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LEK3 - Hållbar fastighetsanvändning genom samverkan : Mervärden vid energieffektiviseringar / LEK3 - Sustainable real estate use by cooperation : Energy efficiency and multiple benefitsPetersson, Frida January 2019 (has links)
LEK3 - Hållbar fastighetsanvändning genom samverkan
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Solar Powered Air Conditioning SystemIbrahim, Munzer January 2019 (has links)
No description available.
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Increasing the value of household appliances by adding a heat pump systemBengtsson, Peder January 2014 (has links)
Historically, domestic tasks such as preparing food and washing and drying clothes and dishes were done by hand. In a modern home many of these chores are taken care of by machines such as washing machines, dishwashers and tumble dryers. When the first such machines came on the market customers were happy that they worked at all! Today, the costs of electricity and customers’ environmental awareness are high, so features such as low electricity, water and detergent use strongly influence which household machine the customer will buy. One way to achieve lower electricity usage for the tumble dryer and the dishwasher is to add a heat pump system. The function of a heat pump system is to extract heat from a lower temperature source (heat source) and reject it to a higher temperature sink (heat sink) at a higher temperature level. Heat pump systems have been used for a long time in refrigerators and freezers, and that industry has driven the development of small, high quality, low price heat pump components. The low price of good quality heat pump components, along with an increased willingness to pay extra for lower electricity usage and environmental impact, make it possible to introduce heat pump systems in other household products. However, there is a high risk of failure with new features. A number of household manufacturers no longer exist because they introduced poorly implemented new features, which resulted in low quality and product performance. A manufacturer must predict whether the future value of a feature is high enough for the customer chain to pay for it. The challenge for the manufacturer is to develop and produce a high-performance heat pump feature in a household product with high quality, predict future willingness to pay for it, and launch it at the right moment in order to succeed. Tumble dryers with heat pump systems have been on the market since 2000. Paper I reports on the development of a transient simulation model of a commercial heat pump tumble dryer. The measured and simulated results were compared with good similarity. The influence of the size of the compressor and the condenser was investigated using the validated simulation model. The results from the simulation model show that increasing the cylinder volume of the compressor by 50% decreases the drying time by 14% without using more electricity. Paper II is a concept study of adding a heat pump system to a dishwasher in order to decrease the total electricity usage. The dishwasher, dishware and water are heated by the condenser, and the evaporator absorbs the heat from a water tank. The majority of the heat transfer to the evaporator occurs when ice is generated in the water tank. An experimental setup and a transient simulation model of a heat pump dishwasher were developed. The simulation results show a 24% reduction in electricity use compared to a conventional dishwasher heated with an electric element. The simulation model was based on an experimental setup that was not optimised. During the study it became apparent that it is possible to decrease electricity usage even more with the next experimental setup.
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Hållbar uppvärmning : Vilket är det mest hållbara alternativet för uppvärmning av en nybyggd villa i Östersunds tätort?Turunen, Maria January 2019 (has links)
Rapporten jämför frånluftsvärmepump, luft-vattenvärmepump, bergvärmepump, frånluftsvärmepump med fjärrvärmespets och pelletspanna för en nybyggd villa i Östersund. Det finns fem olika framtidsscenarier med varierande utfall av elmix samt elpris och är en känslighetsanalys för elprisets påverkan och miljöbelastning för respektive uppvärmningsalternativ. För att kunna jämföra de olika uppvärmningsalternativen så används ett referenshus som är baserat på tillverkarens uppgifter och fyra modellfamiljer som använder olika mycket energi. De olika familjerna används för att undersöka om utfallet för det mest hållbara uppvärmningsalternativet varierar för de olika livsstilarna. Resultatet baseras på de tre delarna inom hållbarhet nämligen ekonomisk, ekologisk och social hållbarhet. Den ekonomiska delen innefattar installationskostnader, inköpspris, ränta, driftskostnader och för pelletspannan ingår även kostnaden