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Dissertations / Theses on the topic 'Solar power'
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1
Wang, Zheng. "Solar Power Forecasting." Thesis, The University of Sydney, 2019. https://hdl.handle.net/2123/21248.
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Solar energy is a promising environmentally-friendly energy source. Yet its variability affects negatively the large-scale integration into the electricity grid and therefore accurate forecasting of the power generated by PV systems is needed. The objective of this thesis is to explore the possibility of using machine learning methods to accurately predict solar power. We first explored the potential of instance-based methods and proposed two new methods: the data source weighted nearest neighbour (DWkNN) and the extended Pattern Sequence Forecasting (PSF) algorithms. DWkNN uses multiple data sources and considers their importance by learning the best weights based on previous data. PSF1 and PSF2 extended the standard PSF algorithm deal with data from multiple related time series. Then, we proposed two clustering-based methods for PV power prediction: direct and pair patterns. We used clustering to partition the days into groups with similar weather characteristics and then created a separate PV power prediction model for each group. The direct clustering groups the days based on their weather profiles, while the pair patterns consider the weather type transition between two consecutive days. We also investigated ensemble methods and proposed static and dynamic ensembles of neural networks. We first proposed three strategies for creating static ensembles based on random example and feature sampling, as well as four strategies for creating dynamic ensembles by adaptively updating the weights of the ensemble members based on past performance. We then explored the use of meta-learning to further improve the performance of the dynamic ensembles. The methods proposed in this thesis can be used by PV plant and electricity market operators for decision making, improving the utilisation of the generated PV power, planning maintenance and also facilitating the large-scale integration of PV power in the electricity grid.
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Bennich, Amelie, Johanna Koch, Agnes Kristoffersson, and Carolina Norberg. "Solar Power at Bobygget." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-295107.
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During the autumn of 2014 a project called Bobygget was initiated. The purpose of the project is to establish a future residential area in Herrljunga, where a sustainable and environmentally compatible lifestyle is fundamental. The purpose with this bachelor thesis was to, in consultation with Herrljunga Elektriska, investigate to what extent Bobygget could be self-sufficient from solar energy. Through PV systems at rooftops connected to a shared battery, a given ratio between produced energy and consumption in the area could be acquired. Calculations and simulations resulted in the required amount of bought energy for Bobygget as well as the potential sold energy to the grid. On account of a limited budget, this report was based on three different scenarios with different economic presumptions. The economic presumption for each scenario determined the capacity of the battery, which had an impact on the grade of yearly self-sufficiency. The first scenario resulted in a battery capacity of 63.2 kWh which gave a self-sufficiency of 27 %. In the second scenario the battery had a capacity of 328 kWh which resulted in a self-sufficiency of 50 %. Since the third scenario had an unlimited budget, the capacity of the battery was determined by 100 % utilization of the produced energy. Therefore the battery acquired a capacity of 58 000 kWh which gave a self-sufficiency of 79 %. Consequently, Bobygget could not be completely self-sufficient by installing PV systems at rooftops regardless of budget and capacity of the battery. To be able to accomplish a self-sufficiency of 100 % an alternative solution is necessary.
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Contino, Alessandro Patrizio. "Solar mirrors characterization for concentrating solar power technology." Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/993.
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The increasing availability on the market of different types of solar reflectors such as: polymeric film mirrors, aluminum mirrors and thin glass mirrors, together with: the lack of available norms in this area, and a valid methodology to compare the performances of the candidate reflectors; highlights the necessity to conduct a more detailed analysis on these new technologies.
The objective of the present work is to suggest a valuable method to compare the reflectance performance of mirrors, evaluating also their performances in order to assess:
- the most durable to ageing and weathering effects;
- the different reflectance behavior with the variation of the solar incident angle.
.For these reasons the work here proposed was carried out with an experimental apparatus composed by:
- An Agilent Cary 5000 UV/Vis/NIR spectrophotometer to test the different performance of the mirrors at different characterization steps;
- An integrating sphere of 150 mm in diameter (DRA ¡V Diffuse Reflectance Accessory);
- A VASRA (Variable Angle Specular Reflection Accessory);
- A UV chamber to accelerate the ageing process;
- A £gScan SMS Scatterometer for RMS Roughness and BDSF measurement;
- An outdoor bench
The work was completed with two modeling tools:
- An engineering equation solver (Mathcad) to dynamically evaluate the behavior;
- A ray tracing software (Soltrace) to evaluate the system¡¦s optical efficiency.
The analysis indicates that the candidate reflectors can be accurately characterized with five fundamental parameters:
a) £lSWH, the solar-weighted hemispherical reflectance;
b) £lSWS, the solar-weighted specular reflectance;
c) £lSWS( á), the solar weighted specular reflectance function of the variable angle of incidence;
d) BDSF, Bi Directional Scattering Function;
e) RMS Roughness
This evaluation will provide a valuable tool, for the companies who want to invest in concentrating solar power technology, to decide whether or not using a candidate reflectors to realize new plants, assessing their performances, their costs, and their durability.
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Codd, Daniel Shawn. "Concentrated solar power on demand." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/67579.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 207-215).
This thesis describes a new concentrating solar power central receiver system with integral thermal storage. Hillside mounted heliostats direct sunlight into a volumetric absorption molten salt pool, which also functions as a single tank assisted thermocline storage system. Concentrated light penetrates the molten salt and is absorbed over a depth of several meters; the molten salt free surface tolerates high irradiance levels, yet remains insensitive to the passage of clouds. Thermal losses to the environment are reduced with a refractory-lined domed roof and a small, closeable aperture. The molten salt and cover provide high and low temperature heat sources that can be optimally used to maximize energy production throughout the day, even when the sun is not shining. Hot salt is extracted from the upper region of the tank and sent through a steam generator, then returned to the bottom of the tank. An insulated barrier plate is positioned vertically within the tank to enhance the natural thermocline which forms and maintain hot and cold salt volumes required for operation. As a result, continuous, high temperature heat extraction is possible even as the average temperature of the salt is declining. Experimental results are presented for sodium-potassium nitrate salt volumetric receivers optically heated with a 10.5 kilowatt, 60-sun solar simulator. Designs, construction details and performance models used to estimate efficiency are presented for megawatt-scale molten salt volumetric receivers capable of operating with low cost nitrate or chloride salt eutectics at temperatures approaching 600 'C and 1000 'C, respectively. The integral storage capabilities of the receiver can be sized according to local needs, thereby enabling power generation on demand.
by Daniel Shawn Codd.
Ph.D.
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Rabbani, Michael, and Michael Rabbani. "Zero-Emissions Solar Power Plant." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/625125.
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With energy demand continuously increasing in the United States, renewable energy development is critical to combatting the effects of global climate change. The objective of the project was to create a design for a zero-emissions solar plant. The project group designed a plant to provide electricity to all of residential Chandler, a city with about 100,000 homes. An estimated 543,880 metric tons of carbon dioxide equivalent is produced to power residential Chandler. In contrast, the proposed solar plant will produce zero emissions. Unfortunately, the proposed process is not currently economically feasible.
The proposed process is a concentrating solar power (CSP) tower plant. A central receiver on top of a 175 meter tower absorbs heat reflected off of a field of reflective heliostats. A chloride molten salt mixture flows to the receiver where it is heated to approximately 1000°C. The heated molten salt flows back into a tank where it can be stored for later use or pumped directly to a series of heat exchangers. The working fluid, supercritical carbon dioxide (s-CO2), gains heat from the heat exchanger and powers highly efficient turbines. Waste heat is recovered from the turbines using the closed-loop Brayton Cycle and the s- CO2 is recompressed.
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Dorn, Lawrence Tyrone. "NPS-SCAT electrical power system." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Sep/09Sep_Dorn.pdf.
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Thesis (M.S. in Space Systems Operations)--Naval Postgraduate School, September 2009.Thesis Advisor(s): Newman, James H. "September 2009." Description based on title screen as viewed on November 5, 2009. Author(s) subject terms: Satellite, CubeSat, NPS-SCAT, solar cell tester, Power system, Clyde Space, Spectrolabs, improved triple junction, solar power. Includes bibliographical references (p. 83-85). Also available in print.
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Busch, Brian C. "Space-based solar power system architecture." Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/27802.
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Fossil fuels are, by their very nature, finite resources. There are, however, numerous renewable energy sources that should be taken advantage of. One of the most abundant is also the most difficult to produce on Earthsolar energy. This thesis explores the feasibility of a space-based solar power satellite. The thesis focuses specifically on the satellite design as opposed to the end-to-end design to include the ground segment. It explores the potential orbits for such a satellite to operate from and ultimately concludes that a geostationary orbit is the only logical location for an operational orbit. This thesis also focuses on two segments of the spacecraft the solar array and the power transmission payload. The solar array area was calculated using the current best theoretical solar cells and assumed a 1 GW transmission power. Finally, this thesis explored which transmission payload to recommend for an operational system, concluding that a laser system is the most efficient use of space and weight. The final portion of this thesis was to examine the business case. Based on the design in this thesis, space-based solar power cannot compete with fossil fuels and likely will not for the foreseeable future.
