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2463 Uppsatser om Energy efficiency - Sida 24 av 165

Jämförelse av frånluftsvärmepumpar

In order to reach the environmental targets, set up by the EU, there are many measures taken to make Sweden more energy efficient. In the housing and real estate sector, an installation of an exhaust air heat pump that reuses the heat in the exhaust air in order to lower the amount of acquired energy, is an example of such an action. The recovered energy can then be used for heating of radiators and tap water. This report aims to evaluate and compare three different systems using exhaust air heat pumps regarding COP, degree of coverage and cost savings. This study was delimited to only account for apartment buildings.The theory chapter describes the different conditions and factors that affect a building?s energy balance.

Kvalitetskontroll av trafikmätningssystem ? En studie om noggrannheten hos induktiv slinga, slang, KomFram, video och radar i olika trafikmiljöer

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Analys av hur byggnadens höjd påverkar energiförbrukningen i flerbostads- och kontorshus

This diploma work has been carried out in collaboration with the building contractor Sh Bygg Fastighetsutveckling AB in Uppsala with the intention to investigate how the height of a building affects various energy aspects such as transmission losses, infiltration, and the specific energy usage. Three different reference objects have been studied. The reference objects have been simulated for four different heights in the calculation program VIP-Energy.The results show that an increase in floor number can lead to both advantages and disadvantages. As the number of floors increases, transmission losses per square meter floor area decreases. However, as the height of the building increases, the reduction rate decreases.

Elevers uppfattningar om kunskap, motivation och undervisning kopplat till SO-ämnena

The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.

Korsplattformskommunikation med Bluetooth Low Energy

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..

Skogs påverkan på vindkraftsproduktion - en fallstudie av vindkraftverk vid Andersfält.

The purpose of this master thesis is to investigate how nearby forests affect the energy production in wind turbines. To reach the purpose a case study is performed on three wind turbines sited on a field in a north-south line at Andersfält in the municipality of Halmstad, Sweden. Approximately 100 meters south of the southern wind turbine a forest is situated. The case study is divided into three sub studies where the difference in energy production, the affect of the forest and a wind meteorology model, WAsP, is studied. The result show that the forest have a significant influence and that the WAsP-model gives an incorrect result of the energy production in wind turbines sited near a forest..

Energianalys av MVG-gallerian, samt en jämförelse av beräkningsprogram

På uppdrag av Sweco Systems i Umeå har detta examensarbete utförts under våren 2013. Syftet var att undersöka huruvida något av de energiberäknings-program som används på företaget kan anses vara lämpligt vid energikartläggningar av befintliga fastigheter.Inledningsvis utfördes en energikartläggning av fastigheten Odin 12 i Umeå, som i huvudsak utgörs av gallerian MVG. Med resultaten från denna energikartläggning som grund beräknades därefter fastighetens energianvändning i två olika program ? VIP-Energy och IDA Indoor Climate and Energy.Resultaten från den inledande kartläggningen visar att fastigheten har ett lågt behov av fjärrvärme, vilket förklaras av fastighetens höga elförbrukning. Den stora användningen av el genererar stora mängder internvärme som, förutom att sänka fjärrvärmebehovet, även medför att fastigheten under hela året har ett kylbehov.Utvärderingen av de två beräkningsprogrammen visar att VIP-Energy är ett lämpligt program att använda vid energikartläggningar.

Framtidens driftcentral : En analys av den framtida driften av ett svenskt elna?t

Active work to increase the efficiency of energy use is taking place in Sweden and throughout all of Europe. Electricity is an important part in our society?s energy system which means that the electrical grid operators and associated therewith has a central role in this work. Monitoring and controlling the electrical grids are managed from the distribution system operator?s DC, dispatch center.The aim of this report is to examine how the operations in a typical DC on the Swedish electricity distribution network will look like in five to ten years.

Elever som inte når målen i de samhällsorienterande ämnena : Orsaker och insatser i grundskolans tidigare åldrar

The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.

