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1692 Uppsatser om Excess energy - Sida 57 av 113

Utbyte av massaved och biobränsle i några typbestånd av Contorta :

The aim of this study is to describe a number of type stands of lodge pole pine in Norrbotten with respect on stem volume and total biomass. Further questions to answer is if there is stand characteristics that make the stands more suitable for pulpwood in early thinning, or if it is better to apply whole tree harvest. The study shall also give an indication if bio energy can be an economical interesting alternative for Sveaskog. Sampled trees represented the variation in the different stands. Five trees were selected from each stand to represent that stand. Stem volume and biomass (kg dry weight (DW) per hectare) for each fraction was calculated.

Marknadsundersökning inom datacenterbranschen : Undersökning av tekniska inköp, med fokuspå kyllösningar

The purpose of this thesis is to examine how investments are justified in the Swedish data center industry, with a focus on cooling equipment. This is achieved through semi-structured interviews with 20 different interviewees. These interviewees represent different facets of the industry and facilitate an understanding of which factors, such as: investment costs, operating costs, reliability, environmental impact and the influence of external and internal actors, come into play and to which degree they impact the investment decision-making process. The results show that primarily low operating cost in the form of low energy consumption is the driving factor when it comes to the procurement of new equipment. A lower environmental impact is a positive side-effect of lower energy consumption.

Vindkraftsetablering i skog

This thesis assignment at C-level is focused on calculation models and prediction methodswhish can be used in the stage we call ?prospecting? of possible windmill locations. Thelocation is southeast of Halmstad at the Farm ?Stjernarpsgods?. The rapport has two mainareas directed towards this task.

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.

Pellets - en framtidsmarknad?

With higher prices for oil and increased focus on fossil fuels impact on the environment the heating sector are searching for alternative fuels. Pellets are a quite new product whose production has risen exponential in recent years. Today there are small-, medium-and large-scale users, where the large-scale consumers are the heating sector. The heating sector is mainly using oil to cover the increased demand during cold periods. The purpose of this study is to analyze the potential of pellets if it would replace thermal power plants oil and coal. The study will also analyze the economic impact a conversion would mean for a heating plant and if the pellet is a reasonable substitute. 2008 statistics from the Swedish district heating association were analyzed and a calculation was performed to determine how many tons of pellets is needed to replace coal and oil.

Ett aktivt beslut att renovera passivt : En ekonomisk jämförelse vid upprustning av miljonprogrammetsflerbostadshus

As a result of increased energy prices more and more energy-efficient homes are coveted. An energy-efficient alternative is passive houses, which is characterized by an extremely well insulated building envelope that recovers the heat without the use of radiators or under floor heating. But a passive house requires a higher investment cost than a conventional building project, since it will require more construction materials, training of construction workers, greater land area, and long construction period. But the lower operating cost expects to pay back the higher cost of investment. We therefore question how profitable a passive house is in relation to houses built according to modern conventional building techniques.The aim of our study is to investigate the viability of passive houses compared to convent­ional houses.

Småskalig biobränsleeldad kraftvärmeproduktion : teknik och investeringsutrymme

To achieve the requirements to decrease emissions of greenhouse gases by 20 % by 2020, Swedenneeds to increase its use of bioenergy. In doing so it seems natural that those who already haveaccess to large amounts of biofuels in the form of by-products such as straw, wood chips anddigestible materials take advantage of these assets locally. By combining production of heat withpower production at the farm it may be possible to not only reduce the direct use of fossil fuel forheating but also reduce energy costs.The purpose was to simulate different cases of using a small scale biofueled combined heat andpower plant for farm-based systems. A MatLab-model was developed and used to draw conclusionsabout the costs for production of heat and electricity with different conversion technologies.The model uses climate data to simulate the variations in heat energy demand on a day-to-day basis.The given heat demand is the base of the simulation and from this the possible electric output iscalculated. This study has focused on the impact of the following properties: electric-, heat- andtotal efficiency, fuel, fuel price and specific fuel requirements.

Flygteknik : Konceptstudie av ett obemannat flygplan

Unmanned aerial vehicles (UAV?s) are nowadays greatly appreciated. The advantage over manned airplanes are great since UAV?s can be much smaller and therefore lighter. The goal of this project is to evaluate the performance of an environmentally friendly UAV using only lithium-ion batteries.

