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Effektivitet av primärenergianvändning hos värmelagringssystem : En beräkningsmodell i SimulinkIvansson, Victor January 2018 (has links)
En stor del av samhällets miljöpåverkan har ursprung hos bostaden, p.g.a. ineffektiva byggnader/energisystem och de boendes attityd mot energianvändningen. PEF är en förkortning för primärenergifaktor, vilket berättar hur mycket primära energiresurser som används för en källa. Examensarbetet undersökte uppvärmningssystem kombinerat med värmelagringssystem till en villa, med fokusering att finna den högsta verkningsgraden av primärenergianvändning samt uppfylla komforttemperatur och varmvattenbehov. Syftet med arbetet var att utöka kunskapen om bostäders uppvärmning integrerad med värmelagring, för att kunna minska användningen av primärenergi till framtida byggnader. Målet med arbetet var att besvara två frågeställningar: Frågeställning 1: Vilken systemlösning ger den högsta verkningsgraden av primärenergianvändning och samtidigt uppfyller värmebehovet? Frågeställning 2: Hur mycket reducering av miljöpåverkan ger det optimerade systemet jämfört med en vanlig villas uppvärmningssystem? De studerande uppvärmningssystemen var solfångare och värmepump. Värmelagringssystemen var fasomvandlingsmaterial, ackumulatortank och borrhålslagring. En vanlig villas uppvärmningssystem bestämdes till en luftvärmepump, en mindre ackumulatortank och ett kompletterande el-element. Arbetet genomfördes i en litteraturstudie där information hämtades via akademiska böcker, vetenskapliga rapporter, myndigheter och lämpliga webbplatser. För att besvara frågeställningarna byggdes en teoretisk beräkningsmodell i Simulink. Resultatet av undersökningen redovisade att systemkombinationen solfångare, ackumulatortank (med el-patron) och fasomvandlingsmaterial gav den högsta verkningsgraden av primärenergianvändning. Med en beslutsamhet att systemlösningen kan tillämpas på alla geografiska platser där uppvärmningsbehov förekommer och solinstrålningen är minst lika hög som Mellansverige, övrig geografi bör också tillämpa ackumulatortank och fasomvandlingsmaterial, men ersätta solfångaren. / A large part of society's environmental impact originates from the housing, due to inefficient buildings/energy systems and the attitude of the residents energy use. PEF is an abbreviation for primary energy factor, which tells you how much primary energy resources are used for a source. This degree project investigated heating systems combined with heat storage system for a villa, focusing on finding the highest efficiency of primary energy and simultaneously fulfill comfort temperature and hot water needs. The purpose of the work was to expand the knowledge of heating systems integrated with heat storage, in order to reduce the use of primary energy for future buildings. The aim of the work was to answer two questions: Question 1: Which system solution gives the highest efficiency of primary energy use and simultaneously satisfy the heating needs? Question 2: How much reduction of environmental impact provides the optimized system compared to a standard villa heating system? The investigative heating systems were solar collectors and heat pumps. The heat storage systems were phase change materials, storage tank and borehole storage. A common villa heating system was determined as an air heat pump, a smaller storage tank and a supplementary electrical element. The work was conducted in a literature study where information was obtained through academic books, scientific reports, authorities and appropriate websites. To answer the questions a theoretical calculation model was built in Simulink. The result showed that the system combination solar collector, storage tank (with electric cartridge) and phase change materials gave the highest efficiency of primary energy use. With determination the system solution can be applied to all geographic locations where heating needs are present and solar radiation is at least as high as Central Sweden, other geography should also apply storage tank and phase change materials, but replace the solar collector.
