The world is experiencing increasing energy usage owing to environmental impacts suchas climate change, Ozone layer depletion, and global warming. Energy usage is primarily categorized into transport, industrial, residential, and service sectors, with the transportation and industrial sectors taking up a considerable chunk of the energy use; Buildings partly determine the use of energy globally. This review presents a critical analysis of energy demand and uses in the building sector considering the energy optimization for The Church of Jesus Christ of Latter-day Saints in Trollhättan, including the local energy requirements. The modelling software IDA-ICE isused to conduct simulations for different scenarios. The IDA-ICE software links the actual building images with the isometric views done on a computer. The energy balance of buildings is considered with respect to the three methods for heat transfer, the U-value,ventilation, heating load, and cooling load. The study results show that the building relieson electricity and fuel for its energy supply and that fuel consumption takes the highest share, 60 %. Retrofit 1 (where the oil and electric boilers are replaced by geothermal heat pump with COP 4 for heating and domestic hot water), Retrofit 2 (which keeps changes from Retrofit_1 and where a new AHU with a VAV system replaces the existing two AHUs), and Retrofit 3 (which keeps changes from Retrofit_2 and only connects the heating system to district heating) are designed as part of the findings to understand the variation sin comfort reference, supplied Energy, used Energy, utilized Energy, auxiliary Energy, and the Energy of all zones during heating and cooling. The model results indicate that Retrofit2 demonstrates better results than the other two since it has a higher energy-saving capacity. The energy reduction for Retrofit model 1 is about 33.4 %, while Retrofit model 2 has 55% and model 3 has 33%, significantly decreasing the associated costs. The LCC analysis shows payback for the first model 6.73 years with an investment cost of 700 000 SEK, the second model has 5.84 with 1 million SEK investment, and the third model has 3.4 years with 350 000 SEK.

År 2017 stod sektorn bostäder och service för 39 % av Sveriges totala slutliga energianvändning. Det behövs en minskad energianvändning och en energitillförsel med låg miljöpåverkan för att klara miljökvalitetsmålen på längre sikt. Energi för uppvärmning av lokaler och byggnader står för 74% av den totala energianvändningen i bygg- och fastighetssektorn. Passivhus är en byggnad som är mer isolerad och tätare än en vanlig byggnad. Kraven är höga på material, konstruktion och genomförande för att uppnå så låg energianvändning som möjligt. Syftet med detta projekt är att studera förändringar i BBR28:s nya nybyggnadskrav och kraven för certifiering av passivhus FEBY18 samt att undersöka hur BBR:s och FEBY:s nya krav påverkar passivhus i fråga om kostnaden vid ett respektive två plan och olika typer av vanliga värmekällor. Målet är att beräkna och jämföra bygg- och uppvärmningskostnader för referensvillor som uppnår BBR:s nybyggnadskrav respektive villor som uppnår FEBY:s nya passivhuskrav. Villorna kommer också jämföras mellan fjärrvärme respektive luft/vattenvärmepump som uppvärmningskälla samt skillnaderna mellan en- respektive tvåplansvilla. För att beräkna lönsamheten på passivhus kommer det att utföras tre olika fall mellan konventionella hus och passivhus. Fallen är en enplansvilla, en tvåplansvilla som båda uppvärms med fjärrvärme och en enplansvilla med luft/vattenvärmepump. De tre fallen anpassas till att klara både BBR:s krav och FEBY:s krav för att få fram hur mycket kostnaden skiljer mellan konventionella hus och passivhus. VIP-Energy kommer användas för att beräkna energiförbrukningskostnaderna på de olika fallen. Sedan används Bidcon för att beräkna material- och arbetskostnaderna. Det kommer utföras en LCC-kalkyl för att få fram hur lönsamt det är att bygga passivhus jämfört med konventionella hus. När det gäller lönsamheten på passivhus så har BBR:s och FEBY:s nya krav inte påverkat mycket förutom FEBY:s nya krav för ej eluppvärmda byggnader där lönsamheten minskar. Då FEBY-kraven inte förändrats mycket för eluppvärmda byggnader kan man säga att certifieringen inte heller har det men för ej eluppvärmda så har certifieringen blivit lättare. Enligt studien var det lättare att nå kraven med en byggnad som var elvärmd för både BBR och FEBY. FEBY-villan och BBR-villan kom långt under kraven när de hade värmepump som uppvärmningssätt. Studien visade också att en enplansvilla och tvåplansvilla inte skilde mycket gällande energivärden och gör det därför inte lättare att bygga verken passivhus eller konventionella hus. Dock blir det lite billigare att bygga passivhus med två plan.