för byggnation av pelletsförråd och för bergvärmepumpen är även kostnaden för borrning av energibrunn inräknad. Den ekologiska hållbarheten bygger på att använda miljöbelastning som instrument och den baseras på vilken mängd energi som behövs för att säkerställa uppvärmning utav huset och presenteras som koldioxidekvivalenter, CO2eq, och det innebär att alla utsläpp relaterade till energins ursprung har omvandlats till likvärdig mängd koldioxid. Den sociala hållbarheten är beroende av de andra två delarna tillsammans då låg miljöbelastning innebär att fysiska och psykiska behov kan tillgodoses genom god inomhusmiljö med bra ventilation och behaglig värme samt att det finns en utemiljö som tillgodoser behovet av bland annat frisk luft och en levande natur och med en låg ekonomisk kostnad så har individen möjlighet att uppfylla sina drömmar. Det rapporten har kommit fram till är att bergvärmepumpen har den lägsta miljöbelastningen, den lägsta driftskostnaden oavsett scenario och livsstil samt den näst lägsta totalkostnaden vilket gör att den uppfyller rapportens kriterier för hållbarhet / The purpose of this report is to compare different types of heatingsystems for newly built houses in Östersund. The heatingsystems of the report is exhuast air heatpump, air/water heatpump, ground source heatpump, exhaust air heatpump in combination with district heating and pellet boiler. The comparison is based upon sustainibility and its three dimensions, economy, ecological and social sustanibility. The foundation that the comparison rely on is five different future scenarios with varying mixes of sources for electricity and includes electricity prices as well. The enviromental impact is based on the different sources of energy that is used in each scenario and is measured in carbondioxide equivalents CO2eq. The results are based on the three components of sustainability, economic, ecological and social sustainability. The economic part includes installation costs, purchase price, interest, operation costs and for the pellet boiler it includes the cost of building a pellet storage and for the ground source heat pump the cost of drilling is included. The conclusion of this report is that the ground source heat pump has the lowest environmental impact, the lowest operating cost regardless of the scenario and lifestyle and the second lowest total cost, which means that it meets the criteria for sustainability of the report
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Design and Mathematical Modelling of a Solar Carport with Flat ReflectorSrinivasan, Suriya January 2019 (has links)
As the world is moving towards the renewable energy, there is increase in usage of the electric vehicles in transport sector. This has led to more consumption of electricity from the grid and thus affecting its stability. To overcome this issue many decentralized charging stations have come of which generating electricity from the solar energy is more popular. These solar carports act as a shelter for the vehicles from various climatic factors such as rain, snow, dust in addition to producing renewable electricity. The main aim of this thesis study is to design a solar carport with the reflector compared to the existing Solar carports. The roof selected for this thesis study is a “V” shaped roof with the PV modules installed on one side of the roof and a reflector installed on the other side of the roof. The objectives of this thesis study are creating a mathematical irradiation and yield model of the PV system with and without a reflector. In addition, find the optimum roof tilt angle for a PV system with the reflector. Finally, determine the optimum increase in the annual energy yield for a PV system with the reflector compared to the PV system without a reflector. Microsoft Excel is used to create the mathematical irradiation and yield model of the PV system. The simulation was done for three different locations by obtaining hourly irradiation and temperature data from the PVsyst software. As a case study four different reflective materials of different specular and diffuse reflectance were chosen for better understanding and comparison. The simulation results showed that there is significant increase in the annual energy yield for a PV system with the reflector for all the locations. The study also shows that the increase in energy yield, optimum roof tilt angle is dependent on the specular and diffuse nature of the reflector. The study has concluded that the increase in the annual energy yield for a PV system with the specular reflector is more compared to a PV system with the diffuse reflector for the lower roof tilt angles and vice versa. It is also clear that the increase in the energy yield is similar for all the three locations. Hence, based on the roof tilt angle the selection of the reflector material needs to be done for an optimum design of the solar carport.