Värmeförluster vid utvändigt placerade ventilationssystem

To be able to handle tomorrows need for limited energy consumption we need to reduce our use of energy. The building sector stands for around 40 % of all energy consumption in the society. The government has put up a goal to reduce the energy consumption in our buildings with 20 % by year 2020 and 50 % by year 2050 compared with year 1995. To be able to do reach that goal we need a more energy efficient building stock.The main part of the energy used in our buildings is used for space heating. By installing ventilation systems with heat recovery on the exhaust air it is possible to use the heat-energy in the exhaust air to warm up the incoming air.

Accelerometertillbehör till mobiltelefon : - Utveckling av Blåtands ansluten accelerometermodul till smartphone

This master thesis has been carried out as a prototype development project. The project hasbeen performed in cooperation with ÅF Combra AB. The purpose with the master thesis is toconstruct a Bluetooth interface between an accelerometer and a smartphone and constructinga physical prototype containing an accelerometer. This is done to test a new user interface tomobile phones. The master thesis has also included a research about the possibility toimplement distance measuring with Bluetooth.

Jämförelse av solhybrider

Research in solar energy is taking big steps in both solar heating and solar electricity. It´s not only the technologies alone, but also the combination of both solar electricity and solar heating which is what is called a solar hybrid. The idea of a solar hybrid is that a solar cells efficiency decrease with increased temperature and can with help from a solar collector be cooled and the heat can be utilized. This thesis report compares heat production and electricity production with respect of, in first hand, a solar hybrids geometry in the cooler. The theory chapter describes solar heating and how different solar cell technologies work and their environmental impact at the production and how compatible these technologies are for the solar hybrid.

GIS-program för ruttplanering. En studie av nyttjandet av GIS-program för ruttplanering inom tekniska förvaltningar bland kommunder i västra Sverige

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Effektiv fastighetsförvaltning : En beskrivande jämförelse av goda exempel i praktiken och tillämpliga teorier

 Bachelor thesis within Business AdministrationTitle: Effective estate managementAuthor: Joacim StåhlPatrik StyrbjörnTutor: Gunnar WramsbyDate: 2008-06-05Subject terms: Estate management, efficiency, key figure, good examples, manager, real estate Abstract:Background: Concerning the global economy and the picture given in real estate business that efficiency and profitability are needed to survive is it intresting to study and search for good example to reach an effective and profitable estate management.Purpose: The purpose of the thesis is to describe the work of real estate concern to reach efficiency and profitability from the owner/manager perspective.Method: Through qualitative interviews with eight respondents in four different real estate concerns describe good examples on effective estate management and with this fulfil the purpose of this essay. Two interviews per company were made, one at the company and one over phone to reach better security concerning the answers.Theory: The theory is divided in to four mainparts were the first two explains estate management and financial control. Thereafter comes an impression concerning efficiency and how efficiency is secured in estate mangement from a theoratical perspective.Empiri: This part of the essay is about the interviews made and through them show how real estate concern works with efficiency by focusing on good examples in which the companys find themself efficient.Analysis: Comparing the theories and the empirical research to analys and try to describe efficient estate management.Conclusions: Efficient estate management is about controlling the costs and especially about the opreating costs. Important to reach operative efficiency is therefore to continuosly follow up the costs and to do readings every month. To compose and continuosly work with budget and action plans for each estate is important in order to reach efficiency in the management of estates.

Potential för energiklippdrivare i Skåne : markägarintresse, råvarutillgång & ekonomi

As the Swedish governments long term goals include a reduction of fossil fuel dependency, increasing pressure is placed upon energy companies to create and develop new solutions for renewable energy. The following case study was done in collaboration with the company Sydved Energileveranser AB and one of their contractors, Enarssons Skogsentreprenad AB. The objective of the study is to examine the bioenergy situation in region of Skåne and evaluate the potential solutions in the region for a forest-fuel assortment, based on a bioenergy-cutting-system. As a part of this study I have compared ordinary manual cuttings done with a chain saw and cuttings made using the new ?bio- energy cutting system?. The cuttings made under both systems were tested in areas near agricultural fields or pasture land in order to maintain an open landscape.

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