I Sverige står bostads-och servicesektorn för nästan 40 % av den totala energianvändningen och därför har många byggnader behov av energieffektivisering. Arbetet utgår från Eken, en del av Karlbergsskolan i centrala Karlstad, som är en kulturmärkt byggnad från 1890-talet. I byggnaden pågår gymnasieutbildning, förskola samt idrottsverksamhet i en gymnastiksal. Byggnaden ventileras i dagsläget med konstant luftflödessystem (CAV). Behovsstyrd ventilation (DCV) innebär att reglera ventilationen efter närvaro och behov, genom att upprätthålla en bra luftkvalité och termisk komfort och samtidigt effektivisera energiförbrukningen. Syftet med detta arbete var att undersöka hur behovsstyrning med IR-sensorer eller CO2-sensorer kan påverka energiförbrukningen och driftkostnader av Ekens ventilationssystem, samt undersöka hur innetemperaturen påverkas vid CO2-reglering jämfört med befintligt driftfall. Målet var att beräkna årliga energibesparingar (MWh/år) och investeringsutrymme (kr) till utgifter som uppkommer vid ombyggnation av dagens CAV-system. Ett ytterligare mål var att beräkna innetemperatur vid olika fall då förutsättningar som rumsplacering, solinstrålning, utetemperatur och intern personbelastning varieras och beroende på CO2-reglerat eller konstant luftflöde. Energibesparingar avseende energi till fläktar och värmebatterier, beräknades i Excel baserat på olika luftflöden beroende på personbelastning. Investeringsutrymmet beräknades utifrån årliga besparingar av driftkostnader. Innetemperaturer beräknades i en dynamisk simuleringsmodell för tre dygn och tre rum med olika förutsättningar. Energibesparingar för IR- och CO2-reglering av ventilationssystemet resulterade i 53 MWh/år (-44 %) respektive 77 MWh/år (-64 %) jämfört med befintligt CAV-system. Efter 15 år bidrog IR- och CO2-reglering till besparingar på ca 520 kkr (IR) respektive 750 kkr (CO2). Skillnaden på innetemperaturen vid behovsstyrt flöde jämfört med konstant luftflöde var lägre än en grad i majoriteten av fallen. Den största skillnaden på 2,7 °C uppstod en solig dag för ett rum med fönster mot sydost. Behovsstyrning är uppenbart fördelaktigt för byggnaden ur energi- och miljöperspektiv. Investeringskostnaden för de två olika metoderna är troligtvis ungefär lika stora och hur ekonomiskt lönsam investeringen är beror på återbetalningstiden. Luftflödesreglering leder inte till några större problem för rumstemperaturen och i annat fall borde temperaturproblem kunna åtgärdas genom solavskärmning eller temporärt ökat ventilationsflöde. / In Sweden, the housing and services sector accounts for close to 40 % of the total energy use, hence why many buildings require energy efficiency. This study is based on the Eken building, which is a historical building from the 1890s, a part of Karlbergsskolan in central Karlstad. The building operates with a secondary education, preschool and a gymnasium. It is currently ventilated by a constant air volume-system (CAV). Demand controlled ventilation (DCV) involves controlling the ventilation according to occupancy and requirement, by maintaining acceptable indoor air quality and thermal comfort, while simultaneously decreasing the energy consumption. The purpose of this study was to investigate how demand-controlled ventilation can improve energy efficiency and operating costs of the ventilation system in Eken, using either IR- or CO2-sensors, as well as investigating how indoor temperature is affected by reduced air flow due to CO2-controlled ventilation. The goal was to calculate the annual energy savings (MWh/year) and anticipate the investment range (SEK) for expenses incurred in rebuilding the current CAV-system. An additional goal was to calculate indoor temperature due to CO2-controlled airflow or constant airflow (CAV) under different circumstances. We did this by varying conditions such as location, solar radiation, outdoor temperature and occupancy. Energy savings for fans and heaters were calculated in Excel, based on different airflows depending on occupancy. The investment range was calculated on the basis of annual savings of operating costs. Indoor temperatures were calculated with a dynamic simulation model for three days, in three rooms, with different conditions. Energy savings for an IR- or CO2-controlled ventilation system resulted in 53 MWh/year (- 44 %) and 77 MWh/year (-64 %) respectively compared to consisting CAV-system. After 15 years, IR- and CO2-regulation contributed to savings of about 520 kkr (IR) and 750 kkr (CO2). The difference of indoor temperature during the demand-controlled flow rate in comparison to constant airflow, was less than one degree in the majority of cases. The biggest difference of 2,7 °C occurred on a sunny day in a room with windows facing southeast. Demand-controlled ventilation is clearly beneficial from an energy- and environmental perspective. The investment cost of the two different methods is probably about the same range and the economic profit depends on the payback period. Airflow regulation does not lead to any major temperature problems, however if there are any problems they may be addressed by solar shielding or temporarily increased air flow rate.