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Nutidsbeskrivning av PFAS i dagvatten för området Frösö Park : Med fokus mot reningsmetoder och hur PFAS-situationen ser ut för framtidenJohansson, Tore January 2019 (has links)
PFAS is a relatively new group of contaminants with unique characteristics, which in the early 21st century was understood being dangerous for both humans and the environment. In 2008, EFSA published a report on guidelines for human intake of PFAS. Target and limit values for ground and surface water around the world has been based on the information in the EFSA report. In the end of 2018, EFSA published a new preliminary report with new target values for PFAS, well below the target values published in 2008. Frösö Park in Östersund, Sweden, is polluted by PFAS from the time that the Swedish Armed Forces were active in the area. While the Swedish Armed Forces exercised their activities at Frösö Park, large amounts of aqueous fire-fighting foams were used, mainly for training purposes. AFFF at that time contained a mixture of many highly fluorinated chemicals known as PFAS, a collective name of more than 4,700 chemicals consisting of carbon-fluorine bonds. PFAS are, more or less, persistent, bioaccumulative and toxic. This study focuses on PFAS11, which Sweden has target and limit values for in respect of ground water and surface water (lake and sea). PFOS is the most common PFAS chemical and the most commonly occurring PFAS chemical at the Frösö Park area. Today, there is a combined urban runoff and waste water network at the Frösö Park area. The internal water conduit system is currently being examined in order to, eventually, disconnect the urban runoff from the waste water network in order to instead release the urban runoff to Storsjön in the immediate area. As the urban runoff has high levels of PFAS, it must be purified before it is discharged to the recipient. High levels of PFAS has been found in the sewage treatment plant. The sewage treatment plant is not able to purify the water from PFAS, which means that the pollution is discharged into Östersund’s drinking water source, Storsjön. The Municipality of Östersund wanted this thesis as the study will include newsworthy information and provide the municipality more knowledge about the PFAS issues in the Frösö Park area. The aim of this thesis is to examine how the urban runoff from the Frösö Park area can be handled to prevent PFAS leaking out in Östersund’s drinking water source, Storsjön. The thesis describes in a comprehensive way how different purification methods work and the function of the different methods based on the conditions that exist in the Frösö Park area. The purification methods for urban runoff are sedimentation methods, biofilters, and how additives with chemicals can affect the purification of urban runoff. After the urban runoff purification, the purification steps focused on PFAS are sorption methods, chemical redox methods, membrane methods and excavation methods. Based on previous reports for the Frösö Park area, existing data has been compiled into maps, figures and diagrams in order to clearly describe the current PFAS situation. The scientific literature presented herein has been selected by specific keywords in databases. The literature has been supplemented with materials provided by the municipality, tips from researchers and personal contact with other industry-related actors. In the purification steps focused on purifying particles, organic materials and metals in urban runoff, a barrier that restricts the flow of water is proposed, tentatively a dam, wetland or lamellar sedimentation, followed by sand filtration. A large advantage with a barrier restricting the flow of water is the possibility to control the water flow to the next purification step. In the purification steps focused on purifying the water from PFAS, purification with activated carbon, nanofiltration, ion exchange method or sonochemical oxidation are proposed. The purification methods are proposed because of the existing knowledge of the methods and the pollution situation for the Frösö Park area. The research for PFAS with new purification methods, target and limit values for humans and the nature as well as future costs for decontamination and health-related costs means that PFAS currently is a priority contaminant taken seriously. Advantages and disadvantages of the purification methods are presented herein, however, the issues with PFAS are very complex and the purification methods work differently depending on the conditions they are exposed to. In this thesis, the most interesting new information regarding PFAS has been compiled to show the current knowledge situation in order to facilitate for relevant actors to continue their work with the PFAS issues in the future.
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Fouling in biomass fired boilersSandberg, Jan January 2007 (has links)
