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957 Uppsatser om Thermal heat losses - Sida 17 av 64

Renovering av miljonprogrammet till Umeå kommuns nybyggnadskrav för energianvändning

A lot of houses built during the Million Homes Programme are in need of major renovation. Today?s technology and materials are better than in the 60?s and 70?s. Both Swedish government and the European Union have set climate goals regarding energy consumption by 2020 and 2050. Achieving these goals would require better standards in buildings than the Building regulations demands, such as Umeå municipality?s construction requirements for new buildings.The report aims to investigate if a renovation of apartment buildings from the Million Homes Programme can reach Umeå municipality?s construction requirements.

Vädrets påverkan på byggarbetsplatsen

This exam report contains studies about how the weather affects the construction site from a planning and productivity perspective. In 1960?s the contractors started to build during the winter, since then the demands to obtain a good construction has been higher on both the contractor and then promoter.In this report you will see how the different actors at the construction site handle the weather problems. By several interviews of the actors at the construction site there have been opinions about the weather situation which has been collected. To get a wide perspective of the problem, field studies from four different construction sites been made.Weather statistics over Halmstad is a mayor part of this report.

Två presentationstekniker för grafer : deras styrkor respektive svagheter inom en bioinformatisk kontext

This degree project has been carried out in cooperation with Enertech AB in Ljungby and is pilot study to automating all current manual soldering. The soldering process accounts for a large part of the processing cost in the production of a heat pump. The process is also a quality risk and has a major impact on the lifetime of the final product.The Main task of this project has been to evaluate automation of the soldering process, to develop automation solutions and a principle layout, to draw the design changes required for the automation and to calculate the supposed solution.This pilot study has resulted in a suggested automation solution using laser as a heat source for soldering. Calculations of the solution show that a automating a laser soldering cell is very profitable..

Vidareutveckling av PV/T-receiver för koncentrerat solljus

The rising demand for electricity and heat raises a big challange for the society and engineers. Many products have been introduced to the market to supply more energy to the energy systems. Absolicon AB is a Swedish company that develops and markets a combined heat and power generating product. The product, Absolicon X10, uses a parabolic trough to concentrate the radiation of the sun onto a receiver. The receiveris equipped with mono crystalline solar cells and is cooled by a circulating liquid media.

Vinn/vinn - eller svinn? En studie om hur livsmedel kan doneras till välgörenhet istället för att kasseras

Ungefär en fjärdedel av den klimatpåverkan som de svenska hushållen orsakar kommer från maten vi äter, eller närmare bestämt från de utsläpp av växthusgaser som maten ger upphov till på sin väg från jord till bord. Om maten slängs innan den konsumeras har denna miljöpåverkan skett i onödan. Uppsatsen undersöker VIS (Välgörenhet Istället för Svinn), en svinnåtgärd där fullvärdiga livsmedel istället för att slängas, skänks till välgörenhet. Målet är att undersöka hur VIS fungerar, samt att bidra till ökade kunskaper om detta för Sverige nya sätt att bemöta svinnproblematiken. VIS styrkor och svagheter, liksom de hot och möjligheter som kan finnas, har undersökts med hjälp av en SWOT-analys.

Biogas till kraftvärme på Wapnö : en projektanalys utifrån ett företagsekonomiskt perspektiv

Biogas is a gaseous fuel, rich in methane, produced through a biological route in an anaerobic digester. A gas engine generates combined heat and power, which can be used at the farm to reduce energy cost. The process also generates a digestate, with better utilization of nutrient compared to cattle manure. The aim of this study is to analyze the profitability of a farm-scale biogas plant for combined heat and power (CHP) at Wapnö. Wapnö is an agriculture company located in the southern part of Sweden.

Värmeväxlare med luftkonditionering för tvättstugor

The energy in laundry rooms, in form heated air, can be utilized with a heat exchanger. A concept and an early prototype of the heat exchanger have already been developed to show that the theory works. This report describes the continued development and construction of the product.A field study was made in order to investigate the environmental usage and establish the product design. The most common washing machine was used as a calculation model, and calculations were also made to estimate the amount of energy in the air. A previous analysis of the existing prototype is also presented in this report, to show the products potential capacity.

Effektiviseringsåtgärder i tryckluftsystemet hos Vattenfall Värme Uppsala

In this work an assessment of the compressed air system in the facilities of Vattenfall Heat Uppsala has been conducted. The facilities constitutes, among others, a combined heat and power plant, and two waste incineration plants. The compressed air is supplied primarily by seven rotary screw compressors and yearly electric energy consumption in these has been determined. Furthermore, the usage of compressed air has been mapped in order to find processes with energy savings potential. Several suggestions how to reduce the usage of compressed air have been presented, resulting in decreased need of electric energy and reduced CO2-emissions.The results show that total need of electric energy in the compressors, during a standard production year, amounts to 5.83 GWh.

