Thèses : « SOLAR WATER PUMPING APPLICATION »

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SHALINI. « DESIGN AND CONTROL OF CONVERTERS FOR SOLAR WATER PUMPING APPLICATION ». Thesis, DELHI TECHNOLOGICAL UNIVERSITY, 2021. http://dspace.dtu.ac.in:8080/jspui/handle/repository/18895.

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This thesis presents designing and modelling of water pumping system powered by solar energy and comprising of BLDC motor drive. It manifests the performance comparison between Zeta, Sepic and Cuk converter based output conditioning of SPV array as well. As the solar insolation level is not constant, SPV array output is controlled using Maximum Power Point Tracking (MPPT) along DC-DC converter in order to ensure maximum power usage from SPV array. MPPT is implemented using Incremental Conductance (INC) algorithm along with Zeta, Sepic and Cuk converters to power BLDC motor drive. The DC- DC converters along with the entire simulation are analyzed for peak insolation level as well as varying insolation level and comparison has been performed on the basis of performance characteristics. The BLDC motor is fed using a six-pulse converter which is controlled using Space Vector Pulse Width Modulation (SVPWM) technique which facilitate maximization of efficiency of whole system. The simulation results are obtained from model created in MATLAB (Simulink) environment.

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Wong, Yuen-wah, et 黃婉華. « Performance prediction model for a solar water pump ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31223722.

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Wong, Yuen-wah. « Performance prediction model for a solar water pump / ». Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21607424.

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Bengtsson, Niclas, et Johan Nilsson. « Solar Water Pumping for Irrigation : Case Study of the Kilimanjaro Region ». Thesis, Högskolan i Halmstad, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-28629.

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This study has been conducted as a Minor Field Study (MFS). It focuses on solar water pumping for small-scale farmers in the Kilimanjaro Region of Tanzania. The purpose is to investigate the possibilities for rural farmers to operate their irrigation with solar power instead of their current option: fossil fuels, primarily petrol. The study was conducted in three phases, starting with pre-study in Sweden, followed by field study in Tanzania from January to March 2015 and finishing with summarizing and calculating in Sweden. Fuel powered water pumping has a cheap capital cost; however, it is expensive and problematic to maintain and operate. Solar powered water pumping is almost completely opposite. It has a higher initial cost; however, it is considerably cheaper to run. The results indicate that the investment in solar power might be too expensive for the farmers, as long as they do not receive external financial and educational support. Assuming that the farmers are able to obtain a solar water pumping system, results show that they will benefit and save a considerably amount of money over a long period of time. Also, solar water pumping is environmentally friendly compared to the systems in Tanzania today.

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Liyanage, Damitha P. « Simulation, design and testing of a microprocessor controlled photovoltaic water pumping system ». Thesis, University of Reading, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386751.

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Makhomo, Selbourne Rapoone. « Remote monitoring and evaluation of a photovoltaic (PV) groundwater pumping system ». Thesis, Cape Peninsula University of Technology, 2005. http://hdl.handle.net/20.500.11838/1270.

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Thesis (MTech (Technology))--Cape Peninsula University of Technology, 2005
Potable water, and especially the accessibility to it, is an essential part of everyday life. Of particular note, is the challenge that residents of remote rural African villages face in order to gain access to this basic requirement. Specifically, the rural areas in the Northern Cape (Province north of Cape Town) region in South Africa is one such example that illustrates this problem very well. In order to address the requirements for drinkable water, various types of water pumping technologies have been used. Up to now, the two competing water pumping systems, diesel and photovoltaic (PV), have been the primary technologies deployed in selected sites in the Northern Cape. The manual data collection of water pumping system data in the Northern Cape is fraught with impracticalities such as travel costs and requirements for skilled personnel. Therefore, as a preliminary step to accelerate development and testing, a local experimental laboratory PV water pumping rig was set-up within the Department of Mechanical Engineering at the Cape University of Technology. A short-term analysis was performed over a period of three weeks on the rig and the experimental results indicated the following: array efficiency of 16.3%, system efficiency of 15.0% and an average system efficiency of 1.47%. However, the results do indicate that long-term monitoring of PV water pumping systems can be suitable in serving to determine dynamic system performance and system life cycle costs. The purpose of this project is two-fold - firstly, to present the results on the work done on the experimental PV system.

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Sivakumar, Karthik. « An Internship on Developing a Solar Water Pumping System at Microsol International™ ». Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1303750359.

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El, Safi Osman E. O. « The use of power electronic interface in the efficacious utilization of power in photovoltaics pumping systems ». Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253822.

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Wernius, Emma, Hanna Olausson et Martina Sekkenes. « Optimization of a solar water pumping system in Progreso, Amazonas, Colombia : Minor field study ». Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-256038.

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In the villages along the Amazon river, the access to clean drinking water is lacking. In Progreso, the Swedish foundation Ankarstiftelsen and the non-governmental organization Entropika have installed a water purification system to solve this problem. The water used in the purification system is today pumped from a tributary to the Amazon river with a gasoline pump. This comes with social, ecologic and economic problems. To solve these problems, a solar water pumping system has been developed. After a preparing literature study on the topic, a field study was done to find relevant data. From this, an Excel program was made to optimize a suitable solution. Together with suggestions from three companies, two with a surface pump and one with a submersible pump, the system including a submersible pump was considered the most preferable. This mainly due to lower cost, weight and maintenance. Further, the suggestions were used to control the accuracy of the developed Excel program. This program can be used for future optimizations of systems with similar character.
I byarna längs Amazonfloden är tillgången till rent dricksvatten bristfällig. Organisationerna Ankarstiftelsen och Entropika är verksamma i området och arbetar för en ökad levnadsstandard åt lokalbefolkningen. I byn Progreso har organisationerna installerat ett vattenreningssystem för att lösa problemet. Systemet använder flodvatten som renas med sandfilter och sedimentering. Vattnet pumpas idag från en biflod till Amazonfloden med en bensindriven pump. Pumpen är mycket stöldbegärlig och måste därför bäras ner till floden vid varje användning. Den väger 70 kg och utgör en arbetsbörda för vattenmästaren i byn. Utöver det är regelbundna kostanden för drivmedlet ett problem då invånarna saknar en stabil inkomst. Dessutom orsakar den bensindrivna pumpen miljöfarliga utsläpp. För att lösa de sociala, ekonomiska och ekologiska bristerna har ett solvattenpumpssystem dimensionerats. Efter en förberedande litteraturstudie inom ämnet utfördes en fältstudie i Progreso för att hitta relevanta data. Fältstudien bestod av distansmätningar och intervjuer med invånarna. Intervjuerna gav svar på huruvida dagens system fungerar samt det önskade vattenbehovet från det nya systemet. Med funna data kunde beräkningar utföras och ett Excelprogram utvecklas för att optimera ett för platsen passande system. Från tre systemförslag framtagna av företag, två förslag med ytpump och ett med en dränkbar pump, togs beslutet att den dränkbara pumpen var att föredra. Detta främst på grund av lägre kostnad, vikt och underhåll. Vidare användes förslagen för att undersöka pålitligheten hos Excelprogrammet som ämnar till att används för framtida system av liknande karaktär.

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Davies, Neale. « Novel, induced flow, centrifugal water pumping system for off grid application ». Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2037461/.

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Water provision in rural areas represents a significant challenge, especially within the context of resource and sanitation in developing countries. High set-up costs, lack of installation expertise and reliability issues, arising from fluctuating operational conditions, have prevented many people from receiving the full benefit of automated pumping systems. The specific aim of this thesis is to assess the feasibility of using a tunable, induced flow subsystem as a means of optimising the power utilization and performance of a centrifugal pump over a wider range of operating conditions than typically expected. More generally, the research presented is undertaken to reduce the high implementation costs and localised limitations of rural water pumps by developing the theory towards a ‘’one-size-fits-all’’ pumping system. The theoretical analysis of an induced flow centrifugal pumping system is presented, coupled with the analogous electrical system. The results of simulations performed using both systems are compared to experimental results, obtained using an induced flow subsystem (IFS) test rig constructed at the University of Liverpool. All sets of results demonstrate consistent IFS characteristics, identifying its capability to maintain maximum power point (MPP) operation of the centrifugal pump irrespective of load. Further, the experimental results reveal a boost in output pressure which enables the pump to achieve an improved hydraulic power and increased operating range over the same system without an IFS. It is concluded that, through the addition of an IFS, the performance of a centrifugal pump may be decoupled from its operating head, expanding its range of serviceable conditions and demonstrating potential to develop a ‘’one-size-fits-all’’ system. Ultimately, this could offer a cheaper and more reliable supply of a resource which is vital to life in any rural location: clean water.

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Merlini, Maurizio. « Implementation and validation of a design model for photovoltaic water pumping system (PVPS) ». Thesis, KTH, Skolan för kemivetenskap (CHE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145860.