<p>In order to reduce the discharge of the greenhouse gas CO2, the use of biomass is nowadays promoted as fuel in boilers. Compared to boilers fired with coal and oil the biomass-fired boilers have more complications related to both fouling and corrosion on the heat transfer surfaces. After the combustion, unburned inorganic matter in state of vapour, melts and solid particles are transported in the flue gas and may form deposits on heat transfer surfaces.</p><p>Deposits on the heat transfer surfaces may result in both increasing corrosion and decreasing boiler efficiency as the heat transfer rate to the superheaters and reheaters decrease by deposits.</p><p>In order to understand the process of deposit build-up, the whole combustion and transport process had to be analysed including aspects such as, boiler design, fuel properties and combustion environment, followed by particle transport phenomena and the probability for particles to get stuck on the heat transfer tubes.</p><p>In this thesis numerical simulation of particle trajectories has been conducted as well as measurements of deposits on a special designed deposit probe followed by investigation of on-site measurements of deposit depth on the super-heater tubes in a circulating fluidised bed in Västerås, Sweden.</p><p>Numerical simulations of particle trajectories in the vicinity of two super-heater tubes were conducted in an Eulerian-Lagrangian mode considering the flue gas and ash particles phase. Particle impingements on the tubes were investigated for different particle sizes. The results from the particle trajectory simulations show that particle larger than 10 µm will mainly impinge on the windward side of the first tube but, however also on the sides of the second tube in the flue gas flow direction. In theory as well as from observations and measurements two tubes can merge together by the deposit build-up. Smaller particles are usually more dispersed due to turbulence and thermophorectic forces, resulting in a more even impingement distribution on the whole surface of the tubes.</p><p>Probe measurements reveal that the deposit layer growth rate have a significant temperature and time dependence. After the initial deposit build-up a sintering process occurs and sintering is also proven to be dependent on temperature and exposure time.</p><p>Soot-blowing is the most common method to reduce the effect of deposits on the heat transfer tubes. In the present thesis the soot boiling efficiency is therefore also investigated. The soot-blowing show a strong positive effect on the heat transfer rate in a short time (hours) perspective after a soot-blowing cycle is completed. This positive effect is much weaker when considering a time period of three years. This is an effect of fact that soot-blowing mostly remove the loose part of the deposit material leaving the hard sintered part unaffected.</p><p>The subject of deposit build up on superheater tubes in large scale boilers involves multi-discipline knowledge and historically, the related research is mostly conducted as measurements and experiments on operating plants. Possibly in the future, theoretical simulations will have a bigger part of research on deposit build-up where the calculations are to be calibrated through measurements on real sites plants.</p>
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Modellering av Panna 5 Mälarenergi AB : utveckling av en beräkningsmodell med simuleringsverktyget IPSEproÖberg, Filip January 2009 (has links)
<p>Heat and power stations are often in need of optimizations. A simulation model is a tool for findingways to optimize the plant. The scope of this diploma work is to develop a simulation model ofBoiler 5 at Mälarenergi AB. Boiler 5 is a circulated fluidized bed boiler that was taken into service inyear 2001. Among the included parts in the boiler are cyclone, convection part andINTREX-chambers. The software that was used for the simulation was SimTech’s IPSEpro. IPSEprois a heat and mass balance software for steady state calculations. The program comes with a set ofmodules in a library called APP_lib which contains modules such as preaheaters, pump, boiler andturbine stages. The user can however design own modules in the Model Development Kit, since thelibrary code is open source. The development of the simulation model started with an updating of anold model from year 2003. Values provided from Foster Wheeler where then used to make the modelcalculate in a right way. Thereafter some calculations of the super heaters’ heat transfer coefficientswere made. The coefficients were then translated into IPSEpro’s own programming language ModelDescription Language, and were put into the model’s modules. The results were compared with realvalues from the plant’s system. It showed that the calculated values needed more investigations to bemore accurate. The conclusion was that the final model needs more equations to describe the plant in amore realistic way.</p>
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Samkörning mellan värmepumpar och fjärrvärme : Bostadsrättsföreningen BogårdenSadik, Zidar January 2008 (has links)
<p>This diploma work covers an investigation over the heat - and hot water systems of the</p><p>tenant-owner's association, Bogården. The heat - and hot water needs of Bogården are</p><p>satisfied by both district heating as well as three heat pumps. Implemented investigation</p><p>shows that the heat pumps are not used in a profitable way. Apart from that, the reserve</p><p>possibilities are small. There is also a risk of the growth of Legionella bacterium in the</p><p>hot water system.</p><p>Since the heat pumps are already installed, HSB-Gävleborg (responsible for Bogården)</p><p>has a wish to investigate possible proposed actions for optimization of existing plant.</p><p>After completed investigation, a new proposed action is presented. The new proposed</p><p>action goes on intercepting the hot water production and using the heat pumps to only</p><p>heat production during the heating season. Why the hot water production should be</p><p>intercepted, is just in order to eliminate the risk of Legionella. Besides, the new proposal</p><p>is going to bring about a reserve of 1,534,000 SEK during a twenty-year period. This is</p><p>approximately twice as much as what the existing plant may bring during the same</p><p>period.</p><p>During the work's review, it also has been established that heat - and hot water systems</p><p>are error regulated. Since the diploma work does not cover that piece it is instead</p><p>informed as proposals subject to further investigation.</p>
