This thesis is based on a project "Bifacial Photovoltaic Energy Production Analysis" to build a detailed simulation model system accurately simulate bifacial panel performance under real field radiation conditions and deployment configuration, and to predict its corresponding energy yield. To the author’s up-to-date knowledge, the model system is unpreceded among same type simulation software in complexity, details in consideration, ranges of deployment and parameters. The model system can also be used as a platform for more components and variables to be added on, such as adding on more rows of panel arrays to simulate bifacial solar farm scenario; and adding spectral information for more accurate analysis. The system components’ sub-models were carefully chosen based on a broad literature review in related aspects; especially in sky diffuse radiance, ground reflection, and bifacial solar cells. Built in MATLAB© based on mathematical expressions from above said models, the system consists of 5 bifacial panels and their racking as shading objects and the central panel performance is under investigation and has taken consideration of all possible panel azimuth and elevation combinations. Model simplification and resolution are carefully considered so to achieve a good balance in complexity, computation load and output accuracy. Output reliability is confirmed with other people’s work. Furthermore, the model has been fully checked and peer tested. Outputs under different parameter settings are analysed and discussed. Conclusions and recommended future work are provided at the end of the thesis.

Renewable energy studies are becoming increasingly important as world energy demand rises and current energy sources are increasingly questioned. Solar photovoltaics (PV) are the focus of this study as a renewable industry still in its infancy. This research examines the geography of solar panel installation and manufacturing from 2007 to 2010 in California and New York. California is the larger of the two markets and has implemented more policy support; programs that appear to have increased the pace of installations, reduce the size of the subsidy, and help lower total costs. Similar trends are observable in New York. US based companies are still making solar panels, but foreign competitors, most notably from China and Mexico, are capturing an increasing share of the market.

The Regional Council of Jämtland has a goal to increase the export of renewable energy and with that reduce the total greenhouse gas (GHG) emissions. One of the measures used to reach this goal is to give subsidies and tax reductions for investments in photovoltaics. Photovoltaics are generally perceived as “good for the environment” and give a “good image” to companies. They are marketed as interesting for private persons and farmers from a profitability point of view. Sweden has an electricity mix with average CO2 emissions of 20-30 g/kWh. Compared to other countries in Europe this is very low. The CO2 emissions of photovoltaics during their lifetime are 46 g/kWh according to the International Panel on Climate Change (IPCC). Taking this in consideration it can be concluded that photovoltaics actually increase GHG emissions as they have higher emissions of CO2 than the average in Sweden. When the decision to invest in photovoltaics is made with profitability as a main reason, it is debatable if the subsidies and tax reductions are needed. When the decision to invest in photovoltaics is made with environmental concern as a main reason, the subsidies might be given to other environmental technologies that are better from a climate perspective. Considering this, the push for profitability of photovoltaics can be seen as just another increase in consumption.

The aim of the thesis is to design a method of recycling / reutilization of photovoltaic panels at the end of their service life. In the theoretical part is introduced and described photoelectric effect, history, development, production methods and types of photovoltaic panels. Furthermore, the composition and structure of photovoltaic panels are discussed and the technologies currently used for recycling these panels for maximum energy savings are specified. The experimental part of the work is mainly focused on the development of a prototype device, which can measure the current efficiency of the used photovoltaic panels, based on a comparative method, and quickly determine in the field conditions the future reusability of the solar panel.

The master´s thesis deals with a process called cold kinetic deposition technology. Using this technology, a copper layer was formed on a sample with an aluminium base by high-pressure cold spraying at a pressure of 25 bar. In the experimental part, the influence of corrosion degradation in the salt chamber was assessed at the time cycles of 100 h, 200 h and 300h, where changes in internal and surface resistances before and after corrosion were measured. Subsequently, the analysis of corrosion products was performed, where the extent of corrosion attack was determined using an electron microscope. These methods led to a final evaluation of the boundary limits of the applied coating layer by cold kinetic deposition, after the effect of corrosion. Finally, a theoretical application of this technology was suggested. It was discovered that the sample placed and left in the corrosion chamber for the longest time was the most affected by corrosion. Finally, a theoretical application of cold kinetic deposition was proposed.