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Desertification is one of the main problems plaguing the Chinese countryside. The main cause is the heavy overgrazing of pastures and in this context the irrigation can be a solution to the problem. As regard the existent irrigations systems, pumps are driven manually or by diesel engines. Actually the use of electric motors would be a better solution for the irrigation development, but the lack of the access to electric network for the isolated rural areas represents a great obstacle. Therefore the use of PV stand-alone systems to produce the electricity for the motor-pumps (PVPS- Photovoltaic Pumping Systems) represents a both economic and technical good solution. However the weak point for PVPS diffusion is lack of tools to design these systems and predict their performances. This thesis work wants to provide a sizing software and the technical guidelines to select the suitable components for a PVPS. The developed sizing method has been validated applying it to two real cases where PVPS were already existing. Then, the obtained results have been compared with the characteristics of the real PVPS. The reliability of the design procedure has been verified, observing the similarity between the calculated outputs and the respective real values. Finally simulations have been done using the designed PVPS. The scope of those simulations has been to add some technical recommendations useful for the PVPS designer. The influence of the total head variations on the pumping performance and also the effect of the motor-pump subsystem choice on the final power size of PV array have been investigated.

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Craig, Rob James. « Modelling of a thermodynamically driven heat engine with application intended for water pumping ». Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95923.

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Nyanue, William Grear. « A manual-pneumatic pump for rural water supply ». Thesis, The University of Arizona, 1985. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1985_128_sip1_w.pdf&type=application/pdf.

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Coppola, Emery A. « Optimal pumping policy for a public supply wellfield using computational neural network with decision-making methodology ». Thesis, The University of Arizona, 2000. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_2000_395_sip1_w.pdf&type=application/pdf.

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Kalogirou, Soteris A. « The application of solar desalination for water purification in Cyprus ». Thesis, University of South Wales, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282712.

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Olsson, Alexander. « An evaluation of solar powered irrigation as carbon offset projects ». Licentiate thesis, KTH, Energiprocesser, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-188562.

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Carbon offsets have been developed as one tool to incentivise investments by developed nations in climate change mitigation activities in developing countries. The carbon offsets can be used towards the countries’ own mitigation targets but are also meant to benefit developing countries by providing a pathway to clean development. Photovoltaic water pumping (PVWP) technology is a solution to use PV for irrigation, which can be used to restore degraded grasslands and help farmers adapt to climate change. Restoration of degraded grasslands increases the production of grass and will therefore increase the amount of carbon in the soil, a process that may mitigate climate change. However, poor farmers often have limited access to irrigation technology and this thesis assesses how carbon offsets may bring revenues to increase adaption of PVWP technology in remote areas of the Chinese grasslands. PV modules can be used to mitigate climate change in different ways; the most common is to produce electricity to replace fossil fuel power capacity. The novelty of this thesis is that it assesses the alternative mitigation possibilities for the PVWP project proposed here. Further, consideration of water constraints that limit the applicability of the technology and a framework to assess the trade-offs between potential downstream water impacts and environmental co-benefits of the project add to the novelty of this thesis. Policy barriers for the project will also be considered. Used to restore severely degraded grasslands, PVWP projects show high carbon sequestration potential and successfully compete with grid electricity as carbon offset projects. A case is analysed and it shows that the carbon market could play a role in increasing the feasibility of PVWP projects. However, water issues make project implementation very site-specific and some indicators to determine feasibility is proposed to be blue water availability, evaporation recycling ratio and water productivity. Water use must also be looked at with respect to climate, food and energy security, calling for a nexus approach to evaluate the project suitability. In May 2016, grassland management projects are excluded from the Clean Development Mechanism to the Kyoto Protocol, and this limits project implementation to the voluntary markets.
Avhandlingen är ämnad att läsas av beslutsfattare inom klimatområdet samt aktörer på de olika klimatkompensationsmarknaderna. Klimatkompensation har utvecklats som ett verktyg för att stimulera industriländers investeringar i klimatprojekt i utvecklingsländer. Klimatkompensation kan användas för att nå industriländernas egna klimatmål men är också tänkta att gynna utvecklingsländer genom att tillhandahålla en ”ren” utvecklingsmöjlighet. Solcellsdrivna vattenpumpar (eng. photovoltaic water pumping: PVWP) är en teknik för att använda solceller för bevattning. Tekniken kan användas för att restaurera degraderade gräsmarker och för att hjälpa jordbrukare anpassa sig till klimatförändringarna. Restaurering av gräsmarker ökar produktionen av gräs vilket medför ökad mängden kol i marken, en process som kan mildra klimatförändringarna. Men fattiga bönder har ofta begränsad tillgång till bevattningsteknik och denna avhandling utvärderar hur klimatkompensation kan ge intäkter för att öka användningen av PVWP i avlägsna delar på den kinesiska slätten. Solceller kan användas för att mildra klimatförändringarna på olika sätt och vanligast är att producera el för att ersätta fossila bränslen. Det är därför viktigt att titta på alternativkostnaden för PVWP-projekten som föreslås här. Vidare begränsar vattentillgången projekten och ett ramverk för att tydliggöra avvägningar mellan vattenrelaterade problem och miljömässiga fördelarna med ett projekt är nödvändigt. Klimatpolitiska styrmedel sätter också upp vissa begränsningar för projekten. Om PVWP används för att återställa mycket degraderade gräsmarker, visar projekten hög klimatnytta och de kan framgångsrikt konkurrera med solel till nätet som klimatkompensationsprojekt. En fallstudie visar att klimatkompensationsmarknaden skulle kunna spela en viss roll för att öka antalet PVWP-projekt. Däremot gör vattenfrågan projektens geografiska plats viktig och indikatorer för att avgöra genomförbarheten föreslås vara ”blåvattentillgång”, ”förångningsåtervinning” och ”vattenproduktivitet”. Vattenanvändningen måste också ses i förhållande till klimat, mat- och energisäkerhet, vilket kräver en nexusstrategi för att utvärdera projekten. I skrivande stund (maj 2016) är projekt rörande skötsel av gräsmarker exkluderade från mekanismen för ren utveckling (CDM) till Kyotoprotokollet och detta begränsar projekten till de frivilliga klimat-kompensationsmarknaderna.

QC 20160711

Demonstration and Scale-Up of Photovoltaic Solar Water Pumping for the Conservation of Grassland and Farmland in China

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Kler, Rantej Singh. « Metal oxide nanomaterials and their application in solar photoelectrolysis of water ». Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/48904/.

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Solar generated hydrogen as an energy source is green, sustainable, with a high energy density. One day the majority of current fossil fuel based technology could be replaced with hydrogen technology reducing CO2 emission drastically. The goal in this research is to explore hybrid metal oxide photocatalysts in the pursuit of achieving highly efficient photoanodes for use in photoelectrochemical cells (PEC). Achieving high efficiencies of hydrogen production in photoelectrochemical cells is the key challenge for the commercialisation of PEC technology as a viable, sustainable, hydrogen source; limited only by the lifetime of the sun and the resources of the metal oxide materials. In this research TiO2, Fe-Ti-O, ZnO, and Zn2TiO4 are the photocatalysts explored. Alloys of Ti-Fe-O showed improvement over TiO2, whilst a hybrid heterostructure of ZnO/Zn2TiO4/TiO2 enhanced photocurrent densities significantly. A barrier layer in the photoanode achieved localised exciton separation and reduction of recombination rates by inhibiting back flow of electrons after injection into the TiO2 layer. Nanotubes are created by the simple electrochemical process of anodisation. The nanotube composition depends on the anode material. To control the composition ofthe anode, iron and titanium are co-deposited onto a substrate using electron beam evaporation. The introduction of iron into titania nanotubes engineered the band gap, lowering the band gap energy to that of iron oxide whilst the positions of the conduction and valence bands with respect to the oxidation and reduction potentials of water remained favourable. Fe-Ti-O nanotubes showed remarkable photocurrent density improvement compared to TiO2 nanotubes. ZnO nanostructures deposited by vapour transport mechanisms showed variability in the morphology of the structures, as governed by the growth dynamics. Herein, it is shown that an electronically favourable situation arises by the formation of a ZnO-Zn2TiO4-TiO2 heterostructure and a high photocatalytic activity is reported. The structure is composed of a large surface area ZnO nanorod photoabsorber formed on a Ti foil which forms a Zn2TiO4 barrier layer between ZnO and TiO2. The Zn2TiO4 layer inhibits electron transport toward the surface of the photoanode whilst encouraging charge transport to the hydrogenation electrode. The heterostructure interfacial surface area is extended through the utilisation of TiO2 nanotubes, which demonstrated a 20.22 % photoelectrochemical efficiency under UV illumination. Surface modification of ZnO nanorods with aerosol assisted chemical vapour deposited TiO2 nanoparticles enhanced photocurrent densities of the ZnO rods, improving charge separation of excitons created within the TiO2 nanoparticles. ZnO nanotubes formed via a novel route using chemical bath deposition of ZnO is investigated, an annulus ZnO seed layer facilitated the site specific growth of ZnO nanotubes whilst a uniform seed layer formed ZnO nanorods.