Simulering av vindkraftverk och närliggande elnät vid Risholmen i Göteborg i SimPowerSystems

With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.

Evaluation of RCM implementation process in Vattenfall
Service and Vattenfall, Hydropower organizations: a study and
analysis of its current status

Vattenfall AB is a large producer of electric energy where approximately half of the energy comes from hydropower. Vattenfall Hydropower has got almost a 100-year old history and the company has developed a lot since 1909. After that the number of power plants increased and the competition got more intense, there were higher demands on the reliability. One way to secure the reliability with a good satisfaction at the power plants is to implement a maintenance method named Reliability-Centred Maintenance. RCM is a result of the introduction of the complex aeroplane Boeing 747 in the 1960?s.

Vallfoder till slaktgrisar : effekter på tillväxt och social beteende vid utfodring

The aims with the project were to investigate how forage consumption affect production and pigs behaviour around the feeding. This degree project was designed to follow 48 growing/finishing Hampshire*Yorkshire pigs, from 30-110 kg live weight, fed diets with or without 20 % forage inclusion. The pigs were divided in three groups due to dietary treatment. In the first group the pigs were fed 20 % of the energy in the feed ration by long grass/clover silage (LE) and the remaining 80 % by a cereal concentrate. Group two was fed chopped grass/clover silage mixed with cereal concentrate (HE) in the same amounts as LE.

Åtgärder för att energieffektivisera befintliga industrilokaler vid renovering av klimatskal

För att minska energiförbrukningen i Sverige krävs att befintliga byggnaderen ergieffektiviseras. Det finns även befintliga lokaler i landet som är i behov av en sänkt energiförbrukning. Det sker ständigt initiativ kring arbete med energieffektivisering av framför allt bostadshus. När energiförbrukning ska sänkas i industrilokaler läggs fokus på att minska energiåtgången i de invändigaprocesserna men inte i det omgivande klimatskalet där transmissionen utgör en stor del av energiläckaget. Syftet med arbetet är att öka kunskapen om energieffektiva åtgärder vid renovering av klimatskal hos industrilokaler.

Bioenergy from the forest ? a source of conflict between forestry and nature conservation? : an analysis of key actor?s positions in Sweden

Bioenergy from the forest has been heavily debated in Sweden for several decades due to the interest of society to decrease dependence upon fossil fuels and limit the effects of climate change. The actual use of bioenergy from the forest has shifted over the years but increased during the last decades. Private actors within forest and nature conservation sectors play an important role for the development of bioenergy from the forest as well as for the debate and the implementation of political goals. Forestry in Sweden is characterised by ?freedom under responsibility? for private actors and the perspective of governance is valuable for studying actors and discourses.

Förebyggande av hypotermi under narkos på hund och katt: vad görs på svenska djursjukhus idag, och vilka evidens finns för olika behandlingsmetoder?

Hypothermia during anaesthesia is a well-known phenomenon that may cause several side-effects such as greater risk of postoperative wound infection and increased risk of heart complications. The most efficient way to avoid this is to prevent hypothermia from occurring. The aim of this paper was to compile the research on the most efficient way to prevent hypothermia during anaesthesia for cats and dogs, and to compare these results to how Swedish animal hospitals prevent hypothermia today. To investigate this, a survey was sent out to several animal hospitals around Sweden to see what methods they used to prevent hypothermia in their clinics. It is difficult if not impossible to prevent the body temperature from falling slightly when anaesthesia is induced because of the drug interactions in the body that follow from the drugs given. A 1-1,5°C decrease in body temperature is to be expected and is difficult to avoid.

Ekonomiska styrmedel på kraftvärmeområdet. - Inverkan på ett framtida kraftvärmeverk.

Ekonomiska styrmedel som skatter, certifikat och handel med utsläppsrätter påverkar lönsamheten i ett kraftvärmeverk. Det är viktigt för investerare att ha god insyn i tendenser och förändringar på styrmedelsområdet, eftersom det kommer att påverka investeringsobjektets framtida lönsamhet.I arbetets andra del undersöks hur styrmedelsförändringar påverkar lönsamheten för större investeringar i kraftvärmeverk med naturgas, avfall och biobränslen..

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