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Collins, Patrick. "Economics of satellite solar power stations." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37665.
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Sheu, Elysia J. (Elysia Ja-Zeng). "Hybrid solar-fossil fuel power generation." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/78189.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 83-92).
In this thesis, a literature review of hybrid solar-fossil fuel power generation is first given with an emphasis on system integration and evaluation. Hybrid systems are defined as those which use solar energy and fuel simultaneously, thus excluding the viable alternative of solar thermal plants which use fossil fuels as backup. The review is divided into three main sections: performance metrics, the different concentrated solar receiver technologies and their operating conditions, and the different hybridization schemes. In addition, a new linear combination metric for analysis of hybrid systems, which considers trade-off of different metrics at the fleet level, is presented. This metric is also compared to alternative metrics from multi-objective optimization. Some previous work only evaluates the hybrid cycle at a certain point in time, which can be misleading as this evaluation would not take into account certain aspects of hybrid cycle such as fluctuating solar supply. Furthermore, almost all previous work designs the hybrid solar-fossil fuel systems for a certain point in time and then evaluates the performance of the system for an entire year. By not taking into account fluctuating solar supply and selling price of electricity in the design of the system, the best possible annual performance of the hybrid cycle may not be reached. Second, an analysis of solar reforming as the integration method for the hybrid cycle is presented, in particular steam reforming of methane. Two solar reforming systems are analyzed: one with a parabolic trough and the other with a solar tower. From the analysis, it is determined that parabolic troughs are not suitable for steam reforming due to the relatively low operating temperatures. The tower reformer system is integrated with a standard combined cycle, and the design and operation of the hybrid cycle is optimized for highest work output for a fixed fuel input and solar collector area (essentially optimizing for maximum cycle efficiency). A heuristic two step procedure is used for the optimization due to the limitation of the optimizer which cannot simultaneously optimize both design and operation. From the optimization, it is determined that the tower reforming integration method is a promising integration option in that this type of hybrid cycle yields high incremental solar efficiencies and also satisfies the linear combination metric for efficiency and CO₂ emissions (i.e., the analyzed hybrid cycle has a higher efficiency for a fixed CO₂ emissions compared to a linear combination of solar only and fossil fuel only cycles).
by Elysia J. Sheu.
S.M.
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Pretorius, Johannes Petrus. "Solar Tower Power Plant Performance Characteristics." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16413.
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Thesis (MScIng)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: This study investigates energy generation by large-scale solar tower power plants. The performance characteristics of a so-called reference plant with a 4000 m diameter glass collector roof and a 1500 m high, 160 m diameter tower are determined for a site located in South Africa. The relevant draught and conservation equations are derived, discretized and implemented in a numerical model which solves the equations using speci ed meteorological input data and determines the power delivered by the plant. The power output of a solar tower power plant over a twenty-four hour period is presented. Corresponding temperature distributions in the ground under the collector are shown. Variations in seasonal generation are evaluated and the total annual electrical output is determined. The dependency of the power output on collector diameter and tower height is illustrated, while showing that greater power production can be facilitated by optimizing the roof shape and height. The minor in uence of the tower shadow falling across the collector is evaluated, while the e ect of prevailing winds on the power generated is found to be signi cant.
AFRIKAANSE OPSOMMING: Hierdie studie ondersoek elektrisiteitsopwekking deur grootskaalse sontoringkragstasies. Die uitsetkarakteristieke van 'n sogenaamde verwysings-kragstasie met 'n 4000 m deursnee glas kollektor en 'n 1500 m hoë, 160 m deursnee toring word ondersoek vir 'n spesi eke ligging in Suid-Afrika. Die toepaslike trek- en behoudsvergelykings word afgelei, gediskretiseer en geimplementeer in 'n numeriese rekenaarmodel. Die rekenaarmodel los die betrokke vergelykings op deur gebruik te maak van gespesi seerde meteorologiese invoerdata en bepaal dan die uitset gelewer deur die kragstasie. Die uitset van 'n sontoring-kragstasie oor 'n periode van vier-en-twintig uur word getoon. Ooreenstemmende temperatuurverdelings in die grond onder die kollektor word geïllustreer. Die variasie in seisoenale elektrisiteitsopwekking word ondersoek en die totale jaarlikse elektriese uitset bepaal. Die invloed wat die kragstasie dimensies (kollektor deursnee en toring hoogte) op die uitset het, word bestudeer en resultate getoon. Daar is ook bevind dat verhoogde uitset meegebring kan word deur die vorm en hoogte van die kollektordak te optimeer. Die geringe e ek van die toringskadu op die kollektor word bespreek, terwyl bevind is dat heersende winde 'n beduidende e ek op die kragstasie uitset het.
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Banyamin, Ziad. "Novel photovoltaic solar power generating diode." Thesis, Manchester Metropolitan University, 2014. http://e-space.mmu.ac.uk/550063/.
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Thin film solar cells are based on semiconductor materials which are configured together to form a single p-n junction. The p-n junction diode is effectively a simple device that has the capacity to absorb part of the sunlight spectrum and deliver the absorbed photon energy to carriers of electrical current known as electrons and holes. A simple p-n junction solar cell device consists of a p-n junction, a metallic grid and a back contact. The aim of this project was to develop and fabricate a p-n heterojunction diode that is robust, developed with low cost and suitable for large surface area. The device attains a heterojunction configuration, consisting of two thin films, each exhibiting different semiconducting behaviour, namely n-type and p-type semiconductors that are brought together to form a p-n junction diode device. The initial stage of this research was to make and characterise a range of oxide coating compositions that can be sputtered from blends of loosely packed powder targets, using the pulsed DC magnetron sputtering technique. These compositions include fluorine doped tin oxide, antimony doped tin oxide and titanium oxide. The different coatings should be transparent conductive oxides (TCO) that exhibit an n-type semiconductor material characteristic. The second objective was to characterise and develop a p-type semiconductor namely copper aluminium oxide to investigate the optimum compositional ratio and the effect of deposition power on the structure of the thin films. The thin films were characterised in terms of their structural, morphological, optical (transmission and band-gap) and electrical (resistivity, mobility and carrier concentration) conditions. The collection of the charge carriers generated from the incident light was achieved through metal ohmic contacts. This was deposited onto both sides of the device using copper and the silver grids/contacts that are deposited onto the n-type layer and the p-type layers, respectively. The design layout of the grid was optimised in order to increase the device efficiency. The final part of this project was to construct the p-n junction device, test the electrical (current-voltage characteristics) performance and investigate the rectifying behaviour and the formation of the p-n junction.
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Золотова, Світлана Григорівна, Светлана Григорьевна Золотова, Svitlana Hryhorivna Zolotova, and D. S. Volovik. "Solar Power in Reducing Carbon Footprint." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/13461.
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Bailey, Nicolas. "Reliability evaluation of solar power in South Africa's power system." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/9135.
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Includes bibliographical references.Global utilisation of renewable energy sources such as solar photovoltaics (PV) in electric power systems is growing rapidly due to government incentives, and negative environmental impacts associated with conventional generators. Many consider solar PV as a promising alternative source of energy due to its apparent environmental, social and economic benefits. This together with government incentives and programmes such as the renewable energy independent power procurement program (REIPPPP) has allowed for investment in PV in South Africa (SA). Solar irradiation is a variable energy source and thus serious consideration needs to be given to the effect that PV might have on the reliability of the system. As a result traditional methods of evaluating power system reliability cannot be used when utility-scale PV is introduced to the system. Thus probabilistic methods are commonly employed to evaluate reliability. In this thesis time series data was used to simulate the yield from 27 PV plants, as defined by round 1 and round 2 of the REIPPP process, through a yield model developed for this investigation.
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Pierce, Warrick Tait. "Solar assisted power generation (SAPG) : investigation of solar preheating of feedwater." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80139.
