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809 Uppsatser om Passive heat - Sida 9 av 54
Energianvändning i serverhallar: energiflöden och kylning
This thesis examines different methods for the cooling of data centers. Several means of cooling with the refrigeration cycle have been studied, as well as the feasibility of using free cooling in different parts of Sweden. In addition, the possibilities of transferring excess heat to a nearby district heating system were investigated. It was found that in all investigated cases except two, the data center could be cooled solely with free cooling for at least 300 days a year when only the outside air temperature was considered as a constraining factor. The limit was then set to 20 °C.The vast majority of all district heating systems in Sweden get little to none of their heat from other excess heat sources.
Vitvarueffektivisering med hjälp av värmelagring : Simuleringsstudie kring energiförsörjning av vitvaror med hjälp av värmepump & ackumulatortank
The constant need of energy is something that affects us all no matter our current situation. Whether we are driving our car to work, taking the elevator or using the oven to cook dinner we end up relying on energy. Our whole society is continuously striving to achieve a higher grade of efficiency and the process of supplying ourselves with energy is no exception. The importance of appliances in our everyday life cannot be exaggerated and thus the importance of their high efficiency.Efficiency is already a keyword in the appliance industry with labels, stars and numbers helping us choosing the most suitable option for the task ahead. No matter how efficient appliances often use pure electricity as their energy source.
Resurseffektiv livsmedelsproduktion : Tillämpning av industriell symbios för ökad resurseffektivitet inom den svenska tomatodlingsbranschen
Industries with energy costs as a large proportion of their total costs are greatly affected by the instruments deployed to cope with the Swedish climate and energy policy goals. With energy costs representing more than 30 % of the total costs, tomato cultivators are one of the affected industries. In order to remain competitive with other countries, a more resource- and cost-efficient cultivation of tomatoes in greenhouses is desirable in Sweden. Based on the concept of industrial symbiosis, this study investigates the prerequisites for a resource-efficient production of locally grown tomatoes in Sweden through the utilization of low grade industrial waste heat. The study is based on the foundry industry as the supplier of waste heat.To investigate the environmental, technical and economic potential of the exchange of waste heat, a comparative life cycle assessment, an inventory of the supply of industrial waste heat in Sweden, a compilation of potential technologies for the recovery of low grade industrial waste heat for heating greenhouses and a comparative life-cycle cost calculation were carried out.
Gränsen mellan aktiv och passiv försäljning. En analys av konkurrensreglerna på marknaden för anläggningsmaskiner
The essay focuses on the blacklisted restriction of passive sales in the block exemption to Article 101 TFEU on vertical agreements. It confirms the authors' thesis that the distinction between active and passive sales do not cause any problems in the theory, but that the reality shows the opposite. The analysis further shows that more detailed guidelines probably would not solve the problem but rather it is the objectives behind the rules and practice that causes confusion.The essay questiones whether the changes in the new guidelines for the block exemption also involves a change in the Commission's approach to the restrictions on passive sales when the same purposes as before lies behind the rules, where the goal of an integrated market is the most important. The impact of the so called "economic approach" within practice since the 1990s, when it was first introduced, suggests that changes are slow. The essay requests a greater openness to the fact that the realization of a single market and the desire to move closer to the commercial reality of companies collide.One proposed solution is given, where the rules would be designed so that 'absolute territorial protection' is prohibited, contractually and de facto, and that it is left open for companies to determine if their actions lead to this.
Lågtempererad fjärrvärme i Umeå
People in today?s society are becoming more and more aware of how important it is to use energy as efficiently as possible. This is clearly noticeable by an increase in home produced heat with e.g. solar panels or heat pumps heating systems. These changing customer demands forces district heating technology to be redesigned, which is why there is an ongoing research regarding the next generation of district heating - low temperature district heating (LTDH).
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.
Projektering av ett småhus samt ekonomisk jämförelse av värmesystem
Design of a house requires knowledge of both technology and economics. Heating and ventilation shall be designed, costs are calculated and estimated and requirements must be fulfilled. Which heating system is to be elected is also a difficult choice, especially with rising energy prices as a factor.The choice of energy system is not always given, because it depends on several factors. Below is a comparison between district heating, geothermal heat pump and electric boiler from an economic standpoint. In a previous report appears district heating and geothermal heat pump as the best options.
Att ta vara på solens fulla uppvärmningskapacitet
The purpose of this bachelor´s report is to expand the knowledge about heat supply of a small house in Malmö. The heat supply will be provided from solar panels in combination to two accumulator tanks which will storage the up heated water and a pellet boiler.The technique used here is warmth storage in water over seasons, which will provide the total need of heating for the house. Accumulator tanks in combination to solar panels gets more and more common in Sweden but this far it´s unusual to use it for storage over seasons. This report will highlight many of the difficulties associated whit heat storage and give information about a system's possible design and function.The design of this system is decided early on. An accumulator tank is placed 2 meters down in the earth on the backside of the house.
