging station occupancy turns out to be low, which is explained by the interviewees as the fact that the majority have their primary charging station at home. It is not important when charging takes place, only that it takes place. However, it is of great importance to always be able to charge. The drivers' motivation and impediments to assist with flexibility vary greatly in terms of the size and significance of the compensation. The results show that just over 2/5 of every charging session has flexibility potential, and that charging takes place for about half of the connected time. The largest proportion of flexibility potential lie within 30 min-1h followed by 1-2h respectively. Thus, with the possibility of shifting or pausing charge during that time. The greatest potential is obtained for 1,85 kW charging, largely due to an overrepresentation in the data set used for the simulations. A theoretical flexibility has been established based on the available energy data. However, to analyze in detail how car charging affects Uppsala's capacity shortage, access to high resolved power data is of great importance. To sum up, the overall results show that there are substantial preconditions for a technical and social potential for electric cars as a flexibility resource in Uppsala. Although, it requires well-developed incentives and aids to be realized, where end users assist with flexibility to the electricity grid.

In Uppsala, there has been grid congestion in the electricity grid because of thegrowing demand for electricity in the region over the past ten years. This study aimsto explore the possibilities of using V2G as a solution to this problem. V2G isimplemented as a type of energy resource using the electric car's battery to supplythe property with electricity. In this way, the power peaks created may be reduced.This report aims to examine three different scenarios. The scenarios are simulated inMATLAB. Each scenario has different values for the significant factors such as thebattery size, the number of electric cars parked, and the charge and discharge speeds.The first scenario reflects the situation today, while the other scenarios explorescenarios of future vehicle fleets. This study shows that V2G is a theoretically feasibleresource for peak-power shaving for commercial properties in the future.Furthermore, the result shows that even with today's battery sizes and levels ofelectric cars in the vehicle fleet V2G can theoretically be implemented successfully.Further discussions regarding the future implementation of V2G and what is requiredboth socially and financially are also addressed shortly.

To enable the transition to a fossil-free society and ongoing urbanization, where new establishments emerge in the heart of the society, the Swedish electricity system faces new challenges. Building a new powerline to meet the increased power demand is an expensive process, and in an existing grid, there isn’t always room to build new power lines. This leads to a capacity shortage at the local level, fundamentally due to the grid being undersized in areas where there are old power lines with lower rated current. To meet the increased power demand that electrification entails and simultaneously make capacity available for new establishments within the existing grid infrastructure, the potential of energy storage is being evaluated against the traditional solution of building new power lines. The purpose of the present work was therefore to investigate whether energy storage can be a potential solution to make capacity available for future establishments in an area where there is a capacity shortage. The energy storage solutions were evaluated from an economic, environmental, and power quality perspective and compared to building a new power line. This was done from the perspective of a grid company, where neither the market of frequency stability nor the electricity price market were included in the analysis. Based on the existing theory of energy storage, battery storage was chosen as the potential solution. To narrow the scope of the work, an area in Piteå Municipality was selected where a new establishment demands a power with drawal of 3 MW and is located midway between two existing grid lines. Using one year of operational data for the affected grid lines and calculations of their rated current, the performance of the battery storage was simulated, evaluating different battery sizes and energy contents (C-rate). Since the Electricity Act does not allow grid companies to own energy storage, the economic aspect was evaluated based on two different cases of battery rental. The goal is to maintain redundancy with the adjacent grid line with the additional power with drawal of 3 MW, to manage a potential outage without extensive consequences for subscribers. The results of the calculations and simulations show that the current grid line can handle the extra 3 MW requested. However, the battery storage does not relieve the grid sufficiently to prevent exceedingthe maximum capacity of the grid during high loads while maintaining redundancy with the interconnected grid line. The battery storage needs to be larger than 3 MW to relieve the grid as required, which is not economically justifiable. Depending on the rental conditions of the battery storage and which revenues are considered, the profitability of battery storage varies, but with a battery size over 1 MW, regardless of rental conditions, it is not economically justifiable compared to a new power line, which has a significantly longer technical lifespan. For battery storage to be useful in the grid and make capacity available, the grid must have spare capacity. The results also show that the relationship between the size of the establishment and the size ofthe battery storage is not one-to-one, instead, the energy content of the battery storage must be significantly larger to cut the power peaks. An energy content of two times the power, for example, 1 MW and2 MWh, is required for the battery to be advantageous and generate load savings on the grid. However, the battery storage can still relieve the grid to some extent by helping to distribute the current load more evenly, which means that the rated current, which is the limiting factor for short power line lengths, is not exceeded as early.