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Thesis (MEng)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Solar Assisted Power Generation (SAPG) can be seen as a synergy of solar and fossil plants – combining the environmental benefits of the former and the scale, efficiency and reliability of the latter. SAPG offers great potential for cost effective utilization of solar energy on utility scale and could accelerate the adoption of solar thermal energy technologies in the short and medium term, especially in countries with a significant coal base and a good solar resource such as Australia, China, United States, India and South Africa. SAPG is the replacement of bled-off steam in a Regenerative Rankine power cycle. Power plant simulations were performed using weather data for Lephalale, South Africa (Matimba power station). With an increase in the solar field outlet temperature, an increase in overall solar to electric efficiency was observed, superior to a stand-alone Solar Thermal Power Plant(s) (STPP) at similar temperatures. The performance of four solar collector technologies was compared: flat plate, evacuated tube, Linear Fresnel (LF) and Parabolic Trough (PT). This comparison was limited to the normal incidence angles of irradiation. For this application, nonconcentrating technologies are not competitive. For non-normal incidence angles, annual simulations were limited to PT and LF at final feedwater heater temperatures. The actual aperture area of around 80 000 m2 was used (50 MW thermal based on LF). On an equal aperture area basis, PT outperforms LF significantly. For the conventional North-South arrangement, LF needs to be around 53% of the specific installation cost (in $/m2 aperture area) of PT to be cost competitive. A SAPG plant at Lephalale was compared to a stand-alone Solar Thermal Power Plant STPP in a good solar resource area, namely Upington, South Africa – Parabolic Trough solar collector fields of equal size were considered for both configurations. It was found that the annual electricity generated with a SAPG plant is more than 25% greater than a stand-alone STPP. If the cost of SAPG is taken as 72% of the cost of a stand-alone STPP, this translates into SAPG being 1.8 times more cost effective than stand-alone STPP. Furthermore, SAPG performs better in high electricity demand months (South African winter – May to August). Stand-alone STPP have been adopted in South Africa and are currently being built. This was achieved by the government creating an attractive environment for Independent Power Producers (IPP). Eskom, the national power supplier, is currently investigating solar boosting at existing Eskom sites. This report argues that on a national level, SAPG, specifically solar preheating of feedwater, is a more viable solution for South Africa, with both its significant coal base and good solar resource.
AFRIKAANSE OPSOMMING: Son ondersteunde krag generasie (SOKG) kan gesien word as sinergie van sonkrag en fossiele brandstof aanlegte – dit voeg die omgewings voordele van die eersgenoemde en die grote, effektiwiteit en betroubaarheid van die laasgenoemde by mekaar. SOKG opper groot potensiaal vir koste effektiewe gebruik van son energie op nutsmaatskappyskaal en kan die aanvaarding van sontermiese energietegnologieë in die kort en medium termyn versnel, veral in lande met beduidende kool reserwes en goeie sonkrag voorkoms soos Australië, China, Verenigde State van Amerika, Indië en Suid-Afrika. SOKG impliseer die vervanging van aftap stoom in die regeneratiewe Rankine krag kringloop. Kragstasie simulasies was gedoen met die gebruik van weer data van Lephalale, Suid-Afrika (Matimba kragstasie). Met die toename van die sonveld uitlaat temperatuur kon oorhoofse son-na-elektrisiteit effektiwiteit vasgestel word, wat hoër is as die van alleenstaande sontermiese krag stasie (STKS) by soortgelyke temperature. Die effektiwiteit van vier son kollekteerder tegnologieë was vergelyk: plat plaat, vakuum buis, lineêre Fresnel (LF) en paraboliese trog (PT). Die vergelyking was beperk tot normale inval van bestraling. Vir hierdie toepassing is nie-konsentreerende tegnologie nie mededingend nie. Vir nie-normale inval hoeke was jaarlange simulasies beperk tot PT en LF by finale voedingswater temperatuur. Die werklike opening area van omtrent 80 000 m2 was gebruik (50 MW termies gebaseer op LF). By gelyke opening area, uitpresteer PT LF beduidend. Vir die gebruiklike Noord-Suid rankskikking benodig LF omtrent 53% van die spesifieke installasie kostes (in $/m2 opening area) van PT om kostes mededingend te kan wees. ‘n SOKG aanleg by Lephalale was vergelyk met alleenstaande STKS in die goeie son voorkoms gebied van Upington, Suid-Afrika – Paraboliese trog kollekteerder velde van gelyke grote was oorweeg vir al twee konfigurasies. Dit was gevind dat die jaarlikse elektrisiteit gegenereer vanaf SOKG meer as 25% is as die van alleenstaande STKS. Indien SOKG oorweeg word met 72% van die kostes van alleenstaande STKS, dan beteken dit dat SOKG 1.8 keer meer koste effektief is as alleenstade STKS. Verder, SOKG presteer beter in die hoer elektrisiteitsnavraag maande (Suid- Afrikaanse winter – May tot Augustus). Alleenstaande STKS is gekies vir Suid-Afrika en word tans gebou. Dit is bereik deur dat die regering ‘n aantreklike omgewing geskep het vir onafhanglike krag produsente. Eskom ondersoek tans SOKG by bestaande Eskom persele. Hierdie verslag beweer dat op nasionale/Eskom vlak, SOKG, besonders son voorverhitting van voedingswater, meer haalbare oplossing is vir Suid-Afrika met sy beduidende koolreserwes en goeie son voorkoms.
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Avapak, Sukunta. "Failure mode analysis on concentrated solar power (CSP) plants : a case study on solar tower power plant." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/102375/1/Sukunta_Avapak_Thesis.pdf.
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This thesis is an investigation of critical failure modes of solar tower power system in concentrated solar power (CSP) technology. The thesis evaluated the causes and impacts of failure on the major components and apply the failure Mode and Effect Analysis (FMEA) to CSP solar tower system. This research proposed an alternative method to overcome the limitations of Risk Priority Number (RPN) from traditional FMEA. A case study applies the proposed approach to CSP solar tower system for a better prioritization of failure mode in order to reduce the risk of failures.
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Jain, Chinmay. "Design, control and implementation of grid tied solar energy conversion systems." Thesis, IIT Delhi, 2017. http://localhost:8080/xmlui/handle/12345678/7058.
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Guoan, Christopher M. "Ground-based high energy power beaming in support of spacecraft power requirements." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Jun%5FGuoan.pdf.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 2006.Thesis Advisor(s): Sherif Michaels. "June 2006." Includes bibliographical references (p. 119-124). Also available in print.
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Li, Yiyang. "Novel power converter topologies to interface solar power to power grid with battery backup." Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/23269.
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The main aim of this thesis is to develop a solar energy system for domestic utilities, using a bi-directional DC-DC boost converter with a battery storage system in it. Topologies of the converters employed in the existing system are not efficient, especially in high power applications because of complicated structures with many power devices. In order to step up the DC voltage of the solar panel to a value suitable for AC power conversion, the DC-DC converter topologies has used either multiple stages of voltage amplification or complicated structures with many power devices as the voltage gain offered by the standard boost converter is not adequate enough. This has led to the use of complicated switching control methods. As a result of such power converters with low power density, the cost of the system is also high with relatively low efficiency. The above-mentioned shortcomings have led researchers to investigate new topologies of converters and efficient control methods. The thesis investigates the existing topologies of DC-DC boost converters pointing out advantages and disadvantages and presents ten new topologies that are superior to existing ones. Detailed analysis of converters is presented, and the mathematical model is developed to determine the voltage gain as a function of duty cycle. The presented converter topologies are also designed, and prototypes fabricated in the laboratory. The fabricated converters are tested experimentally using Arduino micro-controller. Programs are developed to control the converters in different modes of operation and the performance curves are generated. The experimental results support the theoretical model developed and the obtained results are presented in the thesis. A bi-directional DC-AC converter topology is also developed to interface the solar panel to the AC grid. The developed topology makes use of one of the DC-DC converter topologies presented and offers battery backup facility in it. This system can be controlled to store power either from AC grid or from the solar panel and can power the AC load or inject power to the grid. Appropriate control methods are developed for the bi-directional converter system and extensive simulation studies are conducted using MATLAB/Simulink to demonstrate the operation of the system in different modes of operation and simulation results are also presented. The converter system has also been fabricated and tested with solar panels. The test results of different modes of operation are also presented. Finally, the authors’ viewpoint in the development of power electronics in solar application is presented.
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Trolove, Hamish P. "Line focus solar Stirling domestic power generation." Thesis, University of Canterbury. Mechanical Engineering, 1994. http://hdl.handle.net/10092/6468.
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This thesis has found that to generate electricity for a domestic supply, the use of a two stage line focus concentrator coupled to a Stirling engine by way of a heat pipe is very inefficient, and the end result (useful power) could be better achieved by a line focus system with a Rankine cycle heat engine, or by using photovoltaic cells. For larger systems such as that needed to supply a small community, a point focus solar Stirling engine is the most efficient system at this stage, but with the rapid improvements being made in the performance of photovoltaic cells, this may not be the case in the future.
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Sityar, Irma. "Sun sensor implementation using solar power arrays." Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/24058.
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Amatya, Reja. "Solar thermoelectrics for small scale power generation." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70784.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 243-253).