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Pannila, Lankajith C. « Application of solar energy at Ohio highway rest areas ». Ohio : Ohio University, 1993. http://www.ohiolink.edu/etd/view.cgi?ohiou1175718933.

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Båverman, Gabriel, et Edris Tavoosi. « Evaluation of a solar powered water pumping system in Mutomo, Kenya : Comparison between a submersible induction motor and a PMSM system ». Thesis, Uppsala universitet, Elektricitetslära, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385439.

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An existing solar-powered water pumping system located in Mutomo, Kenya has beenevaluated in this paper. The requirement for this system is to produce a minimum of25m³ water per day throughout the year.The aim of this thesis is to investigate theperformance of the currently installed system and find a suitable replacement in termsof efficiency and economic viability. In order to acquire the necessary knowledge forthis project, a literature study was carried out to analyse the research within the area.Three simulation models were created which all include an electric motor driven by aphotovoltaic array and are connected to a submersible groundwater pump. Allmodels utilise space vector pulse width modulation. One model of an inductionmotor that represents the currently installed system, one induction motor thatdelivers a minimum of 25 m³ water per day, and one model of a permanent magnetsynchronous motor for comparison. Simulations using weather data, representing anaverage day for each month of the year were carried out. It was shown that thecurrently installed system does not fulfil the requirement of producing 25 m³ waterper day, and in addition produces a significant amount of energy that can not beutilised. It was also shown that the efficiency of the permanent magnet synchronousmotor was superior to the induction motors. In order to compare the systems interms of economic viability, price quotations from world leading manufacturers wereacquired. The results of the economic comparison show that the superior efficiencyof the permanent magnet synchronous motor was not enough to compensate for thehigher investment cost.

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Phiri, Esther. « Evaluating opportunities for sustainable rural water provision using solar PV in sub-Saharan Africa : a case study of Malawi ». Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/27397.

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Globally, approximately 663 million people lack access to safe drinking water sources and nearly half of these people live in Sub-Saharan Africa (SSA), where only 68% of the population has access to improved drinking water sources. Globally, it is estimated that 79% of the people using unimproved sources and 93% of people using surface water live in rural areas. In terms of water for agriculture, most of the countries in Sub-Saharan Africa rely on rain-fed agriculture, which is threatened by the effects of climate change thereby worsening food insecurity. Adequate provision of drinking and irrigation water is believed to enhance development in areas such as health, education, food security and women empowerment. This interdisciplinary study used a mixed methods approach to develop a financing and decision support model for planning and analysing of sustainable rural water provision using solar photovoltaics (PV) in SSA, with Malawi as a case study country. The research methods included household surveys, stakeholder interviews, field visits and techno-economic analysis. Findings from the household surveys show that the current water sources are inadequate; the majority of the households used boreholes as their main source of water and they faced challenges, which included queuing, low yield, non-functionality, disparity in number of water points, theft and vandalism. For irrigation, households still rely on traditional methods of irrigation namely; watering cans with very few having treadle pumps, which are all labour intensive. From the stakeholders point of view, challenges included lack of finances, failure of current community management system, lack of coordination and lack of enabling policies. In the techno-economic analysis, a solar PV system was designed to supply approximately 200 households with drinking water. The design cost was calculated to be US$18,600 and the levelized cost of water was US$0.34/m3. The levelized cost was found to be almost six times what the households are currently paying and three times what they are willing to pay. To address this issue, the study developed a cross-subsidy model for the cost of water with that of basic energy services, particularly rechargeable lantern lighting and mobile phone charging. Using this model, the levelized cost of water was reduced by over half but is still two and a half times what they are currently paying for water. Further innovations were found to reduce the breakeven cost to only US$0.06 more of what they are currently paying. The novelty of the research is that no work in SSA, particularly in Malawi has developed such an all-inclusive integrated needs-driven approach that helps identify solar PV powered water provision solutions. These results provide baseline data for researchers, policymakers, planners, entrepreneurs and other stakeholders with interest in providing water and energy to the rural areas. This thesis recommends that with proper finance and management policies, enforcement of product and installation standards and training of households, solar PV can be used to improve access for drinking and irrigation water and at the same time provide basic energy services to the people living in the rural areas of SSA.

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Gustafson, Joseph Rhodes. « Quantifying Spatial Variability of Snow Water Equivalent, Snow Chemistry, and Snow Water Isotopes : Application to Snowpack Water Balance ». Thesis, The University of Arizona, 2008. http://hdl.handle.net/10150/193330.

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This study quantifies spatial and temporal patterns in snow water equivalent (SWE), chemistry, and water isotopes associated with snowpack shading due to aspect and vegetation in the Valles Caldera National Preserve, New Mexico. Depth, density, stratigraphy, temperature, and snow chemistry, isotope, and biogeochemical nutrient samples were collected and analyzed from five snowpit locations on approximate monthly intervals between January-April 2007. SWE showed little variability between sites in January (~10mm) but differences expanded to 84mm (30%) by max accumulation in open sites and 153mm (45%) between all sites. Sulfate varied by 22% (10.6-13.5 microeq/L), Cl- by 35% (17.4-26.9 microeq/L), and d18O by 17% (-16.3 to -13.5), with SWE exhibiting inverse correlations with d18O (r2=0.96), SO42- (r2=0.75), and Cl- (r2=0.60) at max accumulation. Regression relationships suggest variability in SWE and solutes/water isotopes are primarily driven by sublimation. Mass balance techniques estimate sublimation ranges from 1-16% between topographically- and non-shaded open sites.

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Taheri, Najafabadi Amin. « Fundamental studies on solar-activated zeolite-supported photocatalysts for water splitting application ». Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42578.

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Robust calculations show that the incidence of solar energy on the earth’s surface by far exceeds all human energy needs. Undoubtedly, the most trusted way of utilizing solar energy is to convert and store it in the form of an energy carrier such as hydrogen. Semiconductors capable of absorbing light energy so-called photocatalysts can potentially drive water splitting reaction for hydrogen generation. In this research, fundamental studies on a new class of solar-activated supported photocatalysts for water splitting application are presented. This resulted in significantly higher rates of H₂ production in comparison to the existing supported TiO₂ series under visible light. The composition comprises silico-aluminates (zeolite) as the support, titanium dioxides (TiO₂) as the semiconductor, cobalt compounds as hydrogen evolution sites and heteropolyacids (HPAs) as multifunctional solid acids with excitability under visible light. Using this composition, I ended up with at least 2.6 times higher hydrogen evolution rates under visible light in comparison to Degussa P25, the best commercially available titania product. The chemical point of view of this successful combination was investigated, attributing the higher photocatalytic activity of the synthesized chemical compositions to the basicity of the matrix. The more basicity properties besides HPA presence can overcome the negative impacts of titania interactions with the zeolite which are band gap widening and anodic shift of the TiO₂ band edges. Furthermore, the effect of cobalt precursors (nitrates and chlorides) on the photocatalytic activity of the prepared photocatalysts was also investigated. Although nitrate-based photocatalysts exhibited an improvement in the UV-VIS absorbance spectra toward visible light, they caused an almost 30% lower H₂ production rate in comparison to the chloride salts. Overshadowing the poisoning and parasitic effects of Cl⁻ anions on the photooxidation sites in the zeolite-supported composition was another notable outcome of this study. This suggests emulation of the core-shell photocatalysis concept insofar with providing a reasonable distance between redox sites. The results indicate the importance of zeolite’s structural and chemical properties as the photocatalyst support. This can be addressed through the selection of suitable zeolite types, taking an important step in the development of visible-light-activated photocatalysts based on earth-abundant materials.

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Brito, Alaan Ubaiara. « Otimização do acoplamento de geradores fotovoltaicos a motores de corrente alternada através de conversores de frequência comerciais para acionar bombas centrífugas ». Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/86/86131/tde-05112018-160811/.

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O trabalho dedica atenção à otimização do acoplamento de geradores fotovoltaicos a motores de corrente alternada através de conversores de frequência comerciais, para acionar bombas centrífugas para fins de bombeamento de água. Procedimentos para otimização deste novo tipo de configuração são propostos. As ações de otimização são avaliadas através de ensaios experimentais realizados em uma bancada desenvolvida para este propósito. A bancada desenvolvida permite simular poços de até 100 m de profundidade. Resultados da operação de um protótipo instalado em campo são apresentados. Os resultados da pesquisa comprovam que este novo tipo de configuração é confiável e economicamente viável, podendo ser adotada como uma solução universal para sistemas de bombeamento de água que utilizam motobombas com potência igual ou superior a 1/2 CV.
This work is concerned with in the optimization of photovoltaic pumping systems that make use of a variable-speed drive and conventional induction motor with centrifugal pumps. Procedures for optimization of this new kind of configuration are proposed. The optimization actions are evaluated through experimental measurements accomplished in a test facility developed for this purpose. The developed test facility allows the simulation of wells with total head up to 100 m. Operation results of a prototype installed in the field are shown. The research results prove that this new kind of configuration is reliable and economically feasible, and could be adopted as a universal solution for water pumping systems with motors of 1/2 HP (metric) or higher.