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Investigation of energy retrofits of a multi-family building by using IDA Simulation SoftwareAhmed, Basem January 2014 (has links)
Energy simulation in building sector was an important issue which can eliminate energy use and improve energy efficiency. The building, which is located at Ringvägen 18 in Ljusdal community in Sweden, was chosen to be the main mission of this research and it was one of eleven objects which were involved in EKG project. First step was to create the model and simulate it to reach heating value of 117 MWh which was reached by EKG project. After getting validation value, many renovations were implemented and the heating value was reduced by 58.7% and the heating demand by 55.2%. Improving of energy use through prefabrication gave reduction of heating value of 70.4% and heating demand of 65.8% The LCC part was important issue because it gave clear vision and judgment about the economic and investment issue. The acceptability of the investment decision was decided by 198 answers which were responsible to judge if the investments were good or not. There were 22 types of different renovation and every type included 9 cases which depended on interesting rate and energy price factors. The result was 198 answers which were divided to 100 answers as “YES” for good investment and 98 answers as “NO” for good investment.
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Automated Testing of HVDC Control & Protection Systems : A study on Automated Regression TestingHalvarsson, Hampus January 2018 (has links)
Testing is an important activity when developing a system. Testing requires resources in terms of time, labour and money. By correctly automating the tests, the development time may either be shortened or there will be a possibility to run more tests. ABB in Ludvika has developed MACH, a control & protection system for HVDC (high power electrical transmission over long distances) applications. During development of the control & protection system for each HVDC project, which are all unique, the system is today tested manually, which takes considerable time.This thesis project studies the possibility of automating parts of the MACH system tests, by investigating current testing procedures, the control & protection system itself, and how a test tool may interact with the system. Using this information a test framework, aimed towards test automation, was created, and a simple test execution tool was developed. A new test case, a combination of multiple smaller test cases, ranon the system using the test execution tool.The outcome proves the proof of concept of automating parts of the system tests.The economics and the scope of the automated testing however, is dependent on how automation is implemented.
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Energieffektivisering av ventilationssystem i en skola : Behovsstyrd ventilation i fastigheten Eken i Karlstad kommun / Energy Efficiency of Ventilation System in a School : Demand-Controlled Ventilation for a Building in KarlstadJohansson, Josefina January 2018 (has links)
I Sverige står bostads-och servicesektorn för nästan 40 % av den totala energianvändningen och därför har många byggnader behov av energieffektivisering. Arbetet utgår från Eken, en del av Karlbergsskolan i centrala Karlstad, som är en kulturmärkt byggnad från 1890-talet. I byggnaden pågår gymnasieutbildning, förskola samt idrottsverksamhet i en gymnastiksal. Byggnaden ventileras i dagsläget med konstant luftflödessystem (CAV). Behovsstyrd ventilation (DCV) innebär att reglera ventilationen efter närvaro och behov, genom att upprätthålla en bra luftkvalité och termisk komfort och samtidigt effektivisera energiförbrukningen. Syftet med detta arbete var att undersöka hur behovsstyrning med IR-sensorer eller CO2-sensorer kan påverka energiförbrukningen och driftkostnader av Ekens ventilationssystem, samt undersöka hur innetemperaturen påverkas vid CO2-reglering jämfört med befintligt driftfall. Målet var att beräkna årliga energibesparingar (MWh/år) och investeringsutrymme (kr) till utgifter som uppkommer vid ombyggnation av dagens CAV-system. Ett ytterligare mål var att beräkna innetemperatur vid olika fall då förutsättningar som rumsplacering, solinstrålning, utetemperatur och intern personbelastning varieras och beroende på CO2-reglerat eller konstant luftflöde. Energibesparingar avseende energi till fläktar och värmebatterier, beräknades i Excel baserat på olika luftflöden beroende på personbelastning. Investeringsutrymmet beräknades utifrån årliga besparingar av driftkostnader. Innetemperaturer beräknades i en dynamisk simuleringsmodell för tre dygn och tre rum med olika förutsättningar. Energibesparingar för IR- och CO2-reglering av ventilationssystemet resulterade i 53 MWh/år (-44 %) respektive 77 MWh/år (-64 %) jämfört med befintligt CAV-system. Efter 15 år bidrog IR- och