In the past two decades, there has been a surge in the research of new thermoelectric (TE) materials, driven party by the need for clean and sustainable power generation technology. Utilizing the Seebeck effect, the thermoelectric devices can be used as heat engines to convert heat into electricity. With no moving parts, the generators are considered highly reliable with low maintenance, which is essential for decentralized power source. With nearly 1.6 billion people living without basic electricity, the need for a small scale power generation is there. Through this work, we show that the solar thermoelectric generators (STEGs) using cheap parabolic concentrators with high ZT modules can be a viable and a costeffective alternative to solar photovoltaics for distributed power generation. The maximum conversion efficiency of 3% has been achieved for a STEG under AM 1.5G conditions with commodity thermoelectric module. The generator was able to produce a peak output power of 11 W, with an inexpensive parabolic solar concentrator which can be found in developing countries being used as solar cookers. The output power is the highest achieved value for concentrated solar thermoelectrics and it is comparable to photovoltaic modules that are deployed in these rural communities. Based on a heat transfer model developed during this work, various system parameters were analyzed for maximizing the performance. An optimized thermoelectric module design with a slight aspect ratio variation for the TE legs have been identified that can increase the efficiency by 28%. Another parameter for system improvement that has been considered is the use of novel TE material. Issues of earth-abundance, material scarcity and cost have been taken into consideration for new material. These are important considerations for a technology that can have a potential cost-effective large scale deployment. A robust, high temperature thermoelectric material characterization tool (Z-meter) has been developed with proper radiation suppression (20x below black body radiation) and low system parasitics (41.6% lower electrical contact parasitic that previous published results). We investigated novel metalsemiconductor superlattice structures ((HfZr)N/ScN) using the Z-meter setup. Low thermal conductivities (2.5-5 W/m.K) have been measured for temperature range of 300-650 K. The Seebeck coefficient of 132 [mu]V/K was measured at 830 K, which is comparable to the state-of-the-art SiGe at similar temperature.
by Reja Amatya.
Ph.D.
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Kamanzi, Janvier. "Thermal electric solar power conversion panel development." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2527.
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Thesis (DTech (Engineering))--Cape Peninsula University of Technology, 2017.The world has been experiencing energy-related problems following pressuring energy demands which go along with the global economy growth. These problems can be phrased in three paradoxical statements: Firstly, in spite of a massive and costless solar energy, global unprecedented energy crisis has prevailed, resulting in skyrocketing costs. Secondly, though the sun releases a clean energy, yet conventional plants are mainly being run on unclean energy sources despite their part in the climate changes and global warming. Thirdly, while a negligible percentage of the solar energy is used for power generation purposes, it is not optimally exploited since more than its half is wasted in the form of heat which contributes to lowering efficiency of solar cells and causes their premature degradation and anticipated ageing. The research is geared at addressing the issue related to unsatisfactory efficiencies and anticipated ageing of solar modules. The methodology adopted to achieve the research aim consisted of a literature survey which in turn inspired the devising of a high-efficiency novel thermal electric solar power panel. Through an in-depth overview, the literature survey outlined the rationale of the research interest, factors affecting the performance of PVs as well as existing strategies towards addressing spotted shortcomings. While photovoltaic (PV) panels could be identified as the most reliable platform for sunlight-to-electricity conversion, they exhibit a shortcoming in terms of following the sun so as to maximize exposure to sunlight which negatively affects PVs’ efficiencies in one hand. On the other hand, the inability of solar cells to reflect the unusable heat energy present in the sunlight poses as a lifespan threat. Strategies and techniques in place to track the sun and keep PVs in nominal operational temperatures were therefore reviewed.
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Isaksson, Emil, and Conde Mikael Karpe. "Solar Power Forecasting with Machine Learning Techniques." Thesis, KTH, Matematisk statistik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229065.
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The increased competitiveness of solar PV panels as a renewable energy source has increased the number of PV panel installations in recent years. In the meantime, higher availability of data and computational power have enabled machine learning algorithms to perform improved predictions. As the need to predict solar PV energy output is essential for many actors in the energy industry, machine learning and time series models can be employed towards this end. In this study, a comparison of different machine learning techniques and time series models is performed across five different sites in Sweden. We find that employing time series models is a complicated procedure due to the non-stationary energy time series. In contrast, machine learning techniques were more straightforward to implement. In particular, we find that the Artificial Neural Networks and Gradient Boosting Regression Trees perform best on average across all sites.Sänkta produktionskostnader och ökad effektivitet har de senaste åren gjort solceller till ett attraktivt alternativ som energikälla. Detta har lett till en stor ökning av dess användning runt om i världen. Parallellt med denna utveckling har större tillgänglighet av data samt datorers förbättrade beräkningskapacitet möjliggjort förbättrade prediktionsresultat för maskininlärningsmetoder. Det finns för många aktörer anledning att intressera sig för prediktion av solcellers energiproduktion och från denna utgångspunkt kan maskininlärningsmetoder samt tidsserieanalys användas. I denna studie jämför vi hur metoder från de båda fälten presterar på fem olika geografiska områden i Sverige. Vi finner att tidsseriemodeller är komplicerade att implementera på grund av solcellernas icke-stationära tidsserier. I kontrast till detta visar sig maskininlärningstekniker enklare att implementera. Specifikt finner vi att artificiella neurala nätverk och så kallade Gradient Boosting Regression Trees presterar bäst i genomsnitt över de olika geografiska områdena.
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Опанасюк, Анатолій Сергійович, Анатолий Сергеевич Опанасюк, Anatolii Serhiiovych Opanasiuk, Таїсія Олександрівна Бересток, Таисия Александровна Бересток, and Taisiia Oleksandrivna Berestok. "Research laboratory «optoelectronics and solar power engineering»." Thesis, Одеський національний політехнічний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/34062.
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The main goal of the research is to create a device structures (solar cells, optical detectors, and hard radiation detector gases) based on heterojunctions and semiconductor-metal structures.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34062
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Fredskov, Linus, and Mikael Renardsson. "Costs for Floating Solar Power in Sweden." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-95797.
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År 2016 slöts energiöverenskommelsen av de fem riksdagspartierna Moderaterna, Socialdemokraterna, Miljöpartiet, Centerpartiet och Kristdemokraterna. Denna överenskommelse innebär att Sverige målsäter att år 2040 ha en helt förnybar energiförsörjning. För att uppnå detta krävs det att den svenska energiproduktionen utvecklas och förbättras. Syftet med denna studie är att undersöka huruvida kostnadseffektiviteten hos solenergi i Sverige kan höjas genom att placera solpaneler flytande på vatten i stället för på land. Det har i tidigare studier påvisats att verkningsgraden hos solenergi kan höjas igenom att placera solpaneler flytande ovanför vattenytan och ta fördel av vattnets nedkylande effekt. Denna studie har använts sig av en kvantitativ forskningsmetod. Resultatet påvisade att kostnadseffektiviteten för solenergi i Sverige kan höjas igenom att placera solpanelerna flytande på vatten i stället för på land.In 2016, the energy agreement was signed by the five parliamentary parties Moderaterna, Socialdemokraterna, Miljopartiet, Centerpartiet and Kristdemokraterna. This agreement means that Sweden aims to have a completely renewable energy supply by 2040. To achieve this, it is necessary that the Swedish energy production is developed and improved. The purpose of this study is to investigate whether the cost-effectiveness of solar energy in Sweden can be increased by placing solar panels floating on water instead of on land. Previous studies have shown that the effects of solar energy can be increased by placing solar panels floating above the surface of the water and taking advantage of the cooling effect of the water. In this study a quantitative research method has been used. The result showed that the cost-effectiveness of solar energy in Sweden can be increased by placing solar panels floating at the water surface instead of on land.
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Kanten, Bethany. "Power Monitoring Device for Off-Grid Solar." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:14398556.
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Off-grid solar power systems are being used in rural, developing regions of the world to provide electricity to communities that previously didn’t have access. These systems are unable to communicate data about power generation and consumption to the organizations that install them. This information can be critical for the organization to ensure they are providing quality electricity, maintain the health of the components in their system, and evaluate the impact they are having in the community. I designed and built a device to monitor power at both the generation and AC or DC consumption sites. Once daily it sends the data to a website via text message where is it displayed to the installer. The device also stores the data locally on a microSD card. The final device abides by the key specifications set by the prior art of low cost and low power consumption. The device also addresses key challenges of off-grid monitoring including data transmission via text message, battery monitoring, reliability/ durability, and versatility with load site monitoring.
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Parvareh, Forough. "Solar Repowering of PCC-retrofitted Power Plants." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/15473.
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The integration of concentrated solar thermal technology with PCC-retrofitted power plants has the potential to recover the power plant penalty while capturing carbon through the PCC plant. The main contribution of this thesis is showcasing such synergy between solar and PCC-retrofitted power plants through development of a model investigating the solar plant dynamic behaviour and response to external disturbances including climatic changes for the Australian context. Firstly, the potential of solar thermal and/or power energy to compensate for both PCC penalties is investigated. The mode of integrated solar energy with the PCC-retrofitted power plant and the integration point in the superstructure, result in a number of possible configurations among which, three are shown to have a higher potential to meet the operational objective, maintaining the original output rate while PCC is operating. The basic sizing data, a preliminary size of each configuration, operational capability and complexity level involved in the integration of each configuration are established. A limitation was faced in assessing the performance of each option using levelised cost of energy due to the lack of a dynamic profile of high-pressure side feed water preheaters of the PCC-retrofitted power plant. Additionally, a dynamic study on the superstructure was required using the annual dynamic profile of PCC load requirements, carbon price and power demand. Despite these, this work has shown near optimal values for solar multiple and number of full load hours of thermal storage for each configuration. These results are used to select one option for a dynamic model. A comprehensive dynamic study is performed on Option 2 using TRNSYS modelling package. The main operating and control schemes are identified and details of the modelling are provided followed by an analysis of performance results and conclusion and a note for future directions.