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Sobenko, Luiz Ricardo. « Desenvolvimento de um kit de irrigação por microtubos com moto-bomba propulsionada por energia solar ». Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11152/tde-15082016-114217/.

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O bombeamento de água por meio da energia solar vem se mostrando uma alternativa para localidades onde outras fontes de energia não estão disponíveis ou são limitadas. Torna-se interessante aliar essa alternativa a um sistema de irrigação que opera com vazão e pressão relativamente baixas, como a irrigação localizada por microtubos, possibilitando assim a obtenção de alta eficiência. No presente trabalho teve-se por objetivo dimensionar e avaliar um kit de irrigação por microtubos, alimentado por bomba acionada com energia solar; e apresentar o custo e a economia de energia obtida com a utilização do kit desenvolvido. O kit foi composto por linhas laterais de irrigação, moto-bomba de deslocamento positivo (DC), gerador fotovoltaico, bateria, controlador de carga e válvulas solenóides. Assim, três etapas foram realizadas sendo o dimensionamento e avaliação dos emissores e das linhas laterais; a escolha e a avaliação do conjunto de bombeamento por energia solar; e, por fim, a instalação do kit em quatro canteiros de irrigação de cultivo de alface para avaliação do kit de irrigação. Em laboratório, as linhas laterais apresentaram \"excelente\" uniformidade (maior que 95,8%) para os três coeficientes de uniformidade avaliados; e a moto-bomba selecionada potencializou a irrigação de até 15 canteiros (270 m2) com rendimento de 10,8%. Nos canteiros, o sistema de irrigação também apresentou \"excelente\" uniformidade (maior que 94,7%) para os coeficientes avaliados. Nos maiores tempos observados, o sistema de bombeamento apresentou rendimentos do conjunto moto-bomba, de conversão e global de 9,7%, 36,6% e 2,4%, respectivamente. O custo fixo total de implantação do kit desenvolvido para a irrigação de 15 canteiros foi de R$ 4.313,33 com automação, ou R$ 3.088,33 sem automação. Na área e no período avaliado, o kit desenvolvido promoveu economia de energia de 4,5 kWh. Simulando-se o cultivo da alface por um ano, estimou-se uma economia de 63 kWh. Assim, o kit desenvolvido mostrou-se tecnicamente viável para irrigação da olerícola, observando-se a necessidade de equipamentos com diferentes características no mercado, que poderiam potencializar a eficiência do sistema.
The water pumping by solar energy has proven to be an alternative to locations where energy sources are not available or are limited. It\'s interesting to combine it with an irrigation system that operates with relatively low flow and low pressure, as drip irrigation with microtubes, in order to obtain high efficiency. The present study aimed to design and evaluate a microtubes irrigation kit, powered by solar energy pump; and show the cost and energy saving provided by the use of the kit developed. The kit was provided by lateral irrigation lines, positive displacement pump (DC), photovoltaic generator, battery, charge controller and solenoid valves. Three steps were followed: the design and evaluation of emitters and lateral lines; the selection and evaluation of the pumping set by solar energy; and the installation of the kit in four flowerbeds irrigating lettuce to evaluate the irrigation kit. In the laboratory, the lateral lines had \"excellent\" uniformity (greater than 95,8%) for the three uniformity coefficients evaluated; and the selected pump potentiated irrigation up to 15 flowerbeds (270 m2) with a 10.8% efficiency. In flowerbeds, the irrigation system also presented \"excellent\" uniformity (greater than 94.7%) for the evaluated coefficients. In the days when the irrigation time were higher, the pumping system presented motor pump set, conversion and overall efficiencies in the order of 9.7%, 36.6% and 2.4%, respectively. The total fixed cost of deployment kit developed for irrigation of 15 flowerbeds was R$ 4313.33 with automation, or R$ 3083.33 without automation. In the area and period evaluated, the developed kit promoted 4.5 kWh energy savings. Simulating the cultivation of lettuce for a year, a 63 kWh saving was estimated. Therefore, the kit developed proved to be technically feasible for lettuce irrigation, observing the need for equipment on the market with different characteristics that could increase the system efficiency.

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Rizvi, Syed Najeeb Ahmed. « Theoretical and experimental studies on the evaluation of pumps for photovoltaic powered water pumping and its application in Pakistan ». Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293870.

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Fendrich, Murilo Alexandre. « Solar concentration for the environment industry : photocatalytic materials and application technologies ». Doctoral thesis, Università degli studi di Trento, 2021. http://hdl.handle.net/11572/285695.

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This thesis presents the achievements pursued during the doctoral course. The work was carried out in the context of the project ERiCSol (Energia RInnovabile e Combustili SOLari), as part of the University of Trento strategic plan for the years 2017-2021. The project was conceived to establish an interdepartmental area to promote the challenge of developing scientific research and technological innovation to increase the competitiveness of Trento at national and international level in the areas of energy and environment. Among all the goals of the project, this work dedicates special attention to 1) development of novel materials for solar photocatalytic reactions and 2) use of renewable energy to push forward applications in water remediation. To accomplish these goals, the research brings a full collection of experimental activities regarding the employment of solar concentration for the environment industry and therefore this document is organized in 9 chapters. In chapter 1, it is presented the introduction outlining the overview of the environment industry, the employment of solar light as energy source and the general and specific objectives. Chapter 2 presents a literature review regarding the last 30 years of applications correlating the use of solar light towards wastewater purification. The chapter reviews the engineering features of solar collectors, photocatalyst materials employed and the panorama of the pollutants investigated up to the present date in solar photocatalysis, presenting comparisons between models and real wastewater approaches. Chapter 3 details the experimental techniques and characterizations employed to sustain the investigation proposed in the thesis. The first part of the chapter explains the features of parabolic dish solar concentrator designed and manufactured by the IdEA group at the physics department of the university of Trento. After, it is presented the pulsed laser deposition, a thin films fabrication technique employed to produce the photocatalysts used on water purification experiments. The second part of the chapter presents the description of the characterization techniques used to reveal the fabricated photocatalyst materials properties. Based on the review on the fundamentals of solar photocatalysis and the experimental techniques, chapters 4 and 5 present a discussion in the field of novel photocatalytic materials capable to operate under concentrated sunlight irradiation. Chapter 4 in special presents the investigation regarding the fabrication of tungsten trioxide (WO3) thin film coatings, bringing the novelty of using pulsed laser deposition as the fabrication method and the evaluation of this material in photocatalysis for the degradation of methylene blue dye model pollutant. Chapter 5 instead, presents the development on Zinc Oxide (ZnO) nanoparticles, bringing an innovative point of view on a “green-synthesis” approach and the material immobilization in film for heterogeneous photocatalysis routes. Chapters 6 and 7 discuss solar photocatalysis aiming to shift applications from model pollutants to real wastewater remediation conditions. Important comparisons are performed and discussed regarding the advantages and existing drawbacks. To fulfill this purpose, chapter 6 presents an application case of solar photocatalysis to the degradation of a surfactant-rich industrial wastewater whereas chapter 7 presents the approach focused on the remediation of organic lead contaminants present on a local water well site in the city of Trento. The last experimental approach of concentrated solar light is presented on chapter 8, dedicated to the application of concentrated sunlight towards waste biomass valorization. Conversely to the application on water previously described, this chapter presents the activity on designing, fabricating and coupling a hydrothermal reactor with concentrated sunlight using it as the driving force to promote degradation of grape seeds evolving into hydrochars with possible valorization of the carbonized material. Lastly, chapter 9 presents the conclusions and suggestions, this item expresses the final considerations on the results of the experimental investigations, advantages and limitations observed, and suggests possible actions for future works.

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Malin, Johansson. « Effects of water on dye/TiO2 interfaces : A spectroscopic study for solar cell application ». Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-162585.

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The processes of light harvesting by a sensitiser as in a nanoporous dye-sensitised solar cell, DSC, is a promising device for solar to electric energy conversion. The DSC systems have already reached conversion efficiencies exceeding 11%. This thesis considers water effects on dye absorbed nanoporous TiO2 surfaces. They have been studied using FTIR, UV-vis and XPS spectroscopy. Photovoltaic properties and IPCE (incident photon-to-current conversion efficiency) were also measured. The work includes development of the IPCE apparatus and the techique which ultimately improved the results. Theoretical DFT calculations for the vibrational frequencies of the dye Ru(dcbpy)2(NCS)2 were used and verified the FTIR spectra. A few scenarios were considered to simulate the effects of water seen in the experimental spectra. All the spectroscopic measurements showed effects due to interactions with water. These effects were not only seen as a lowering of intensity due to losses of dye molecules to the water solution. The results gave information of how the dye N719 is bonded to the TiO2 surface and electronic structure as well as efficiency of the solar cell. Shifts in the spectra due to geometry changes, interaction with new ions bonded to the surface, effects of the pH level and losses of the TBA+ ions were discussed. Strategies to control the effects of water and thereby optimise the preformance are under consideration for the future.