Byggbranschen ställs nu inför en stor förändring. EU-kommissionen har bestämt att det ska byggas nära-noll energibyggnader från och med 31 december 2020. Boverket har försökt anpassa reglerna utifrån svenskt byggande och försökt årligen sätta hårdare krav gällande energihushållning. Ett sätt att minska energianvändningen är genom att bygga passivhus. Byggherrar är de som beställer byggnader och bestämmer i hög grad byggkonstruktionen av sina byggnader. Efter hårdare energikrav från myndigheterna behöver byggherrarna reda ut alternativ som kan gynna dem i framtiden både ekonomiskt och miljömässigt. Ekonomin och kostnader, men nu även miljöpåverkan, har stor påverkan för val av byggnad. Passivhus är en byggnad som visat sig ha lägre livscykelkostnader och lägre energianvändning jämfört med konventionella hus. Det genomfördes en enkätundersökning där målet var att ta reda på vad byggherrarna tänker och gör vid nyproduktion, andelen producerade typer av byggnader och organisationernas preferenser gällande nyproducerade byggnader. I enkätundersökningen har det ingått byggherrar som arbetade i kommunala lokalförvaltningar, allmännyttiga bostadsbolag, privata, regionala och statliga fastighetsbolag. Majoriteten av respondenterna för de olika byggherrarna anser att sina organisationer föredrar en högre produktionskostnad som medför lägre driftkostnader. De byggherrar som inte bygger passivhus (80 %) förklarar att det är bland annat på grund av höga nybyggnadskostnader, ny och ovan teknik och höga krav på byggnaden. Men en stor del av dessa organisationer kan tänka sig bygga passivhus i framtiden. Passivhus är dyrare att uppföra men har lägre driftkostnader och har i en stor majoritet av fall lägre livscykelkostnader. Genom lägre energianvändning och certifierat passivhus, är konceptet även bättre miljömässigt än för konventionella hus. Byggherrarna väljer dock att mest uppföra konventionella hus. Det används livscykelanalys i hög grad, som beräknar en byggnads totala miljöpåverkan. Verktyget leder dock mer till att alternativet ”typ av miljöcertifierad byggnad” väljs före passivhus. Svaren på enkätfrågorna skulle gynna nyproduktion av passivhus då de flesta byggherrarna har en hög prioritering av både miljöpåverkan och livscykelkostnader. Passivhus är dock minst lika komplicerad och omfattande att bygga än konventionella hus och de flesta byggherreorganisationerna ger en rad olika orsaker till att de inte bygger passivhus. Beställare av färdiga passivhusprojekt har dock haft positiva kommentarer om sina passivhus. / The construction industry is now facing a major change. The European commission has decided that near-zero buildings will be built from 31 December 2020 onwards. Boverket has tried to adapt the rules based on Swedish construction and has annually tried to set stricter requirements regarding energy management. One way to reduce energy use is by building passive houses. Building customers are those who order buildings and largely determine the construction design of their buildings. Following stricter requirements from the authorities, building customers need to sort out alternatives that can benefit them in the future, both economically and environmentally. The economy and costs, but now also the environmental impact, have a major impact on the choice of building. A survey was conducted where the purpose was to find out what the building customers think and do in construction of new buildings, the proportion of types of buildings produced and the organizations preferences regarding new buildings. The survey included building-customers that worked in municipal local administrations, public housing companies, private- and state real estate companies and in the region. Most of the respondents for the various building customers believe that their organization prefer a higher production cost which entails lower operating costs. The building customers who do not build passive houses (80%) explain that this is partly due to high production costs, new technology and high demands on the building. But a large amount of these organizations can imagine building passive houses in the future. Passive houses are more expensive to build but have lower operating costs and in a large majority of cases also lower life cycle costs. Through lower energy consumption and certified passive houses, the concept is also better environmentally than for conventional houses. Life cycle analysis is used to a great extent, which calculates a building’s total environmental impact. However, the tool leads more to the option “type of environmentally certified building” being chosen before passive houses. Building customers’ answers to the questions do not show up in the buildings that are erected. The answer alternatives seem to favor new construction of passive houses. However, passive houses are at least as complicated and extensive to build as conventional buildings and most of the building customers organizations give several different reasons of why passive houses are not built. Clients of completed passive house projects have, however, had positive comments about their passive houses.

