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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Utveckling av analysverktyg för verksamheters CO2-utsläpp och energianvändning

Berggren, Hanna, Norrman Andersson, Hanna January 2008 (has links)
<p>With increasing energy prices and increased focus on the environment we saw the need for companies to get control over their energy use and their emission of carbon dioxid. An analysis tool that integrates both these areas is, with our knowledge, not available on the market today. Therefore, our project became to develop such a tool.</p><p>By doing this degree project we would like to clarify that energy consumption and environmental impact are integrated. The less energy consumed by today’s society the smaller the environmental impact will be. Seen from an economical point of view the benefits from a reduced energy use are significant due to the fact that costs will diminish, for companies as well as people in general. Even the choice of energy source has an effect on the environmental impact.</p><p>The objective has been to provide a tool which companies can use to conduct their own analyse on their energy consumption and carbon dioxide emission, and also point out where in their business they can find such “hot-spots”.</p><p>In the provided Microsoft Excel based analyze tool there is a total of eight different sections out of which six concerns different parts of a company. Five of these six sections will be filled out by the user and the sixth gives a compilation of the company’s energy consumption and carbon dioxide emission. These sections are: Start, Introduction, Electricity, Heating, Cargo transports, Personal transports, Compilation and References. The sections are organized to make it more user friendly and to show the most important parts of a company, concerning both energy consumptions and carbon dioxide emission. </p><p>When we considered the tool to be finished, we had it sent out to a number of companies that tested it on their businesses and returned their opinions and suggestions on various changes.</p><p>In the beginning of the project our objective was that at the end we would have a complete tool ready for companies to use on their activities. This however, turned out to be too much of a challenge, which we realised after just a few weeks. The produced tool instead became a prototype for further development. All in all, the work has given us a valuable insight in the magnitude of work and time required for developing this kind of analysis tool.</p>
2

Utveckling av analysverktyg för verksamheters CO2-utsläpp och energianvändning

Berggren, Hanna, Norrman Andersson, Hanna January 2008 (has links)
With increasing energy prices and increased focus on the environment we saw the need for companies to get control over their energy use and their emission of carbon dioxid. An analysis tool that integrates both these areas is, with our knowledge, not available on the market today. Therefore, our project became to develop such a tool. By doing this degree project we would like to clarify that energy consumption and environmental impact are integrated. The less energy consumed by today’s society the smaller the environmental impact will be. Seen from an economical point of view the benefits from a reduced energy use are significant due to the fact that costs will diminish, for companies as well as people in general. Even the choice of energy source has an effect on the environmental impact. The objective has been to provide a tool which companies can use to conduct their own analyse on their energy consumption and carbon dioxide emission, and also point out where in their business they can find such “hot-spots”. In the provided Microsoft Excel based analyze tool there is a total of eight different sections out of which six concerns different parts of a company. Five of these six sections will be filled out by the user and the sixth gives a compilation of the company’s energy consumption and carbon dioxide emission. These sections are: Start, Introduction, Electricity, Heating, Cargo transports, Personal transports, Compilation and References. The sections are organized to make it more user friendly and to show the most important parts of a company, concerning both energy consumptions and carbon dioxide emission. When we considered the tool to be finished, we had it sent out to a number of companies that tested it on their businesses and returned their opinions and suggestions on various changes. In the beginning of the project our objective was that at the end we would have a complete tool ready for companies to use on their activities. This however, turned out to be too much of a challenge, which we realised after just a few weeks. The produced tool instead became a prototype for further development. All in all, the work has given us a valuable insight in the magnitude of work and time required for developing this kind of analysis tool.
3

Luftomsättningsmätning med avklingningsmetoden: fältmätningar med CO2 som spårgas. : Studie i en 3-plansvilla med självdragsventilation.

