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1866 Uppsatser om Energy simulations - Sida 25 av 125
Uppvärmningssystem : Ekonomi, miljö och drift
This bachelor thesis aims at investigate how a specified house can optimize its energy consumption.Today the house often stands for the major part of the energy consumption in a consumers? life,whereas an energy optimization creates economic as well as environmental advantages. It is importantto make old houses more energy efficient, but putting high energy demands on new houses could beargued to be more important. The installations functions as both the heart and brain in a house, thusmaking it important to energy optimize these. Since the background describes the importance ofenergy efficiency and optimization in a house, the focus area of this report will be an investigation ofdifferent types of heating systems in order to be able to choose the one most suited for the house.Aspects considered when choosing the heating system was how economic the system is both inservice- and investment costs and how environmental and operational friendly the system is.Through literature reviews there were sufficient information gathered that served as a foundation whencomparing and choosing between the four systems - district heating, pellet-fired boiler, geothermalheating and solar heating.
Green Building : Ett företags energieffektiviseringsarbete i ett byggprojekt samt de krav som ställs för att få byggnaden Green Building klassad.
The examination has been performed at Bjerking AB, which is an architectural and engineering company. Bjerking AB has the ambition to be a member of Green Building.The Green Building program developed in year 2005 by The European Commission, the program is an environmental system with the aim to improving energy efficiency within the sectors of non-residential buildings. The minimum requirements to participate the program are following: in new-built buildings the calculated energy consumption must be 25 % lower than the requirements in the BBR (Building regulations) and in refurbishment the reduction must be 25 % lower than before the optimization.The aim of this study has been to examine and review the company Bjerking AB's energy efficiency work in the project of building the school/kindergarten S:ta Maria Alsike, where the goal is to get this building Green Building classed. A description of requirements to become a member of the Green Building has also accomplished in the thesis.The methods performed in this study are literature review, searches on the Internet, studies on the project database for facts/values, calculation of energy consumption and interviews of members of the Green Building. The following issues have been dealt with in the report;- Did the building in the project manage the requirement to achieve an energy consumption that is 25% lower than the requirements in BBR?- What technical measures/system was selected in the building?- What kind of cooperation was the project based on?- What is required for consultancy companies and real estate owners to become members of the Green Building?The study of the project and calculation of estimated energy consumption in the building, give the result 47 kWh/m2, year.
En kvalitetsanalys av EU:s direktiv om förnybar energi
There's no doubt today that mankind has contributed to the changing climate byher use of fossil fuels. This must change in the nearby future. The Europeanleaders are expressing concern that renewable energy sources are not beingused to their full potential. The 2001/77/EC Directive on Electricity Productionfrom Renewable Energy Sources was accepted in 2001 to encourage thedevelopment of energy production from renewable sources, which isconsidered a step towards the fulfillment of the goal of the Union, that 12% ofthe gross energy consumption should come from renewable energy sources bythe year 2010.The objective of this thesis is to illuminate the common legislation of the EUregarding renewable energy with regard to goal fulfillment, judicial quality,conflicts with other goals of the EU and other faults. The objective is reachedby a hermeneutic study in which interpretation of written text is the mainmethod.
FPGA baserad PWM-styrning av BLDC-motorer
This thesis work contains a litterature study about electrical motors in general and how PWM-patterns for brushless DC-motors can be made. A suitable method has been implemented as a simulation model in VHDL. A simulation model of a brushless DC-motor which describes the phasecurrents, torque and angular velocity has also been made. The motor model made simulations easier for the complete PWM-system. The design was synthesised and tested with a prototypeboard including a SPARTAN II FPGA.
Energiaspekter på gestaltning : fallstudie Energihuset i Uppsala
This thesis has been carried out at the Department of Urban and Rural Development at SLU Ultuna during the spring semester 2009. The topic of the paper is how energy consumption can be influenced through design and if the conditions for good design decreases when solutions based on energy efficiency are used. The report is divided into one literature study and one part where energy efficient solutions are used in a design. The thesis work has its origin in a project called "Energihus i Uppsala." The planned building will be a center for energy research in Uppsala. The project aims to demonstrate to the public what is currently happening in research related to energy.
Hydraulisk och termisk grundvattenmodellering av ett geoenergilager i Stockholmsåsen
Geothermal energy can be extracted from an aquifer, where the groundwater is used as heatexchange medium while heat and cold are stored in the surrounding material in the aquiferand to some extent in the groundwater. Application of aquifer storage for the use ofgeothermal energy is mainly used in large scale facilities and is limited to sites with suitableaquifers in the form of ridges, sandstone and limestone aquifers.Löwenströmska hospital in the municipality of Upplands Väsby, north of Stockholm, islocated nearby the northern part of the Stockholm esker. This means that it can be profitableand environmentally beneficial for the hospital to examine the possibilities of aquifer storagein the esker material next to its property.The purpose of this master thesis has been to investigate if geothermal energy storage with aseasonal storage of heat and cold can be applied within Löwenströmska hospital?s propertyarea using groundwater modeling. A hydraulic groundwater model was constructed inMODFLOW based on a simplified conceptual model of the groundwater system.
Skogsbränsleuttag vid förstagallring och dess påverkan på beståndsutveckling : simulering i Heureka med olika skötselprogram
Stands where pre commercial thinning has been ignored or inadequate often tend to have high stem density and low average diameter when they reach heights of thinning. In such stands, it can often be expensive to do a conventional pulpwood harvest as a first thinning. This study investigates the development of the stands and the economic outcome of forest fuel extraction, or a combined harvest as alternatives to the ordinary pulpwood harvest. Simulations in Heureka StandWise were performed for two thin and dense stands, which were constructed by data from the Swedish National Forest Inventory. The simulations show that the extraction of forest fuel in first thinning at an early stage can provide higher net revenue compared to conventional pulpwood harvest at the same time or later.
