In a sustainable society the use of renewable energy and recycling of materials is of high importance. Wastewater treatment plants use large amounts of energy in the processing of wastewater. This study seeks to evaluate wastewater as an energy resource and to examine treatment plants potential to become sustainable energy producers. The study is based upon the internal processes of Himmerfja?rdsverket.

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

Increased energy consumption in the world has created an increased supply of various fuels, especially fossil fuels. The Swedish government has set up various energy targets for 2020. To reach these goals it?s important to increase the energy efficiency in local buildings such as schools. This work illustrates the breakdown between energy supply and energy losses over the school.

The building industry consumes approximately 40 % of the total energy consumption in Sweden, where the using stage is dominating with 80 %. There is a lot of work in progress to reduce energy use in the building industry, and the demands from authorities regarding energy use increases. As a part of this work Building and planning department of Sweden has established a requirement that has been applied since 2006, and restricts a maximum energy use for buildings.The requirement includes that an energy simulation must be done in advance to demonstrate that it is possible to meet the demands.Reality is however more complex than an energy simulation program, that frequently underestimates the energy use of buildings. The purpose of this thesisis to study and analyse deviations between estimated and actual energy use in modern apartment buildings. The study includes four apartment buildings in Stockholm, Gothenburg and Jönköping that were built in 2007-2009.

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

Former studies have shown that a considerable part of industries? energy usage can stem from idle times in the production. This thesis, carried out at Siemens Industry sector, evaluates the potential for using the control system to automatically put machines into energy saving mode during idle times. The main part of the thesis consists of a case study performed on machine tools at a Scania production site in Södertälje. Through load measurements the potential for energy savings was determined.The results show that there is a great potential for energy savings during idle times at the site.

The purpose with this report is to examine how the implemented energy efficiency measures on Bokelundskolan in Växjö have had impact on the energy use. The measures which have been implemented are, new ventilation system, new heating system, optimized adjustment of the heating system, new windows with U-value 1.2 and lower window height, insulation under windows and in the crawl space. The school's energy use before and after rebuilding has been calculated with the calculation program, Vip-Energy 1.5.5.Calculations of energy use for the school with windows on U-value, 0.9 and 0.7 have also been done. The replacement of windows has been studied from a cost perspective. The conclusion is that the exchange of heat and ventilation system was the biggest contributor to reduced energy use on Bokelundskolan.

As demand for renewable energy is increasing rapidly, the market for biomass pellets is expected to continue to grow in the near future. Most of the new raw materials that are discussed for pellet production have one thing in common; the production costs will increase compared to using traditional raw materials such as sawdust and planer shavings. The aim of this thesis is to investigate to what degree increased use of new raw materials for pellet production will affect the general pellet prices in Sweden and to survey what plans Swedish pellet producers have concerning new raw materials. To investigate the raw material situation of the Swedish pellet producers an industry survey was performed. Literature studies were also made on previous research in the subject field. Calculations of the production costs for pellets were done for the raw materials sawdust, wet sawmill chips and energy wood respectively. New raw materials are already used by the large-scale pellet producers in Sweden.

Energy awareness is growing among the Swedish population and a one­?to­?two-family dwelling can save energy. The purpose of this paper is to design a tool that helps these home owners reduce their energy costs.The paper develops a model that gives them an indication of how much energy they can save. For the majority of homeowners, the next step in the quest to reduce theirs is most likely an energy audit. Therefore, information to help home owners to get a good energy audit performed is included in the model.A prototype running the operating system iOS is created and validated against existing models, as well as an energy audit. .

Today, buildings utilize 40 % of the total energy consumption. New energyrestrictions and directives have entered the construction industry. Photovoltaic is asustainable, clean and quiet solution that integrates well in the urban environment buthave not yet reached a breakthrough on the Swedish market. The conditions for solarenergy production are often set in the early planning stages where they rarely arebeing prioritized.This master of engineering project focuses on identifying problems regardingimplementation of photovoltaic in city development projects and giving suggestions topossible improvements in the planning- and construction process. It also givesrecommendations on how the conditions for energy production can be optimized inthe early zoning stage.By conducting simulations with PVsystV5.21, on three ongoing city developmentprojects in Umeå, Malmö and Stockholm and by carry out and analyzing interviewswith city planners, constructors and architects, some conclusions have been made.Several improvements, both politically, with changes in the subsidization systemand/or instatement of a new law with feed-in tariffs, and within the solar- andconstruction industry itself, with better communication between different parts of theprocess as well as better use of experience, can be made.

