In the spring of 2014 Sweco Systems AB were commissioned to design a ventilation system for a newly built preschool in Linköping. Terms from the client was that it cost efficiency would cope with the energy demands that are placed on the building. The unit chosen was a cross-flow heat exchanger, and this work is to compare it with two other heat exchangers to see if a more energy and cost efficient could have been chosen. The heat exchangers that was chosen for the comparison was a rotating- and a counterflow heat exchanger. Simulations have been made to the different heat exchangers by the manufacturers.

When the Swedish Forestry Act was changed in 1994, brushing of young stands became non mandatory. Since then the annual need for brushing in the country has increased by about 100 000 hectares per year. In later years the price for biomass energy has increased to the same level as pulp wood. The high price on biomass energy and the large areas of stands in the need of brushing has created a new market with its own technical, economical and environmental conditions. There is a development of various techniques to manage the forestry stands with late brushing.

Miljöfrågor är i dagsläget ett ämne som intresserar och engagerar mångamänniskor på olika plan och inom olika ämnesområden. Kraven från vår regeringoch från EU blir allt stramare och inom området byggteknik finns idag krav på enbyggnads specifika energianvändning vid nybyggnation. Problemet är att det intefinns något specifikt krav på det befintliga beståndet och dessa byggnader har oftahög energiförbrukning. Möjligheten att det inom en snar framtid kommer kommakrav på det befintliga beståndet, likt det som finns för nybyggnation, är inteorimligt. Det är därför viktigt att redan nu se på vilka åtgärder det finns att vidtaför att sänka energiförbrukningen hos äldre byggnader och som riktlinje strävaefter att nå det krav som ställs på nybyggnation.Det finns många möjligheter och tillvägagångssätt till att energieffektivisera detäldre beståndet av bostäder.

The research in this paper aims to producing a home version machine thatcan dry and make biological waste into compact pellets. This product ismade primarily for those who want to improve the environment and reducethe energy consuming process of separating the biological leftovers fromother waste in the large processing plants and save money due to reducedpickups of waste. Since there is no commercially available product thatdoes what we want to achieve we had to start from the beginning with boththe design and the mechanical aspects. The result is a machine, that fits inour homes, and in an easy and inexpensive way reduces the amount ofbiological waste that needs to be collected by the public wastetransportation system. This is done without reducing any of the energy inthe waste and it can still be used to compost or by large-scale plants that usethe waste to make electricity.

The sun is an endless energy source and the heat it produces can be used to heatup our homes. This technology is relatively old and was introduced in the late70-s. There are two kinds of solar collectors that are most frequently used todayand these are plain solar collectors and vacuum solar collectors. The plain solarcollectors are the once that are used the most but the vacuum solar collectorshave increased more as a percentage the last couple of years.The biggest question asked regarding an investment in solar heating is if theplant is economically profitable. This question has no direct answer because itis dependent on a couple of prerequisites.

This thesis is a case study that examines what political decisions have been taken and how these policies have been implemented. Further this thesis discusses how legitimacy of local policy makers and implementors is affected. The subject studied have been the social service of Jönköping municipality and the intervention of safe-housing aimed at women who have been, or are subject to violence by person close to them. In our study we have examined local policy within the territory of the intervention and how this policy is implemented. A qualitative method with semi-structured interviews was used in combination with quantitative methods to examine protocols from the social welfare board and an action program named "Skydd och stöd för misshandlade kvinnor och deras barn? [Protection and support for abused women and their children].The purpose of this study has been to highlight how the social services implemented the local policy of safe-house accommodation in Jönköping municipality from the legitimacy and discretion perspectives.

During 2007 the City of Stockholm installed five grid connected photovoltaic systems. The aim of this master thesis is to quantify the amount of produced energy and recommend routines to collect and analyse production data, to make production data accessible by the public and to gain experience for future installations.The total amount of produced energy until March 2009 is 227 000 kWh, with an annual rate of 150 000 kWh. The expected annual rate was 148 000 kWh.All system owners are positive about their plants and see economical benefits in scaling up such systems.The installations need very little attendance and maintenance, however it is recommended that an alarm function is installed for automatic feedback in case of a system failure. All future systems should be inspected during full operation to determine if the actual capacity is matching the installed capacity..