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Chalk, Ryan. "Solar power generation in a mining town." Thesis, Chalk, Ryan (2017) Solar power generation in a mining town. Honours thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/38686/.
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Climate change is a pertinent issue facing governments and societies around the world. The industrial revolution has resulted in a steady increase in the average global temperature. The mining and energy production industries have been significant contributors to this change prompting governments to intervene by promoting low emission technology within these sectors. This thesis reviews the energy problem in Australia and the mining sector with a focus on the energy requirements and production methods utilised in Newman WA. BHP operate the largest open cut iron ore mine in the world requiring substantial amounts of energy to maintain.
Renewable energy in the form of utility scale solar photovoltaics (PV) provides a solution to these problems by providing emission free energy which can be used to supplement the existing natural gas turbines in operation. This research presents a custom renewable solution for the Newman scenario considering the specific township network, local weather conditions and load profile. A summary of the required PV output is presented to supply slightly over 50% of the towns power requirements during the peak (summer) period, resulting in close to full coverage in the trough (winter) period. Power Factory is used to simulate the characteristics of the existing infrastructure and produces results of integrating PV. These results conclude that the problems requiring mitigation strategies unacceptable levels of harmonics and low power factor.
Strategies are proposed to control these issues predominantly through the use of high quality, made for purpose inverters. Results show that use of inverters with harmonic filtering dramatically reduce the level of harmonic injections to an acceptable level according to Australian standards. Furthermore, the configuration of inverters to supply active and reactive power assist in mitigating low power factor problems.
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Cottam, P. J. "Innovation in solar thermal chimney power plants." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10045417/.
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This thesis analyses novel technology for renewable electricity generation: the solar thermal chimney (STC) power plant and the suspended chimney (SC) as a plant component. The STC consists of a solar collector, a tall chimney located at the centre of the collector, and turbines and generators at the base of the chimney. Air heated in the collector rises up the chimney under buoyancy and generates power in the turbines. STCs have the potential to generate large amounts of power, but research is required to improve their economic viability. A state-of-the-art STC model was developed, focussing on accurate simulation of collector thermodynamics, and providing data on flow characteristics and plant performance. It was used to explore power generation for matched component dimensions, where for given chimney heights, a range of chimney and collector radii were investigated. Matched dimensions are driven by the collector thermal components approaching thermal equilibrium. This analysis was complemented with a simple cost model to identify the most cost-effective STC configurations. The collector canopy is an exceptionally large structure. Many of the designs proposed in the literature are either complex to manufacture or limit performance. This thesis presents and analyses a series of novel canopy profiles which are easier to manufacture and can be incorporated with little loss in performance. STC chimneys are exceptionally tall slender structures and supporting their self-weight is difficult. This thesis proposes to re-design the chimney as a fabric structure, held aloft with lighter-than-air gas. The performance of initial, small scale suspended chimney prototypes under lateral loading was investigated experimentally to assess the response to wind loads. A novel method of stiffening is proposed and design of larger prototypes developed. The economic viability of a commercial-scale suspended chimney was investigated, yielding cost reductions compared to conventional chimney designs.
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Hicks, Nathan Andrew. "Solar Power for Deployment in Populated Areas." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/141.
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The thesis presents background on solar thermal energy and addresses the structural challenges associated with the deployment of concentrating solar power fields in urban areas. Two potential structural systems and urban locales of deployment are proposed and investigated to determine whether they have the potential to be a cost-effective renewable energy solution for urban areas. The structural issues explored in the thesis include flutter, the wind loading of open frame structures, performance-based design, and the design of flexibly mounted equipment on a building.
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Miranda, Gilda. "Dispatch Optimizer for Concentrated Solar Power Plants." Thesis, Uppsala universitet, Byggteknik och byggd miljö, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-402436.
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Concentrating solar power (CSP) plant is a promising technology that exploits direct normal irradiation (DNI) from the sun to be converted into thermal energy in the solar field. One of the advantages of CSP technology is the possibility to store thermal energy in thermal energy storage (TES) for later production of electricity. The integration of thermal storage allows the CSP plant to be a dispatchable system which is defined as having a capability to schedule its operation using an innovative dispatch planning tool. Considering weather forecast and electricity price profile in the market, dispatch planning tool uses an optimization algorithm. It aims to shift the schedule of electricity delivery to the hours with high electricity price. These hours are usually reflected by the high demand periods. The implementation of dispatch optimizer can benefit the CSP plants economically from the received financial revenues. This study proposes an optimization of dispatch planning strategies for the parabolic trough CSP plant under two dispatch approaches: solar driven and storage driven. The performed simulation improves the generation of electricity which reflects to the increase of financial revenue from the electricity sale in both solar and storage driven approaches. Moreover, the optimization also proves to reduce the amount of dumped thermal energy from the solar field.
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Gannon, A. J. "Solar chimney turbine performance /." Link to the online version, 2002. http://hdl.handle.net/10019/1526.
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Bialobrzeski, Robert Wetherill. "Optimization of a SEGS solar field for cost effective power output." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/24631.
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Bame, Aaron T. "Optimization of Solar-Coal Hybridization for Low Solar Augmentation." BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/8942.
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One approach to enabling a larger penetration of renewable sources of energy is the implementation of hybrid power plants. This work presents a process to determine the preliminary optimal configuration of a concentrating solar power-coal hybrid power plant with low solar augmentation, and is demonstrated on a coal power plant in Castle Dale, UT. A representative model is developed and validated against published data for a coal power plant of a different configuration than Hunter Unit 3. The simplifications within the representative model include combining multiple feedwater heaters, combining turbines that operate across the same boundary states, and the mass-average calculation for extraction properties to the combined feedwater heaters. It is shown that the representative model can accurately and consistently simulate a coal power plant. Comparing net power generation and boiler heating estimates from the representative model to the benchmark power plant, the representative model is accurate to within +/- 1% the accepted value from the benchmark power plant. The methods for quantifying solar resource with data from the National Renewable Energy Laboratory are presented with the derivation of an algorithm to simulate a concentrating solar power field arrangement. The solar contribution to electrical power output is estimated using an exergy balance. A simplified financial model is also developed to estimate the solar marginal levelized cost of electricity and payback time using a cash-flow analysis. Estimates for solar resource, solar contribution, and financial performance are consistent with data published by the National Renewable Energy Laboratory or in archival literature. A multi-objective optimization routine is developed consisting of the representative model, the augmentation of solar energy into the solar integration model by means of feedwater heater bypass, solar contribution, levelized cost of electricity, and payback time. Because this study considered complete FWH bypass, higher solar augmentation (>3% of boiler heating) is required for a hybrid design to be considered feasible. However, for higher solar augmentation, the costs are also considerably higher and the financial benefit is insufficient to make any hybrid designs feasible unless a carbon tax is in place. A carbon tax will amplify the financial benefit of hybridization, so optimization results are provided assuming a carbon tax value equivalent to the value used in California's Emissions Trading System (16 USD sh.tn.^-1). The impact of a green energy premium price paid by consumers is also explored in the context of payback time. The resulting optimal design for the Hunter Unit 3 with a carbon tax and no premium is using parabolic trough collector technology at an augment fraction of k=9% to bypass feedwater heater 6. The resulting marginal solar levelized cost of electricity is 9.5 x 10^-4 USD kWh^-1 with an estimated payback time of 25.2 years. This process can be applied to any coal power plant for which operating data and meteorological data are available to evaluate preliminary hybridization feasibility.
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Almquist, Isabelle, Ellen Lindblom, and Alfred Birging. "Workplace Electric Vehicle Solar Smart Charging based on Solar Irradiance Forecasting." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-323319.
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The purpose of this bachelor thesis is to investigate different outcomes of the usage of photovoltaic (PV) power for electric vehicle (EV) charging adjacent to workplaces. In the investigated case, EV charging stations are assumed to be connected to photovoltaic systems as well as the electricity grid. The model used to simulate different scenarios is based on a goal of achieving constant power exchange with the grid by adjusting EV charging to a solar irradiance forecast. The model is implemented in MATLAB. This enables multiple simulations for varying input parameters. Data on solar irradiance are used to simulate the expected PV power generation. Data on driving distances are used to simulate hourly electricity demands of the EVs at the charging stations. A sensitivity analysis, based on PV irradiance that deviates from the forecast, is carried out. The results show what power the grid needs to have installed capacity for if no PV power system is installed. Furthermore, appropriate PV power installation sizes are suggested. The suggestions depend on whether the aim is to achieve 100 percent self-consumption of PV generated power or full PV power coverage of charging demands. For different scenarios, PV power installations appropriate for reducing peak powers on the grid are suggested. The sensitivity analysis highlights deviations caused by interference in solar irradiance.