Region Uppsala, who are responsible for the public transport in Uppsala county, are currently building a new city bus depot. Due to capacity shortage in the transmission grid to Uppsala, the operation of the new bus depot must be adapted to a limited power output. In addition to this, the city of Uppsala aims to introduce the first electrical buses by 2021. The purpose of this study was to investigate how electrical buses of different penetration level will affect the power demand at the new city bus depot. The results showed that the current power limitation was already exceeded by 200 kW if 12 electrical buses were to be introduced. Therefore, different technical solutions were evaluated in terms of increasing the penetration level of electrical buses. These solutions were evaluated by a life cycle cost analysis. The cheapest solution was to connect the city bus depot with the regional bus depot. This is possible because the grid connection to the regional bus depot is oversized, compared to its load. However, this solution does not solve the general problem of capacity-shortage in Uppsala and the legality of it must be analyzed further. Two other solutions that were investigated were a local battery storage and a gas engine coupled with a generator at the depot. None of the solutions could solve the power problem at the depot on its own. For a scenario with more than 40 electrical buses, the different technical solutions that were investigated must be combined.

I samband med en ökad tillväxt och elektrifiering av samhället där andelen grön intermittent elkraft ökar och kärnkraften avvecklas kan efterfrågan på el vid topplasttimmar bli svårhanterliga för elnätsägare. Med en ökad risk för både effekt- och kapacitetsbrist i södra Sverige och långa handläggningstider vid utbyggnation av stam- och regionnät behöver nya åtgärder för att upprätthålla stabila elnät undersökas och analyseras. Energimyndigheten anser att bostadssektorn spelar en viktig roll där både energi- och resurseffektivisering samt en ökad kunskap kring elanvändning är nödvändigt för att uppnå flera samhällsmål. Rapporten ämnar därmed att undersöka och belysa elbehovet för bostäder med olika uppvärmningssystem i Halmstad samt ta reda på hur en effekttariff kan påverka bostäders ekonomiska situation jämfört med dagens säkringstariff. Studien utförs tillsammans med Halmstad Energi och Miljö Nät som driver elnätet i Halmstads tätort med omnejd, varav rapportens undersökta bostäder ligger inom koncessionsområdet. Resultatet påvisar en markant skillnad i elanvändning mellan bostäderna, speciellt under kalla årstider, där valet av uppvärmningssystem kan påverka effektbehovet inom koncessionsområdet avsevärt samt reducera effekttoppar. Resultatet belyser även effekttariffens inverkan på bostädernas månadskostnad där tariffen gynnar bostäder med ett lågt elbehov samt ger ekonomiska incitament för lastförflyttning under höglastperioder. / With an increasing share of green intermittent power and the upcoming discontinuance of nuclear reactors the electricity demand of today’s Swedish society could become hard to purvey for net grid owners. When the risk for capacity and power shortages are growing and the proceedings of new powerlines are long, new strategies are needed to keep stability in the grids. According to the Swedish energy authority the residential sector plays a major part where both energy- and resource efficiency, together with increased knowledge of energy usage, is necessary to reach several societal goals. Therefore, this report aims to investigate the difference in power demand between residential buildings in Halmstad based on their heating systems and the economic effects of a power tariff implementation. The study is carried out together with Halmstad Energi och Miljö Nät, who operates the electricity grid in Halmstad’s urban areas and provides information of their customers for the aim of this study. The results show a significant difference in power demand between residential buildings, where the method of heating could have a major effect on the power grids capacity and be used as means for power peak reductions. An implementation of power tariffs favors residential buildings with a low power demand, where high demands can lead to expensive bills and force owners to reallocate their demands.