For a long time, frames have been built with traditional materials such as concrete and wood but there are newer, less tested alternatives. Posi-Joist is a new kind of hybrid beam which means that it consists of different materials that work together to form a stronger frame. Posi is a collective name for the different parts of the beam. Because Posi-Joist is a new beam, it hasn’t been tested as much as the more traditional materials. The purpose of this report is to investigate if Posi-Joist is an acceptable frame to use on larger constructions since it hasn't been investigated before. In order to investigate this, a hybrid frame consisting of Posi-Joist beams will be compared to a concrete and a wooden frame. When choosing a material there are different parameters that matter. The different materials will demand different spans, have different environmental impact, and have different costs. To investigate which frame is the optimal choice, different software will be used. Autodesk Revit will primarily be used to draw the frames’ different designs. Frame Analysis and FEM-Design will be used to perform calculations on the strength of the frames. One Click LCA will be used to obtain LCC and LCA. The wooden frame was the most expensive since the concrete frame’s price was just 40 % of the wooden frame's total cost. The hybrid frame’s price was 52,4 % of the wooden frame’s price and was therefore more expensive than the concrete frame but cheaper than the wooden frame. The wooden frame had less environmental impact since it emits 11,2 % of the concrete frame’s emissions. The hybrid frame emits 90 % of the concrete’s total emissions. The hybrid frame can manage the largest spans. The conclusion is that the concrete frame is the best option when it comes to design and price but has the most environmental impact. The wooden frame had the least environmental impact but could not manage compatible spans. The hybrid frame could manage the largest spans but was neither the worst nor the best in any of the other categories.

The basic mixture of lightweight cellular concrete (LCC) consists of cement, water, and a stable foaming agent. It is generally classified as having a density of less than 50 pounds per cubic foot (pcf), which is less than both traditional concrete and backfill materials. LCC has gained popularity in construction due to its lightweight, self-leveling, and ease of production and placement. These characteristics have made LCC a popular lightweight backfill material for mechanically stabilized earth (MSE) walls. However, there has been relatively little research on the large-scale behavior of LCC as a MSE backfill. Therefore, large-scale test results defining failure mechanisms and the strength criteria of reinforced LCC are extremely valuable. In this study, a three walled test box (10 ft wide x 12 ft long x 10 ft high) was constructed to contain the LCC. Two 5 ft tall x 10 ft wide MSE wall segments were poured and cured, before being placed as the fourth wall of the test box. The test box was built with a steel reaction frame to reduce lateral deflections during testing of the LCC that was not in the direction of the MSE wall, thus creating a two-dimensional or pseudo "plane strain" geometry. The box was filled with four lifts of Class II LCC 2.5 feet thick with ribbed-strip reinforcements at the center of each lift. After the LCC was cured, two static load tests were performed by applying surcharge to the surface of the LCC using six hydraulic jacks. The static load tests compared the LCC behavior of an MSE wall in comparison with unreinforced LCC without MSE wall panels. Multiple forms of instrumentation were used to understand the behavior of the LCC during surcharge loading. The instrumentation also helped to characterize the strength criteria for LCC based on failure in the large-scale and laboratory testing. This was done to determine the failure mechanism for the MSE wall retaining system with ribbed-strip reinforced LCC backfill. Data was gathered primarily through lateral wall pressures, lateral wall deflections, and forces induced on the ribbed-strip reinforcements. The test results show that an MSE wall with LCC backfill can withstand significant surcharge loading with limited axial and lateral deformations. However, failure occurred at surcharge pressures of about 60% of the unconfined compressive strength. The use of a retaining system significantly increased the failure loads and produced a more ductile failure mode than Class II LCC with a free-face. The active pressures observed are similar to a granular material with a friction angle (ϕ) of 34°, Ka=0.28, and a cohesion of 700 to 1600 psf for Class II LCC. Likewise, failure of the free-face occurred at a value predicted by Rankine theory with ϕ = 34° and c = 1600 psf.