CO2-reglering till besparingar på ca 520 kkr (IR) respektive 750 kkr (CO2). Skillnaden på innetemperaturen vid behovsstyrt flöde jämfört med konstant luftflöde var lägre än en grad i majoriteten av fallen. Den största skillnaden på 2,7 °C uppstod en solig dag för ett rum med fönster mot sydost. Behovsstyrning är uppenbart fördelaktigt för byggnaden ur energi- och miljöperspektiv. Investeringskostnaden för de två olika metoderna är troligtvis ungefär lika stora och hur ekonomiskt lönsam investeringen är beror på återbetalningstiden. Luftflödesreglering leder inte till några större problem för rumstemperaturen och i annat fall borde temperaturproblem kunna åtgärdas genom solavskärmning eller temporärt ökat ventilationsflöde. / In Sweden, the housing and services sector accounts for close to 40 % of the total energy use, hence why many buildings require energy efficiency. This study is based on the Eken building, which is a historical building from the 1890s, a part of Karlbergsskolan in central Karlstad. The building operates with a secondary education, preschool and a gymnasium. It is currently ventilated by a constant air volume-system (CAV). Demand controlled ventilation (DCV) involves controlling the ventilation according to occupancy and requirement, by maintaining acceptable indoor air quality and thermal comfort, while simultaneously decreasing the energy consumption. The purpose of this study was to investigate how demand-controlled ventilation can improve energy efficiency and operating costs of the ventilation system in Eken, using either IR- or CO2-sensors, as well as investigating how indoor temperature is affected by reduced air flow due to CO2-controlled ventilation. The goal was to calculate the annual energy savings (MWh/year) and anticipate the investment range (SEK) for expenses incurred in rebuilding the current CAV-system. An additional goal was to calculate indoor temperature due to CO2-controlled airflow or constant airflow (CAV) under different circumstances. We did this by varying conditions such as location, solar radiation, outdoor temperature and occupancy. Energy savings for fans and heaters were calculated in Excel, based on different airflows depending on occupancy. The investment range was calculated on the basis of annual savings of operating costs. Indoor temperatures were calculated with a dynamic simulation model for three days, in three rooms, with different conditions. Energy savings for an IR- or CO2-controlled ventilation system resulted in 53 MWh/year (- 44 %) and 77 MWh/year (-64 %) respectively compared to consisting CAV-system. After 15 years, IR- and CO2-regulation contributed to savings of about 520 kkr (IR) and 750 kkr (CO2). The difference of indoor temperature during the demand-controlled flow rate in comparison to constant airflow, was less than one degree in the majority of cases. The biggest difference of 2,7 °C occurred on a sunny day in a room with windows facing southeast. Demand-controlled ventilation is clearly beneficial from an energy- and environmental perspective. The investment cost of the two different methods is probably about the same range and the economic profit depends on the payback period. Airflow regulation does not lead to any major temperature problems, however if there are any problems they may be addressed by solar shielding or temporarily increased air flow rate.
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Prognostisering av fjärrvärmekunders effektförbrukning : Metod för hur Stockholm Exergi kan öka kvaliteten i simuleringsmodeller av fjärrvärmenätetStålnacke, Joakim January 2018 (has links)
A method for predicting consumer heat power usage was examined, for the purpose of implementing such a method in simulation models of the district heating distribution network at Stockholm Exergi. This was to enhance the results of such simulations and aid the company’s work with distribution optimization. A method based on power signatures, which are models currently used in many applications, was examined. The method aspired to describe the consumption patterns of consumers over time and temperature, categorize consumers according to these patterns and then implement the results in the simulation models. The addition of a time parameter to the signatures resulted in an improved and more consistent prediction quality. Categorizing the consumers mathematically caused only a minor decrease in the prediction quality and resulted in better prediction quality than the categorization system currently used. Stockholm Exergi is adviced to keep examining mathematical categorization of consumers as such a categorization has several advantages to the one currently used. It is also recommended to examine options to Termis for performing individual consumer predictions as the program is not well suited for it. Such options could be other software or add-ons to Termis which make such predictions more viable.