This study has examined what services grid-connected energy storage systems can provide to the electricity grid in Sweden. In particular, energy storages in the form of batteries have been examined. This has been done by studying existing literature and current installations of grid-connected batteries. A total of 13 different services were identified: arbitrage, capacity firming, curtailment minimization, electric supply capacity, black start, frequency regulation, voltage support, transmission and distribution congestion relief, reduced transmission grid costs, increase of self consumption, end-consumer power quality, time-of-use bill management and backup power. Furthermore, a grid-connected battery storage system that will be installed by Vattenfall was modelled and simulated in this paper. The results showed that the battery storage system can mitigate congestion in the transmission grid, as well as providing the grid with frequency regulation. This can generate a revenue of 3 million SEK annually.

The city of Uppsala is suffering from power shortage, which is creating issues for Region Uppsala, which manages the new city bus depot. Gamla Uppsala Buss (GUB), the operator of the city busses, has bought 12 electrical busses and is planning to increase that number up to 60, which is a political goal. Charging of the electrical busses occurs mostly in the nights, but also during lunch time. In this thesis, scenarios of how different number of buses (12, 36 and 60) relates to the power subscription limit at the depot is studied. The study was made through interviews with industry experts and by creating different scenarios in an Excel-model which was produced in this work. One main conclusion from the interview study was that the regulation control of all the technical components of the system, and foremost the regulation control of the charging of the busses, is a vital component to handle the charging properly. Optimal regulation control requires accurate planning and advanced calculations which relies upon access of data, i.e., charging cycles, battery range and electric energy consumption. The simulations in the Excel-model showed that the bus depot could handle 12 electrical buses with the available power subscription that is today. For 36 or 60 electrical busses additional power had to be added behind-the-meter, which could be obtained with energy storage (batteries), a biogas engine linked to a generator or a combination of those two. The simulations showed that either an energy storage or a biogas engine could compensate for the lack of power, with reasonable proportions. The two technical solutions could also be combined in infinite ways, depending on the goal of Region Uppsala, to fulfill the task. The technical solution that is most feasible for Region Uppsala depends on their priorities. The economics of the solution will of course be a big factor, which has not been included in this work. Another feasible priority could be to choose a technical solution that creates utility for the power system of Uppsala, i.e., mitigating power shortage, with a solution that has a high selfproduction of electric energy and a power consumption profile of the bus depot that is inverted to the rest of the city’s.

I denna rapport undersöks om det föreligger ett behov av anpassningar inom energisystemet för att möjliggöra utvecklingen av eldrivna lastbilar i Sverige och mer specifikt Stockholm. En ansats till att projektera utvecklingen av eldrivna lastbilar görs och genom en kvalitativ litteraturstudie samt intervjuer med aktörer som representerar Scania, Volvo, Ellevio, EoN, Powercircle, Forum för smarta elnät, KTH, Energimarknadsinspektionen och BIL Sweden, och anpassningar som skulle kunna utgöra lösningar till dessa identifieras inom kategorierna: ‘’ökad tillgänglig kapacitet’’, ‘’förbättrad planering’’, ‘’d irekt reglerande åtgärder samt ekonomiska incitament’’ och ‘’p olitiska beslut på kommun- samt regional nivå med syfte att öka elektrifieringen av lastbilar ’’. Slutligen görs en jämförelse av anpassningarna med avseende på tillgänglighet och implementeringstid, lagliga hinder, kostnadseffektivitet, miljöpåverkan, replikerbarhet samt intressekonflikter. Utifrån resultatet dras slutsatserna att elektrifieringen kommer möjliggöras av flera lösningar i varierande grad men att anpassningar som inbegriper ökad flexibilitet inom elsystemet, för motverkandet av kapacitetsbrist inom elnätet, sannolikt kommer ingå. Vidare konkluderas att flera av de identifierade anpassningarna begränsas av legislativa- och politiska beslut och förändringar som gör dess bidragande till elektrifieringen av lastbilar svårkvantifierad. Resultaten bör därför betraktas som indikativa. / This study investigates the need for adaptations within the energy system of Stockholm, Sweden in order to improve the prerequisites for the development of electrical trucks. An attempt to project the development of electrical trucks is executed and by the use of a qualitative literature study as well as interviews with representatives for Scania, Volvo, Ellevio, EoN, Powercircle, Swedish Smartgrid, KTH, the Swedish Energy Markets Inspectorate and BIL Sweden, possible adaptations are identified within the categories: ‘’increased available capacity’’, ‘’improved planning’’, ‘’direct regulations and financial incentives’’ aswell ‘’political decisions on municipal and regional level with the aim to increase the electrification of trucks’’. Finally a comparison with respect to availability and implementation, legislation, cost, environmental impact, replicability and conflicts of interest is made between the identified adaptations. Based on the investigation it is concluded that several adaptations, to varying degrees, will play a part in enabling the electrification. It is furthermore concluded that adaptations that involve increasing the flexibility within the electricity system will play a prominent role as solutions. Several of the adaptations are limited in their implementation as they are dependent on the conceiving of legislative and political decisions. This provides uncertainty in terms of projecting their contribution to the electrification of trucks and the results are to be taken as indicative rather than absolute.