A method for predicting consumer heat power usage was examined, for the purpose of implementing such a method in simulation models of the district heating distribution network at Stockholm Exergi. This was to enhance the results of such simulations and aid the company’s work with distribution optimization. A method based on power signatures, which are models currently used in many applications, was examined. The method aspired to describe the consumption patterns of consumers over time and temperature, categorize consumers according to these patterns and then implement the results in the simulation models. The addition of a time parameter to the signatures resulted in an improved and more consistent prediction quality. Categorizing the consumers mathematically caused only a minor decrease in the prediction quality and resulted in better prediction quality than the categorization system currently used. Stockholm Exergi is adviced to keep examining mathematical categorization of consumers as such a categorization has several advantages to the one currently used. It is also recommended to examine options to Termis for performing individual consumer predictions as the program is not well suited for it. Such options could be other software or add-ons to Termis which make such predictions more viable.

New buildings today are built with great care and contain modern technology in order to minimize the energy cost and therefore also their upkeep. This project has tried to evaluate the effect of a smart demand-controlled ventilation system which measures the actual airflow demand and adjusts accordingly. By using exact data from a system inside a school and studying the building itself, an accurate model of the school was created. Using this model the demand-controlled system was compared to a conventional, constant flow, system. The results showed that the demand-controlled system reduced the specific energy consumption of the school by 34 % and that the systems components could be downsized to 70 % of the original size. This means that this kind of integration of control technology is a powerful tool to further increase the energy efficiency in buildings.

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When different energy conserving measures are implemented for reducing energy use in buildings and the buildings are connected to district heating systems, it is important that an overall system analysis is made which takes into account the effects of total change of energy use due to the energy conserving measures. The method applied in this thesis uses hourly production data for the different production units in the district heating system in Gävle, Sweden. The merit order of the different production units is dependent on the electricity spot market price. To calculate the merit order, hourly data for the electricity price is used. The marginal production unit can then be determined for each hour of the investigated year. This thesis analyzes five different energy conserving measures in a multi-dwelling building regarding how they affect the marginal production units in the district heating system. For CO2 emission evaluations, two different combinations of heat and electricity conserving measures are compared to installation of an exhaust air heat pump. This thesis also analyzes how the configuration of the electric meter affects the measured amount of self-consumed and produced excess electricity for a single-family house and for two multi-dwelling buildings of different sizes. The results show that the use of electricity is the most important objective to consider. The increased use of electricity for operation of the heat pump contributes to an increase of global CO2 emissions and the electricity produced by the solar photovoltaic installation contributes to a decrease of global CO2 emissions. The results also show that the configuration of the electric meter is important for the single-family house but negligible for the multi-dwelling buildings. The amount of produced excess electricity is high for all buildings, which means that the economic value of produced excess electricity is important for a profitable installation.