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Bengtsson, Tobias, and Håkan Hult. "Combining Solar Energy and UPS Systems." Thesis, KTH, Tillämpad termodynamik och kylteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148042.
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Solar Power and Uninterruptible Power Supply (UPS) are two technologies that are growing rapidly. The demand for solar energy is mainly driven by the trend towards cheaper solar cells, making it economically profitable for a larger range of applications. However, solar power has yet to reach grid parity in many geographical areas, which makes ways to reduce the cost of solar power systems important. This thesis investigates the possibility and potential economic synergies of combining solar power with UPS systems, which have been previously researched only from a purely technical point of view. This thesis instead evaluates the hypothesis that a combined solar and UPS system might save additional costs compared to regular grid-tied systems, even in a stable power grid. The primary reason is that on-line UPS systems rectifies and inverts all electricity, which means that solar energy can be delivered to the DC part of the UPS system instead of an AC grid, avoiding the installation of additional inverters in the solar power system. The study is divided into three parts. The first part is a computer simulation using MATLAB, which has an explorative method and aims to simulate a combined system before experimenting physically with it. The second part consists of experiments on a physical prototype system based on basic UPS and solar power components. The third part is an economical assessment of investment costs and energy balances, comparing two separate systems (UPS and solar power separate) to one combined (UPS & solar power). The results from the prototype system show that adding solar power to an UPS system does not interfere with the UPS functionality in any major way, however for optimal performance some additional integration may be necessary. On the contrary, the additional power terminal that the solar panels constitute, can increase system performance during certain operational conditions. The result of the economic analysis shows that a combined system has potential for both a lower investment cost due to cheaper components and increased energy savings through lower conversion losses. The conclusion from the study is that a combined solar energy and UPS system is technically feasible. Furthermore, a combined system has clear economic advantages over two separate systems. This means that a combined system might be economically profitable even in situations where a separate system is not.Solenergi och avbrottsfri kraftförsörjning (UPS) är två tekniker som växer snabbt. Efterfrågan på solenergi ökar huvudsakligen på grund av den snabba utvecklingen mot billigare solceller, vilket lett till att solenergi blivit lönsamt i en större mängd applikationer. I många områden är solenergi dock fortfarande inte kostnadsmässigt konkurrenskraftigt jämfört med traditionella energikällor, vilket gör en fortsatt sänkning av kostnaderna för solenergi till en viktig fråga för solenergiindustrin. Detta examensarbete har som syfte att undersöka om det är tekniskt möjligt att kombinera solenergi med UPS-system samt potentialen för ekonomiska synergier med denna kombination. Tidigare forskning inom området har endast undersökt denna kombination från en rent teknisk synvinkel. Detta examensarbete driver istället hypotesen att ett kombinerat solenergi- och UPS-system kan leda till större kostnadsbesparingar jämfört med ett traditionellt nätanslutet solenergisystem, även i ett stabilt elnät som i Sverige. En on-line UPS skyddar en känslig last genom att kontinuerligt likrikta och sedan åter växelrikta inkommande ström för att därmed både isolera lasten från nätet samt höja strömkvalitén. I UPS-systemet finns därmed en likströmsdel dit solpanelerna direkt kan kopplas istället för att skicka den genererade solenergin ut på elnätet. Därmed undviks inköp och installation av sol-växelriktare i solenergisystemet. Studien är uppdelad i tre delar. Första delen är en datorsimulering i MATLAB och syftar till att explorativt undersöka det kombinerade systemet för en optimerad design innan fysiska experiment utförs. Den andra delen av studien utgörs av experiment på ett fysiskt prototypsystem baserat på ett principiellt UPS- och solenergisystem. Den tredje delen av studien är en ekonomisk analys av både investeringskostnader och energibalanser som jämför ett kombinerat system (UPS & sol) med två separata system (UPS & sol separat). Resultaten från prototypsystemet visar att påkopplandet av solceller i en principiell UPS har mycket låg påverkan på UPS-systemets funktionalitet, samt att solcellerna som en extra energikälla under vissa driftförhållanden kan ha en positiv påverkan på UPS-systemet. För optimal prestanda kan dock en viss integration av systemen krävas. Resultatet från den ekonomiska analysen visar att ett kombinerat system har potential att sänka investeringskostnaden genom billigare komponenter. Ett kombinerat system kan även leda till en högre energibesparing jämfört med ett nätanslutet solenergisystem eftersom konverteringsförlusterna i UPS-systemet sjunker i det kombinerade systemet. Slutsatsen av studierna är att ett kombinerat solenergi- och UPS-system är tekniskt möjligt. Dessutom finns betydande ekonomiska synergier med ett kombinerat system. Detta innebär att ett kombinerat system kan vara lönsamt även i fall där ett separat solelsystem inte är det.
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Howard, Dustin F. "Modeling, simulation, and analysis of grid connected dish-stirling solar power plants." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34832.
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The percentage of renewable energy within the global electric power generation portfolio is expected to increase rapidly over the next few decades due to increasing concerns about climate change, fossil fuel costs, and energy security. Solar thermal energy, also known as concentrating solar power (CSP), is emerging as an important solution to new demands for clean, renewable electricity generation. Dish-Stirling (DS) technology, a form of CSP, is a relatively new player in the renewable energy market, although research in the technology has been ongoing now for nearly thirty years. The first large plant utilizing DS technology, rated at 1.5 MW, came online in January 2010 in Peoria, AZ, and plants rated for several hundred MW are in the planning stages. Increasing capacity of this technology within the utility grid requires extensive dynamic simulation studies to ensure that the power system maintains its safety and reliability in spite of the technological challenges that DS technology presents, particularly related to the intermittency of the energy source and its use of a non-conventional asynchronous generator. The research presented in this thesis attempts to fill in the gaps between the well established research on Stirling engines in the world of thermodynamics and the use of DS systems in electric power system applications, a topic which has received scant attention in publications since the emergence of this technology.
DS technology uses a paraboloidal shaped dish of mirrors to concentrate sunlight to a single point. The high temperatures achieved at the focal point of the mirrors is used as a heat source for the Stirling engine, which is a closed-cycle, external heat engine. Invented by the Scottish clergyman Robert Stirling in 1816, the Stirling engine is capable of high efficiency and releases no emissions, making it highly compatible with concentrated solar energy. The Stirling engine turns a squirrel-cage induction generator, where electricity is delivered through underground cables from thousands of independent, autonomous 10-25 kW rated DS units in a large solar farm.
A dynamic model of the DS system is presented in this thesis, including models of the Stirling engine working gas and mechanical dynamics. Custom FORTRAN code is written to model the Stirling engine dynamics within PSCAD/EMTDC. The Stirling engine and various other components of the DS system are incorporated into an electrical network, including first a single-machine, infinite bus network, and then a larger 12-bus network including conventional generators, loads, and transmission lines. An analysis of the DS control systems is presented, and simulation results are provided to demonstrate the system's steady state and dynamic behavior within these electric power networks. Potential grid interconnection requirements are discussed, including issues with power factor correction and low voltage ride-through, and simulation results are provided to illustrate the dish-Stirling system's capability for meeting such requirements.
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Brunner, Steffen. "Financing options for solar power projects The case of Edisun Power AG /." St. Gallen, 2005. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/02606770001/$FILE/02606770001.pdf.
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Guarracino, Ilaria. "Hybrid photovoltaic and solar thermal (PVT) systems for solar combined heat and power." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/58172.