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Simulering av luftströmningen och temperaturfördelningen i ett kondensorskåp / Simulation of airflow patterns and temperature distribution in a condensation cabinet dryerRezk, Kamal January 2007 (has links)
<p>Drying laundry has become a huge consuming factor of energy in residential areas through drying machines as tumble dryers and cabinet dryers. In USA the increasing use of drying machines in households increased from 40% during the 1970 to 80% in the 1990, which correspond to a usage of approximately 76 million drying machines.</p><p>The European market for drying cabinets is not huge. It is mainly Scandinavia that is using cabinet dryers for drying laundry these days. Nowadays cabinet dryers that use hoses to evacuate humid air out the building are developed in the market. Asko Cylinda AB has developed a new condenser cabinet dryer out of a regular cabinet dryer. With the new condenser cabinet dryer no hoses are required because the drying process take place in a closed recirculation system. Several openings at the back of the condenser cabinet dryer make it possible to dry laundry horizontal in different sections.</p><p>In this thesis the condenser cabinet dryer has been studied in a simulation program that is called Comsol MultiPhysics. A 2-dimensonal model was created where the airflow patterns and temperature distribution in the dryer was simulated. On the basis from the basic model of the dryer several modifications was created to attain knowledge of which modifications contributes to an improved airflow pattern.</p><p>The temperature distribution in the condenser cabinet dryer is uneven in the sections according to the simulations the air distribution is good in section 2 and 3 in the basic model. The factor that has the largest impact on the air distribution is the air stream that flows up at the back inside the cabinet, the air stream restrains a part of the hot air jet from the openings at the back. Case 1.1 is the modification that created the best airflow profile, which contributed to an even temperature distribution. In the modification the textiles were used to cover up the space at the back of the cabinet to eliminate the air stream to flow up between the textile and the openings. The effect transport between the textile and the air increased with 50 % at several sections when the modification was carried out according to case 1.1.</p><p>This study is a good basis for further studies in simulation of airflow and temperature distribution in the condenser cabinet dryer. The next step in the study is to create a 3-dimensional model of the cabinet. With this study the 3-D model could be accomplished easier by using parameters from the 2-D model as data on the boundaries. By doing so the system could be delimited, this would reduce the use of computer capacity.</p> / <p>Torkning av kläder har med tiden utvecklats till att bli en stor faktor av energiförbrukning i bostadsområden genom maskiner som bl. a. torktumlare och torkskåp. I USA ökade användningen av torkmaskiner i hushåll från 40% under 1970 till 80% i 1990, vilket motsvarar en användning av ca 76 miljoner torkmaskiner.</p><p>Marknaden för torkskåp är inte stor i Europa. Det är främst Norden som använder torkskåp för torkning av kläder. I dagsläget tillverkas s.k. avluftarskåp, d.v.s. det krävs en slang ut ur huset för att evakuera den fuktiga luften. Asko Cylinda AB har på senare tid utvecklat ett nytt kondensorskåp av ett sådant avluftarskåp. Med det nya kondensorskåpet behövs det inte någon evakueringsslang ut ur huset eftersom torkningen sker i ett recirkulerande system. Gälarna i bakkanten av torkskåpet möjliggör plantorkning eftersom luften skickas in i flera sektioner.</p><p>I uppsatsen har kondensorskåpet studerats i ett simuleringsprogram som kallas Comsol MultiPhysics. En 2-dimensionell modell skapades där bl.a. luftströmningsbilden och temperaturfördelningen i skåpet simulerades. Utifrån grundmodellen skapades ett antal modifieringar på kondensorskåpet för att erhålla kunskap om vilka modifieringar som ger bättre luftflödesbilder.</p><p>Temperaturfördelningen i kondensorskåpet är ojämn enligt simuleringarna då luftdistributionen är bäst i sektion 2 och 3 i grundmodellen. Faktorn som har störst påverkan på luftströmningsprofilen är den uppströmmande luften vid baksidan av skåpet, luften bromsar upp den varma luftstrålen ut från gälarna. Fall 1.1 är modifieringen som skapa den bästa luftströmningsprofilen vilket bidrog med en jämnare temperatur-fördelning. I modifieringen användes textilerna för att täppa igen ytorna vid baksidan av kondensorskåpet för att eliminera uppströmmande luft framför gälarna. Effekttransporten mellan textilen och luften ökade med upp till 50 % på flera sektioner då grunduppställningen modifierades enligt fall 1.1.</p><p>Studien i denna rapport är ett bra underlag för fortsatta studier inom simulering av luftströmningen och temperaturfördelningen i kondensorskåpet. Nästa steg i studien är att konstruera en 3-dimensionell modell av skåpet. Med hjälp av den här studien kan en 3-D modell underlättas genom att använda parametrar från 2-D modellen som indata på randvillkor. Genom det kan systemet avgränsas för att minimera 3-D modellens konsumtion av dataminne.</p>
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