The purpose of the project has been to work out recommendations that reduce the energy-related costs and environmental impact of HPW Fresh & Dry Ltd., a fruit drying factory in Ghana. The factory produces electricity with diesel and biogas but also purchases electricity from the national electricity company. Heat for the drying process is produced from biogas, kerosene and solar panels. In the project the energy system was analyzed by measuring production and consumption of heat and electricity. The project results show that the factory can become self-sufficient on heat if the available energy is used more efficient. The production units for both electricity and heat have low efficiencies.

If a building is heated by a heat pump, it is of high importance that the heat pump has a high coefficient of performance. An exhaust air heat pump extracts heat from the building?s exhaust air. The air has a relatively high and constant temperature all year around, leading to a high seasonal coefficient of performance. This thesis examines whether it is profitable to complement an exhaust ventilation system with an exhaust air heat pump in an apartment block that already has geothermal heat pump, district heating, oil- or biofuel heated system.

The purpose of this thesis was to make an energy survey and quantify energy flows of individual unit operations associated with the biogas production in Uppsala Vatten och Avfall AB:s biogas plant, located at Kungsängens gård. Moreover, large consumers of energy would be identified and analyzed. The objective of this energy survey was to obtain a detailed understanding of the energy use in the biogas production.The energy survey was divided into two parts: electricity and heat. Each part was treated separately and with somewhat different approach. To estimate the electricity usage during the projcet the rated power of each selected unit operation was noted and multplied with thenmeasured time of usage.

The purpose of this thesis was to make an energy survey and quantify energy flows of individual unit operations associated with the biogas production in Uppsala Vatten och Avfall AB:s biogas plant, located at Kungsängens gård. Moreover, large consumers of energy would be identified and analyzed. The objective of this energy survey was to obtain a detailed understanding of the energy use in the biogas production. The energy survey was divided into two parts: electricity and heat. Each part was treated separately and with somewhat different approach. To estimate the electricity usage during the projcet the rated power of each selected unit operation was noted and multplied with the measured time of usage.

This master thesis was carried out for Saab Avitronics, a business unit of Saab ABactive in electronic systems for military aircrafts. Reliability and weight are of crucialimportance in this environment. To improve reliability and lower the weight graphitemay be used for electronics cooling. Graphite is an anisotropic material and hasthereof high thermal conductivity in two directions (in-plane) and a relatively lowconductivity in the third direction (through thickness).The purpose of this thesis was to investigate if graphite is an adequate thermalconductor to use in PCB carriers. The carriers support and cool the PCB by divertingthe heat dissipation from the PCB components to the edge.

Geothermal energy can be extracted from an aquifer, where the groundwater is used as heatexchange medium while heat and cold are stored in the surrounding material in the aquiferand to some extent in the groundwater. Application of aquifer storage for the use ofgeothermal energy is mainly used in large scale facilities and is limited to sites with suitableaquifers in the form of ridges, sandstone and limestone aquifers.Löwenströmska hospital in the municipality of Upplands Väsby, north of Stockholm, islocated nearby the northern part of the Stockholm esker. This means that it can be profitableand environmentally beneficial for the hospital to examine the possibilities of aquifer storagein the esker material next to its property.The purpose of this master thesis has been to investigate if geothermal energy storage with aseasonal storage of heat and cold can be applied within Löwenströmska hospital?s propertyarea using groundwater modeling. A hydraulic groundwater model was constructed inMODFLOW based on a simplified conceptual model of the groundwater system.

Grubbe Ventilation AB is a sheet metal and ventilation company who provides design, installation, service, and repair of ventilation. The company is expanding their business by building a new facility in Umeå, Västerbotten. The property is designed to be used for both office and industrial work.Grubbe Ventelation AB has not yet decided upon wish system which is to be established to provide the building with heating and cooling. The consulting firm Umeå Projekt Team has therefore been asked to investigate the possibilities to invest in geothermal- heating and cooling.If the investigation of a geothermal heating- and cooling system would provide favorable results it would be a very appropriate alternative that provides energy at low costs and are an environmentally friendly option as the energy comes from stored solar energy in the ground is provided by stored solar energy in the ground.The facility ´s heating and cooling consumptions are calculated in the program BV2 and the result indicate a heating demand of 185 000 kWh per year due to thermal transmittance, transmission losses, heating of warm water and a cooling requirement of 5500 kWh.Three different systems of geothermal heating and cooling were tested in the computer program Energy Earth Design. The results show no difference in the dimensioning of the drill hole if merely heating were to be used or both heating and cooling were to be established.