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Solar is a particularly promising sustainable energy source in terms of its potential to displace the burning of fossil fuels for heat and power, heating and even cooling, albeit at a cost. The sun load-factor profile has a close and predictable match to the daily varying energy demand for heat and electricity, both thermal and electrical, and thermal storage for periods of low irradiance can be made readily available. In addition, solar thermal technologies can provide a significant fraction of the hot water demand in households, as well as space heating and cooling in residential buildings and for industrial facilities. In fact, solar heating has been proposed as one of the leading solutions in terms of its potential for greenhouse gas abatement [1]. At the small scale, photovoltaic systems presently dominate the domestic solar market with solar to electrical conversion efficiencies of around 15% and at a competitive cost for the building owner. Solar photovoltaic installations were encouraged in Europe at the local level with financial support and now constitute a large and mature market with continuously falling prices. Solar thermal systems are able to make use of a larger proportion of the solar resource as they convert solar energy into heat with a higher efficiency than the PV conversion efficiency. Moreover, the low temperature heat may be used to satisfying the largest portion of the demand for thermal energy that is currently met by fossil fuels. The development of the solar thermal market is strongly dependent on the availability of the local irradiance level and on the cost of the alternative sources of thermal energy. In some countries in Europe the solar thermal market is quite mature (e.g. Austria), whilst in others, such as in the UK, solar thermal energy still contributes marginally to the energy mix and solar thermal systems are not yet cost competitive. Due to the high costs of solar thermal energy systems, these constitute a relatively small market at present with the potential to grow substantially in the near future. A competitive solution for energy (heat and power) provision in buildings is the development of combined solar photovoltaic/thermal (PVT) systems which produce both electricity and heat simultaneously from the same aperture area. This solution is particularly suited to residential applications in urban areas, where the demand for electricity is accompanied by a demand for low temperature heat, and space for solar installations is scarce. Many alternative technologies for PVT integration exist and PVT units can be coupled with various systems for domestic hot water generation and/or space heating. At the design stage of a PVT system, decisions have to be made on the absorber characteristics (consisting of thermal collector and PV laminate), on the thermal to electrical yield ratio and on the application (industrial or residential application, stand alone or grid connected). These design parameters influence the requirements on the fluid temperature and electricity output, and the overall efficiency. In addition, system control can significantly impact the potential of such systems in terms of their performance characteristics in different applications. The aim of this present research effort was to demonstrate the technical and practical feasibility of a novel, high-efficiency hybrid PVT water system, by considering an affordable, small-scale, modular unit that can be scaled easily to cater to varying demand levels. The research investigated the technical issues related to PVT panel technology, by looking in particular at the optical efficiency of the PV cells, at the heat transfer from the PV cells to the fluid, and at the integration of such a unit in a heat and power provision system that attempts to match generation and local demand. A detailed numerical model was developed that constitutes a tool for testing various collector and system designs. The model was validated against experimental data. An experimental apparatus was designed and constructed for the purpose of evaluating the collector model and for collecting a database of performance data on PVT collectors. Collector performance data are scarce at the moment due to the relatively small market size, thus the work constitutes a reference for further development and analysis of this type of collectors. Steady-state tests and dynamic tests were performed on PVT collectors and the results were used to develop a reliable model of collector performance over a wide range of time-varying operating conditions. The model allowed for assessments of various solar PVT system designs under different operating conditions and control strategies. Result showed that such systems may underperform if their operation and design is not designed specifically for the local weather conditions and user-demand specific requirements. It is envisaged that emissivity control applied to the solar cells should be adopted for PVT system application, especially if higher operating temperatures are required (e.g. in combination with thermally driven/heat powered cooling systems). The numerical model confirms that solar cells a with low emissivity coating can maximise the thermal energy output of a PVT system. The potential of improved PVT systems is finally assessed from an economic perspective, in an analysis that considers the potential cost reduction of PVT systems in relation to alternative technologies used as a benchmark.
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Abiose, Kabir. "Improving the concentrated solar power plant through connecting the modular parabolic solar trough." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105718.
Full textAbstract:
Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.Cataloged from PDF version of thesis.
Concentrating solar power (CSP) stands as a promising renewable energy technology with the ability to contribute towards global reduction of carbon emissions. A major obstacle to increased adoption of CSP plants has to do with their high initial investment cost; consequently, there is a powerful desire to find improvements that decrease the initial capital investment for a CSP plant. One such improvement involves connecting modularized parabolic trough segments, each with the same dimensions, decreasing the overall amount of actuators required along with greatly simplifying system control architecture. This thesis is concerned with the extent to which parabolic solar trough modules can be connected together while still being able to operate to desired accuracy under expected load. Accuracy requirements are calculated, along with expected loads resulting in frictional torque on the trough. These expected loads are combined with a model for the effect of connecting multiple trough modules to generate a relationship between number of chained modules and required torsional stiffness. To verify said model, an experimental setup was designed and constructed to simulate loads due to both trough weight and wind loads.
by Kabir Abiose.
S.B.
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Sheu, Elysia J. (Elysia Ja-Zeng). "A solar reforming system for use in hybrid solar-fossil fuel power generation." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/103734.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 229-241).
As demand for energy continues to rise, the concern over the increase in emissions grows, prompting much interest in using renewable energy resources such as solar energy. However, there are numerous issues with using solar energy including intermittency and the need for storage. A potential solution is the concept of hybrid solar-fossil fuel power generation. Previous work has shown that utilizing solar reforming in conventional power cycles has higher performance compared to other integration methods. In this thesis, a two level analysis of a hybrid redox redox cycle is performed. First, a system analysis of a hybrid cycle utilizing steam redox reforming is presented. Important cycle design and operation parameters such as the oxidation temperature and reformer operating pressure are identified and their effect on both the reformer and cycle performance is discussed. Simulation results show that increasing oxidation temperature can improve reformer and cycle efficiency. Also shown is that increasing the amount of reforming water leads to a higher reformer efficiency, but can be detrimental to cycle efficiency depending on how the reforming water is utilized. Next, a system analysis for a CO2 redox reforming hybrid cycle and comparison of cycle and reformer performance between a CO 2 redox reformer and steam redox reformer hybrid cycle are presented. Similar to the steam redox system, results show that increasing the oxidation temperature or the amount of reforming CO2 leads to higher reformer and cycle efficiencies. In addition, the comparison between the CO2 and steam redox reformer hybrid cycles shows that the CO2 cycle has the potential to have better overall performance.Based on the system analysis, a reformer level analysis is also performed. A novel receiver reactor concept for a solar steam redox reformer is presented, and a computational model is developed to assess its performance. The receiver-reactor consists of a dumbbell shape absorber system that has two distinct absorbers. This absorber system setup allows for the switching between reduction and oxidation steps without having to constantly change inlet streams to the reactor and is designed such that the inlet connections do not interfere with the solar window. In addition, at any point in time only one solar absorber is irradiated by the solar energy (during the reduction step). Simulation results show that the receiver-reactor strongly absorbs the solar radiation and most of the radiative heat transfer occurs in the front half of the reactor. Moreover, results show that higher conductivity absorber materials are more suitable for long term reactor operation. A sensitivity analysis is also performed for the solar steam redox reformer with respect to different performance metrics. Important parameters include channel size, inlet temperature, and reformer pressure. Moreover, a strategy for reactor design based on performance as well as integration with the power cycle is discussed.
by Elysia J. Sheu.
Ph. D.
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Kim, Byungyu. "Solar Energy Generation Forecasting and Power Output Optimization of Utility Scale Solar Field." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2149.
Full textAbstract:
The optimization of photovoltaic (PV) power generation system requires an accurate system performance model capable of validating the PV system optimization design. Currently, many commercial PV system modeling programs are available, but those programs are not able to model PV systems on a distorted ground level. Furthermore, they were not designed to optimize PV systems that are already installed. To solve these types of problems, this thesis proposes an optimization method using model simulations and a MATLAB-based PV system performance model. The optimization method is particularly designed to address partial shading issues often encountered in PV system installed on distorted ground. The MATLAB-based model was validated using the data collected from the Cal Poly Gold Tree Solar Field. It was able to predict the system performance with 96.4 to 99.6 percent accuracy. The optimization method utilizes the backtracking algorithm already installed in the system and the pitch distance to control the angle of the tracker and reduces solar panels partial shading on the adjacent row to improve system output. With pitch distances reduced in the backtracking algorithm between 2.5 meters and 3 meters, the inverter with inter-row shading can expect a 10.4 percent to 28.9 percent increase in power production. The implementation and calibration of this optimization method in the field this spring was delayed due to COVID-19. The field implementation is now expected to start this summer.
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Nixon, Jonathan. "Solar thermal collectors for use in hybrid solar-biomass power plants in India." Thesis, Aston University, 2012. http://publications.aston.ac.uk/18722/.
Full textAbstract:
This thesis examined solar thermal collectors for use in alternative hybrid solar-biomass power plant applications in Gujarat, India. Following a preliminary review, the cost-effective selection and design of the solar thermal field were identified as critical factors underlying the success of hybrid plants. Consequently, the existing solar thermal technologies were reviewed and ranked for use in India by means of a multi-criteria decision-making method, the Analytical Hierarchy Process (AHP). Informed by the outcome of the AHP, the thesis went on to pursue the Linear Fresnel Reflector (LFR), the design of which was optimised with the help of ray-tracing. To further enhance collector performance, LFR concepts incorporating novel mirror spacing and drive mechanisms were evaluated. Subsequently, a new variant, termed the Elevation Linear Fresnel Reflector (ELFR) was designed, constructed and tested at Aston University, UK, therefore allowing theoretical models for the performance of a solar thermal field to be verified. Based on the resulting characteristics of the LFR, and data gathered for the other hybrid system components, models of hybrid LFR- and ELFR-biomass power plants were developed and analysed in TRNSYS®. The techno-economic and environmental consequences of varying the size of the solar field in relation to the total plant capacity were modelled for a series of case studies to evaluate different applications: tri-generation (electricity, ice and heat), electricity-only generation, and process heat. The case studies also encompassed varying site locations, capacities, operational conditions and financial situations. In the case of a hybrid tri-generation plant in Gujarat, it was recommended to use an LFR solar thermal field of 14,000 m2 aperture with a 3 tonne biomass boiler, generating 815 MWh per annum of electricity for nearby villages and 12,450 tonnes of ice per annum for local fisheries and food industries. However, at the expense of a 0.3 ¢/kWh increase in levelised energy costs, the ELFR increased saving of biomass (100 t/a) and land (9 ha/a). For solar thermal applications in areas with high land cost, the ELFR reduced levelised energy costs. It was determined that off-grid hybrid plants for tri-generation were the most feasible application in India. Whereas biomass-only plants were found to be more economically viable, it was concluded that hybrid systems will soon become cost competitive and can considerably improve current energy security and biomass supply chain issues in India.
