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2137 Uppsatser om Energy calculations - Sida 43 av 143

LCA av dricksvattendesinfektion : en jämförelse av klor och UV-ljus

Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods.

Beräkning av koldioxidutsläppet från bostadssektorn i Stockholms län

During the last decades the housing sector has increased continuously, and housings and services accounted for 40 % of the energy usage in Sweden during 2011. The expansion in number of buildings in society has resulted in an increase in both energy usage and emissions of greenhouse gases. It is crucial to enable a sustainable development of society and as a result, the demand to reduce the emissions of carbon dioxide is a current question. In this study, the carbon dioxide emitted from the housing sector in Stockholm is estimated. The housing sector can be divided into different types of houses such as apartment blocks, single-family houses and holiday houses. By collecting information of the energy purchased in respective households, a computational model is generated that calculates the total emission of carbon dioxide.

Turbinkretspump system - Kraftvärmeverket i Borås

The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.

Eurocodes : Beräkningsjämförelser mellan eurocodes och BKR

In the year 2010 a transition will take place here in Sweden from the present rules how to dimension buildings in to the common rules with have been developed in Europe, the Eurocodes. Eurocode is the term for a collection standard that contains calculation rules in how to dimension constructions and buildings. They are developed by the European standardize committee.The purpose with this examination work is to get an insight of what changes this will contribute to, and how it will affect the dimensioning. Are there going to be any differences in the dimension you finally chose?To investigate these possible differences two constructions will be calculated first in the present Swedish rules, and then in the coming eurocodes.One of these two constructions will be build completely in steel, while the other will be build completely in concrete.

Torrefaction of biomass : a comparative and kinetic study of thermal decomposition for Norway spruce stump, poplar and fuel tree chips

Stump biomass is energy rich and stump harvesting for use as fuel become more and more interesting in Sweden. Swedish Forest Agency (2009) has estimated that stump harvesting in Sweden would respond to an annual energy supply of 57 TWh/year. However, stump has not been recognized as a bioenergy resource in Sweden. Suitable methods for pre-treatment of stump are probably of great importance to make it accepted as fuel. It is therefore rewarding to carry out an investigation in this area for stump. This report represents results from a diploma project, which was aimed to develop a fixed bed reactor for experimental study of biomass torrefaction, followed by TG analysis and kinetic modelling employing Ozawa method and different kinetic models including one-step and three-pseudo-component models.

Systemanalys av skogsbränsletransporter :

At the end of 70s and the beginning of 80s, 18 terminals was built and used for chipping wood residue from clear cuttings. Most of the terminals was terminated before the 2000s but with the high oil- and energy prices that we can see today there might be a place for these terminals again. The goal with the study was to analyze and compare economical differences between 5 different logistical systems, collected data was used with a set of formulas. The systems include long range transport of slash, chips and bundles. Three of the systems include transport by lorry to industry the last two includes a terminal with access to train transport.

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.

Byggnadsintegrerade solcellssystem : Solceller som byggnadsmaterial

This thesis aims to identify the building integrated photovoltaic solutions available in the market with respect to general pros and cons of different systems and a technical description of there attachment system. Investigate and provide examples of various building integrated photovoltaic solutions in Sweden and describe the experiences and results of these projects.The methods used to obtain relevant information are interviews with individuals involved in significant projects and a thorough search of different solutions from solar suppliers.The conclusion is that solar energy is needed for a sustainable society. There are endless opportunities regarding BIPV, with many companies with different products and individual solutions. But so far it?s not so customary in Sweden.

Löpmagsförskjutning hos mjölkkor : en besättningsutredning för att identifiera riskfaktorer för metaboliska störningar

The purpose of this study was to find possible explanations to why the studied herd had an increased incidence of abomasal displacements. The incidence of abomasal displacement in the herd was three times higher than the incidence of an average Swedish herd. The cows in this study were fed a total mixed ration. The different parameters studied were: energy content in food, nutritional content in food, body condition scoring, concomitant other diseases, and blood parameters of glucose, fructosamine, cholesterol, insulin, betahydroxybutyrat and free fatty acids. The author?s suggestions to decrease the problems are to decrease the energy content in the TMR to lower the cows? body condition scores in the dry period and changing the content in the TMR to increase the amount of NDF and adding structure in the form of chopped straw.

