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374 Uppsatser om Solar thermal - Sida 14 av 25
Morgondagens effektiva fjärrvärme : En beskrivande litteraturstudie
This report is made as a literature review, focusing on the work done to increase understanding of efficiency in the categories of substations and secondary heating systems, with respect to the deviation from the theoretically possible cooling off in the distribution network as well as the economic benefit that appear. The main purpose of a considerable part of the literature used in this report addresses the issue of identifying individual causes of reduced cooling in district heating systems. These literature resources have been compiled and summarized as part of the report.The technology of district heating is associated with benefits such as better use of the energy in a fuel. This is the case of cogeneration plants where serial generation of electricity and thermal energy increases efficiency compared with the parallel generation where heat is generated locally and electricity is generated centrally. Serial generation thus allows for lower primary energy demand.
Solcellsanl?ggningar p? landsbygden, vad s?ger lokalbefolkningen? En studie om lokalbefolkningens uppfattningar av solcellsanl?ggningar
I samband med en ?kad efterfr?gan och st?rre behov av fossilfri energi kommer storskaliga
solcellsanl?ggningar p? mark att spela en allt viktigare roll. Samtidigt kr?vs ett
h?nsynstagande till lokalbefolkningen som f?r anl?ggningen placerad i sin n?rhet. Tidigare
forskning har visat att b?de ekonomiska, sociala och milj?m?ssiga aspekter g?r att koppla till
n?rboendes acceptans.
Utfackningsvägg av lättbetongblock i passivhus
AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.
Upplevd trafiksäkerhet med mittbarriär
AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.
OTEC-Ett energialternativ för enhållbar ö
Ocean Thermal Energy Conversion (OTEC) is a technology that utilizes the temperaturedifference in oceans between the warm surface water and the cold water at 1000 m depthto produce electricity. The purpose of this report is to investigate if OTEC with its synergiescould become a commercially feasible energy solution for a small island. A literature reviewis conducted to explore the different OTEC technologies and to what extent the threesynergies; fresh water, air conditioning and aquaculture, could be used. In order to calculatethe profitability of these synergies there is also a study conducted on the conventionalmethods and cost of fresh water production, aquaculture and air conditioning. A model is setup using a scenario of a small tropical Island with population of 100 000 people.
Opera i Stockholm, Galärvarvet
Suggestion for a new operahouse in stockholm, förslag på nytt operahus i stockholm. Stockholmsoperan..
Legionella i tappvattensystem. Förekomst och förebyggnade-en redogörelse.
Legionella can be prevented, the question is how. This report is a degree in construction engineering education at Chalmers University in Gothenburg. A comprehensive written publication for Legionella-safe plumbing installations is not available and therefore requested. The purpose of this report is to present preventative measures against Legionella bacteria growth in tap water and in other systems where Legionella bacteria are a potential problem. Technical solutions are presented including how different systems function and what their advantages and disadvantages are.
Hur påverkar gummigolv i grisningsboxen suggans liggtider, liggbeteende och hennes tid för att lägga sig?
In the farrowing pens the amount of bedding material and the quality of the concrete floor has a huge impact on both the sow and the piglets. In this study imbedding of
rubber flooring on the solid area in the farrowing pen was used to see if it had any effects on the sows lying behaviour when compared to concrete. Another important
aspect was to evaluate if the rubber floorings had a high enough durability to resist the normal wear in a farrowing pen. Concrete flooring is assumed to have a higher thermally
conductive effect then rubber which can affect the sow?s chance to cool down.
A Cross-Country Skiwear Collection for Beautiful Women
This thesis deals with cross-country ski clothing for non-competitive women. Women in this category look for different clothing features in comfort and aesthetics than male top athletes, for whom cross-country skiwear today often seems to be designed. In this thesis the demands of these women have been mapped out by an interview with a reference group of users. The ergonomics of exercising in the winter outdoors are naturally a base for the collection. The collection consists of three functional layers of garments.
Lagring av kyla i bergrum : Undersökning av ett nedlagt oljebergrum
This thesis considers the use of an oldrock cavern as thermal energy storage.With a large system of differentchillers a model was created to find anappropriate future system. There aremainly two trajectories to take. Eitheran installation of chillers needs to bemade or the rock cavern can be used tomeet the future demand of districtcooling in Solna, Sweden. Additionallythis thesis investigates the possibleuse of different techniques to utilizethe phase change energy of water.Simulation shows that it?s possible toutilize the phase-change energy of afluid; however it?s not economicallyfeasible due to the thermodynamiceffects on the Carnot cycle.