Bluetooth Low Energy som trådlös standard för hemautomation
Allmänheten har en stor efterfrågan av produkter inom området för hemautomation. Den senaste bluetoothstandarden Bluetooth Low Energy skapar nya möjligheter för intressanta produkter som underlättar vardagen. Lösningar som IR och Wi-Fi ger inte de förutsättningar som krävs för att på ett energisnålt och praktiskt sätt erbjuda sådana produkter, något som Bluetooth Low Energy gör. I denna rapport diskuteras standarden i syfte att redogöra för hur den kan användas för att automatisera ett hem.För detta examensarbete implementerades en strömbrytarprototyp och en iOS-applikation, vilka användes för att unders öka och påvisa ett koncept för hur tekniken kan tillämpas för hemautomation. Resultaten visar att teknikens räckvidd är dess främsta begränsning.
Värmeöverföring i bergvärmesystem : En numerisk analys av den ringformade koaxiala borrhålsvärmeväxlaren
The borehole heat exchangers of today suffer from poor thermal and hydrodynamic performance. The purpose of this thesis is to improve the performance of ground source heat pump systems and thermal energy storages by increasing the energy efficiency of the borehole heat exchangers. For this reason, the annular coaxial borehole heat exchanger (CBHE) has been analyzed. This type of heat exchanger is interesting in terms of both thermal and hydrodynamic performance. A model has been set up in the program Comsol Multiphysics in order to investigate the heat transfer characteristics along the borehole.
Modellering av manövercylindern för Nosstället på JAS39 Gripen
When models are used to describe physical phenomenon during development or modification of a technical system, it is often possible to reduce both the time needed and the overall development cost. With the use of models it is also possible to investigate the potential of the selected solution, without the need for any expensive details and testrigs. In many cases it is also not possible to test all the aspects regarding the functionality that are desired from the system, without using the complete and final product.In this case a model based approach has been used to optimize the different parameters in the new snubbing mechanism for the Nose Landing Gear Retract Actuator on the JAS39 Gripen.During the simulations, upper and lower boundaries were calculated for the length of the spring and the diameter for the restrictor. The governing constraints were given by the requirements for the retraction time during cold conditions and that the amplitude of the alternating loads in the uplock mechanism were brought to an acceptable level.The most promising results from the simulations were then used in a limited number of trials in the hydraulic rig to verify that the configurations comply with the requirements.The final parameters for the snubbing mechanism were chosen to 35±1mm for the spring and 0.4-0.5 mm diameter for the restrictor..
Konceptstudie av Waste Heat Recovery System på Tunga Fordon
In today?s fast growing and closely connected society, a reliable and energy efficient transportation system is more than ever desirable. Nowadays the significant part of the transportation sector?s energy demand is supplied by fossil fuels.Improving energy efficiency in combustion engines will result in reduction of fuel consumption and CO2 emissions. A modern internal combustion engine has an efficiency of 30-45 %, where the most energy loss occurs as result of heat losses in the exhaust and cooling systems.
The effect of new raw materials on pellet prices
As demand for renewable energy is increasing rapidly, the market for biomass pellets
is expected to continue to grow in the near future. Most of the new raw materials that
are discussed for pellet production have one thing in common; the production costs
will increase compared to using traditional raw materials such as sawdust and planer
shavings. The aim of this thesis is to investigate to what degree increased use of new
raw materials for pellet production will affect the general pellet prices in Sweden and
to survey what plans Swedish pellet producers have concerning new raw materials.
To investigate the raw material situation of the Swedish pellet producers an industry
survey was performed. Literature studies were also made on previous research in the
subject field. Calculations of the production costs for pellets were done for the raw
materials sawdust, wet sawmill chips and energy wood respectively.
New raw materials are already used by the large-scale pellet producers in Sweden.
Energimässig jämföelse med investeringskalkyl av två förskolor
This thesis includes an energy survey of the Herrgården pre-school, which has a modern heating- and ventilation system, and a comparison with Östers pre-school which has an older system. An energy survey of Östers pre-school has already been done by a group of three students and all the calculations and values have been collected from that survey. As of today, both pre-schools are heated thru district heating. It will be much easier to make smart and feasible energy-saving-measures by first conducting the energy survey.Herrgården pre-school in Gävle houses 81 children, therteen teachers, one cleaner and one cook. It was finished in the middle of 2009 and the staff has been very pleased with the in-door climate.
Påverkan på energianvändning och termisk komfort vid reglerinstabilitet
The purpose of the study is to investigate the possible effects of an unstable ventilation system and its influence on energy use and thermal comfort. The report also explores how qualified personal working with HVAC view and handles system control.In order to meet the requirements in energy efficiency and a comfortable indoor climate control regulation is a prerequisite. With optimized increased complexity of the climate systems, it becomes more challenging to control the system and the risk of unstable control increases. No previous studies about what affect an unstable system can have on energy use and thermal comfort have been found.The report is based on several tests were the controlling variable has been increased until the system becomes unstable. Two different types of unstable systems have been investigated.
Studie av integration mellan rategyron och magnetkompass
This master thesis is a study on how a rategyro triad, an accelerometer triad, and a magnetometer triad can be integrated into a navigation system, estimating a vehicle?s attitude, i.e. its roll, tipp, and heading angles. When only a rategyro triad is used to estimate a vehicle?s attitude, a drift in the attitude occurs due to sensor errors.