I det här arbetet har det undersökts huruvida mängden deponigas i deponin vid Holmby återvinningscentral i Sunne är tillräcklig för att täcka värmebehovet för ett antal lokaler i närheten, om deponigasen kan ge säljbar el, och om detta kan göras ekonomiskt lönsamt.  De processer som har undersökts är en gasmotor, en gasturbin och gaspanna från Biogassystems och en Stirlingmotor från Cleanergy. Dessa har tillsammans med en ackumulatortank simulerats för att undersöka om de kan klara av att leverera den värme som behövs för att täcka behovet utan att bli för dyra och vilka utsläpp det resulterar i. Det finns i dagsläget ett uttagssystem för deponigasen och all energi facklas i nuläget bort. Energin borde tas tillvara då den kan ersätta andra mer miljöskadliga energikällor. Utöver resultaten i det här arbetet tillkommer kostnaderna och miljöpåverkan för distributionen av den producerade värmen och elen. Arbetet är upplagt så att det produceras den värme som behövs för att täcka värmebehovet. Värmebehovet styr därmed hur mycket el som produceras, då ingen el produceras när det inte finns något behov av värme och den el som inte används till eget bruk säljs. För beräkningar har programmet Matlab och funktionen Simulink använts. Det visade sig att alla metoder med deras respektive verkningsgrader och andra begränsningar klarade av att producera värme i den grad att de klarade att täcka det värmebehov som satts upp samtidigt som en hel del el skulle kunna säljas med tre av metoderna, dock inte med gaspannan då den inte producerar någon el överhuvudtaget. Gasturbinen blir klart dyrast på grund av dess höga pris och låga el-verkningsgrad. Det är därmed tveksamt om det skulle vara lönsamt att satsa på en gasturbin som lösning för att ta om hand om energin i deponigasen. Den rekommenderade lösningen är att använda sig av en gaspanna om det inte finns något intresse av att sälja el då den utan några problem klarar av att leverera den värme som behövs samtidigt som den är billigast. Om det däremot finns ett intresse av att sälja el hade en stirlingmotor varit att föredra då den klarar av värmebehovet samtidigt som den producerar el som kan säljas. Detta i kombination med att den inte är lika känslig för föroreningarna i deponigasen som gasmotorn gör den till det bästa alternativet för en kombinerad värme- och elproduktion. / In this study a evaluation has been conducted to whether the amount of landfill gas in the landfill at Holmby recycling station in Sunne could be used to cover the heat needed to heat up a couple of buildings nearby, how much electricity that would be produced in the process and if there would be any economic gain in doing so. The machinery used in this study is a natural gas engine, gas turbine and a gas fired boiler from Biogas Systems and a Stirling engine from Cleanergy. These have been evaluated together with a heat storage tank to see if they could produce enough heat for the buildings. The system in place today only uses a torch to dispose the gas and no energy from the gas is used. The energy in the gas should be taken care of because it could replace other energy sources that are worse for the environment. Beyond the results in this study you will have to consider the distribution of the produced heat and electricity. The main thought is that you will produce the heat needed and sell the electricity you don’t use yourself. The calculations have been conducted in Matlab and the tool Simulink. The results showed that you can produce enough heat with all the examined apparatuses, with their efficiencies and other restrictions at the same time as you could sell a fair amount of electricity by using three of them, the only exclusion is the gas fired boiler as it doesn’t produce any electricity. The gas turbine becomes very expensive due to its price and the relatively small electric efficiency. It is a possibility that you won’t make any money from a system with a gas turbine. A gas fired boiler is the recommended machinery if there is no interest in electricity production due to its ability to produce the heat needed at the same time as it is the cheapest of the tested machinery. If on the other hand there is an interest in electricity production the Stirling engine would be the recommended machinery. The Stirling engine manage the heat needed in the buildings at the same time as it produces electricity that could be sold. The reason that the Stirling motor is the preferred machinery in this case is that it is not as sensitive to the pollutions in the landfill gas as the natural gas combustion engine.

Efficiency of a ground source heat pump with thermal capacity of 6 kW determined in two differentlocations in Sweden. In the north side with low average temperature which could go down to -10 ᵒCand in the south side, with low average temperature with +2 ᵒC. The heat pump has refrigerantR407c, which could be connected to both, ground source heat feeding methods the horizontal, andthe vertical model. The heat pump give heat for both space heating and domestic hot watercompared the micro CHP which has thermal capacity of 12.5 kW and electrical capacity of 4.4 kW. Ithas IC engine which means the engine has internal combustion work. It also works with two kinds offuel, natural gas and propane MOZ 92; the energy and exergy of the fuel in micro CHP feeding thethermal process by heat. That heat used for space heating and domestic hot water after going outthe process for the cooling which keep the heat in storage tank and it heat the liquid to the gas to beused in the turbine to produce the electricity. The two locations in the north and south of Swedenwill influence the thermal operation and that influence power used for compressor for heat pumpand somehow the pump in the micro CHP. The study shows that the different in exergy and energyefficiency between these two heat technologies by located them in the locations. Higher efficiencyof the micro CHP which give the advantage of use Micro CHP some technology give the benefit byusing the fuel for producing the heating and electricity , the benefit which give the customer manybenefit shows in the study. That’s comparing with the heat pump which is large use in Sweden. Inthis paper will introduce Micro CHP as heating technology which has been used in the rest of Europecould be used in Sweden for future heating technology with electricity producing, shall change thecostumer from energy consumption costumer to producing costumer.