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Rodríguez, Pérez Ivette. « Unsteady laminar convection in cylindrical domains : numerical studies and application to solar water storage tanks ». Doctoral thesis, Universitat Politècnica de Catalunya, 2006. http://hdl.handle.net/10803/6689.

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Los dispositivos de almacenamiento de energía térmica son ampliamente usados en diversos sistemas térmicos caracterizados por un desfase temporal entre la producción de energia y su consumo, como es el caso de los sistemas de energía solar térmica. El diseño optimizado de estos equipos puede representar un considerable aumento en el rendimiento térmico de la instalación de la cual forman parte. En la línea de optimización de sistemas y equipos térmicos, en los últimos años la Mecánica de Fluidos Computacional (CFD) se ha consolidado como una herramienta básica, proporcionando a investigadores e ingenieros un método para ensayar virtualmente sus diseños, disminuyendo los costes en términos de tiempo, recursos y personal. Es en esta línea se encuentran las principales aportaciones de esta tesis, la cual tiene como principal objetivo la simulación numérica de procesos de convección laminar en régimen transitorio y dominios cilíndricos para su aplicación al estudio de los fenómenos de transferencia de calor y dinámica de fluidos que tienen lugar en los tanques de almacenamiento de energía.

Se presenta la metodología seguida para la resolución de las ecuaciones gobernantes de la transferencia de calor y dinámica de fluidos en coordenadas cilíndricas, mostrando las principales particularidades de su discretización para este tipo de geometrías y se detalla el tratamiento realizado para resolver estas singularidades dentro del código numérico. Posteriormente, se expone la metodología para la solución de flujos transitorios e incompresibles y se realiza un riguroso proceso de verificación del código y las soluciones numéricas obtenidas.

Esta metodología se aplica al estudio del comportamiento de los tanques de almacenamiento de energía estratificados. Un aspecto básico del funcionamiento de estos equipos es la calidad de la energía almacenada. Esta calidad viene determinada por el grado de estratificación térmica, en la cual influyen diferentes factores como la mezcla que ocurre debido a las corrientes de fluido que entran durante los procesos de carga y descarga térmica y también debido al intercambio de calor con el ambiente. En este sentido, en este trabajo se analiza la estratificación térmica para diferentes condiciones de trabajo y configuraciones por medio de las simulaciones numéricas multidimensionales. Para medir el grado de estratificación se han tenido en cuenta diferentes parámetros y como resultado del estudio, se propone un parámetro adimensional basado en un análisis exergético. Esta exergía adimensional ha permitido comparar el funcionamiento de los tanques en las diferentes situaciones analizadas y se ha mostrado útil para cuantificar la calidad de la energía almacenada.

Por otra parte, se estudia el comportamiento térmico de los tanques de almacenamiento durante su modo de operación estático y considerando las pérdidas de energía al ambiente. Este estudio tiene como objetivo fundamental caracterizar el proceso de enfriamiento del fluido en tanques que forman parte de sistemas solares térmicos para el rango de bajas y medianas temperaturas. Se presenta la metodología seguida para el análisis, desde la identificación de los números adimensionales que definen el problema, la formulación de un modelo zonal para la predicción del comportamiento térmico, el estudio paramétrico llevado a cabo y el posterior post-proceso de los resultados con el objetivo de proporcionar los parámetros necesarios para alimentar el modelo zonal. El modelo propuesto, junto con las correlaciones obtenidas, predicen correctamente el comportamiento del fluido, constituyendo una alternativa interesante para reproducir el proceso de enfriamiento del fluido en los tanques durante largos periodos de tiempo.
Thermal storage devices are widely used in many thermal systems and applications that are characterised by the delay between energy production and consumption, such as thermal solar systems. The improvement in their design and optimisation is a key aspect in the thermal optimisation of the system, where a good preformance of the storage tank can represent a considerable increase in the overall efficiency of the installation. In the subject of optimisation of thermal equipment, Computational Fluid Dynamics have been consolidated as an indispensable tool providing researchers and engineers with a method to test virtually their prototypes with low effort in time, personnel and resources. This thesis is focused in the numerical simulation of unsteady laminar convection in cylindrical domains and its application to the study of the heat transfer and fluid flow that take place in stratified storage tanks.

The first part of this document is devoted to present the methodology followed for the numerical resolution of the governing equation of heat and fluid flow in cylindrical coordinates. The main particularities of the discretisation of the equations in these geometries, as well as the solution procedure for incompressible and transient flow problems are also presented. Special emphasis is given to the verification of the code, the appropriateness of the discretisation adopted and the verification of the numerical solution obtained.

The second part of this thesis is focused on the study of the heat transfer and fluid flow phenomena that take place in stratified storage tanks, including the performance measures and modeling efforts of these devices. The quality of the energy stored is determined by the degree of the thermal stratification of the storage tank, which is affected by several factors such as the mixing due to the inlet streams during load and unload, the heat losses to the environment, among others. In this sense, thermal stratification analysis is carried out by means of the virtual prototyping of the tanks for different working conditions and configurations. In order to measure the performance of the tanks, different parameters are considered. The analysis led to the proposition of a new exergy-based parameter as a tool for assessing and comparing storage tanks. The usefulness of this parameter for quantifying the quality of the energy stored is also shown.

Furthermore, the thermal behaviour of storage tanks during the static mode of operation considering the heat losses to the environment is also analysed. The study is addressed to characterise the cool down of the fluid inside storage tanks for solar thermal systems in the low-to-medium temperature range. The methodology followed, from the identification of the significant non-dimensional parameters that define the problem, the formulation of a zonal prediction model, a parametric numerical study by means of detailed multidimensional CFD computations and the post-processing of the results in order to feed the global model are exposed in detail. Zonal model presented, together with the correlations given are in good agreement with the numerical results and constitute an alternative for the prediction of the long-term performance of the storage tanks during the cooling process.

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Ahmed, Iftikhar. « Synthesis and application of porphyrin-POM hybrids for photocatalytic water remediation and solar energy production ». Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112070.

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Ø
The dissertation is presented on 252 content pages which has been framed in five chapters and two annexures while the title page opens into a list of abbreviations followed by a foreword on the work. The core theme of the research work is to validate the extended photocatalytic properties of porphyrin-POM materials in evolving from UV to visible light range of solar spectrum. Which describing additional modes for synthesis of hybrid materials (i) electrostatic multilayer’s comprising of Dawson , sandwich Dawson type and preyssler,s POM in combination with free base tetracationic porphyrin [H₂TPhN(Me)₃P⁴⁺] (ii) an easy method of synthesis of two dimers with a pyridinium spacer (abbreviated 4-H₂–Zn and 3-H₂–Zn) (iii) Langmuir Schafer approach for hybrid monolayer. The prepared photoactive thin layers have been characterized by UV-visible spectroscopy and fluorescence spectroscopy for optical properties. Cyclic voltammetry for electrochemistry and ionic permeability studies. Atomic force microscopy (AFM) for surface morphology and its role in physical mechanism of reduction process and shape of nanostructures obtained. Transmission electron microscopy (TEM) has been used to interpret size and shape of dendritic silver nanoparticles obtained as photoreduction product. Although ,the ultimate goal is the photoreduction of heavy metals (Cr(VI), Hg(II), Cd(II), Pb(II) ), reduction of a simpler system like Ag⁺ ion has been chosen as a model system due to single electron simpler oxidation reduction process. A novel application of photocurrent generation from these hybrid films has been demonstrated in the fifth chapter of the manuscript as an initial studies which has enhanced the significance of all previously fabricated systems upto by many folds .The foresaid development of photovoltaic application has paved the way for future studies to enhance the photocurrent yield further by tuning the electron donor-acceptor system. Both components porphyrin and POM can be tuned with different axial substituent’s and stereo chemical properties to achieve maximum yield of solar energy as well as diversified metal nanostructure for nanoelectronics, e.g. silver dendrites for sensor applications. At the end of the manuscript, three appendices describe successively the experimental techniques used to carry out this work, the Job method used to determine the stoichiometry and formation constants of complex electrostatic and coordination, and then finally the origin or Protocols for the synthesis of various compounds used

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Nieuwoudt, Mechiel Nicolaas. « Solar heating and disinfection of water : an application for rural areas in Southern Africa / M.N. Nieuwoudt ». Thesis, North-West University, 2003. http://hdl.handle.net/10394/288.

