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1843 Uppsatser om Energy combine - Sida 26 av 123

Från alger till biodiesel - Den italienska drömmen?

This project aims to investigate whether algae can be used for biodiesel production in Italy. Algaes are a good option since they are fast growing and do not occupy arable land. The aspects that have been considered are growing, harvesting, which algae strain that is most suitable, extraction of oil, the production of biodiesel and where in Italy this could be possible due to climate. Cost? and energy calculations have been made to investigate if biodiesel produced from algae would be profitable. During the production of biodiesel there are several residues obtained. When the oil has been extracted from the algae, biogas is produced from the residual biomass by anaerobic digestion and then the electricity that can be produced is supplied to the production of biodiesel.

Effekten av olika andelar grovfoder och kraftfoder i foderstaten på mjölkproduktion, välfärd och hälsa hos mjölkkor

Dairy cows transform grass to milk with help from ruminal microorganisms that can digest indigestible fiber in their feed. The digestive system of the cow is adapted to a diet consisting of forage and disorders like acidosis, laminitis and abomasal displacement can occur if the feed contains too much starch. To achieve the highest production possible the cow has to be given a high amount of concentrate or grain as the difference in milk yield is significant, approximately 1000 kg energy corrected milk per cow and year between conventional and organic cows that are fed a lower versus a higher share of forage. If the cow shall be able to eat the same amount of energy from forage as from grain or concentrate the eating- and rumination time gets longer and she might not be able to eat enough, which will result in a lower milk yield and will make it harder for the cow to recover from the negative energy balance that originate from the beginning of the lactation. Fat and in a sense protein content differs also depending on if the cow is given a high or low share of forage..

Gröna lösningar - en fallstudie av aktuell teknik för energieffektivitet för Skanska Sverige ab 

ur society is today in a phase of development in environmental and sustainable thinking. Alarming reports show changes in climate caused by our load and exhaust of resources. The energy usage contributes to a big part of it, by its emission of carbon dioxide. The built environment uses around 40 % of the total energy consumption in Sweden and requests to strongly reduce it are presented from both EU and national level.This thesis brings up the subject of green building with a focus on how we can create more energy efficient buildings in projects of new construction. Since the construction industry today often fails to pass on the knowledge between different projects, as a return of experiences, the construction company Skanska suggested the topic for this thesis.

Energieffektivisering av Åhlénshuset i Umeå : Utredning av åtgärder för ventilation, värme och kyla

Sweden is a country that has made some progress in developing energy efficient solutions. The problem in Sweden is that many houses and apartment buildings are old and have inefficient ventilation- and heating systems. This energy is lost when systems are inefficient, which then results in huge economic costs. Luckily, more and more people are becoming aware of this, which means that Sweden is on track to become even better within energy efficiency.Energy use for the housing- and service sector amounts to 166 TWh of total use at 616 TWh. Without distribution and conversion losses, these figures show that the housing- and service sector accounts for almost 40 % of the country's total energy consumption.

Vakuumisolering ? Ekonomiskt försvarbart för småhus?

The number of people in the world and the urbanization increases. This leads to a bigger need of space for the built environment, space that soon doesn?t exist. A large portion of humanity?s energy disposal is used for heating of buildings.