Förstudie för kvalitetssäkringav glidande förband vid Hissmoforsvattenkraftsstation : -Specifikt för aggregat G6 och G7
Jämtkraft AB which is a power production company in Sweden has bought two newhydro power units to their station in Hissmofors. The two new generators are using aconcept with sliding stator feet to handle the thermal expansion.The concept with sliding stator feet on hydro electric generators has not beenworking satisfactory on many hydro power stations in Sweden and has caused a lot ofcosts due to long downtimes.The new station in Hissmofors is very important for Jämtkraft AB, and therefore theywant to know how to make sure that the sliding stator feet are working as theyshould. According to theories and a simplified model of the generator the stator feetdisplacement should be around 1 -1,6 mm.The generators are delivered with a surveillance system that will measure thedisplacement of the sliding stator feet. The signal from the system isn?t accessible forJämtkraft AB but it will alarm when the sliding stator feet are malfunctioning.To secure the function of the sliding feet a logger for the surveillance system or adifferent measurement system must be used; if both systems are used Jämtkraft cansecure the function of the surveillance system..
Tidsberoende kvantkemiska beräkningar av optisk absorption hos polymerer och molekyler med litet bandgap
The vertical electronic excitation energies for the narrow-bandgap polymers LBPF, EP37 and EP62 have been calculated using Density Functional Theory (DFT). Also the vertical excitation energies for the acceptor unit of LBPF have been calculated using the Hartree-Fock (HF), DFT and Coupled Cluster (CC) methods. The calculations cover the visible and infrared wave length region and two strong transitions are obtained, one corresponding to the pi to pi* transition and one corresponding to the pi to Acceptor transition. The excitation energies obtained from DFT are below the corresponding experimental results and attempts have therefore been made to perform bench-marking calculations using a hierarchy of CC methods..
Validering av glidande statorfötter på Hissmofors G6 och G7
Jämtkraft AB has recently modernized its hydropower station at Hissmofors by replacing four older worn out units with two new units. The generators uses a concept with sliding stator feet to deal with the thermal movements that occur in the stator during operation when the unit is operating intermittently. At other sites, this method revealed shortcomings in the reliability. This has made Jämtkraft AB feel uncertainty about its function and therefore want to investigate it during an early stage. The generators have a built-in monitoring system for the sliding stator feet and by using data from there the function of the sliding stator feet has been investigated. The study focused on how the different stator feet move relative to each other and how the eccentricity and deviation from roundness changed during operation. The results show that there are several indications that the function of the sliding stator feet is not satisfactory.
Simulering av värmebehov för kombinerad kontors- och laboratoriebyggnad utan traditionellt värmesystem
In this Thesis the possibilities of designing a larger building that is very energy efficient in the sense that it would not need a conventional heating system are discussed. Solar radiation transmitted through the windows, internal heat from occupants, lamps and electric appliances inside the building and heat recovered from the ventilation system then have to be sufficient for the heating of the building. This study is of general interest since the property company, Akademiska Hus, plans to use this study as a first step in determining if this technique could be used in the future and thus be worth further investments. A building without a conventional heating system of the size investigated in this project has not yet been built.The energy needed for the heating of the building was simulated using VIP+.The conclusions from the study are that it is possible to build large buildings without any conventional heating system. This could be achieved in many different ways, for example by lowering the inside temperature or by using better windows and heat recovery system with higher efficiency.
Påverkan av skogsbrand på litiska arkeologiska fynd ? experimentell simulering av brand
This is a paper about the effects from smoldering fire on lithic objects from an archaeological view.
The introduction gives the background to this paper, a short orientation to forest wildfires and why the work is limited to: flint, quartz, quartzite and slate. Material and methods describes the stone materials and the setup that was used in the temperature logged tests with three replications for each type of material. The fuel in the burnings was peat on a bottom of sand. Flint showed a more drastic effect from heat compared with the other materials. Slate seems to have greater tendencies to change to darker colour and luster at lower temperatures than the other materials.