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3910 Uppsatser om Energy production - Sida 18 av 261
Pelletskvalitet : Test av olika råvarumixer i pelletstillverkningen vid Rindi Västerdala AB:s bioenergikombinat i Vansbro
Fuel pellets are a refined bio fuel mostly consisting of residues from sawmills and wood industry. At Rindi Västerdala AB's combined bio energy plant in Vansbro fuel pellets are produced, while the waste heat from the process is used for district heating. The pellets are produced from sawdust, wood shavings and dry wood chips that is dried, milled and pressed into small cylindrical rods. The advantage of refining the wood material in this manner is that the energy value is greater per unit volume and unit weight, thereby the cost of transportation per energy unit is reduced. Also, less storage space is needed.Pellet manufacturing is a complex process since many parameters affects the final results.
The state of the Latvian wood pellet industry : a study on production conditions and international competitiveness
In the last decade, member states of the European Union have adopted a range of measures to decrease the dependency on fossil fuels. This has led to an increased use of biomass in heat and power production. In some countries, the lack of forest resource has led to large scale power producers importing their biomass needs. Due to high energy content and homogeneity, wood pellets have become an internationally traded commodity used for large scale power production.
The Baltic States have emerged as one of the largest wood pellet exporting regions in Europe.
Osäkerhet i energisimuleringar av flerbostadshus : Analys av fem nybyggnationer
Since energy simulations are used to verify that projected residential buildings will reach the current energy requirements it is important that the results are reliable.This report investigates the extent of uncertainty in energy simulations, estimates the causes of the uncertainty and its economic and environmental consequences.The method used in this report is based on three validation methods; empirical validation, analytical validation and comparative validation. The analysis was carried out for five multi-family dwellings in Uppsala with installed meters for energy measurements. One of these objects, Klockarlunden, was studied in more detail than the others.The results show that the deviations are between 10 and 29% for the studied objects, which means that the uncertainty is estimated to be at least 29%. All simulations underestimate the buildings need of energy. The simulation for Klockarlunden can predict the energy consumption to be within the range of 46-98 kWh/m2year with 90% confidence level based on the current uncertainty.
Utvärdering och åtgärdsförslag av energianvändning i kontorsbyggnad
AbstractEmbla 5 is an office building which has done a large improvement. The clients of this building has made an order of WSP and the student Anders Kempe to calculate the use of energy for the building, and after that result proposing further measures which can decrease the energy use of Embla 5.The ground for this report is when calculation of the present energy use of the building is stated. To make that information of a number of parameters such as envelope, the heating system and ventilation has been located and set in to the simulation program IDA ICE which calculate the energy use.To improve the energy use further this project has been concentrated to change the system of ventilation. Today the ventilation system is of the kind CAV (constant air volume) and the air flow is dimensioned for after recommendations from BBR and Arbetsmiljöverket in the office spaces. Consider that Embla 5 is an office building where the people only staying for 8-10 hours/day so was the ide to see how much energy saving if the air flow is reduced the time people not being in the building.
Vision Nollenergihus : Energiförsörjning av passivhus med sol- och vindenergi
Climate change is the modern society?s common issue. The developed countries areconsuming more than what is sustainable, and the climate change due to the use offossil fuels can be seen clearly. EU has specified goals, in order to stop furtherdamage, which demand that every member state have to reduce its energyconsumption by 20 % before 2020 and 50 % before 2050, relative to 1995.The Swedish government uses a number of instruments to encourage reduction in theusage of energy, but every individual has to contribute to reach the goals.With increasing energy price the cost of living is going up. A lot of people are lookingfor ways to save energy and not be affected as much by the increasing price.Investments for insulation, replacement of windows and replacing old heating systemfor a new efficient heat pump is getting more and more common.This thesis is about investigating the possibilities in becoming independent from buyingenergy for households.
Energieffektivisering i flerbostadshus : En analys av ägarformens påverkan på arbetsprocessoch resultat
In Sweden the residential and commercial sector is a major user of energy, why the Swedish government has set a specific goal to half the energy usage in buildings by 2050, compared to 1995. The Swedish Energy Agency has therefore started the campaign ?Halvera Mera? to encourage demonstration projects that will show how to renovate in an energy efficient way, and in doing so prove that it is possible to reduce a building?s energy usage by half and still make a profit. These projects are intended to serve as good examples and give inspiration to residential owners to perform energy efficient renovations. To make sure that these projects serve their purpose, it is important to know what will inspire and what will impede a residential owner to invest in energy efficiency improvements.
GROT-transport från norra till södra Sverige
The European Council agreed in 2008 on a climate and energy package to combat global warming. This package is valid for each EU member country and means that greenhouse gas emissions must fall by at least 20% and the EU's energy use to 20%, consisting of Renewable Energy in 2020. The Swedish Government has set stringent climate and energy with the intention to set an example for the rest of Europe. For example, renewable energy sources account for at least 50% of energy use and our climate emissions to fall by 40% by 2020. A combination of these goals and a steadily rising oil price has led to an increased demand for wood fuel in the form of such branches and tops.
Tilläggsisolering - lönsamt enligt en livscykelkostnadsmodell?
It is found that the properties of the record years of 1965-1975 is leaking a lot of energy andthese properties are facing a major energy efficiency. From the energy aspect, the facade isafflicted with poor thermal insulation which is a big problem. To address this problem addinginsulation is a good alternative to reduce overall energy consumption of a building. Thewindows on these buildings are also a problem from the energy point of view. Therefore,there are many reasons considered for energy upgrading.