Skärgårdsstiftelsen, which is responsible for several of the archipelago islands in Stockholm, has chosen to explore the possibilities for more sustainable heating systems in buildings on the islands in collaboration with KTH. A reduction of energy use and improving the efficiency of existing heating systems are included as part of the environmental work. This report studies the island of Grinda, which is located outside the area of Vaxholm in Stockholm. The study area consists of a guesthouse consisting of a restaurant as well as conference facilities and four neighboring cottages used for overnighting. The cottages now run solely on direct electricity, both for heating and hot water.

The consumption and energy use in today's society contributes to the on-going climate change that creates a debt of life quality for future generations (www, DN, 2007, a). The resources that are used by humans exceed by far what is sustainable (www, Regeringen, 2007, a). The purpose of this paper is to examine how a message about energy conservation should be designed to reach youths. This will be attempted by showing their thoughts on energy and environmental issues and also what it would take for them to get more involved in these issues. The views of the youths are gained by a number of focus group-interviews, which where carried out in the fall of 2007, with kids in the ages 12 to 19. Apart from these interviews, interviews where also conducted with representatives from different youth organisations in Sweden, which gave their views on how to get a message across to kids.

I detta examensarbete studeras kommande energikrav för byggnader i Sverige och i synnerhet kraven påspecifik energianvändning. Detta mot bakgrund av EU-kommissionens och EU-parlamentets direktiv,EPBD2, om nära nollenergibyggnader 2020. Därefter bearbetas ett förslag på en nyytterväggskonstruktion som med lägre U-värde än den befintliga ytterväggen ska sänkaFiskarhedenvillans olika hustypers specifika energianvändning. Syftet med sänkningen är att möjliggöraför Fiskarhedenvillan att uppfylla de kommande energikraven.Det är många parametrar som måste uppfyllas och det nya ytterväggsförslaget analyseras förutom urenergisynpunkt även med hänsyn till statik, fukt och kostnad. Beräkningar för statik och specifikenergianvändning har gjorts för ett referenshus.Resultatet av att byta ut den befintliga ytterväggskonstruktionen mot det framarbetade förslaget medca 33 % lägre U-värde gav endast en sänkning med ca 6 % av den specifika energianvändningen.

The development of solar photovoltaic (PV) is increasing,with declining module prices and with a strongenvironmental profile. Policies are developed around theworld to achieve the targets set for renewable energy.In Helsingborg, the local power company Öresundskraft isworking with solar PV to achieve the goals of the city.With their vision: - Energy for a Better World and Powerfor the Region, their work with developing the local solarPV market is continuing and the next step is to create asolar PV policy. Today their offer is 1 SEK/kWh for theexcess electricity delivered to the grid.It turns out that compensating the customer is a vitalpolicy and it has to be dynamic to follow the decisions ofpolitics. The same survey shows indeed, thatenvironmental and technical part is of interest. Solar PVwill be supported locally to act on environmentalsustainability and locally produced electricity and withthis Öresundskrafts vision will be achieved..

Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods.

During the last decades the housing sector has increased continuously, and housings and services accounted for 40 % of the energy usage in Sweden during 2011. The expansion in number of buildings in society has resulted in an increase in both energy usage and emissions of greenhouse gases. It is crucial to enable a sustainable development of society and as a result, the demand to reduce the emissions of carbon dioxide is a current question. In this study, the carbon dioxide emitted from the housing sector in Stockholm is estimated. The housing sector can be divided into different types of houses such as apartment blocks, single-family houses and holiday houses. By collecting information of the energy purchased in respective households, a computational model is generated that calculates the total emission of carbon dioxide.

Emissions of insufficiently treated wastewater, mainly blackwater (i.e. wastewater from toilets), contributes to the eutrophication of lakes and seas. At the same time, blackwater is a fraction with a low content of heavy metals and, after sanitization, it can recirculate plant nutrients to arable land using the liquid composting treatment method. Liquid composting means that organic material is degraded under aerobic conditions. For sanitization, the blackwater needs to be treated together with energy-rich complementary material.

The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.