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1871 Uppsatser om Energy losses - Sida 29 av 125

Vindkraftens framtida scenarier

In several countries that have been early in the development of wind farms, there is today a second hand market for the used wind turbines. The European Union (EU) has established a waste hierarchy in order to minimize throwaway mentality. The second hand market is a part of this as the steps are to minimize, reuse, recycle, extract energy and landfill.In order to promote the development of renewable energy, there are energy certificates for the producers that provide it, wind power being one type of renewable energy. After 15 years the energy certificates for a specific wind turbine are no longer paid, and after that there are several different scenarios for the wind turbine. The scenarios investigated in this bachelor?s thesis are export of the wind turbine to countries that are not as far along as Sweden in their development towards renewable energy, selling in Sweden to individuals, and recycling of the wind turbine, as it mostly consists of metals and therefore is recyclable.

Elektrisk skorstenständare

Between 1965 and 1974, the Swedish Parliament decided to build one million dwellings, called Million Program. The million program buildings were erected with new, untried design solutions, in a short range of time, and at low cost. The residential buildings from that time are now greatly in need of renovation. The municipal housing company, Gavlega?rdarna, renovates and improves the energy efficiency at some of it?s apartment buildings in the district Sa?tra, Ga?vle.

Frigörelse av fosfor från färskt, fryst och torkat växtmaterial : ett laboratorieförsök för att öka förståelsen för fosfordynamiken inom växtodlingen

Phosphorus is the single most potent contributor to eutrophication of freshwater and has also been shown to contribute to the toxic algae blooms in the Baltic sea. The dynamics and paths of losses of phosphorus from arable lands are not fully understood. It is known that phosphorus can be lost directly from plant material to water. In studies where plant material has been subjected to several freeze-thaw cycles, large amounts of phosphorus have been lost. Most studies have been conducted under field conditions, with many factors effecting the measured losses of phosphorus, such as weather and type of soil. This study was performed in a controlled environment without the presence of soil. Instead of soil, small glass beads were mixed with the plant materials in vessels, to make possible homogeneous leaching with water through the mixture of glass beads and plant materials. In this study, clover, ryegrass and dry straw were cut to pieces, approximately 2 cm long.

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.

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.

Ingen täckning av plansilor samt alternativa täckningsmaterial

Silage is today a common feed for different animals. A general way of storing silage is in bunker silos covered with polyethylene film. The covering and uncovering is labour intensive and it is often difficult to get the silo properly sealed. Because of these reasons many American farmers leave their silos uncovered and accept the losses accompanied. One purpose of this study was therefore to examine if it sometimes can be justified to leave bunker silos uncovered.

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.

Optimerad styrning av kondensatorbatterier - Ny möjlighet att minska förluster med elektronisk brytteknik

Transmission of reactive power is well known to cause active power losses. Thus, newcomponents who can help minimizing these expensive reactive power flows are ofgreat interest to the power distribution companies. ABB Corporate Research hasdeveloped the first electronic power breaker. One possible application for thisbreaker is transient-free switching of capacitor banks. This could prove a usefuldistribution voltage complement to the switch-sync technique, mainly applied to transmissionvoltage level.

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.

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