Chilo, Johannes, Heinola, Niina January 2016 (has links)
Denna uppsats redovisar ett resultat från en studie gjord på uppdrag av villaägare till ett hus från 1972 med självdragsventilation. Utifrån dialog med villaägarna har det framkommit att de misstänker att ventilationen inte är tillräcklig. Om ventilationen inte fungerar som avsett kan det uppstå hälsoproblem för människor, genom ökade halter av fukt och luftföroreningar. Boverket ställer krav på en lägsta luftomsättning på 0,5 oms/h uteluftsflöde, 0,35 l/s per m2 vid ny- och ombyggnation. Syftet med studien är att ta fram luftomsättning och CO2-halt med hjälp av avklingningsmetoden och CO2 som spårgas. Syftet är också att sammanställa vilka lagkrav, riktlinjer och rekommendationer som gäller för luftomsättning och luftflöde inomhus. Studien är begränsad till avklingningsmätningar i villans boarea. Avklingningsmetoden utfördes i fyra sovrum, två WC och ett badrum; samtliga försedda med en frånluftsventil. WC, badrummen och ett av sovrummen uppnådde det rekommenderade kravet på luftomsättning. Sovrummet med lägst omsättning uppnådde inte rekommendationen troligen på grund av horisontell och längre luftkanal. Sovrum, med frånluftskanal intill den varma kanalen från kaminen fick snabbare luftomsättning när det eldades i kaminen. Det andra sovrummet, med frånluftkanalen i skorstenen, men isolerad från den varma kanalen från kaminen, fick ingen märkbar ökning av luftomsättning. Datainsamling av temperatur, relativ fukthalt och CO2-halt mättes i fyra sovrum under två nätter, en natt med stängd dörr och en natt med helt öppen dörr. Luftkvalitén blev bättre med öppen än med stängd dörr nattetid. CO2-halten uppnådde inte några skadliga halter på tack vare sovrummens stora volymer. Avklingningsmetoden på totala boarean fick avbrytas på grund av att homogen omblandning av CO2 i luften inte kunde uppnås. Studien visar att självdragssystem är känsliga för väderförhållanden. Husets luftomsättning uppnådde inte rekommendationerna. I studieobjektet är frånluftsventiler är placerade i sovrum och därmed felaktigt placerade enligt Boverket och Folkhälsomyndigheten. De rekommenderar att tilluftsventiler tillför frisk luft i rum där människor vistas mest, exempelvis sovrum och vardagsrum. Rekommendationer till villaägarna är att inte förhindra ventilationssystemets flöde vid ombyggnationer. Exempelvis vid fönsterbyte bör fönsterventiler med tilluft installeras för att öka tilluftsflödet. Ventilationssystem bör ses över av en fackman om en konvertering till ett mekaniskt ventilationssystem är möjlig för att säkerställa en god och hälsosam inomhusmiljö. För att öka utomhusluftstillförseln bör vädring utföras regelbundet. Vi rekommenderar framtida studier att utföra mätningar under längre perioder och under olika årstider. / This paper presents the result of a study commissioned by the owners of a house of 1972 with natural ventilation. Discussion with the owners has revealed that they suspect that the ventilation is not adequate. If the ventilation is not working properly it can cause health problems for people through increased levels of humidity and air pollution. Boverket requires that the minimum air change rate should be 0.5 per hour or an outdoor air flow of 0.35 l/s per m2 in new- and reconstruction of buildings. The purpose of the study is to calculate air circulation by using tracer gas dilution method with CO2 as tracer gas accordance with ISO 12569: 2012. The aim is also to compile the legal requirements, guidelines and recommendations that apply to the air exchange and air flow indoors. The study is limited to the living space of the house. Tracer gas method is performed in four bedrooms, two WC and a bathroom; all with exhaust ventilation. WC, bathroom and one of the bedroom achieved the recommended requirement for air change rate. The bedroom with the lowest air change rate did not reach the recommendation probably due to the horizontal and longer air channel. Bedroom, with the exhaust ventilation canal beside the warm canal from the fire place, had faster air change when the fireplace is heated. The bedroom, with the exhaust ventilation canal isolated from the warm canal from the fire place, remained unaffected. Data collection of temperature, relative humidity and CO2 was measured in four bedrooms over two nights. One night with the door closed and one night with a open door. The air quality was better with the door open than with the door closed. CO2concentration did not reach harmful levels due to the large room volume. Tracer gas method in total living area had to be interrupted because homogeneous mixture of CO2 could not be achieved. The study shows that natural ventilation systems are sensitive to weather conditions. The air change rate in the building did not reach the recommendations. The positions of the ventilations are improperly according to the requirements of the Boverket and Folkhälsomyndigheten. They recommend that the supply ventilation should provide fresh air to bedroom and livingrooms, but in this study the building have exhaust ventilation in the bedrooms instead. The recommendation to the house owners is to not prevent the ventilations flow in while making reconstruction. For example, when replacing to new windows should supply ventilation be installed to increase the air supply. Ventilation systems should be reviewed by a ventilation expert if a conversion to a mechanical ventilation system is possible to ensure a good and healthy indoor environment. To enhance the outdoor air supply should the windows and doors open regularly. We recommend future studies to take measurements over longer periods and in different seasons
4

