Energy is an essential part of the society and for a sustainable future we need to use the energy resources in a sustainable way. The forest is Sweden?s most important resource for renewable energy and a higher production combined with shorter rotation periods (time from planting to clear cutting) can increase the access to energy. The tree genus poplar (Populus spp.) is interesting as energy resource as it has both high production and short rotation period. But browsing ungulates are a major threat to the establishment of poplar plants and therefore the poplar plantations need to be fenced in today. To use fences is expensive and time consuming; this makes it interesting to find more cost-effective solutions where there is no need to fence. The aim with this study was to look at the ungulates? occupation rate and browsing pressure in poplar plantations without fence.

This diploma work has been carried out in collaboration with the building contractor Sh Bygg Fastighetsutveckling AB in Uppsala with the intention to investigate how the height of a building affects various energy aspects such as transmission losses, infiltration, and the specific energy usage. Three different reference objects have been studied. The reference objects have been simulated for four different heights in the calculation program VIP-Energy.The results show that an increase in floor number can lead to both advantages and disadvantages. As the number of floors increases, transmission losses per square meter floor area decreases. However, as the height of the building increases, the reduction rate decreases.

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.

Many of todays studies show that district heating is one of the betteralternatives as heating source because of its low environmental load.The energy source is often leftovers from other processes producing energy or waste, like garbage or chips.Electricity in combination with geothermal heating is another heating system that has increased sharply during the last years, and also this system decreases the discharges that have negative affectson the environment compared to several other heating methods.This report aims to, concentrated towards these two different heating systems, estimate the amounts of discharges they indirect cause and how the environment is affected.We have calculated the mean value for discharges of carbon dioxide, nitrogen oxide, sulphur oxide and dust generated from electrical power used in Sweden.Through interviews and research we have gained data for the same substances that district heating based on combustion of garbage and biofuel generates.We have also in cooperation with a housing company chosen a building we see representative for many of the new single-family houses built in Sweden today.Based on its shape and appearance we theoretically created three alternatives of the same house, each of them with climate screens different from each other.Together with the amounts of discharged environmental affecting substances, these houses were the base for our calculations and studies when investigating the different heating sources environmental effect.The results have thereafter been analyzed and discussed from different angles..

The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.

This project investigated the current market regarding wireless net and the communication between the tools used for diagnostics/maintenance and an embedded system. Based on documentation obtained through interviews a demo system was created based on Bluetooth Low Energy (BLE) communication between an embedded system and an Android device.This report intends to describe the tools and methods used in the design of the demo system and the result of an analysis of the BLE communication.Bluetooth Low Energy is an exciting protocol with wide applicability within the industrial field. This project investigated the communicational possibilities between a Smartphone and a Raspberry Pi and based on the results that emerged the conclusion can be drawn that BLE is a protocol with many beneficial applications within industrial IT..

The purpose of this master thesis is to investigate how nearby forests affect the energy production in wind turbines. To reach the purpose a case study is performed on three wind turbines sited on a field in a north-south line at Andersfält in the municipality of Halmstad, Sweden. Approximately 100 meters south of the southern wind turbine a forest is situated. The case study is divided into three sub studies where the difference in energy production, the affect of the forest and a wind meteorology model, WAsP, is studied. The result show that the forest have a significant influence and that the WAsP-model gives an incorrect result of the energy production in wind turbines sited near a forest..

På uppdrag av Sweco Systems i Umeå har detta examensarbete utförts under våren 2013. Syftet var att undersöka huruvida något av de energiberäknings-program som används på företaget kan anses vara lämpligt vid energikartläggningar av befintliga fastigheter.Inledningsvis utfördes en energikartläggning av fastigheten Odin 12 i Umeå, som i huvudsak utgörs av gallerian MVG. Med resultaten från denna energikartläggning som grund beräknades därefter fastighetens energianvändning i två olika program ? VIP-Energy och IDA Indoor Climate and Energy.Resultaten från den inledande kartläggningen visar att fastigheten har ett lågt behov av fjärrvärme, vilket förklaras av fastighetens höga elförbrukning. Den stora användningen av el genererar stora mängder internvärme som, förutom att sänka fjärrvärmebehovet, även medför att fastigheten under hela året har ett kylbehov.Utvärderingen av de två beräkningsprogrammen visar att VIP-Energy är ett lämpligt program att använda vid energikartläggningar.

An energy study has been performed on two blocks in an area called Gävle Strand. The buildings are owned by a tenant-owner?s association called brf Carolina and were built by the company Skanska 2008. The builder as well as brf Carolina are pussled by the fact that electricity use is higher than expected while heating is less. Skanska is also very interested in finding out how much heat recovery from stale exhaust air through a geo-thermal heat pump is contributing to the general heating requirement and energy balance in four out of the ten buildings located on the properties.To find possible answers to the higher electricity use a literature survey on user behaviour was conducted.

The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.

To be able to handle tomorrows need for limited energy consumption we need to reduce our use of energy. The building sector stands for around 40 % of all energy consumption in the society. The government has put up a goal to reduce the energy consumption in our buildings with 20 % by year 2020 and 50 % by year 2050 compared with year 1995. To be able to do reach that goal we need a more energy efficient building stock.The main part of the energy used in our buildings is used for space heating. By installing ventilation systems with heat recovery on the exhaust air it is possible to use the heat-energy in the exhaust air to warm up the incoming air.

The purpose of this study is the reports of Peak Oil in Swedish newspapers. In otherwords, how do the news portray or describe the concept and what sources are usedwhen writing articles. With this in mind, I have studied eight published articles in threeSwedish newspapers, Dagens Nyheter, Dagens Industri and Svenska Dagbladet. To studythese articles I've used a qualitative content analysis, as a method, or more specific aCritical Discourse Analysis (CDA). This method was chosen due to it's tools to examinethe text itself and to reveal the structures, unconscious meaning and power of words.Further more I have used theories as agenda-setting (including framing and priming),ideology and newsworthiness to complement the study.The result from the content analysis shows two evident ideologies, one with aneconomic perspective and the other with an environment perspective ? with resourcelimitation in mind.

This essay consider ritual death during the ironage, and through a presentation of historical and archaeological sources. Considered ritual death I think we should study both historical and archaeological sources, to get a vider view and a new perspective. To make the essay easier to understand I have split up the early and the late Iron Age in the discussion. In order to study the ritual death I have shown archaeological examples like bogsacrifices in the early ironage, and decapitated victims in the Viking society. The victims have been considered as slaves by some archaeologist.

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Biogas mainly consists of methane and carbon dioxide, where methane is theenergy-rich gas, and is naturally created when organic matter breaks down in absenceof oxygen, also known as anaerobic digestion. A biogas plant re-creates the anaerobicconditions inside a digester where the organic substrate is fed into and digests toproduce biogas. The gas is then used to produce energy by combustion and can beseen as a completely renewable fuel.Today, energy from biogas is used primarily by major stakeholders such asmunicipalities and thus the plants become very large with high investment- andconstruction costs. There are currently few small plants in Sweden, even though thepotential for agriculture and medium-sized to smaller farms to become self-sufficientin terms of electricity and heat is great. Farms have a natural stock of digestibleorganic material in form of manure or crops for example, which are constantlyavailable.