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Life is not easy for the low-income rural population of Southern Africa. This includes those living in the informal settlements around cities. It is in part due to shortcomings in basic services such as water, sanitation and electricity. More than half of the households are without running water. One of the day-to-day problems is gathering and carting sufficient water for domestic use from communal water sources. The water is often of dubious quality, and waterborne pathogens cause a range of bacterial, viral and parasitic diseases. Children and people with compromised immunities are especially at risk. Traditional energy sources for heating this domestic water, such as firewood and charcoal, are also scarce and expensive. This, inevitably, leads to a compromise in hygienic practices, and have a negative outcome on the health of the people. A device is thus envisaged that can assist the people in transporting, disinfecting and heating their water. The use of solar energy for heating the water will reduce the dependency on traditional and conventional energy sources. Southern Africa is blessed with abundant solar insolation. As a result, solar water heating was selected to be used for this device, but it must then have the ability to store the hot water until at least in the evening. The technology and regulatory background of solar water heating were studied. An ICS type solar water heater, with insulation and glazing, was selected for implementation. The mobility of the device was modelled on the familiar wheelbarrow; therefore the device was christened as the Solar Heat Barrow, or SHB. The physical and performance requirements of the SHB were determined and specified. A study of the history and practice of water disinfection led to the realisation that solar pasteurisation, though possible in the SHB, will not reliably meet the day-to-day requirements. An additional requirement for chemical disinfection was formulated. A concept was generated for a disinfectant dispenser that could be added to the SHB where necessary. This device was named the Dispenser. It could, however, not use chlorine as disinfectant due to the chemical's sensitivity to heat degradation. A South African produced disinfectant, Steripure, was then selected for this purpose. Prototype Solar Heat Barrows, in two batches of ten and fifteen, were manufactured using representative processes. The first batch was tested for performance and conformance to requirements. It showed that the goals set were mostly fulfilled. In mid-winter, water could be heated to an average of 60°C by mid-afternoon. Water at 40°C was still available at 20:00, and this performance could easily be improved with simple human intervention. Some problems were experienced in both manufacturing and testing. It can, however, be solved with relatively straightforward development of the device. A single prototype of the Dispenser was also manufactured. It served the purpose of proving the functional principles, and a large scale manufacturing approach would be needed for further development. The manufacturing process thereof especially has to be addressed. The use of Steripure in the Dispenser, from the perspectives of both disinfection and longevity at temperature, will also have to be proven. The commercial viability and user acceptance of the Solar Heat Barrow were evaluated. A costing exercise showed that the direct production cost of units would come to approximately R 380. With the additional costs of operations, distribution and marketing, the units would have to sell for at least R 600 to be commercially viable. This would depend on a market for 60 000 units over a five year period, which was shown to be realistic. Assuming the same market, the Dispenser will have to be sold for at least R 100 to be commercially viable. Users in the rural community of Mabedlane, KwaZulu Natal, evaluated the second batch of fifteen SHB units over a two-month period. Although they were more than satisfied with the performance of the SHB, none could afford to pay more than R 100 for the product. Other surveys in the informal settlements around Pretoria indicated that a selling price of R 300 could still attract reasonable sales. It was, however, shown that a policy environment does exist, in South Africa in particular, to count on institutional support for some of the shortfall in affordability.
Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2004.

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Fendrich, Murilo Alexandre. « Solar concentration for the environment industry : photocatalytic materials and application technologies ». Doctoral thesis, Università ; degli studi di Trento, 2021. http://hdl.handle.net/11572/285695.

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This thesis presents the achievements pursued during the doctoral course. The work was carried out in the context of the project ERiCSol (Energia RInnovabile e Combustili SOLari), as part of the University of Trento strategic plan for the years 2017-2021. The project was conceived to establish an interdepartmental area to promote the challenge of developing scientific research and technological innovation to increase the competitiveness of Trento at national and international level in the areas of energy and environment. Among all the goals of the project, this work dedicates special attention to 1) development of novel materials for solar photocatalytic reactions and 2) use of renewable energy to push forward applications in water remediation. To accomplish these goals, the research brings a full collection of experimental activities regarding the employment of solar concentration for the environment industry and therefore this document is organized in 9 chapters. In chapter 1, it is presented the introduction outlining the overview of the environment industry, the employment of solar light as energy source and the general and specific objectives. Chapter 2 presents a literature review regarding the last 30 years of applications correlating the use of solar light towards wastewater purification. The chapter reviews the engineering features of solar collectors, photocatalyst materials employed and the panorama of the pollutants investigated up to the present date in solar photocatalysis, presenting comparisons between models and real wastewater approaches. Chapter 3 details the experimental techniques and characterizations employed to sustain the investigation proposed in the thesis. The first part of the chapter explains the features of parabolic dish solar concentrator designed and manufactured by the IdEA group at the physics department of the university of Trento. After, it is presented the pulsed laser deposition, a thin films fabrication technique employed to produce the photocatalysts used on water purification experiments. The second part of the chapter presents the description of the characterization techniques used to reveal the fabricated photocatalyst materials properties. Based on the review on the fundamentals of solar photocatalysis and the experimental techniques, chapters 4 and 5 present a discussion in the field of novel photocatalytic materials capable to operate under concentrated sunlight irradiation. Chapter 4 in special presents the investigation regarding the fabrication of tungsten trioxide (WO3) thin film coatings, bringing the novelty of using pulsed laser deposition as the fabrication method and the evaluation of this material in photocatalysis for the degradation of methylene blue dye model pollutant. Chapter 5 instead, presents the development on Zinc Oxide (ZnO) nanoparticles, bringing an innovative point of view on a “green-synthesis” approach and the material immobilization in film for heterogeneous photocatalysis routes. Chapters 6 and 7 discuss solar photocatalysis aiming to shift applications from model pollutants to real wastewater remediation conditions. Important comparisons are performed and discussed regarding the advantages and existing drawbacks. To fulfill this purpose, chapter 6 presents an application case of solar photocatalysis to the degradation of a surfactant-rich industrial wastewater whereas chapter 7 presents the approach focused on the remediation of organic lead contaminants present on a local water well site in the city of Trento. The last experimental approach of concentrated solar light is presented on chapter 8, dedicated to the application of concentrated sunlight towards waste biomass valorization. Conversely to the application on water previously described, this chapter presents the activity on designing, fabricating and coupling a hydrothermal reactor with concentrated sunlight using it as the driving force to promote degradation of grape seeds evolving into hydrochars with possible valorization of the carbonized material. Lastly, chapter 9 presents the conclusions and suggestions, this item expresses the final considerations on the results of the experimental investigations, advantages and limitations observed, and suggests possible actions for future works.

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Michels, Roger Nabeyama. « Avaliação de um sistema de bombeamento de água alimentado por painéis fotovoltaicos ». Universidade Estadual do Oeste do Paraná, 2007. http://repositorio.utfpr.edu.br/jspui/handle/1/429.

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A presente dissertação descreve o experimento desenvolvido com a finalidade de avaliar um sistema de bombeamento de água acionado por dois painéis fotovoltaicos instalado nas dependências da Universidade Tecnológica Federal do Paraná – UTFPR, Câmpus Medianeira, estado do Paraná, Brasil. O município está localizado no oeste paranaense com 25º17’43” Latitude sul, 54º03’38” Longitude oeste e com altitude de 500,7 metros. O sistema trabalhou em situação real de funcionamento, bombeando água a uma altura de 20 metros. Foram coletados dados de fevereiro de 2005 a novembro de 2005; utilizou-se um coletor de dados computadorizado da marca Campbell Scientific INC., o que possibilitou adquirir e armazenar os valores de irradiância no plano do painel, tensão e corrente gerada, temperatura no painel, pressão e vazão. A leitura dos dados foi realizada com freqüência de 1 hertz e armazenada a cada 1 minuto. Através de cálculos obtiveram-se os valores de potência e eficiência do sistema e a potência hidráulica. O solstício de inverno apresentou eficiência de 9,58% com bombeamento diário de 2.056,44 litros, enquanto que o solstício de verão apresentou eficiência de 9,07% com bombeamento diário de 2.377,21 litros. A maior eficiência nos dias de inverno está atrelada às menores temperaturas nestes dias se comparado aos dias de verão e o fator que provocou uma maior vazão de água bombeada nos dias de verão está ligado ao tempo de insolação solar que é maior se comparado aos dias de inverno. O total de água bombeada durante o período do experimento foi de 435.042,20 litros.
The current dissertation describes an experiment to evaluate a water pumping system activated by two photovoltaic panels installed at The Federal Technological University of Paraná – UTFPR, Medianeira Campus, in the State of Paraná, Brazil. The city of Medianeira’s latitude and longitude are 25º17’43”south and 54º03’38”west respectively, with an altitude of 500.7 meters (1,642.72 feet). The system operated in a real working situation, pumping water to a 20 meters (65.62 feet) elevation. Data were collected, from February 2005 to November 2005, by means of a computerized data collector made by Campbell Scientific Inc that made possible collecting and applying irradiance values in the panel plane, generated current and tension, panel temperature, pressure and consume. Data readings were made at a 1-hertz frequency and stored every minute. Through calculi, the system efficiency and energy values and hydraulic strength were obtained. Winter solstice showed 9.58% efficiency with daily pumping of 2,056.44 liters (543.14 gallons) whereas summer solstice confirmed 9.07% efficiency with daily pumping of 2,377.21 liters (627.86 gallons). Winter day’s highest efficiency is associated to the lowest temperature in those days compared to summer days, and the factor that prompted larger pumped water consume, during summer days, was related to solar insulation time that is longer if compared to winter days. Total water pumped during the experiment period was 435,042.20 liters (114,900.99 Gallons)

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Cruz, Jose Manuel dos Santos. « Buoyancy-driven convection in cavities with particular application to the development of a low cost solar water heating system ». Thesis, University of Bath, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389948.

