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2090 Uppsatser om Green energy - Sida 32 av 140
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..
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.
Alternativa produktionsmetoder vid anläggningsarbeten Kringgjutning av el- och telekabelkanalisation
I dagens samhälle blir det allt mer intressant att spara energi, dels med tanke på miljön och dels föratt minska på utgifterna. Denna energi ska sparas på ett sådant sätt att effekten för användarna blirså liten som möjligt.I denna rapport beskrivs hur ett reglersystem kan byggas för att minska energiförbrukningen hosväxthus genom att reglera belysningen på ett effektivt sätt. Systemet är helt automatiskt vilket göratt användarna inte behöver tänka på styrningen av lamporna alls när väl systemet är uppsatt ochkonfigurerat.För att styra lamporna på ett bra sätt mäts det inkommande ljuset med en PAR-sensor. Lampornatänds och släcks därefter beroende på ljusmängden och även på hur varmt, eller kallt, det är iväxthusen.Styrningen av belysningen sker med en mikrokontroller från Microchip, en PIC18F4620 som ärprogrammerad i C18. Kringkomponenter som portexpasioner, klocka och reläer användes också föratt bygga ett bra reglersystem.Resultatet är att det är möjligt att bygga ett reglersystem med begränsad budget som styr lampornapå ett effektivt sätt.
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.
Sapa Heat Transfers koldioxidspår : En kartläggning av verksamhetens koldioxidutsläpp
Sapa Heat Transfer is a company that produces aluminum heat-exchanger strips for the automotive industry. Sapa Heat Transfer wish to chart their emissions of carbon dioxide in order to meet future demands on carbon dioxide reporting. They also would like to examine the meaning of the term ?green electricity? which is marketed as carbon dioxide free, and the sort of electricity that they purchase. This report includes both direct (liquefied petroleum gas and diesel) and indirect (water, process-water, long distance heating, waste) emissions from their company.
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.
Kompostering i kommunal regi: en fallstudie i Arvika Parkf?rvaltning
Arvika Fastighets AB is a municipal subsidiary tasked with managing all green areas in the
municipality, with a strong focus on the City Park and plant beds in the city centre. These areas
generate large amounts of green waste, which is currently transported to the municipality's
composting area at Lycke. Currently, the material is piled up and turned once a year without using
the resulting soil for flowerbeds, lawns, and shrub/tree plantings. The purpose of the study is to
determine if Arvika can compost the green waste in a more efficient manner and produce weed-free
soil ready to be mixed into various substrates for different purposes. Interviews with the Swedish
Church and several municipalities in Sweden have been conducted to learn from their experiences
and knowledge of how they make their composting work.
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.
Spelar politiken någon roll? : En jämförelse mellan Kalmar kommun och Karlskrona kommun
Currently, the whole globe is faced with serious problems which negatively affect people around the world: increased pollution, excessive waste, and weather pattern changes. ?Left? and ?right? wing political parties alike have embraced ?green? politics and for many of these parties, environmental issues have become a top priority that is very much reflected in their manifestos. This study examines the environmental goals of two of Sweden?s largest political parties and how these ambitions are reflected at a local level.