No description available.

Lightweight cellular concrete (LCC) is a cement, water, and air entrained mixture that consists of 25-80% voids. The air voids reduce the material strength but also decrease the material weight. Due to its lightweight properties LCC is an attractive alternative to soil backfill for retained structures, such as mechanically stabilized earth (MSE) walls. Although LCC is widely used behind MSE walls, limited information exists regarding the pullout strength of MSE wall reinforcements in LCC backfill. This research attempts to fill the knowledge gap through performing pullout tests on welded wire and ribbed strip reinforcements in MSE walls to determine the pullout friction coefficient (F*), reinforcement pullout behavior, and LCC properties. A large-scale test box (10 feet wide x 12 feet long x 10 feet high) supported by a steel resisting frame, was constructed, and filled with LCC backfill. Both the west and east MSE wall faces consisted of concrete walls. The west wall was supported by 16 ribbed strip reinforcements, while the east wall was supported by nine short, welded wire reinforcements. After backfilling the MSE wall, pullout tests were performed of the 12 ribbed strip reinforcements and all nine welded wire reinforcements. To determine different pullout friction coefficients (F*), different surcharge loads were applied through LCC self-weight, concrete reaction beams, and hydraulic jacks at the top of backfill. After performing the pullout tests on the large-scale test box, additional pullout tests were performed in two smaller (10 feet wide x 6 feet deep x 30 in. tall) MSE walls, each containing four ribbed strip reinforcements to determine the F* of ribbed strip reinforcements at moderate surcharge pressures. Results from these tests produced F* recommendations for ribbed strip and welded wire reinforcements. Additionally, a total of 130 LCC cylinder specimens were used to identify LCC material properties. Results of these tests show that the unconfined compressive strength of LCC is greatly dependent on the cast and cured unit weight, as well as the sample maturity. Comparing the UCS results to other work reveals a wide variation of UCS versus cured density, even though the same ASTM standard was applied for all tests. An equation for the secant modulus of LCC was created using UCS data from this thesis and other research conducted at Brigham Young University (BYU). Direct shear tests were also conducted on LCC cylinders cut to fit the confinement of a direct shear machine. The direct shear test results from this thesis agree with other research conducted at BYU.

In Sweden, the long-term climate goal is to achieve a net zero emission of greenhouse gases by 2045. At the same time, today the Swedish construction and property industry accounts for 21 percent of all greenhouse gas emissions, and the use of more climate-friendly materials can be part of the solution. The aim of the study is to analyze the climate impact and costs from a nine-floor building, where four different frame systems are compared. The nine-floor building is of a normal concrete frame with load-bearing steel columns in the outer walls. This building will then be compared against if the building was made of green climate-compensated concrete. As well as two hybrid solutions where the top three floors are dimensioned to a wooden frame and six floors in gray and green concrete below. In order to analyze the climate impact and costs, a life cycle analysis (LCA) and a life cycle cost analysis (LCC) will be carried out using the One Click LCA tool. In the life cycle analysis, the stages (A1-A5) will be studied and in the life cycle cost analysis the material costs (A1-A3) will be studied. The result from the life cycle analysis shows that the hybrid building with wood and green concrete has the lowest climate impact in terms of emissions of carbon dioxide equivalents (CO2e), followed by the building in green concrete. The result also shows that the hybrid building with wood and green concrete has approximately 43% lower climate impact compared to the gray concrete building which had the largest. The life cycle cost analysis shows that the gray concrete building has the lowest material costs, while the hybrid building with wood and green concrete has the highest. The conclusions of the study are that dimensioning a wooden frame meant thicker building parts compared to a concrete frame, which resulted in a smaller living area. But the hybrid buildings with three floors with a wooden frame, on the other hand, had a significantly smaller climate impact compared to the respective concrete building.