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Utvärdering av behovsstyrt ventilationssystem i skolbyggnad : Energieffektivisering av ventilationKindblom, Johan January 2017 (has links)
New buildings today are built with great care and contain modern technology in order to minimize the energy cost and therefore also their upkeep. This project has tried to evaluate the effect of a smart demand-controlled ventilation system which measures the actual airflow demand and adjusts accordingly. By using exact data from a system inside a school and studying the building itself, an accurate model of the school was created. Using this model the demand-controlled system was compared to a conventional, constant flow, system. The results showed that the demand-controlled system reduced the specific energy consumption of the school by 34 % and that the systems components could be downsized to 70 % of the original size. This means that this kind of integration of control technology is a powerful tool to further increase the energy efficiency in buildings.
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Energy flow mapping of a sports facility : Energy flow mapping and suitable key performance indicator formulation for Rocklunda sports facilityEskilsson, Anton January 2017 (has links)
No description available.
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Evaluation of energy conserving measures in buildings connected to a district heating system : case studies in Gävle, SwedenGustafsson, Mattias January 2016 (has links)
When different energy conserving measures are implemented for reducing energy use in buildings and the buildings are connected to district heating systems, it is important that an overall system analysis is made which takes into account the effects of total change of energy use due to the energy conserving measures. The method applied in this thesis uses hourly production data for the different production units in the district heating system in Gävle, Sweden. The merit order of the different production units is dependent on the electricity spot market price. To calculate the merit order, hourly data for the electricity price is used. The marginal production unit can then be determined for each hour of the investigated year. This thesis analyzes five different energy conserving measures in a multi-dwelling building regarding how they affect the marginal production units in the district heating system. For CO2 emission evaluations, two different combinations of heat and electricity conserving measures are compared to installation of an exhaust air heat pump. This thesis also analyzes how the configuration of the electric meter affects the measured amount of self-consumed and produced excess electricity for a single-family house and for two multi-dwelling buildings of different sizes. The results show that the use of electricity is the most important objective to consider. The increased use of electricity for operation of the heat pump contributes to an increase of global CO2 emissions and the electricity produced by the solar photovoltaic installation contributes to a decrease of global CO2 emissions. The results also show that the configuration of the electric meter is important for the single-family house but negligible for the multi-dwelling buildings. The amount of produced excess electricity is high for all buildings, which means that the economic value of produced excess electricity is important for a profitable installation.
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Energiutvinning från deponigas : På Holmby återvinningscentral / Energy Recovery from Landfill Gas : At Holmby RecyclingstationNilsson, Aron January 2017 (has links)
I det här arbetet har det undersökts huruvida mängden deponigas i deponin vid Holmby återvinningscentral i Sunne är tillräcklig för att täcka värmebehovet för ett antal lokaler i närheten, om deponigasen kan ge säljbar el, och om detta kan göras ekonomiskt lönsamt. De processer som har undersökts är en gasmotor, en gasturbin och gaspanna från Biogassystems och en Stirlingmotor från Cleanergy. Dessa har tillsammans med en ackumulatortank simulerats för att undersöka om de kan klara av att leverera den värme som behövs för att täcka behovet utan att bli för dyra och vilka utsläpp det resulterar i. Det finns i dagsläget ett uttagssystem för deponigasen och all energi facklas i nuläget bort. Energin borde tas tillvara då den kan ersätta andra mer miljöskadliga energikällor. Utöver resultaten i det här arbetet tillkommer kostnaderna och miljöpåverkan för distributionen av den producerade värmen och elen. Arbetet är upplagt så att det produceras den värme som behövs för att täcka värmebehovet. Värmebehovet styr därmed hur mycket el som produceras, då ingen el produceras när det inte finns något behov av värme och den el som inte används till eget bruk säljs. För beräkningar har programmet Matlab och funktionen Simulink använts. Det visade sig att alla metoder med deras respektive verkningsgrader och andra begränsningar klarade av att producera värme i den grad att de klarade att täcka det värmebehov som satts upp samtidigt som en hel del el skulle kunna säljas med tre av metoderna, dock