Energy consumption rises continuously every year. Globally, buildings count for half of electricity consumption and 20%-40% of total energy consumption. Building energy sector consumed 40% of total energy use in Sweden. The vital of reduce energy consumption is to enhance building efficiency. This energy audit work investigates how energy consumes of kindergarten building in Vallbacksgården. Then give out cost effective suggestions to improve energy efficiency for object building. The result shows total amount of energy input of the building is equal to 241.9 MWh. While district heating takes the largest part of energy input that correspond to 188.9 MWh (78%), and cost around 123500 Kr annually. Furthermore, energy 38.0 MWh (16%) is contributed by solar radiation, which becomes second largest source of energy input. Finally, internal heat generation is the smallest contributor of energy input which counts 15.0 MWh (6%). For energy output, majority of heat loss is leaded by transmission losses. It cost 190.4 MWh per year that shares 79% of total energy output. Nature ventilation losses of object building shares 17% of total heat output which is 41.7 MWh. Mechanical ventilation and hot tap water have energy consumption with 7.8 MWh and 2.0 MWh respectively. They take rest 4% of total energy output. According to the finding, several reasonable suggestions will be given. Firstly, for the costless solution, decreasing indoor temperature 1℃ or 2 ℃ is able to reduce heating demand 9.0 MWh or 18.1 MWh annually. It will reduce CO2 emission 131859g- 266070 g, and save 5274 – 10642 SEK per year. Secondly, substitute district heating systems by ground source heat pump is an environmental solution. Using ground source heat pump has priority of environment, which lower CO2 emission 1909200 g/year and save 68262 SEK/year by analyze. Investment for this solution is 979000 SEK and the payback time takes 14.3 year. Replace old windows is a moderate solution of cost. Substitution by using energy glass can reduce 20.9 MWh heating demand and 307377 g CO2 every year. New energy glass windows can cut 13591 SEK for district heating every year. The renovate investment and payback time are more than 159732 SEK and 11.8 year respectively.

Renovating roofs of multi-family buildings with building integrated photovoltaics (BIPV) poses a possibility of cost effective installation of solar cells. The surplus electricity could however become a problem for the grid and decrease the profitability of the investment. In this study, the economical possibilities for a BIPV renovation and for batteries and a thermal storage to store the surplus electricity is evaluated. A study has been made for a multi-family building in Jönköping which is built within the time period of the Swedish Million Programme. Several cases were examined where the renovation was combined with installation of BIPV, a heat recovery system (HRV) or heat pump and a possibility of batteries and/or thermal storage. The management of surplus electricity was modelled and the net present value (NPV) for the cases as well as the value of energy storage was calculated. The NPV was positive for all the cases with BIPV renovation, which means that the BIPV renovation is profitable. The alternative cost for the renovation was seen to have a big impact on the profitability. Both the batteries and the thermal storage decreased the NPV and are therefore not profitable today. To increase the profitability of energy storage the investment cost must decrease and/or the energy prices increase. Other possibilities to increase the profitability of the investment was found; to make use of the different political support systems, or to have a group subscription where also the household electricity can be supplied by the solar production. / Miljontak - takrenovering med solceller

Eolus recently developed, sold and now manage a wind farm consisting of four 2 MW wind turbines located in the northern half of Sweden. Soon after commissioning it was noticed that they were underperforming in terms of production and availability. It was suspected that one turbine was underperforming relative to the manufacturers’ power curve. Furthermore, the de-icing systems were discovered to be problematic, causing a lot of unplanned downtime. The main goals of this project are to determine the causes of the discrepancies in availability and production at the wind farm. As part of the investigation, the malfunctioning de-icing systems are also investigated. Initially, the background of the wind farm was researched. Important contracts, maintenance reports and other documentation was reviewed. Moreover, interviews were performed with four people involved with the wind farm. These revealed that problems first began during the construction phase. Delays and poor construction quality in general led to problems being carried over to the operations stage. Complications with the de-icing systems and blade drainage holes contributed to underperformance during the first year of operation. The second year of operation was marked by the de-icing system electrical cabinet detaching in the hub of turbine 2. Analysis of the turbine data and status files confirmed and elaborated on the information provided by the qualitative analysis. Investigation of the production and lost production figures revealed that the main problems have been related to the pitch systems, low temperature kits, sonic anemometers, PT-100 sensors, and the software for the controllers. Furthermore, a significant proportion of the lost production and downtime in years one and two can be attributed to tests and repairs performed on the de-icing systems. However, early indications in year three suggest that the single active de-icing system in turbine 3 is functioning as it should. Year three began with a significant improvement in availability, all turbines have experienced monthly availabilities of at least 90%. Overall, it appears that the fact that only one de-icing system is active has had a significant impact on the availability and production figures. However, organisational issues with the manufacturer still need to be resolved, as do the technical issues.