Vid bestämmelse av vilket värme- och kylsystem som ska användas i fastigheter så finns det flertalet aspekter som går att ta hänsyn till. Tidigare har det varit högt fokus på energi och ekonomi, men med ökat fokus på hållbarhet och miljön både globalt och i Sverige har det blivit allt mer viktigt att hitta robusta lösningar som presterar inom samtliga av dessa områden. Helenius Ingenjörsbyrå som är installationskonsulter inom VVS-, miljö-, och energiområdet vill ligga i framkant när det kommer till energi och miljö. I samband med högre krav på hållbarhet och miljö är det av intresse för Helenius att se hur konventionella värme- och kylsystem presterar när de ställs inför energiprestanda, klimatpåverkan, ekonomi och återbruk. Utöver detta, även se hur resultatet för systemens prestanda påverkas av den geografiska placeringen genom att utreda dessa områden på lokal nivå (i Uppsala) och på generell nivå. Generell nivå motsvarar ett medelvärde för Sverige. Detta examensarbete har därmed tagit fram en arbetsmetodik för att utreda dessa områden och lämpliga system för ändamålet. Ändamålet i detta arbete handlar om att förse värme och kyla till en kontorsfastighet med tillhörande verksamheter där det finns en konstant kyllast över året. De fyra systemuppställningar som togs fram och utreddes i arbetet var: kylmaskin med värmeåtervinning från kondensorvärmen och separat fjärrvärmesystem (Modell 1). Andra uppställningen var kylmaskin med fjärrvärme och ingen möjlighet till värmeåtervinning (Modell 2). System tre var fjärrkyla och fjärrvärme (Modell 3) och system fyra borrhålslager som utnyttjar frikyla och bergvärmepumpar (Modell 4). Resultatet visar att Modell 4 var mest fördelaktigt för total köpt energi hos konsument både vid utredning lokalt och generellt. Den utredda EROI (Energy Return On Investment) visade på fördel hos Modell 3 både lokalt och generellt. Lägst klimatpåverkan i form av totalt utsläppta koldioxidekvivalenter från livscykelanalysen hade Modell 4 när det utreddes på lokal nivå, i Uppsala. Generellt i Sverige så var det istället Modell 1 som hade lägst klimatpåverkan. Systemet med lägst livscykelkostnad var Modell 1 när det utreddes lokalt för Uppsala, och i det generella fallet hade Modell 3 lägst livscykelkostnad. Kostnadsfördelningen mellan systemen visar att Modell 4 innehar en större grundinvestering men var därefter mer oberoende av marknadens energipriser, underhåll- och driftkostnader. De andra systemen hade lägre investeringskostnader och lägger större delen av livscykelkostnaden på energi-, drift- och underhållskostnader. Det framgick också att Modell 4 var den uppställning som var minst känslig mot ändringar i energipriser, vilket kan vara en säkerhetsfaktor för investeringar över lång tid. Arbetet utredde återbrukspotentialen hos systemen. Resultatet framgick till att återbruk är fortfarande en så pass ny arbetsmetodik och att det ännu inte finns tillräckligt mycket erfarenhet och generella metoder för att ta fram en exakt potential för återbruk hos icke enhetliga produkter. Återbrukspotentialen hos systemen i arbetet togs fram baserat på en fördelning hos delkomponenterna i systemet och samtliga viktades lika. Detta medförde att Modell 4 hade högst återbrukspotential på 53 %, förutsatt att de installerade borrhålen går att återbruka. Finns det inte möjlighet till återbruk hos borrhålen så sjönk resultatet till 28 %. Resterande system uppnådde 40 % återbrukspotential. Resultaten som togs fram i arbetet visar på att systemen inte ska jämföras direkt mellan lokalt och generellt fall. Detta på grund av att storleksordningen i resultaten samt vilket system som har lägst kontra högst värde i de olika fallen ändras. Det går att använda de generella resultaten och jämföra system på generell nivå men då krävs det också att diskussionen är på generell nivå. Detta medför vikten av att för varje enskilt fall kontrollera de lokala förutsättningarna för varje system. Rekommendationen för val av systemen blir därmed projektspecifik beroende på vilket område som värderas högst: energi, klimat, ekonomi eller återbruk. / When determining which heating and cooling system to use in buildings, there are several aspects that can be taken