Energibalansen för ett nytt flerbostadshus i Mellansverige : Beräkningar intervjuer och analys av energikraven i Boverkets Byggregler
Abstract This degree project comprises 30 credits, i.e. 20 weeks of work. The work mainly deals with the energy balance for a multi-family house in Västerås and the requirements for energy conservation in the Swedish building code, BBR. Calculations of the energy balance are supplemented by a number of interviews. Energy conservation in general has become more important in recent years and the subject is in line with increased public awareness. This importance and attention is explained by environmental problems in general and global warming in particular, but also by rising energy prices.
Energieffektivisering av modern tillbyggnad till äldre skola : fallstudie från Österbyskolan i Österbybruk
The Swedish government has introduced a goal to reduce the energy intensity by 20% to the year 2020. To reach this goal actions need to be taken throughout the energy sector which includes residential and commercial buildings. This thesis considers the possibility to reduce the energy usage in a building located close to Uppsala. The analyzed building is a combined office, cafeteria and entrance and was completed about half a year before this project started. Therefore the measures presented for a more energy efficient building are presented as measures for future constructions.Simulations have been made in VIP-Energy, a dynamic energy calculation program.
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.
Artificiella sötningsmedel i dryck och dess effekt på hungerkänslor och energiintag
Sahlgrenska Academyat University of GothenburgDepartment of Internal Medicine and Clinical NutritionAbstractTitle: Artificial sweeteners in beverage and their effecton hunger and energy intakeAuthor: Sofia Andersson and Sofia JakobssonSupervisor: Heléne Bertéus ForslundExaminer: Anna WinkvistProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: April 11, 2012BackgroundIn 2010 the total consumption of soft drinks in Sweden was estimated to 69 litres per person and17 % of the domestic production was estimated to consist of soft drinks sweetened with artificialsweeteners. The effects of artificial sweeteners on hunger is not yet fully understood. It isspeculated that they might increase hunger and hence increase energy intake.ObjectiveThe aim was to compile the evidence regarding the effects of an intake of a beverage sweetenedwith artificial sweeteners compared to sucrose on subsequent hunger and energy intake.Search strategyA systematic search for literature was performed in the databases PubMed and Scopus.Selection criteriaThe inclusion criteria were RCT, human studies, articles published in Swedish or English, studieson healthy adults and studies measuring hunger with a subjective scale or energy intake. Theexclusion criteria were studies who measured energy intake under other forms than standardisedor controlled, studies without a standardised dose of the beverage and articles needed to beordered against payment.Data collection and analysisFour articles were selected and examined according to a template developed by SBU. Theevidence for each outcome was weighed together and graded according to GRADE based on asummarised evidence form developed by the Sahlgrenska Academy.Main resultsAll four articles measured subjectively rated hunger.
Hållbara projekteringsverktyg : Från byggnadsinformationsmodell till simulering ? en utvärdering av Revit och Virtual Environment
This study examines the use of building modeling and energy simulations in the design process of a building. The take-off point is the notion of energy simulations being needed early and throughout the building design process, and that the lack of energy simulations may be explained by the fact that they are time consuming and therefore often too expensive. A greater interoperability between software tools used by relevant disciplines, such as the architect and the energy specialist, would create smoother workflows, which would reduce this cost and open up for more frequent and iterative energy simulation processes. The study is an assessment of the modeling tool Revit and the simulation tool Virtual Environment and whether they can create smoother workflows, and make leeway for a more frequent use of energy simulations throughout the design process. It also investigates the limitations of what can be examined by simulations in Virtual Environment. This will hopefully help clarify the future role of energy simulations in design processes. The method is a trial by error approach of testing the two software tools by building and simulating a model. The results of these tests show that the workflow is not optimal (and therefore time consuming) for frequent and iterative simulations throughout the design process, but it also reveals some great possibilities of what can be performed with these two powerful tools at hand. Further development with regards on platform independency of the building information model, including seamless exporting and importing, seems necessary to strengthen the future role of energy simulations..
Utvärdering av AOT för ett pilotskaligt, recikulerat akvakultursystem för fiskodling
With the climate change issues growing in importance on the social agenda, the field of urban masterplanning is of no exception when it comes to minimizing the carbon footprint in a variety of projects. The aim of this thesis has been to prepare the Carbon Critical Masterplanning tool, a software plugin for carbon dioxide emissions assessment developed by Atkins, to be used in Swedish conditions. The main targets were to improve the areas of the tool associated with energy conversion and renewable energy sources, and to test the tool in a real case. A planned construction of a new campus in Albano, Stockholm was chosen for the pilot study. A 3D model was built in the tool and the carbon footprint was calculated for a variety of combinations for energy supply to the future area.
Energieffektivisering genom förvärmning av flis till kokare med sekundärvärme
The Swedish pulp and paper industry meets higher demand for energy efficiencyi mprovements with increasing energy prices and changes in the Swedish renewable energy certificate system. One action of energy efficiency improvement is by using secondary heat, that otherwise would have been treated as waste heat, for use in a system with lower temperature demands. The aim of this Master´s thesis is to identify possible secondary heat sources in a typical Swedish pulp and paper mill and to investigate what economic benefits the secondary heat will provide when being used for pre heating of wood chips to a kraft digester.The Master´s thesis focuses on three secondary heat sources; dry warm air, warm water and moisture saturated warm air located inside the pulp or paper mill. Two types of kraft digesters are simulated within this study, a typical Scandinavian digester and a modern twin vessel steam phase digester.Due to quality aspects and low temperature level drying is the drying technology with dry warm air rejected. Using warm water in direct contact with wood chips increases the quantity of water to the evaporation plant and thus reduced pulp or paper production and is therefore also rejected.