På grund av den rådande energiomställningen flockar både företag och privatpersoner till mer effektiva och gröna energislag. I många fall är dessa via elnätet, vilket gör det lämpligt att se över hur ett lokalnät påverkas av en sådan ökning av effekt samt om det finns kapacitetsbrist. Syftet är att utreda mängen nya elbilsladdare till 2030, samt undersöka om det finns kapacitetsbrist vid både normalt kopplingsläge samt två reservkopplingslägen. Det ska även undersökas om det finns nyckeltal för olika dimensioneringskriterier. De metoder som används för att uppskatta en framtida toppeffekt i nätet är olika. Den ena antar en homogen ökning samtidigt som den andra baserar sin väntade ökning på antal hushåll, parkeringsplatser och verksamheter i området runtomkring en nätstation. Det blir ganska stor spridning, samt olika slags resultat för de olika kopplingslägena. Utifrån uppskattningarna som gjordes, simulerades den nya högsta effekten för de olika scenarierna och kopplingslägena och därefter beräknades belastningen i kablarna för dessa. Simuleringar visade att det finns kablar i alla scenarierna som inte håller upp till företagets egna mål angående belastning i kablarna. I reservkopplingsläget klarade många kablar heller inte av den högsta strömmen som kan förväntas under högsta lasttimmen utifrån databladet för kablarna. När topplasten ökar, ökar även antalet kablar som blir överbelastade, i scenario 1 blev det många fler jämfört med nuläget och scenario 2. För de normala kopplingsläget gick det nästan alltid att byta ut till grövre kablar för hålla sig under den angivna belastningsgraden av 50$\%$ eller precis ovanför.  För reservkopplingslägena blir det svårare då kablarna måste ha en belastningsgrad under $100\%$ för att inte överlastskydden ska slå till. Där hittades det att byta till grövre kablar inte alltid var bäst då högsta strömmen var högre än den grövsta kabeln som används. Denna högsta strömmen verkar bero på att en slinga ska reservmata fler än en annan slinga. Det kan då vara lämpligt att bygga fler reservslingor som då kan underlätta vid reservmatningsläget. / Given the roaring energy transition, both people and companies want to be ahead of the curve and change to more energy efficient and green energy con- sumption. In most cases these renewable energy have to use the electrical grid, which is why this study focuses on the distribution network in a local electrical grid regarding its capacity. The goal is to estimate and investigate the amount of charging points for electrical vehicles in regards to the available capacity in the network. This is to be done in three different network configurations, which is then to conclude in dimensioning criterias. The three methods used to estimate the increase in top load in the local electrical grid are different. Two of the assumes a linear increase in the top load of every transformer, while the other one is based on the area which the sub- station is placed and estimates according to households, businesses and parking places. Where the top load increase differes between the different scenarios. With the estimations at hand, the different network configurations were simulated and subsquently calculated the load in the cables for the different scenarios. These simulations pointed out that there are cables in every scenario that are not up to par with the companys goal of limiting the load in the network configuration that is normally used. Aswell as not up to par with the cable data sheet in the reserve configuration. As the top load increase the amount of cable above the threshold increased, especially in scenario 1 for the normal configura- tion mode. In most cases in the normal configuration mode changing the cable to a 240mm2 cable would solve the problem. For the reserve configuration mode it was not always that simple, mostly because one trail of cable sometimes back up several other trails. Resulting in a bottle neck between the trails, some of these are not fully up to par, and some of them even have a higher maximum current than what the cables that are used can handle. Which meant that so- mething other than changing cable would be prefered, the best option seems to be increasing the amount of trail that can back up in the reserve configuration