into account. In the past there has been a high focus on energy and economy, but with an increased focus on sustainability and the environment both globally and in Sweden, it has become increasingly important to find robust solutions that perform in all areas. Helenius Ingenjörsbyrå, which are installation consultants in the HVAC, environmental and energy fields, wants to be at the forefront when it comes to energy and the environment. In connection with higher demands on sustainability and the environment, it is of interest to Helenius to see how conventional heating and cooling systems perform when evaluated with respect to energy performance, climate impact, economy and recycling. In addition to this, also see how the result of the systems performance is affected by its geographical location by investigating these areas at a local level (in Uppsala) and at a general level. General level corresponds to an average value for Sweden. This thesis has thus developed a methodology to investigate these areas and suitable systems for the purpose. This work will investigate an office property where heating and cooling is supplied by different conventional heating and cooling systems. The building also has a constant cooling load throughout the year. The four system setups that were developed and investigated in the work were: cooling machine with heat recovery from the condenser heat and separate district heating system (Model 1). The second set-up was a cooling machine with district heating and no option for heat recovery (Model 2). System three was district cooling and district heating (Model 3) and system four borehole storage that utilizes free cooling and heat pumps (Model 4). The result shows that Model 4 was the most beneficial for total energy purchased by the consumer both when investigated locally and generally. The investigated EROI (Energy Return On Investment) showed an advantage for Model 3 both locally and generally. Model 4 had the lowest climate impact in terms of total emitted carbon dioxide equivalents from the life cycle assessment when it was investigated at a local level, in Uppsala. Generally in Sweden, it was instead Model 1 that had the lowest climate impact. The system with the lowest life cycle cost was Model 1 when it was investigated locally for Uppsala, and in the general case Model 3 had the lowest life cycle cost. The distribution of costs between the systems shows that Model 4 has a larger initial investment but was subsequently more self-sustaining and also independent of the markets energy prices. The other systems had lower investment costs and spend most of the life cycle cost on energy, operation and maintenance costs. It also appeared that Model 4 was the setup that held up the most against changes in energy prices, which can be a safety factor for investments over the long term. The work investigated the re-use potential of the systems and the result showed that re-use is still such a new work methodology and that there is not yet enough experience and general methods to produce a fully accurate potential for re-use of non-uniform products. The re-use potential of the systems in the work was developed based on a distribution of the sub-components of the system and all were weighted equally. This meant that Model 4 had the highest re-use potential of 53 %, assuming that the installed boreholes can be re-used. If there is no possibility of re-use at the boreholes, the result dropped to 28 %. Remaining systems achieved 40 % re-use potential. The results produced in this work show that a direct comparison should not be made between local and general cases. This is because the order of magnitude in the results and which system has the lowest versus highest value in the various cases changes. It is possible to use the general results and compare systems on a general level, but then it is also required that the discussion is on a general level. This entails the importance of checking for each individual case the local conditions for each system. The recommendation for what system to go for will therefore be project specific depending on which area is valued the most: energy, climate impact, economic costs or re-use.

