When a combined heat and power plant produces heat and power it often faces a deficit of heat load during the summer or other periods of time. This heat is often unnecessarily cooled away or the power production has to be reduced or shut off. If it is possible to store heat from periods with low heat demand to periods with high heat demand one can get many benefits. Among these benefits are: increased power production, decreased operation with partial load, uniformly distributed load.To be able to store heat in situations like this long-term thermal heat storages are needed. In this thesis five different types of stores are presented: rock cavern storage, tank storage, pit water storage, borehole storage and aquifer storage.

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.

In today?s society a large focus is put on energy systems and how our energy systems are built up. In order to make sure that we in the future still can enjoy the living standards that we are used to today, Sweden and EU have made a number of decisions on making our energy system more energy efficient and consequently reduce the usage of energy resources. By 2020 the European Union should have reduced its energy consumption by 20 % compared to 1990?s level, and by 2050, 50%.

Cooling down the indoor air can be done in several ways. One way is desiccantcooling which will be used at the Stockholm Arena. This method is used in airhandling units that use temperature changes and moisture fluctuations in the air. Oneof the steps is to add heat during the cooling process in order to reduce the relativehumidity of the exhaust air. The air passes thru an adsorptions rotor which thenabsorbs moisture from the supply air.

Due to increasing regulations regarding new diesel vehicles particulate matteremissions the new Scania truck, Scania Euro 6, has been equipped with a particulatefilter. This component effectively stores the particles in the exhaust gas but must becleaned in order to prevent itself from clogging. The filter is cleaned through aprocess named regeneration which is a thermodynamic process in which thetemperature of the filter is raised through fuel supplied to the exhaust gas.The purpose of this thesis is to contribute to the development of improved controlstrategies of the temperature during the regeneration process through thedevelopment of model-based controllers. These controllers are designed in order tohave good performance in stationary as well as automatic regeneration.In order to develop these model-based controllers a model of the system isconstructed. The model is described as a linear thermodynamic grey-box model withflow varying parameters, showing good results in validation.The model provides a simulation environment during the controller design, which isfocused around the development of linear regulators with the exhaust gas mass flowas a scheduling variable whose size determines controllers? mode of operation.

The smelting process at Sapa Profiler AB in Sjunnen generates large quantities of waste heat which is absorbed by the cooling water when the aluminum is cooled down. This paper is the result of a Master?s Degree Project aiming to present the conditions for recycling the waste heat. The cooling water absorbs the heat from the aluminum at an average rate of 600 kW and the paper shows that it can be used to replace electrical power consumption for heating the production plant?s facilities.

We are heading towards a huge switch of how energy is produced with fossil fuels being replaced by renewable energy sources. It is not difficult to replace the energy you use in the house and there is no need for futuristic technology. There are already many established products on the market such as high efficiency vacuum solar collectors, heat pumps & small wind power stations that can supply the energy being used in a house. The company Sol & Energiteknik SE AB in Huskvarna has many different products which can reduce the need for an outside energy distributor. An average house in Sweden uses 15 000 kWh for heating, 5000 kWh for tap water and 5000 kWh for electricity.

Denna rapport har undersökt om game metrics genom heat maps kan användas för att hitta en choke point i en bana gjord till spelet Team Fortress 2. Game metrics och kvantitativa  metoder  erbjuder  ett  objektivt  och  nästan  automatiserat  alternativ  till kvalitativa metoder när det kommer till balansering. En bana har konstruerats med en choke point och har speltestats för att generera en heat map. För att undersöka om det går att hitta en choke point med hjälp av en heat map så har en enkät gjorts där respondenter   bads   hitta   choke   pointen   med   hjälp   av   den   heat   mapen   som genererades från speltestningen av banan. Alla respondenter lyckades hitta mitten av choke  pointen  med  hjälp  av  heat  mapen.  I  framtiden  skulle  arbetet  kunna  utökas genom  att  undersöka  om  användandet  av  bottar  eventuellt  skulle  helt  kunna automatisera  balanseringsprocessen.  Det  skulle  också  gå  att  undersöka  hur  olika klasser rör sig i en bana..

Due to increasing regulations regarding new diesel vehicles particulate matteremissions the new Scania truck, Scania Euro 6, has been equipped with a particulatefilter. This component effectively stores the particles in the exhaust gas but must becleaned in order to prevent itself from clogging. The filter is cleaned through aprocess named regeneration which is a thermodynamic process in which thetemperature of the filter is raised through fuel supplied to the exhaust gas.The purpose of this thesis is to contribute to the development of improved controlstrategies of the temperature during the regeneration process through thedevelopment of model-based controllers. These controllers are designed in order tohave good performance in stationary as well as automatic regeneration.In order to develop these model-based controllers a model of the system isconstructed. The model is described as a linear thermodynamic grey-box model withflow varying parameters, showing good results in validation.The model provides a simulation environment during the controller design, which isfocused around the development of linear regulators with the exhaust gas mass flowas a scheduling variable whose size determines controllers? mode of operation.

The exhaust arrangement on a Scania V8 consists of one manifold at each bank connected to a twin entry turbine (8-2-2). A study in GT-Power has shown improved performance and reduced cylinder to cylinder variations using two manifolds at each bank in combination with a single entry turbine (8-4-1). This thesis work analyses the difference in performance shown in simulation and verify it by engine test.The initial work was focused on simulation in GT-Power. Investigating how exhaust manifold volume and pulses effects the turbine efficiency and the mean effective pressure during the gas exchange. To verify GT-Power simulations four engine tests with different exhaust arrangement have been made.The results from GT-Power simulation indicate that a larger exhaust volume improve the turbine efficiency.

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 present climate discussion has made energy efficiency an interesting topic. Saving energy does not only help the climate but also saves money for the energy consumer. The purpose of this thesis was to examine the potential of heat recovering from milk cooling. Two milk farms, one with voluntary milking system, VMS, and the other with conventional milking system was used to measure interesting temperatures and electricity consumptions. The numbers were used both to do theoretical calculations and to construct a SIMULINK model. To calculate the potential for heat at milk farms theoretical calculations were made in MATLAB using a reference farm with different combinations of heat recovery and pre cooling. The farm was assumed to keep a dwelling house with the annual heat consumption 18165 kWh.

When cows in Sweden are inseminated the heat strength is reported to the Swedish milk-recording scheme and AI scheme. Cows that show strong signs of estrus are desirable and the trait is included in the Swedish breeding goal. A strong heat makes it easier to inseminate at the right time and to avoid long and expensive days open. Since ten years the heat strength is scored from one to five by the farmer and reported to the milk-recording scheme and AI scheme. Earlier the score was from one to three and the decision was made by the AI technician.

Understensho?jden is Stockholm's largest eco-village which was built in the early 1990s with the vision of enabling ecological living for people. However the ecovillage is no longer considered as environmentally friendly because of its relatively high energy consumption, and non-updated energy system. The purpose of this study is therefore to investigate how Understensho?jden should reduce their energy consumption and upgrade its energy system by using Blower-Door, IR-camera and Design Builder.

The urban heat island is an area restricted to a city center where the temperatureis higher than its surrounding environment. The greatest temperature difference isfound at night when the weather is calm and the sky is clear of clouds. There are twomajor causes behind this phenomena and the first one is the use of energy forheating of houses. The heat leaks through the walls of the buildings and warms upthe surrounding mass of air. The second one is the use of building material whichstore the suns radiation on daytime and releases the heat during night.