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Björkman, Nils. "Heliostat Design." Thesis, KTH, Maskinkonstruktion (Inst.), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-157159.
Full textAbstract:
A heliostat is a motorized mirror used in a Solar Power Tower plant. The technology has been around since the 1970’s, and involves hundreds or thousands of heliostats reflecting the sun’s rays to the top of a high tower, where the incident solar energy is converted to heat energy, which in turn is used to drive steam turbines and produce electricity. Demonstration plants have been built in the U.S.A. and Spain, and a number of new facilities have been added since 2005. To achieve a commercial breakthrough, the technology must be made more efficient so that electricity can be produced at prices comparable with other options such as wind, photovoltaic, nuclear and coal. A critical component in the economics of the Solar Power Tower plant is the cost of the heliostat, which is estimated to account for approximately 50 % of the investment cost of the total plant. This report deals with the heliostat from a multifaceted perspective. Different design approaches are explained. First, mirror geometries, with manufacturing dimensions, for a rotation-symmetric paraboloid-shaped mirror-assembly are obtained for mirrors with different sizes with a Matlab code. Investigating wind loads are among the most important tasks in a heliostat development project, as large wind loads radically complicates the design work. A wind load calculation-method based on previous work by Sandia National Laboratories and finite element method (FEM) is used in this work to design heliostats to withstand expected wind loading. The design of the geometry and the structure to withstand wind loading is illustrated with two azimuth elevation heliostats (25 m 2 and 49 m2). Finally, a number of innovative technical solutions are suggested. These are a new mirror facet mounting technique, sliding bearings, elevation drive, and a very unique azimuth motor module, which uses steel wires as belts with an integrated brake. It is hoped that the results and designs presented in this thesis will be a good foundation for further research in the heliostat structures and heliostat controls at the Robotics lab in IISc and elsewhere. Keywords: Solar Power, Heliostat, Thermal solar power, Solar Power Tower, Central Receiver SystemEn heliostat är en motordriven spegel som används i tornsolkraftverk, kända som Solar Power Tower, även kallade Central Receiver system. Tekniken har funnits sedan 1970-talet och går ut på att hundratals eller tusentals heliostater speglar solstrålarna till toppen av ett högt torn, där stålningsenergin omvandlas till värmeenergi, som t.ex. kan användas till att driva ångturbiner och producera elektricitet. Demonstrationsanläggningar har byggts i bland annat USA och Spanien, och ett flertal nya installationer har tillkommit sedan år 2005. För att verkligen nå ett kommersiellt genombrott måste tekniken göras billigare så att solelen kan produceras till minst lika bra pris som andra alternativ, så som t.ex. solceller, kärnkraft och kolkraft. En kritisk komponent för tornsolkraftverkens ekonomi är kostnaden för heliostaterna, som beräknas stå för ungefär 50 % av anläggningens totala investeringskostnad. Den här rapporten avhandlar heliostaten ur ett mångfacetterat perspektiv där olika konstruktionsspår förklaras. Vidare behandlar rapporten spegelgeometrier, och en Matlab-kod som genererar tillverkningsmått för en rotationssymmetrisk paraboloidformad spegelyta finns bifogad. Att undersöka vindlaster är bland det viktigaste i ett heliostatutvecklingsprojekt, eftersom dessa är de dimensionerande lasterna för designarbetet. Här används en vindlastberäkningsmetod utgiven av Sandia National Laboratories, som kortfattat går ut på att man multiplicerar det dynamiska vindtrycket med en korrigeringsfaktor som baserats på emiriska studier av heliostatmodeller i vindtunnel. En dimensioneringsprocess för heliostater föreslås och utvecklingsgången för två Azimut-Elevation heliostater i storlek 25 m 2 resp. 49 m2 demonstreras. FEM-mjukvara nyttjas som det främsta verktyget för att dimensionera heliostatkonstruktioner som kan stå emot vindlasterna. Slutligen ges förslag på innovativa tekniska lösningar för spegelmontering, glidlager, montering av elevation-motorerna, och en unik azimut-motormodul, vilken använder stålvajrar som remmar och har en integrerad broms. Med all denna information bör Robotics Lab på IISc ha en god grund att stå på inför vidare forskning inom konstruktion och styrning av heliostater. Nyckelord: Solenergi, Heliostat, Termisk solenergi, Solar Power Tower, Tornsolkraftverk
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Ray, Mike C. T. "Solar Data Analysis." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1078.
Full textAbstract:
The solar industry has grown considerably in the last few years. This larger scale has introduced more problems as well as possibilities. One of those possibilities is analyzing the data coming from the sites that are now being monitored, and using the information to answer a variety of questions.
We have four questions which are of prime importance identified in this thesis:
1. Can data from customers be trusted?
2. Can we use data from existing sites to determine which sites need the most improvement?
3. Can we implement a location-based algorithm to reduce the amount of false positives for performance, or other alarms?
4. Can we improve upon the current predicted power algorithm?
We find that not only can we answer these questions definitively, but the improvements found are of significant value. Each of these items represents an important question that either directly or indirectly translates into increased revenue and engineering improvements for the solar industry as a whole.
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ZHANG, SHAN. "Analytical system for photovoltaic and concentratingsolar power generation." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-16174.
Full textAbstract:
Energy is the material foundation of human survival and development. Throughout human industrialization process, the fossil energy has made tremendous contributions in the progress of human civilization, economic and social development. For a long time, the development of human energy use patterns makes fossil fuels rapidly depleted and the consequences of environmental deterioration by this pattern lead to the severe challenge for mankind. Many countries start paying more attention to develop the new energy. The solar electricity production system is one of the main new energy power generations. The thesis is a guide of principle for solar power generation system. It focuses on comparisons between photovoltaic and concentrating solar power generations and analysis of their market prospects. The merits and demerits of these two systems will also be pointed out in this thesis.
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Thapar, Sapan. "Policy analysis and growth determinants of solar and wind power sectors in India." Thesis, IIT Delhi, 2019. http://eprint.iitd.ac.in:80//handle/2074/8056.
Full text
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Protogeropoulos, Christos I. "Autonomous wind/solar power systems with battery storage." Thesis, Cardiff University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320875.
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Omer, Siddig Adam. "Solar thermoelectric system for small scale power generation." Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/7440.
Full textAbstract:
This thesis is concerned with the design and evaluation of a small scale solarthermoelectric power generation system. The system is intended for electricity generation and thermal energy supply to small scale applications in developing countries of the sunny equatorial regions. Detailed design methodologies and evaluations of both the thermoelectric device and the solar energy collector, which are parts of the combined system, are presented. In addition to experimental evaluations, three theoretical models are presented which allow the design and evaluation of both the thermoelectric module and the solar energy collector. One of the models (a unified thermoelectric device model) concerns the geometrical optimization and performance prediction of a thermoelectric module in power generation mode. The model is unified in the sense that it accounts for the effect of all the parameters that contribute to the performance of the thermoelectric module, a number of which are ignored by the available design models. The unified model is used for a comparative evaluation of five thermoelectric modules. One of these is commercially available and the others are assumed to have optimum geometry but with different design parameters (thermal and electrical contact layer properties). The model has been validated using data from an experimental investigation undertaken to evaluate the commercial thermoelectric module in power generation mode. Results showed that though the commercially available thermoelectric cooling devices can be used for electricity generation, it is appropriate to have modules optimized specifically for power generation, and to improve the contact layers of thermoelement accordingly. Attempts have also been made to produce and evaluate thermoelectric materials using a simple melt-qucnching technique which produces materials with properties similar to those of the more expensive crystalline materials.
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Cohen, Jeremy Michael M. Eng Massachusetts Institute of Technology. "Peak power tracking for a solar buck charger." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/61153.
Full textAbstract:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 91-92).
This thesis discusses the design, implementation, and testing of a buck converter with peak power tracking. The peak power tracker uses a perturb and observe algorithm to actively track the solar panel's peak power point and a global sweep algorithm accounts for startup and multiple local maxima. The tracker takes the place of the current mode loop in the converter's control scheme by providing a battery with peak charging current. A voltage mode loop is also designed to take over control from the tracker to complete the multi-loop structure. A solar panel simulator is designed to mimic the characteristics of an actual solar panel to allow careful testing of the tracking algorithms. A test circuit board is built and its operation is verified. Finally, the power extracting potential of the active tracking method from this thesis is compared to two simpler solar regulators.
by Jeremy Michael Cohen.
M.Eng.