Biogas på Wapnö : Analys av framtida energisystem
Considering that the price and demand for energy gradually has risen over the past decade and a wider discussion about the human impact on the environment has become increasingly more important and given a clearer role in modern society. This has contributed to increased incentives to reduce the use of fossil fuels and increase the use of renewable energy.The agriculture currently accounts for 20 % of Sweden's total greenhouse gas emissions. A way for an agricultural company like Wapnö AB to reduce their emissions could be to utilize existing renewable energy sources within their own premises.The report's aim is to create an energy audit of Wapnö?s existing energy system and how it changes with a future biogas plant in operation. The energy audit is used to illustrate how the company?s climate footprint could change.
Energikartläggning av biogasanläggningen, Kungsängens gård
The purpose of this thesis was to make an energy survey and quantify energy flows of individual unit operations associated with the biogas production in Uppsala Vatten och Avfall AB:s biogas plant, located at Kungsängens gård. Moreover, large consumers of energy would be identified and analyzed. The objective of this energy survey was to obtain a detailed understanding of the energy use in the biogas production.The energy survey was divided into two parts: electricity and heat. Each part was treated separately and with somewhat different approach. To estimate the electricity usage during the projcet the rated power of each selected unit operation was noted and multplied with thenmeasured time of usage.
Energikartläggning vid biogasanläggningen, Kungsängens gård
The purpose of this thesis was to make an energy survey and quantify energy flows of
individual unit operations associated with the biogas production in Uppsala Vatten och Avfall
AB:s biogas plant, located at Kungsängens gård. Moreover, large consumers of energy would
be identified and analyzed. The objective of this energy survey was to obtain a detailed
understanding of the energy use in the biogas production.
The energy survey was divided into two parts: electricity and heat. Each part was treated
separately and with somewhat different approach. To estimate the electricity usage during the
projcet the rated power of each selected unit operation was noted and multplied with the
measured time of usage.
Förebyggande av hypotermi under narkos på hund och katt: vad görs på svenska djursjukhus idag, och vilka evidens finns för olika behandlingsmetoder?
Hypothermia during anaesthesia is a well-known phenomenon that may cause several side-effects such as greater risk of postoperative wound infection and increased risk of heart complications. The most efficient way to avoid this is to prevent hypothermia from occurring. The aim of this paper was to compile the research on the most efficient way to prevent hypothermia during anaesthesia for cats and dogs, and to compare these results to how Swedish animal hospitals prevent hypothermia today. To investigate this, a survey was sent out to several animal hospitals around Sweden to see what methods they used to prevent hypothermia in their clinics.
It is difficult if not impossible to prevent the body temperature from falling slightly when anaesthesia is induced because of the drug interactions in the body that follow from the drugs given. A 1-1,5°C decrease in body temperature is to be expected and is difficult to avoid.
Prestandaförändringen hos en bergvärmeanläggning efter fem års drifttid
The aim of this report was to do a case study at a geothermal heating system which has been in operation for about 5 years, and study if its performance has changed during this period of time. A literature study about the processes involved was also done in purpose of background knowledge.The tenant-owner?s association Duvan at Petterslundsgatan in Uppsala installed year 1999-2000 a geothermal heating system. The purpose of this installation was that they hoped it would lead to a smaller usage of district heating which would lead to a reduction of the heating expenses for their buildings. The geothermal heating system consists of 19 energy wells and 4 geothermal heat pumps, and it is one of the first systems of that size in the region of Uppsala.
Effektivare energianvändning på Totebo AB
The main goal with this thesis report was to come up with ideas of how to make the use of energy more effective and thus save money for the company.First a survey was made to find out where and how the energy consumers were divided within the company. The results were then used in calculations to find out how much money that could be saved and how long it would take to get back the investments.There is a big potential in saving money by recovering heat from the UV-lamps with a heat exchanger. It would also even out the pressure in the factory which is a source to heat loss and a cause for discomfort amongst the employees. It?s possible to save 105 000 kr in a year and the money needed for the investments is 600 000 kr.By using the recovery air more effectively the company could save up to 250 000 kr a year in lowered heat purchases, but this would require the use of automatic dampers.If you reschedule the running times for the wood chipper and invest in some kind of load management, for example Sydkraft?s ?Energidirigent? you can save at least 42 000 kr.
Beräkning av värmeförluster och energieffektivisering av elbussar
The ?civilized? world is in need of fossil fuel in order to function. Hybricon AB is a company in Umeå that is developing a technology that hopefully can reduce parts of this need. They are currently testing their two electrical busses (with Hybrid backup) in city traffic on the roads of Umeå in cooperation with the county of Umeå. The busses are originally diesel-busses, but the diesel motor has been replaced with two electrical hub-motors with a power of 145 kW each that are powered by batteries.The batteries are charged at the end station after each route. In case the batteries should run low on capacity during driving, they can be recharged by the so called genset.