Effekten av frukostens glykemiska index på energiintag hos barn och ungdomar

Sahlgrenska Academyat University of GothenburgDepartment of Internal Medicine and Clinical NutritionTitle: The effect of the glycemic index of breakfasts in energy intake inchildren and adolescentsAuthor: Charlotte Olofsson, Cornelia Johansson and Maria NordbeckSupervisor: Fredrik BertzExaminer: Ingrid LarssonProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 16, 2013Background: The glycemic index (GI) and it´s effect on energy intake is a debated subject.Research has been done whether food with lower GI decreases hunger and lowers energyintake, which could be an effective tool to prevent overweight in children and adolescents.Breakfast eating is successful for maintaining a healthy weight and it´s therefore interesting tosee if the quality of the carbohydrates matters.Objective: To evaluate the scientific evidence regarding the effect of GI of breakfasts inchildren?s and adolescents energy intake.Search strategy: To find relevant articles, a systematic literature search was made in thedatabases PubMed, Scopus and Cochrane. Search terms that were used were: breakfast,breakfast quality, children, glycemic index, energy intake, obesity.Selection criteria: Randomized controlled trials and cohort trials, breakfast eatingindividuals, children and adolescents under 18 years old, reported glycemic index. Outcomemeasurements: Energy intake.Data collection and analysis: Six original articles met the inclusion criteria and werereviewed by the SBU audit template for randomized and controlled studies. There after onearticle was excluded because of very low quality of the study.

Tätskikt i klimatskal : En studie av byggentreprenörers arbetssätt

As energy prices skyrocket and the environmental issues become more frequently debated, interest in energy-efficient buildings has increased sharply in the past decade. Because of this, the interest to achieve high air tightness in building envelopes have once again awakened, due to a good air tightness contributes to lower energy consumption in several ways and to a healthier indoor environment.As the regulations for energy consumption and controls of achieved air tightness has tightened considerably in recent years, the work regarding sheets for air tightness changed significantly for construction contractors. This thesis includes a study that aims to detect what kind of manuals, recommendations or instructions contractors working according, and how a number of randomly selected construction companies in Halland, Sweden, are dealing with the matter of high air tightness of the building envelopes. The study also includes a knowledge inventory of supervisors, site managers and skilled workers, and what their opinions and attitudes are like towards work regarding the sheets of air tightness. The results have been compared with a similar survey dated to 2004, conducted by the SP Technical Research Institute of Sweden in collaboration with Chalmers University of Technology.

Studie av energianvändningen på Spira förskola: En jämförande studie av faktiskt och simulerad energianvändning samt en parameterstudie av ingående data vid simuleringar av energianvändning

I detta arbete har den faktiska och simulerade energianvändningen på Spira förskola i Luleå undersökts. Den faktiska specifika normalårskorrigerade energianvändningen fastställdes till 121,4 kWh/kvm år. Vid projektering av förskolan uppskattades den specifika energianvändningen med hjälp av simuleringsprogrammet VIP-Energy till 78,5 kWh/m2 år. Därmed översteg den verkliga användningen den simulerade med 54,6 %.En parameterstudie av indata till simuleringsprogramet har också genomförts med avsikt att fastställa den totala förändringen i energianvändning då indata ändras. Följande parametrar har studerats;?Drifttid hos ventilationssystemet?Horisontvinkel?Inomhustemperatur?Klimatzonen?Kvot mellan till- och frånluft?Luftomsättning för ventilationssystemet?Solreflektion från omgivande mark?Temperaturverkningsgrad?Vindhastighet?Vridning av byggnadenNyckeltal som kan användas för att snabbt uppskatta påverkan på den totala energianvändningen har också sammanställts för majoriteten av de studerade parametrarna.

Möjligheter och hinder för aggregerad förbrukningsflexibilitet som en produkt på reglerkraftmarknaden

Electricity production from renewable energy resources such as wind energy and photovoltaics is variable. Integration of these intermittent resources into the electricity system leads to new challenges in how to manage imbalance between supply and demand on the grid.One way to meet these challenges is to develop so-called smart grid solutions. One idea, called demand response, is to adjust the amount or timing of energy consumption, e.g. by control of household appliances, to provide flexibility that could be used to balance the grid. In aggregate, when applied to many units across the system, large volumes of energy could be made available when needed and this grid flexibility can be used as a product on the electricity regulation market.Despite the potential benefits, the number of demand response bids is currently low.