Utvärdering av laddningskoncept för lastbilsbatterier

When drivers overnight in the truck lots of electric energy is consumed by heaters, fans, lights and other extra equipment. If the engine is not running, this energy is taken from the lead/acid batteries of the truck which then needs to be recharged during operating hours. The fact that the charge acceptance of the lead/acid batteries is dependent on the temperature makes it hard to fully recharge the batteries at lower temperatures. A negative charge balance can lead to starting problems within a few days use in cold climate.In this thesis work, the effects of different battery charging concept are evaluated on the most common Scania battery (175Ah). A battery model is implemented in Matlab and some simulations of charging are made.

Energieffektivisering i flerbostadshus för studentboende

Uppsalahem AB is a municipally owned real estate concern that owns and administrates housing for nearly 30 000 people. The company puts a lot of effort into reducing the energy use of their housing stock. This project is a master?s thesis in the energy systems programme at Uppsala University, carried out in collaboration with Uppsalahem. The aim of this thesis is to provide energy saving measures for fourteen student housing buildings in Uppsala, Sweden.

Are changes in heart rate and/or arborisation of vaginal mucus useful parameters for detecting heat in heifers? :

The milk production per cow has increased considerably during the last 50 years and due to the breeding for higher milk production also brings decreased reproduction efficiency. In a Swedish study 1996 it was shown that on average only half of all estruses were detected. Every time a farmer fails to detect oestrus it costs the farmer about 1200 Swedish crones and the need of means of detecting oestrus is therofore large. With this study we wanted to investigate if heart rate respectively crystallisation of vaginal mucus (arborisation) could be useful means of detecting oestrus. We monitored two oestrus cycles in four heifers.

Detektor på skördare för utsortering av träd med metallskrot

Fortifikationsverket which is the landlord for the Swedish national defence has a great problem in their forestry due to the relatively large amount of metal objects in their timber. These metal objects cause different types of economical losses in the timber refinement chain. To enable out sorting of logs containing metal objects already in the harvesting phase, Fortifikationsverket is interested of the possibility to utilize some type of metal detector in a harvesting head for that purpose.The goal of this study was to, with help of a case study, enlighten the problem that metal objects in timber cause for Fortifikationsverket and their customers of timber and to investigate conditions of to mount and utilize some kind of metal detector in a harvesting head at present.The saw timber deliveries by Fortifikationsverket during the time period 2003-2005 was used as a reference volume for calculations of economical losses. In this case study was included two sawmills where timber from Fortifikationsverket were delivered to for further refinement. Factors investigated were the type of damage metal objects caused in these two sawmills and the economical signification of these damages.

Framtidens Hus

The company Sol & Energiteknik wanted to examine the possibility to make a standardhouse totally energy independent. Based upon this I have, during the spring of 2007,examined the possibilities available at the market today through litterature studies, contactwith several companies and reading reports at the internet.The first thing to examine has been to determine the energy consumption for a standardhouse, and find out if there are better technologies to be used for energy conservation.My conclusion in this matter is that there are possibilities today for building a house moreenergy efficient.When I had reached the point at which my design for the house was decided, I also hadto choose the different products to use to produce energy as well as to store that energy.To produce heat and electricity to the house I decided to use a wind turbine and a solarwater heater.The most difficult part of designing a house that is energy independent is that theproduced energy must be stored somehow. Storing the heat is relatively easy beacuse theheat can be stored in a large water tank. The electricity is a bigger problem beacuse itmust be stored in batteries, which today are too expensive to be used in a standard house.In the future producing and storing hydrogen might be used to produce electricity, buttoday that technology is both expensive and not tested enough.My final conclusion is that a standard house can not be built to be totally energyindependent today, unless it is very expensive to connect the house to the electricitynetwork. As an alternative solution I came up with a proposal for a house which isconnected to the electricity network and have some amount of own produced energy.This house prooved to be a good investment if you choose to build it today, and it couldbe a very good investment in the long run beacuse energy prices increase every year..

Phosphorus in agricultural soils around the Baltic Sea : comparisons of different laboratory methods as indices for phosphorus leaching to waters

Eutrophication of the Baltic Sea is a serious problem. A major contributing factor is diffuse losses of phosphorus (P) from agricultural land in surrounding countries. In order to estimate P losses, environmental monitoring of small agriculture-dominated catchments is being carried out in most of these countries. Evaluation of the risk of P leaching to waters is usually based on chemical tests originally developed to quantify the amount of soil P available for plant production. The tests are performed in different ways in the different countries and a number of different extraction agents are in use.

Underlag för BREEAM-certifiering : Kristianstad Nya Galleria

The company Olofsfors AB manufactures drive belts for forest machinery, known as ECO-Tracks, and abrasion-resistant steel and cutting edges for graders, excavators and tractors, known as Bruxite and SharqEdges. Manufacturing these products requires the steel to be heated and molded, then submerged in water and hardened. The water used in the hardening of steel is pumped to the process from pits below the floor and then pumped back to the pit after it?s been used. Since the temperature of this water rises after being used to harden the steel the temperature of the pumping pit needs to be adjusted to maintain its setpoint of 21°C.

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