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The overall aim of the research reported here was the development of a simple, low-cost passive solar heating system for operation in the Portuguese climate. The performance of this device is critically dependent on the rate of convective heat exchange across the cavity behind the heater plate. Both computational and experimental studies of the heat transfer characteristics of this new storage device, have been conducted. An experimental installation in full scale was designed and constructed to enable the measurement of local heat transfer rates. Computer simulations of the laminar flow under solar-driven conditions were made using an existing steady, threedimensional computational fluid dynamics (CFD) code based on the finite-volume method (PHOENICS Code shareware version 1.S). A boundary-fitted co-ordinate system was developed to fit the non-rectangular geometry of the cavity, that represented the water store, which provided the computational grid for the CFD code. The experimental data from the test rig was used to validate the CFD model. A solar water heating system was built to test the design under realistic weather conditions. The experimental thermal performance was evaluated in 48% while the theoretical was estimated in 51 %.

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Iordanou, Grigorios. « Flat-plate solar collectors for water heating with improved heat transfer for application in climatic conditions of the Mediterranean Region ». Thesis, Durham University, 2009. http://etheses.dur.ac.uk/174/.

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The aim of this research project is to improve the thermal performance of passive flat plate solar collectors using a novel cost effective enhanced heat transfer technique. The project work focuses on the process of energy conversion from the collector to the working fluid. This is accomplished by employing an aluminium grid placed in the channels of a collector to induce a gradient of heat capacitance. This novel technique is tested both theoretically by means of simplistic designs using Computational Fluid Dynamics (CFD) and experimentally using two unglazed collectors. One collector has the aluminium net inserted in its channels and it is tested against an identical conventional collector in order to have a direct comparison at the same time. The obtained CFD data and the experimental findings are coupled and show a good agreement. All the obtained results are validated with the literature. The results both theoretical and experimental demonstrate an enhancement in the heat transfer coefficient by 9 % resulting to an increase in the output temperature of the working fluid in the collector with the metallic insertion. Other parameters such as the Nusselt and Raleigh numbers supported these findings. Three novel expressions that correlate the Nusselt and the Rayleigh number, for different heat fluxes, were developed using data from CFD and experimental results. These correlations can be applied on any flat plate collector with an aluminium grid in its pipes, in order to predict its performance. Furthermore an existing lumped parameters model that predicts the output temperature of a collector was simplified and improved.

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Vu, Thi Thuy Duong. « TiO₂ and its derivatives : synthesis, characterization and application in H₂ production via water splitting and in bulk heterojunction solar cells ». Doctoral thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/25661.

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Dans un contexte de crise environnementale et d'épuisement des ressources énergétiques conventionnelles, le modèle énergétique obsolète fondé sur les combustibles fossiles doit être redéfini et redessiné. Malgré plusieurs types d'énergies alternatives renouvelable en développé et en cours de développé, en sachant qu'elles jouent un rôle important à moyen et long terme, l'utilisation de l'énergie solaire présente actuellement un grand intérêt aux scientifiques. La production d'hydrogène par la dissociation de l'eau et le dispositif photovoltaïque en convertit directement la lumière solaire en électricité devient plus compétitifs mais son coût ne cesse de diminuer en parallèle du progrès de la technologie. En conséquence, cette thèse concentre sur la synthèse et la modification de nanoparticules de dioxyde de titane (TiO2) et aussi parlant de la fabrication et de l'optimisation des dispositifs basés sur ces nanoparticules pour des applications photovoltaïque et de la photo-catalyse par la dissociation de l’eau. La synthèse et la modification des nanoparticules de TiO2 ont été optimisées pour contrôler la morphologie des particules, spécialement leur taille et leur forme, en utilisant différents types de surfactants. Ceci nous a permis de développer des nanoparticules de TiO2 avec différentes formes, telles que les nanosphères, les nanotiges, les nanorhombiques, et différentes tailles allant de 3 x 40 nm à 3 x 20 nm. L’effet du surfactant sur la morphologie des nanoparticules de TiO2 a été soigneusement caractérisé et analysé. La modification de la surface des nanoparticules de TiO2 ainsi développées par du sulfure de cadmium (CdS) a été optimisée dans le but de les utiliser dans les cellules solaires hybrides à hétérojonction volumique (BHJs) et aussi pour la production d’hydrogène via la dissociation de l’eau. Il a été démontré que l’efficacité de conversion de la puissance énergétique des BHJs a été augmentée de l'ordre de 17 fois en utilisant les nanotiges modifiées TiO2/CdS comparativement au nanotiges TiO2 non modifiées. Finalement, il a été démontré que la modification en surface des nanoparticules de TiO2 par du CdS et du Nickel menait à une nette amélioration dans la performance production d’hydrogène via la dissociation de l’eau. Cette réaction de dissociation présentait une stabilité.
In a context of environmental crisis and depletion of conventional energy resources, the current energy model based on fossil fuels is obsolete and needs to be redefined and redesigned. Even though, there are many different renewable alternatives developed or under developing, which are expected to take a main role in the middle and long term. The use of energy from the sun is currently attracting much attention from the scientists. For example, hydrogen generation via water splitting and photovoltaic devices that convert directly sunlight into electricity become more competitive as the cost continues to decrease with the technology advancement. Taking this into account, this thesis is focused on the synthesis and modification of titanium dioxide nanoparticles (TiO2 NPs) and the development and optimization of devices based on these nanoparticles for photovoltaic applications and photocatalyst water splitting. The synthesis of TiO2 NPs was mainly emphasized on controlling the morphologies, especially their shape and size, by using different types of capping agents. TiO2 NPs with various shapes, such as nanosphere, nanorod, nanorhombic, and various sizes from 3 x 40 nm to 3 x 20 nm were achieved. The effects of capping agent on TiO2 NPs morphologies were characterized and analyzed carefully. Based on the developed TiO2 NPs, cadmium sulfide (CdS) was deposited on the surface of TiO2 NPs, and then was optimized for the hybrid bulk heterojunction solar cells (BHJs) and photocatalytic hydrogen production via water splitting. Especially, with the use of TiO2-based nanocomposites in BHJs systems, it showed improvement of around 17 times in power efficiency conversion compared to the system used unmodified TiO2 NPs. On the other hands, with the use of a new non-noble metal-nanocomposites composed of CdS/TiO2, and Nikel clusters, the performance of the photocatalytic hydrogen production via water splitting system was enhanced and it showed that the reaction is stable up to 15h.

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Morais, Albemerc Moura de. « A difusão do acesso à água com sistemas fotovoltaicos de bombeamento no semiárido brasileiro ». reponame:Repositório Institucional da UFABC, 2015.

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Orientador: Prof. Dr. Federico Bernardino Morante Trigoso
Tese ( doutorado)- Universidade Federal do ABC. Programa de Pós-Graduação em Energia, 2015.
Várias são as soluções tecnológicas disponíveis para o acesso à água no meio rural. Dentre elas, a opção fotovoltaica apresenta-se consolidada e competitiva, podendo suprir a demanda de água em comunidades rurais dispersas. Contudo, experiências ao redor do mundo demonstram que muitos empreendimentos têm falhado por não considerarem as peculiaridades locais e os processos adequados de introdução e manutenção da nova tecnologia. Dessa forma, por meio desta pesquisa, pretendeu-se identificar os principais entraves ao sucesso de empreendimentos de abastecimento de água em regiões semiáridas baseados na tecnologia solar fotovoltaica e recomendar formas para a superação de tais entraves de acordo com boas práticas na implantação e gestão desses sistemas. Nesse contexto, foi proposto um indicativo de política pública para potencializar a difusão e inserção tecnológica da opção fotovoltaica de bombeamento no Território Vale do Rio Canindé, semiárido piauiense. Verificou-se, nesse cenário, que para possibilitar a difusão do uso da tecnologia solar fotovoltaica nesse território é necessário inicialmente o desenvolvimento de um programa de capacitação e formação de mão de obra especializada, bem como a realização de um amplo programa governamental de incentivo que possibilite o aproveitamento do leque de instituições existentes e as potencialidades produtivas locais.
Several technological solutions exist to access to provide water in rural areas. Among them, the photovoltaic option is competitive and consolidated option to supply the demand for water in remote rural communities. However, experiences around the world show that many projects have failed by not considering the local peculiarities and adequate procedures of introduction and maintenance of the new technology. Thus, through this research, we intend to identify the main barriers to the success of water supply projects in semi-arid regions based on solar photovoltaic technology, and recommend ways to overcome these barriers in accordance with best practices in the implementation and management of systems. In this context, a suggestion of public policy is proposed to enhance the dissemination and technological integration of photovoltaic pumping option in the Caninde River Valley, Piauí semiarid. It was found, in this scenario, that to enable the widespread use of photovoltaic solar technology in this area is necessary, as a first step, the development of a training program and training skill labor, as well as the implementation of a governments program of incentives that would enable the use of the range of the existing institutions and the local productive potential.