This master thesis has examined how two of the heat pumps at Norrenergi, Solnaverket, can be converted to steam driven heat pumps. The heat pumps are driven by electrical motors today and this thesis has investigated the technical and economical aspects of replacing them with steam turbines and also installing a pellet boiler. The purpose with this project is to lower the costs for the heat pumps which varies with the electricity price, where the electricity taxes represent about 40-60 % of the total electricity cost. In addition, Norrenergi is one of the largest electricity consumers in Stockholm. This, combined with the prevailing capacity shortage in Stockholm makes it important to examine another alternative than electricity for the heat pumps. Capacity shortage means that electricity can't be transmitted into the city during periods with high electricity demand. The results of this master thesis show that the costs reduces on a system level when two steam driven heat pumps are installed compared to the electrity driven heat pumps. All district heating plants in Stockholm, including Söderenergi's, Norrenergi's and Stockholm Exergi's plants, have been involved while examining the costs in this study. Despite the cost reduction the investment calculation shows that the investment is not profitable for a low or average electrity price. For a high electricity price the investment seems to be profitable, but this is not considered enough for the investment to be recommend since future electricty prices are hard to predict. On the other hand there might be other aspects than economical to invest in this type of district heating plant, for example from a sustainability perspective. / Norrenergi är ett fjärrvärme- och fjärrkylabolag i Stockholm som bland annat producerar värme via energiåtervinning i en VP-anläggning i Solnaverket. Värmepumparna har en total värmeeffekt på 100 MW och drivs av elektricitet samt spillvatten från Bromma reningsverk. Kostnaden för att producera fjärrvärme via värmepumpar varierar med elpriset där en betydande faktor är elskatten. Elskatten utgör ungefär 40–60 % av den totala elkostnaden för VP-anläggningen i Solnaverket. Utöver de höga kostnaderna för att driva VP-anläggningen råder en så kallad kapacitetsbrist i Stockholm vilket bland annat grundar sig i att staden växt i en snabbare takt än utbyggnaden av stamnätet. På grund av ovan nämnda orsaker är det intressant att undersöka alternativa lösningar för hur den eldrivna VP-anläggningen kan producera fjärrvärme, dels för att minska kostnader för elektricitet men också för att bidra till en samhällsnytta genom att minska effektuttaget på elnätet. Detta examensarbete ämnar därför undersöka hur två av värmepumparna i Solnaverket kan omvandlas från eldrift till mekanisk ångdrift via ångturbiner, där ångturbinerna i sin tur drivs av ånga från en pelletspanna. Därtill undersöks systemdriftsnyttan, där även Stockholm Exergis och Söderenergis anläggningar beaktas, samt lönsamheten för att konvertera två av värmepumparna till ångdrift. Resultatet visar att systemdriftsnyttan är positiv oavsett elprisprofil vilket beror på att kostnaderna på systemnivå minskar när ångdriven VP-anläggning implementeras i Solnaverket. Trots den positiva systemdriftsnyttan visar dock investeringskalkylen att denna investering endast är lönsam vid ett högt elpris. Det beror bland annat på att den positiva systemdriftsnyttan inte är tillräckligt hög (vid låg och medelelpris) för att uppnå ett tillräckligt högt nuvärde med given kalkylränta och ekonomisk livslängd, i jämförelse med grundinvesteringskostnaderna. Den låga lönsamheten beror dessutom på att Stockholm Exergi ska bygga ett nytt avfallskraftvärmeverk i Lövsta som har billigare produktionskostnader än den ångdrivna VP-anläggningen. Det är svårt att förutspå elprisets utveckling framöver och variationerna i elpris under året förväntas öka, därför är det rekommenderat att denna investeringen inte genomförs eftersom den beror så pass mycket av elpriset. Det kan dock finnas andra aspekter än ekonomiska i att investera i en ångdriven VP-anläggning. Till exempel ur ett hållbarhetsperspektiv då belastningen på elnätet minskar när de eldrivna VP:arna konverteras till ångdrift.