I början av 1800-talet började järnvägsnätet i delar av Europa elektrifieras. Då klarade inte motorerna att kommutera vid nätets höga frekvens, 50 Hz, då omformades istället frekvensen till 16,7 Hz. För att växla frekvensen användes roterande omformare. Senare kom mobila omformare som stod på järnvägsvagnar. Dessa omformarstationer var ofta placerade i bergrum. Nu på senare år har tekniken utvecklats och roterande omformare har ersatts med statiska omriktare. Balfour Beatty Rail AB har utvecklat en typ av mobil statisk omriktare som ökar mobilitet samt att stor del av kontroll före idrifttagningen kan utföras i fabrik vilket sparar tid vid idrifttagning av stationen. Ett byte från en mobil roterande omformare till en mobil statisk omriktare i en bergsstation har inte tidigare utförts. Denna förstudie syftar därmed till att ge en beskrivning på vilket sätt en mobil statisk omriktare kan installeras i en befintlig station. För denna studie har Asker omformarstation valts då den är en typisk omformarstation placerad i ett berg. Asker station innefattar tre roterande omformare med en total märkeffekt på 30 MVA. Omformarna förser järnvägen med 15 kV 16,7 Hz från ett 22 kV 50 Hz nät. Asker omformarstation har en begränsad uppställningsyta både inne i bergrummet samt utanför. Det är norska Jernbaneverket som är innehavare av stationen. Studien avser även att kontrollera effektbehovet från Asker station. För att uppskatta effektbehovet utförs simuleringar vid höglastperiod. Simuleringsresultaten används även för att utföra ekonomiska kalkyler i form av LCC-kalkyl samt återbetalningstid med hjälp av pay back-metoden. Två ekonomiska kalkyler har utförts, en kalkyl med restvärde på de omformare som ersätts samt en kalkyl där restvärde av omformarna inte tas i beaktning. En uppgradering där statiska omriktare ersätter roterande omformare skulle i Asker station leda till oförändrad installerad effekt, då platsbrist medför att de tre roterande omformarna inte kan ersättas med fler än två mobila statiska omriktare. De minskade förlusterna medför en vinst om ca 2 miljoner NOK per år. Ett restvärdeskrav kan ställas på de tre roterande omformarna på minst 51,5 miljoner NOK för att uppnå en ekonomisk lönsamhet / In the beginning of the 19th century the railway in Europe was electrified. The engines of that time were not able to commutate at the high frequency of the grid for electric distribution, 50 Hz. This problem was solved by installing rotary converters that changed the frequency to 16.7 Hz. Nowadays static converters has replaced rotary converters to change the frequency in many stations. Balfour Beatty Rail AB has developed a mobile static converter system that makes commissioning tests possible to do in an earlier stage at the manufacturer. This testing minimizes the time spent on site for installation and startup. This bachelor’s thesis is a study that covers if it is possible to exchange a rotary converter with a static converter for railway use and how such a change can be made, mechanically and electrically. For this study Asker converter station in Norway 20 km west from Oslo has been chosen for a case study. Asker is a station that has three rotary converters of the largest type used for electrifying the railway at 10 MVA each. The rotary converters supply the railroad with a 15 kV 16.7 Hz voltage from a 22 kV 50 Hz grid. Asker is a station which is placed within a mountainside. This is a standard type of installation for a rotary converter station. Asker station has a limited area both inside and outside the station. Asker converter station is owned by Norwegian Jernbaneverket. The static converter station must be powerful enough to handle the load of Asker station. This load is simulated by using the timetable of a high load-period. This study also has the purpose of providing an economic view of the exchange since a static converter has a lower energy-loss than a rotary converter which could lead to an economic gain for the owner of the station. In Asker station the three rotary converters will have to be replaced by two mobile static converters because of the stations limited capacity. From the lowered losses a gain of 2 million NOK per year can be made. If the residual value of the three rotary converters can reach 51.5 million NOK it will lead to an economic viability