To build a sustainable future should we first understand that; every aspect of our daily lives can affect the environment. It?s important that we take responsibility for understanding how we impact the environment and change our actions accordingly. The worlds total energy consumption equivalent to 80 million MWh / year. This corresponds to about 220 million MWh / day.Energy consumption is one of the main reasons for increased greenhouse gases when the reduction of this consumption has a great demand worldwide.In order to prevent the energy that consumed the buildings must be energy efficient but there is a conflict between radon ventilation and energy conservation in a building, given that ventilation can consume as much energy (currently 29-59% of energy-efficient houses use), especially in a cold climate as in Norway.

The purpose of this study was to implement an energy analysis and environmental evaluation of the property Hemsta 12:16 in Gävle. Based on two different methods, Energy Balance calculation and Environmental Building, the result of the property's energy use, energy performance and environmental impacts are presented. Except that, measures to reduce final energy consumption are presented.      The proposed measures can reduce energy usage by 100 400 kWh / year, which represents a decrease of 18% of the present energy usage. This would represent a total savings of 63 000 SEK per year. In addition, the environmental performance is improved by adopting the suggested measures..

The question of excessive global energy use needs to be solved. All energy production and usage have negative environmental impacts, which are best solved by reducing energy consumption and by using energy more efficiently. A large part of the Swedish energy use is concentrated to the building sector and to reduce the total energy consumption real efforts need to be made to make buildings more energy efficient.The aim of this study was to investigate how energy is used in one of Göteborg University?s buildings and to find measures that can be taken to improve its energy efficiency. The chosen building Zoologen, is used for research and education.The main method of the study is computer simulations of the present building and of possible energy reducing measures to be made in the future.

In modern society in terms of economics and environmental impact, it is important to ensure that a company is as energy efficient as possible to reduce the amount of energy used. About 10 TWh of electricity used annually to pump drives in Swedish industry. Therefore, pumping system has great potential for energy savings.The objective of this report was to determine how much energy and money that can be saved with the insertion of variable speed drive to six pumps on Bleach plant 4 in Skutskär Mill. The work was performed with electrical measurements during one week, analysis of pump curves and the compilation of production data over a year.The results show that four of these six pumps were profitable and yielded an annual saving of 1172 MWh of electricity and 560 000 SEK. With an economic lifetime of 10 years and a discount rate of 6.8% the final result for the entire life-cycle savings became 3 355 000 SEK.

The project was performed at SiemensIndustry Drive Technologies with theobjective to provide actual values forthe energy savings potential withinSiemens scope of practice.In Sweden the electrical drives standfor about 30 % of the total electricityconsumption and about 60 % of theelectricity consumption within theindustry. During the pre-study phaseelectrical drives with pump applicationswere identified as large energy users.Because of this a case study at one ofSiemens customers, Stora Enso Fors wasperformed. The system that was evaluatedduring the case study was a throttledsystem with a centrifugal pump forpumping pulp.The results yielded that a saving ofover 50 % could be achieved by replacingthe throttle valve with a variable speeddrive, a frequency converter. Thepayback period was two years and twomonths and the present value for thetotal life cycle cost of the variablespeed system was 662.566 SEK lower thanfor the throttled system. As aconsequence, Stora Enso Fors is advisedto invest in a frequency converter forregulation of the system.The general conclusion is that a focuson system efficiency is the mostimportant factor in energy efficiencyprojects and that the system regulationmethod has a large impact on the overallsystem losses and hence its efficiency.Energy efficiency potential forthrottled systems with centrifugal pumpsis large and significant economicalsavings can be made through investmentswith short payback time..