Beräkning av värmeförluster och energieffektivisering av elbussar

The ?civilized? world is in need of fossil fuel in order to function. Hybricon AB is a company in Umeå that is developing a technology that hopefully can reduce parts of this need. They are currently testing their two electrical busses (with Hybrid backup) in city traffic on the roads of Umeå in cooperation with the county of Umeå.                               The busses are originally diesel-busses, but the diesel motor has been replaced with two electrical hub-motors with a power of 145 kW each that are powered by batteries.The batteries are charged at the end station after each route. In case the batteries should run low on capacity during driving, they can be recharged by the so called genset.

Dubbla uppdrag : En kvalitativ studie av två profilerade och integrerade folk- och skolbibliotek

The aim of this master?s thesis is to examine libraries which combine the functions of school- and public library and to evaluate the staff?s experience and attitude towards a library profile with the emphasis on children and youth. The purpose of the study is also to examine how the libraries work with several tasks and functions within different target groups with different needs.With new institutionalism and Scandinavian institutional theory the thesis examine the library as an organization and what influences the construction. With a model that describes how the library constitutes four different rooms in the society I investigate the different functions.The methodology is qualitative with interviews of five persons of the staff, four librarians and one library assistant. The study examines how the staff that works at two libraries under similar conditions experiences their tasks.

Energianalys mellan programmen IES (Integrated Environmental Solutions) och Enorm

An increase interest of new methods and tools has begun to grow in the real estate business, this new trend causes an increase in new programs that aim to simplify processes of energy-efficiency and environmental issues.After consulting with Björn Alsmark from Bjerking AB, an architect and engineering company, we made a decision that the Degree Project is going to examine the program IES (Integrated Environmental Solutions) with some integrations from Revit Architecture application.To be able to examine IES, we got access to a completed project from Bjerking. The project is a nursery school in Uppsala. An application has been handed in from Bjerking to make this project to a Green Building-certificated project. According to Bjerking own calculations (with the energy-calculation program Enorm), the consumption of energy of the nursery school is 48 percent lesser than required by BBR.An evaluation of IES and Enorm has been made with an aim to compare these two programs and find out if IES is an appropriate program to replace Enorm. Does Enorm or IES come up to BBR´s recommendations?The Degree Project cover 15 ECT, that required several adjusting and delimitations, and the study sketch ended with a literature study.After finishing the study sketch the modeling of the nursery school began.

Utvärdering av inomhuslokalisering med Bluetooth Low Energy

Wireless communication is becoming more common, a relatively new technology within the area is Bluetooth Low Energy. It?s been developed to be energy efficient and in regard to compatibility. Alongside the growth of wireless technology, scientists and companies are looking for new areas of use. One of these is localization, which means to determine the position of a moving device with the use of stationary devices, an example of this would be GPS.This report means to evaluate indoor localization using Bluetooth Low Energy and was made for Combitech AB in Jönköping.

Småskalig säsongslagring av solenergi för uppvärmning av bostäder : Simulering av lagerutformning och konsekvensen av adderade uppvärmningsbehov motsvarande en pool och ett atrium

The sun is a huge energy source with great potential of providing energy to the heating of homes and other buildings in an environmentally sustainable manner. In order to provide buildings with energy from the sun it is necessary to transfer the energy supply over time to when the demand arises. By storing the heat in a seasonal storage, solar energy from the summer can be used in the winter when the demand for heating is greatest.Today's existing plants are mainly in Europe and particularly in Germany. These facilities are designed to supply heat demands greater than 400 MWh and covers about 40-50 % of this need which consists of energy for space heating and domestic hot water. How much of the heat demand that is covered, the solar fraction, is partly due to losses from the storage which in turn is connected to the surface area of the storage.

Matematisk generering och realtidsrendering av vegetation i Gizmo3D

To render outdoor scenes with lots of vegetation in real time is a big challenge. This problem has important applications in the areas of visualization and simulation. Some progress has been made the last years, but a previously unsolved difficulty has been to combine high rendering quality with abundant variation in scenes. I present a method to mathematically generate and render vegetation in real time, with implementation in the scene graph Gizmo3D. The most important quality of the method is its ability to render scenes with many unique specimens with very low aliasing.

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