Elevers tankar om klimatförändringar

Rantala, Hanna January 2012 (has links)
This work examines the students´ thoughts on climate change with a focus on carbondioxid through photosynthesis and the carbon emissions from cars. The study is based on two subject areas, one with a focus on enhanced greenhouse effect, and the other focusing on photosythesis. The survey was conducted by means of qualitative interviews with students in grades four and six. The results describe that student´s understanding for photosynthesis and the carbondioxids function for photosynthesis doesn´t change significantly from grade four to grade six. I have divided the students inte three levels based on their understandingof the various fields, and their use of adequate concepts. The study gives an understanding of how students perceive the different areas of research. The results show a marginal difference between the students and their explanations in the two grades.
5

Energieffektiva åtgärder för flerbostadshus / Energy efficient measure for apartment buildings

Edlund, Fredrik January 2014 (has links)
Energy is a hot topic in today's society. Both businesses and individuals are trying to reduce their spending costs by saving kWh. There are many various saving measures to reduce energy consumption. Reducing energy consumption leads to a reduced carbon footprint as less fuel is burned in facilities that generate emissions. This report will focus on heat pumps, solar technologies and interventions in the building envelope for a multi-dwelling house.   How much energy can be saved from a measure? What impact does it have on the climate? Is it economically viable to invest in the measure? These issues are of importance both for the investor and future generations. In the report, these questions are answered and applied in a multi-dwelling house in Karlstad built in the 1960's with an energy consumption of 129 kWh/m2 and year. The study is a collaboration with HSB.   The building was recreated in a simulation program, VIP-Energy, for a basic case to start from. Then the measure were simulated both individually and in combination to see how effective they are in the building. These measures may lead to an increased electricity consumption, which was taken into account in the calculations of the climate impact if it led to an increased or decreased amount of CO2 emissions. All these measures are designed to reduce energy consumption, leading to a decrease in energy cost.   The results showed that these measures lead to a saving of energy consumption in all cases. The resulting reduction in energy consumption varies between 5-50% on the various measures individually, but the savings do not differ as much. The reason for this is the technical lifetime of the measures, which means that the total savings do not reflect the reduction in energy savings. Reduced CO2-emissions is much more difficult when the building is connected to a district heating plant that also produces electricity, known as a combined heat and power plant, which makes the reduced heat generation leads to reduced power generation. This means that the electricity has to be generated from another source, for Sweden this means imports of electricity from a coal condensing power plant. Electricity from the power plant is in this case CO2-compensated, which means that the fuel comes from a renewable source. In order to have reduced CO2-emissions, it requires that you have your own production of electricity from CO2-compensated or renewable sources.
6

Swedish district heating systems and a harmonised European energy market : means to reduce global carbon emissions /

Sjödin, Jörgen, January 2003 (has links) (PDF)
Diss. Linköping : Univ., 2003.
7

Possibilities of CO₂ emission reduction : process integration analysis and carbon trading schemes /

Wang, Chuan, January 1900 (has links)
Diss. (sammanfattning) Luleå : Luleå tekniska universitet, 2007. / Härtill 7 uppsatser.
8

Patienters upplevelser av koldioxidkontrast vid en CT-kolon undersökning : Litteraturstudie: Slutversion av Santeri Kriikkula / Patients experiences of carbon dioxide contrast in conjunction with a CT-colon examination

Kriikkula, Santeri, Omar Osman, Muna January 2016 (has links)
No description available.
9

Attityder till att spara el inom VA-sektorn : i verksamhet kopplad till pumphus

Olsson, Marie, Rosengren, Maria January 2004 (has links)
No description available.
10

Attityder till att spara el inom VA-sektorn : i verksamhet kopplad till pumphus

Olsson, Marie, Rosengren, Maria January 2004 (has links)
No description available.

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