Kombinerat system för ventilation och rumsuppvärmning : Parameterundersökning i simuleringsmodell för takvärmesystem

A large amount of our time is spent indoors in an artificial climate. To make the experience pleasant there are requirements on the ventilation and the heating system. At the present time the most common form of heating is a radiator system complemented with a ventilation system. A ceiling heating system with combined heating and ventilation can replace the two separated systems. The benefit with a ceiling heating solution is that it saves space since the radiator system is no longer needed.

Limträstomme till hallbyggnader : Utformning och dimensionering av momentstyva ramhörn och 3D-modell framtagning

Industrial buildings are increasing all over Sweden. Farmers are building new modern facilities and the government chooses to build new halls to invest i youth sports. Glulam is the most common framework but there are limitations because of the transport. Therefore, there is a need to develop new solutions to increase the use of glulam.The maximum torque in the eaves was found in the frame with a roof pitch of 18 degrees and a wingspan of 25 meters. Using hand calculations according to Eurocode and comparison with the computer software StatCon, the maximum torque, shear force and utilization rate is calculated.

Försäljningsorganisationen Stjärnägg : en utvärdering ur ett leverantörs och ägarperspektiv

Stjärnägg is a sales organization operating on the Swedish eggmarket, owned by nine Swedish packing companies. Those nine packing companies are not just owners of the sales organization, but at the same time competitors since they compete in the market when they do not sell the eggs through Stjärnägg.The purpose of this thesis is to evaluate the sales organization from a supplier and owner perspective. To answer the purpose of this study, qualitative interviews have been conducted with the owners of the egg packers. This has been done in order to get as fair picture of the sales organization as possible. From the answers of the interviews, a compilation has been made to be able to give Stjärnägg concrete proposals of improvements in the organization.

Krafter på rörsystem vid transient flöde : En jämförelse mellan RELAP5 och Fluent

At Forsmarks Kraftgrupp AB (FKA) forces on pipe systems due to transient flow are frequently calculated as a step to verify their structural integrity. In nuclear industries these forces are often calculated with a one dimensional thermal-hydraulic analysis-code called RELAP5. When calculations regarding more complex geometries are needed, the three dimensional code Fluent is often used. This code is highly time consuming and requires large computational power.This projects aim is to compare calculations of pressure, flow and forces carried out by RELAP5 and Fluent for an arbitrary pipe section during transient flow conditions. This has been accomplished by constructing a simple geometry for which a transient flow is simulated in both programs.

Upptäcka matematik utomhus : Vilket förhållningssätt till matematik utomhus har förskollärare som inspireras av olika pedagogiska inriktningar och hur beskriver förskollärarna att de arbetar med matematik utomhus?

This project investigated the current market regarding wireless net and the communication between the tools used for diagnostics/maintenance and an embedded system. Based on documentation obtained through interviews a demo system was created based on Bluetooth Low Energy (BLE) communication between an embedded system and an Android device.This report intends to describe the tools and methods used in the design of the demo system and the result of an analysis of the BLE communication.Bluetooth Low Energy is an exciting protocol with wide applicability within the industrial field. This project investigated the communicational possibilities between a Smartphone and a Raspberry Pi and based on the results that emerged the conclusion can be drawn that BLE is a protocol with many beneficial applications within industrial IT..

Wii Sports och Sport : En jämförelse av fysiska och emotionella skillnader och likheter i träningsspel jämfört med riktig träning

AimThe purpose of this study is to compare the level of activity between playing wii Sports Tennis and wii Sports boxing, and the usual sports, and to see how the two variants are perceived.Issues:- How much strain ratio and energy consumption it gives to exercise wii sports compared with the playing of sport for real?- How do the test participants experience the different tests?- How are the two wii sports games against each other in terms of activity and fitness in the school environment?MethodThis is an experimental study in which 10 test participants (5 men and 5 women) have carried out four different physical tests. The tests consisted of either playing an exergame or playing a sport for 25 minutes. Physical activity was measured during the test using a heart rate monitor. All test participants completed all tests in the same order.

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