In recent years it has become more and more evident that man has contributed to much of the climate changes that have taken place during the last century. A major challenge today is to reduce emissions and energy usage at the same time as the global population is growing. To contribute to a better environment, Stockholms Stad has set at target of becoming fossil fuel free by the year of 2050. The construction of new districts is done with this goal in mind; energy efficiency and renewable energy sources are examples of methods to achieve this.Solar energy is considered to be a sustainable energy source and the most common techniques to harvest solar energy in Sweden are solar cells and solar collectors which produce electricity and heat respectively. This report aims to investigate whether an investment in any of these systems would prove to be economically beneficial at Kvarnholmen, a district under construction in eastern Nacka, Stockholm.Since the finished blueprints only cover a small portion of Kvarnholmen, the report examines the possibilities for a house where construction has already begun, Nya Kvarnen.

The world?s growing need for energy together with a desire to ward off the worst consequences of global climate change has resulted in a never seen desire to invest resources in renewable energy sources. Biogas production through anaerobic digestion is one of those growing energy sources. In Sweden there are over two hundred plants that uses this biological process to break down organic substances while producing carbon dioxide and the energy-rich gas methane.This master?s thesis has focused on development of the mixture of different organic substances that is treated at a specific plant, namely Mosserud biogas plant.

The Swedish building and property management sector are responsible for about 30 % of the total energy use. In order to take environmental consideration, different environmental assessment tools and standards are used. Miljo?byggnad, Svanen, FEBY12 and PHI are some of these. There has been increased interest to certify buildings and therefore it is of interest to evaluate the assessment of the energy field to see if relevant energy aspects are assessed.

Glulam?s position at the Swedish market for building constructions has been established over the past decades. Factors affecting glulam demand are found both in global and national contexts as well in customer attitudes and knowledge of the material. Arguments for environmentally friendly and sustainable construction processes and energy-efficient designs are nowadays common, which is something that should motivate increased usage of wood as a renewable material. For the glulam industry to increase its sales, improve profitability and thereby gain market share in present competitive climate, reliable market information and updated market intelligence is required.

European Union has made a new decision that all new built houses by 2020 shallbe near-zero energy houses. Boverket?s definition of near-zero energy housesintends buildings with good energy performance in which a proportion of theamount of energy that must be added to the building is made of renewable energy.Passive House is a set of requirements from FEBY designed to build energyefficient buildings. This is achieved by reducing loss of heat through the buildingenvelope and to take advantage of the passive heat from solar radiation,installation and heat sources like people living in the house.This project has been made with help of Anebyhus and one of their model houseshave been examined from the report?s issues, including Anebyhus?s energyperformance, requirements for the manufacturing and assembly, how theenvelope must be improved to fulfill the requirements for the Passive House andwhat energy calculation programs are available on the market.The report aims to provide solutions for energy efficient houses that are adaptedfor production of house building.Two visits to Anebyhus has been done to study their manufacture and assemblyof building elements.

Because of the increasing trends in energy consumption and increased environmental awareness, greater focus has been placed on improvement and development of renewable energy sources. An already proven and accepted method is biogas production from anaerobic digestion at municipal wastewater treatment plants.In the waste water treatment process solid material and dissolved pollutants are separated from the water, forming a sludge. The sludge is separated from the process and stabilized during anaerobic digestion or aerobic aeration. Most often, mesophilic anaerobic digestion is used. Because of degradation by microorganisms, biogas with a high content of methane is formed during the digestion.

In this thesis a method for evaluating investments in small scale hydro power is presented. An analysis of the future position that small scale hydro production will have on the Nordic electricity market is also carried out. This is done by an inventory of technology and economic and environmental aspects. The inventory is also a guide as to how the project should be implemented.Hydrolyzer is the name of the Excel tool developed to evaluate investments. The tool requests input data from the user and then evaluates the investment and generates a sensitivity analysis.

För att en kvalitativ och driftsäker kraftomvandling från vind till elkraft skall erhållas ställs krav på en mängd olika faktorer. Klimatologiska och tekniska faktorer kräver korrekt dimensionering och anpassning av omvandlingstekniken för att största möjliga energimängd skall kunna omvandlas på ett driftsäkert och energieffektivt vis som vindkraftsägare, nätägare kräver. Vinden är som bekant en oberäknelig kraftkälla. Variationerna i styrka och tid kan innebära en hel del driftoptimeringsproblematik med efterverkningar för vindkraftsverket, nätet och belastningen. Konsekvenserna kan bero på vilken typ av teknik som är installerad i de olika delarna av energisystemet och i områdets elnät.