The purpose of this of this essay is to explore the construction of a conservatory that is livable allyear around. When you build a conservatory there are several factors that need to be regardedthat usually are of no importance when you build a regular conservatory. The glassed facadeneeds to have a very good U-value and all the parts of the facade need to be isolated and theconstruction needs to prevent thermal bridges.In this essay we will start by looking at the shape of the conservatory. Due to the façade consistsof glass the conservatory will need to have a good ratio between the area and the façade so thatthe heat losses will be at a minimum. However, due to the fact that one of the sides of the façadeis connected to the warm house, you quickly realize that the shape of the conservatory is of noimportance.There are two common ways to build a foundation for a conservatory, a molded concretefoundation and isolated wooden beams.

This thesis work resulted in a template for how the thermal spray process can be controlled through robot programs. The robots today and their programs need to be replaced, therefore a new structure which can be matched with the new robot systems is needed. The work is limited to only concern structured programming on the new robots on Thermal Spray Centre (TC) with the programming language Rapid. The basic data for the program was retrieved from interviews with concerned personnel at TC, from studies on process parameters for thermal spray and from existing specifications at Volvo Aero Corporation (VAC). The thesis work briefly describes the process thermal spray and the four methods used at VAC.

This report is made as a literature review, focusing on the work done to increase understanding of efficiency in the categories of substations and secondary heating systems, with respect to the deviation from the theoretically possible cooling off in the distribution network as well as the economic benefit that appear. The main purpose of a considerable part of the literature used in this report addresses the issue of identifying individual causes of reduced cooling in district heating systems. These literature resources have been compiled and summarized as part of the report.The technology of district heating is associated with benefits such as better use of the energy in a fuel. This is the case of cogeneration plants where serial generation of electricity and thermal energy increases efficiency compared with the parallel generation where heat is generated locally and electricity is generated centrally. Serial generation thus allows for lower primary energy demand.

Vattenfall district Heating power plant in Uppsala produces district cooling with absorption heat pumps which leads to a large amount of waste heat that has to be cooled with evaporative cooling towers. The Environmental Court has ordered Vattenfall to survey the possibilities to recover the heat, which is the focus of this thesis.The study begins with an overview of the system, and conditions and limitations for waste heat recovery is examined. In the next step alternatives to recycle the heat is evaluated, either by direct recovering or by upgrading.First, the technical possibility of each alternative is discussed, and then the operation time and the amount of recovered heat is calculated. Those alternatives which are possible are brought further to an economic analysis.The cost of investment for each alternative constitutes the basis for a present value analysis. The results are put together in a table where the total amount of recovered heat is compared with the present value for the different alternatives.

In this thesis proposals for different designs of a borehole thermal energy storage (BTES) have been developed for the building DN-huset in Stockholm, Sweden. To build a BTES results in savings in energy costs by approximately 44 %, i.e. 2 million Swedish crowns annually. Furthermore, a BTES would reduce the annual environmental impact with roughly 75-157 tonnes of CO2 equivalents per year, depending on how the electricity consumption?s environmental impact is estimated.

AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.

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.

Modern technology and fast development of heat pumps, the hunt for savings in energy consumption and the strive for environmentally friendly energy sources, convenience, and financial profit, have made heat pumps a reasonable alternative for the heating of houses.When the heat pump starts it will consume a considerable amount of current, which may result in a short-lived voltage-drop if the power grid is weak compared to the start-up current.The company Fortum Distribution which owns and administrates electrical network is interested in an investigation that deals with heat pumps affect on the quality of electricity.The purpose of this investigation is to study fast electrical fluctuations (flicker) as a result of start-up currents for single as well as multiple heat pumps on the same electrical station and from this evaluate whether there will be any problems installing heat pumps..