The basic cube satellite (CubeSat) is a modern small satellite that has a standard size of about one liter (the 1U CubeSat). Three 1U CubeSats could be stacked to form a 3U CubeSat. Their low-cost, short development time, and ease of deployment make CubeSats popular for space research, geographical information gathering, and communication applications. An antenna is a key part of the CubeSat communication subsystem. Traditionally, antennas used on CubeSats are wrapped-up wire dipole antennas, which are deployed after satellite launch. Another antenna type used on CubeSats is the patch antenna. In addition to their low gain and efficiency, deployable dipole antennas may also fail to deploy on satellite launch. On the other hand, a solid patch antenna will compete for space with solar cells when placed on a CubeSat face, interfering with satellite power generation. Slot antennas are promising alternatives to dipole and patch antennas on CubeSats. When excited, a thin slot aperture etched on a conductive sheet (ground plane) is an efficient bidirectional radiator. This open slot antenna can be backed by a reflector or cavity for unidirectional radiation, and solar cells can be placed in spaces on the ground plane not occupied by the slot. The large surface areas of 3U CubeSats can be exploited for a multifunctional antenna by integrating multiple thin slot radiators, which are backed by a thin cavity on the CubeSat surfaces. Solar cells can then be integrated on the antenna surface. Polarization diversity and frequency diversity improve the overall performance of a communication system. Having a single radiating structure that could provide these diversities is desired. It has been demonstrated that when a probe excites a square cavity with two unequal length crossed-slots, the differential radiation from the two slots combines in the far-field to yield circular polarization. In addition, it has been shown that two equal-length proximal slots, when both fed with a stripline, resonate at a frequency due to their original lengths, and also resonate at a lower frequency due to mutual coupling between the slots, leading to a dual-band operation. The multifunctional antenna designs presented are harmonizations and extensions of these two independent works. In the multifunctional antenna designs presented, multiple slots were etched on a 83 mm x 340 mm two-layer shallow cavity. The slots were laid out on the cavity such when the cavity was excited by a probe at a particular point, the differential radiation from the slots would combine in the far-field to yield Left-Handed Circular Polarization (LHCP). Furthermore, when the cavity was excited by another probe at an opposite point, the slots would produce Right-Handed Circular Polarization (RHCP). In addition, as forethought, these slots were laid out on the cavity such that some slots were close together enough to give Linearly Polarized (LP) dual-band operation when fed with a stripline. This antenna was designed and optimized via computer simulations, fabricated using Printed Circuit Board (PCB) technology, and characterized using a Vector Network Analyzer (VNA) and NSI Far Field Systems.

The diploma thesis deals in the theoretical part with various types of sys-tems for the preparation of hot water and specifies the types of solar sys-tems. In the calculation part, it solves the design of kindergarten heating by a system of heating elements. It also solves two variants of hot water preparation in the hot water tank. The design also includes all the equip-ment needed for the proper functioning of the heating system. The exper-imental part compares flat panel and evacuated tube solar collectors.

<p> Silicon solar cells were produced using inexpensive techniques for obtaining high efficiencies. Large area cells were made with efficiencies greater than 10% (AM1) which were subsequently mounted on a Solar panel for future evaluation. </p> / Thesis / Master of Engineering (MEngr)

Climate change has already had major impacts on our planet. Loss of sea ice, accelerated sea level rise and longer, more intense heat waves, are a few of these. Many scientists believe that a continued climate change will have even more severe impact on our planet. To tackle the climate change, a fast transition towards renewable energy sources is necessary. One of the most promising sources of renewable energy is solar energy. To achieve the goal of making the world more reliable on solar energy, various actors try to improve the technology and the financial basis regarding this way of extracting energy. In this transition, calculations have to be as accurate as possible, in order to benefit from them when installing solar panels. This bachelor thesis intends to create an investment model for solar plants and an optimization of the plant’s size based on net present value. The model is built in Microsoft Excel, and factors such as electricity prices, electricity production/consumption and several others are taken into account. Based on the comparison with a case study and the calculations made by the model, the results suggest a reliable model. On behalf of Herrljunga Elektriska AB, the model is created to help them generate reliable and fast investment calculations, which will hopefully bring value to their business.

In this master thesis, several cooling systems for PV-systems have been looked into by doing a smaller literature review and then a cooling module for a BIPV-panel was built out from the knowledge gathered. The cooling module used a PCM material separated into 12 bags and then placed in a 3x4 shaped pattern fastened to an aluminium plate that in turn was placed on the back of a PV-panel. This was tested in first a pilot test and then tested outdoors on panels with insulation on its back to simulate BIPV-panels. Temperature data from behind the panel was gathered with and without the cooling module and then compared with each other with added ambient temperature. It was found that the PCM cooled down the panels during similar weather conditions where the outside temperature and the amount of clouds where approximately the same, and it was also found that PCM technologies needs to be more optimised in terms of its material use, the amount of material, and its arrangement for it to be used in PV-panels. An economical calculation was made and it was found that it wasn't economically viable as it takes 14 years for the PV-panel with cooling to pay for itself while it takes 13 years for the PV-panel with cooling to pay for itself. These results are then discussed in comparison to other systems and earlier work done. / I denna exjobbsrapport så har ett antal olika kylningssystem till PV-paneler setts igenom genom en mindre litteraturstudie. Därefter byggdes en kylningsmodul för en BIPV utifrån den kunskapen som samlats in. Kylningsmodulen använde sig utav ett PCM material som var uppdelat mellan 12 påsar som placerades i ett 3x4 mönster som fästs på baksidan av en aluminiumplåt som i sin tur placerades på baksidan utav PV-panelen. Denna testades först i ett pilottest och sedan utomhus på paneler som isoleras baktill för att simulera BIPV-paneler. Temperaturdata samlades in från panelens baksida, med och utan kylnings modul, som sedan jämfördes med varandra samt omgivningens temperatur. Slutsatsen är att PCM kyler panelen under liknande väderförhållanden där ute temperaturen och molnigheten var ungefär densamma, men att PCM behöver optimeras mer i form av användningen av materialet, mängden av material, och hur det sätts upp som kylning på PV-paneler. En ekonomisk kalkyl genomfördes som visar att det inte är ekonomiskt gångbart eftersom det tar 14 för PV-panelen med kylning att betala av sig själv medan det tar 13 år för PV-panelen utan kylning att göra det. Dessa resultat diskuteras sedan i jämförelse med andra system och tidigare arbeten som gjorts inom området.