Combustion of fossil fuels is today the dominating source of energy. During combustion,carbon dioxide is formed. The carbon dioxide accumulates in the atmosphere,which raises the global average temperature on earth through the so called greenhouseeffect. The only way to reduce the emissions of carbon dioxide from combustionin a coal fired power plant is through carbon capture and storage (CCS).Post-combustion capture is a technology to separate carbon dioxide from the uegas after the combustion for efficient transport and storage. The steady state operationof coal fired power plants with post combustion capture has already beenthoroughly investigated on a pilot scale, however much work remains to investigatethe plants dynamic operation.

I samband med en ?kad efterfr?gan och st?rre behov av fossilfri energi kommer storskaliga solcellsanl?ggningar p? mark att spela en allt viktigare roll. Samtidigt kr?vs ett h?nsynstagande till lokalbefolkningen som f?r anl?ggningen placerad i sin n?rhet. Tidigare forskning har visat att b?de ekonomiska, sociala och milj?m?ssiga aspekter g?r att koppla till n?rboendes acceptans.

Green public procurement (GPP) can be used as an instrument to reduce carbon dioxide emissions, and consideration of environmental aspects within public procurement is becoming more common in Sweden and internationally. Two product groups that have been pointed out as especially important are transports and electricity, where the opportunities for public purchasers to reduce emissions are relatively large. This paper studies GPP which aims at reducing emissions, primarily of carbon dioxide, through environmental requirements within these two product groups. A theoretical analysis of cost-effectiveness, transaction costs and effects on technological development is performed, followed by a closer study of how these aspects appear in practice within GPP. The results indicate that a cost-effective allocation of reductions between the two product groups is most likely to be attained if the main part of emission reduction is achieved through environmental requirements on electricity. The cost for emission reduction within transports is relatively high, especially for heavy transports. For transportation services, more generally focused requirements on emission reductions could probably give greater environmental gains, but the existence of transaction costs steer the environmental requirements towards more technology specific types.

Ethanol for automotive purposes is an issue much debated and researchers disagree about the benefits of bioethanol. Converting energy-rich crops into ethanol suitable as motor fuel is a complex process and continuous development and improvements of processes and material used are important steps in the work of developing environmental friendly fuels. Grain is usually preserved by drying which consumes a lot of energy. Alternative storage of high-moisture grain in airtight storage systems reduce the energy required to produce bioethanol and studies have also shown that ethanol yields are increased more than 10% in ethanol fermentations of moist grain compared to dry. Airtight storage is often not perfectly airtight so biocontrol agents are necessary in order to preserve the grain.

A district heating plant has the advantage that it can take advantage of the waste heat from industries and use of cheap fuels to produce heat. But for the long term is competitive requires that energy is also saved in district heating plants. One way to save energy in a district heating system is to increasing cooling to the return temperature. This leads to less power needed to drive the distribution pumps,  and that more energy could be extracted from the same amount of fuel by an improved flue gas condensation.In Karlskoga the return temperature into the district heating plant is high. They would therefore reduce the return temperature in order to extract more energy from the flue gases.

Aquaponics is a food production system consisting of a consecutive cultivation of plants and aquatic animals, fish or shellfish, in recirculating water. The plants feed on the nutritious effluents from the fish tank and bacteria converts ammonia from the fish tank into nitrate that is absorbed by the plants. The plants receive nutrition and the fish gain purified water. The environmental impact of the production of fish meal and fish oil used in conventional fish feed includes a large consumption of fossil fuels with subsequent carbon dioxide emission. The aquaponic system can be made environmentally sustainable and self-supporting if supplemented with a vermicompost/vermiculture for the production of worm protein as a fish feed. Vegetable waste from the hydroponic part of the system can be reused as worm feed in the compost and the protein rich worms can be harvested, dried and grinded and brought back to the aquaculture as fish feed. As a first step in this direction, I have investigated the effect of recycling of vegetable waste in vermicomposts on the growth and number of earthworms (this was evaluated after harvesting). The hypotheses were that earthworms can be cultivated in the vegetable waste and that by adding manure to the vermicompost it is possible to obtain a nutrient content adequate to support a continuous worm harvest, in other words create a vermiculture. Eisenia fetida and Dendrobaena veneta were grown in 20 L bins containing peat mixed with either poultry or cattle manure. The proportions were 70% peat and 30 % manure. Discarded plant parts from lettuce cultivation was added to the vermicomposts (35 g per week) and water was supplied with 0.8 L per week.

In the year 1800, about 5 % of the world population lived in cities (World Wide Fund for Nature, 2012, 3). Today that number is about 70 % in Europe and North America, and in 2050 it is expected to be 86 % in the developed world and 67 % in the developing world (www, UN, 2009). In addition, the global population is expected to increase with 2.2 billion people until 2050. As a result of the population increase more food has to be produced which requires more transport from the countryside to the cities. However, this flow of resources faces some difficulties.