inte med gaspannan då den inte producerar någon el överhuvudtaget. Gasturbinen blir klart dyrast på grund av dess höga pris och låga el-verkningsgrad. Det är därmed tveksamt om det skulle vara lönsamt att satsa på en gasturbin som lösning för att ta om hand om energin i deponigasen. Den rekommenderade lösningen är att använda sig av en gaspanna om det inte finns något intresse av att sälja el då den utan några problem klarar av att leverera den värme som behövs samtidigt som den är billigast. Om det däremot finns ett intresse av att sälja el hade en stirlingmotor varit att föredra då den klarar av värmebehovet samtidigt som den producerar el som kan säljas. Detta i kombination med att den inte är lika känslig för föroreningarna i deponigasen som gasmotorn gör den till det bästa alternativet för en kombinerad värme- och elproduktion. / In this study a evaluation has been conducted to whether the amount of landfill gas in the landfill at Holmby recycling station in Sunne could be used to cover the heat needed to heat up a couple of buildings nearby, how much electricity that would be produced in the process and if there would be any economic gain in doing so. The machinery used in this study is a natural gas engine, gas turbine and a gas fired boiler from Biogas Systems and a Stirling engine from Cleanergy. These have been evaluated together with a heat storage tank to see if they could produce enough heat for the buildings. The system in place today only uses a torch to dispose the gas and no energy from the gas is used. The energy in the gas should be taken care of because it could replace other energy sources that are worse for the environment. Beyond the results in this study you will have to consider the distribution of the produced heat and electricity. The main thought is that you will produce the heat needed and sell the electricity you don’t use yourself. The calculations have been conducted in Matlab and the tool Simulink. The results showed that you can produce enough heat with all the examined apparatuses, with their efficiencies and other restrictions at the same time as you could sell a fair amount of electricity by using three of them, the only exclusion is the gas fired boiler as it doesn’t produce any electricity. The gas turbine becomes very expensive due to its price and the relatively small electric efficiency. It is a possibility that you won’t make any money from a system with a gas turbine. A gas fired boiler is the recommended machinery if there is no interest in electricity production due to its ability to produce the heat needed at the same time as it is the cheapest of the tested machinery. If on the other hand there is an interest in electricity production the Stirling engine would be the recommended machinery. The Stirling engine manage the heat needed in the buildings at the same time as it produces electricity that could be sold. The reason that the Stirling motor is the preferred machinery in this case is that it is not as sensitive to the pollutions in the landfill gas as the natural gas combustion engine.
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Efficiency comparison between Heat Pump andMicro CHP located in two different location inSwedenAl-samuraaiy, Omar January 2016 (has links)
Efficiency of a ground source heat pump with thermal capacity of 6 kW determined in two differentlocations in Sweden. In the north side with low average temperature which could go down to -10 ᵒCand in the south side, with low average temperature with +2 ᵒC. The heat pump has refrigerantR407c, which could be connected to both, ground source heat feeding methods the horizontal, andthe vertical model. The heat pump give heat for both space heating and domestic hot watercompared the micro CHP which has thermal capacity of 12.5 kW and electrical capacity of 4.4 kW. Ithas IC engine which means the engine has internal combustion work. It also works with two kinds offuel, natural gas and propane MOZ 92; the energy and exergy of the fuel in micro CHP feeding thethermal process by heat. That heat used for space heating and domestic hot water after going outthe process for the cooling which keep the heat in storage tank and it heat the liquid to the gas to beused in the turbine to produce the electricity. The two locations in the north and south of Swedenwill influence the thermal operation and that influence power used for compressor for heat pumpand somehow the pump in the micro CHP. The study shows that the different in exergy and energyefficiency between these two heat technologies by located them in the locations. Higher efficiencyof the micro CHP which give the advantage of use Micro CHP some technology give the benefit byusing the fuel for producing the heating and electricity , the benefit which give the customer manybenefit shows in the study. That’s comparing with the heat pump which is large use in Sweden. Inthis paper will introduce Micro CHP as heating technology which has been used in the rest of Europecould be used in Sweden for future heating technology with electricity producing, shall change thecostumer from energy consumption costumer to producing costumer.
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