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Coetzee, René Pierré. « The development of a methodology to measure & ; verify the impact of a national solar water heating program ». Thesis, North-West University, 2010. http://hdl.handle.net/10394/9006.

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The School for Mechanical Engineering at the North-West University is home to one of South Africa's most established Measurement & Verification (M&V) teams. The team is involved with South Africa's electricity utility, Eskom, and their efforts to reduce the energy demand of the nation through Demand Side Management (DSM). One of the DSM initiatives in the residential energy sector is a National Solar Water Heating Program which encourages homeowners to purchase and install an Eskom accredited solar water heating system by means of a financial incentive. Massive financial investments have been incurred and it is only natural for stakeholders to question their return on investment. The need consequently exists to determine the impact of the National Solar Water Heating Program and establish whether it is being sustained. Before developing a methodology to measure and verify the impact of a solar water heating program an in-depth study had to be done on M&V as well as the concepts around solar water heating itself. After considering financial, time and accuracy constraints it was decided that an M&V Solar Water Heating Application along with the M&V methodology be developed. The primary aim of the application was to simulate the electrical hot water demand caused by the electrical-backup elements of the solar water heating systems and thereby avoiding the logistically and financially impossible process of measuring the electrical demand. A high-level simulation application, based on energy balances, was developed with solar water heating system types, geographical locations, weather conditions, hot water demand profiles and installation positions as inputs. The outputs of the application were the uncontrolled, simulated electrical hot water demand and were compared to the actual measured electrical hot water demand of a solar water heating system located in Cape Town. The outputs from two scenarios were compared to the measured data; one calculated with weather data from the global weather database Meteonorm, and the second calculated with the measured weather parameters acquired during the measurement period. The first scenario indicated relative accuracy with a mean bias error (MBE) and coefficient of variation of the root mean squared errors (CV (RMSE)) of 13.5% and 16.00/o respectively. The second scenario revealed improved accuracy with an MBE and CV (RMSE) of -1.1% and 5.5% respectively. The M&V Solar Water Heating Application and methodology has set the process in motion to measure and verify the impact of the National Solar Water Heating Program and will be refined as more data and information become available.
Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2010.

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Salehi, Farshid. « The Study and Practical Application of Sustainable and Energy Efficient Design and Technology for HVAC and Centralised Solar Hot Water Systems in the Al Zeina Development, Abu Dhabi, United Arab Emirates ». Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-14003.

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Telegang, Chekem Cedric. « Matériaux carbonés multifonctionnels à porosité contrôlée à partir des ressources végétales tropicales : application au traitement de l'eau par photocatalyse ». Thesis, Perpignan, 2017. http://www.theses.fr/2017PERP0026/document.

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La double fonction absorption-photodégradation des composites CA-TiO2 vis-à-vis des polluants biorécalcitrants est une alternative prometteuse pour le traitement de l’eau par voie solaire. Dans ce travail, des composites CA-TiO2 sont élaborés suivants trois méthodes simples basées sur l’utilisation des biomasses trouvées dans la sous région ensoleillée de l’Afrique subsaharienne. Les charbons actifs (CA) obtenus après pyrolyse des biomasses développent une structure poreuse qui se modifie ensuite en fonction de la voie de fixation des nanoparticules TiO2 (NPs-TiO2) pour l’obtention des composites. Parmi les trois vois de fixation du TiO2, l’imprégnation du CA avec le sol de NPs-TiO2 préformées conduit à des matériaux (CAT.SX) avec du TiO2 déposé de façon homogène à la « surface externe » du CA. Cette microtexture permet un meilleur couplage des propriétés adsorption-photodégradation, favorables aux performances de dépollution évaluées à l’échelle de laboratoire sur des solutions de phénol à 100 mg.L-1. Le réseau pores/surface spécifique est moins développé sur les composites obtenus par fixation in situ des NPs-TiO2 sur du CA imprégné de gel de TiO2 (CAT.GX), ou par pyrolyse directe de biomasse pré-imprégnée de NPs-TiO2 (CAT.SBX) ; ce qui explique les performances de dépollution moins élevées enregistrées pour ces deux dernières familles de catalyseurs. Les cinétiques d’élimination du polluant obtenues après plusieurs cycles successifs d’utilisation des catalyseurs CAT.SX ont été correctement simulées avec un modèle dont le formalisme tient compte de la double fonctionnalité des catalyseurs. Ce modèle permet d’envisager le dimensionnement d’installations solaires en condition réelle d’utilisation de ces nouveaux catalyseurs en zones fortement ensoleillée
Adsorption/photodegradation dual property of AC-TiO2 composites materials towards biorefractory pollutants is a promising issue for solar water treatment. In this work, AC-TiO2 hybrid materials have been synthesized through 03 novel routes based on the conversion of typical biomasses, abundantly found in the subsaharian African sunny areas. Biomasses pyrolysis derived activated carbon (AC) developed a porous structure which is modified differently according to the method used to fix TiO2 nanoparticules (TiO2-NPs). AC impregnated with a sol containing TiO2-NPs suspension provides the derived composite material (CAT.SX) with TiO2-NPs regularly deposited at the “external surface”, leading to a good coupling of adsorption/photodegradation activities towards phenol elimination in 100 mg.L-1 polluted water, carried out on lab scale experiments. Pore/surface area network is less developed on composites obtained after in situ fixation of TiO2-NPs on TiO2 gel impregnated AC (CAT.GX), or obtained after direct pyrolysis of TiO2-NPs impregnated biomass (CAT.SBX) – which infers lesser decontamination performances for these two latter families of catalysts. Pollutant elimination kinetics curves depicted after recycling of CAT.SX over several running water treatment was simulated with a suitable mathematical model which takes into consideration the dual functionalities of the elaborated material. The established model is a promising attempt for future dimensioning of real solar water treatment plants, operating in sunny areas with the new composite catalysts

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Zein, Waël. « Etude d'un capteur absorbant l'energie solaire par le fluide caloporteur : application au chauffage des piscines de plein-air ». Poitiers, 1986. http://www.theses.fr/1986POIT2289.

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Modelisation des transferts radiatifs pour les differents composants du capteur. Resolution numerique des equations permettant d'obtenir les lois d'evolution des performances du capteur en fonction de ces caracteristiques geometriques, des conditions radiatives et meteorologiques d'un site. Verification experimentale a l'aide d'un simulateur de rayonnement. Application envisagee, au chauffage d'une piscine en plein-air. Optimisation des conditions de fonctionnement et analyse economique du systeme de chauffage

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Touré, Ibrahima. « Calculs d'épaisseurs optiques : Évaluation des flux de diverses composantes au sol du rayonnement solaire, application capteur plan classique et capteur à renforcement de flux incident ». Nancy 1, 1987. http://www.theses.fr/1987NAN10320.

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Étude de l'estimation des flux du rayonnement solaire à partir de paramètres météorologiques et géophysiques faciles à évaluer, dans les conditions de la zone sahélienne de l'Afrique de l'ouest. Un nouveau capteur dénommé "bac solaire muni de réflecteurs" est proposé pour surmonter le handicap du faible échauffement du capteur plan classique en début de matinée, et permettant d'obtenir une température de 100**(O)C avant 10 heures

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Lujara, Nelson Kakuru. « Computer aided design of systems for solar powered water pumping by photovoltaics ». Thesis, 2012. http://hdl.handle.net/10210/6537.

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D.Ing.
Low system efficiency is a critical problem in photovoltaic (PV) applications due to low efficiency of solar cells. Despite this shortcoming, stand-alone PV systems, have proven to be economical and reliable choices in some applications such as telecommunications, vaccine refrigeration and water pumping in remote locations. In this study, CAD algorithms for the design of PV water pumping systems have been developed with the objective of maximizing the conversion efficiency from the solar irradiation to the potential energy of water by taking into account the variations in the pumping head. The study starts by developing loss models of various sub-systems in the photovoltaic dc and ac motor drive water pumping systems. Using MathCad, these models are then used in the simulation of the system. The simulation results are verified experimentally using their equivalent circuit configurations. The efficiency of the array, the pump and the motor are found to be the most critical parameters for the performance of the systems. The efficiencies of other components, such as the inverter, have also been shown to have a significant effect. The study has shown that for operation at the maximum power point, the inclusion of a maximum power tracker is necessary in a dc motor drive system but may be eliminated in PWM inverter-fed induction motor drive systems through proper matching of the system components. The study has further shown that matching of the drive system and the load with the insolation is essential, since maximum system efficiency occurs at a specific head, which varies as the insolation changes. Prior investigation of site insolation variations is therefore a critical requirement.

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Kumar, Rajan. « Design and development of solar pv fed bldc moter drives for water pumping ». Thesis, 2017. http://localhost:8080/xmlui/handle/12345678/7414.

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Kamaldeen, Mohammed Rizwan. « Sustainable Energy Source for Water Pumping at Puttalam Salt Limited ». Thesis, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-16682.

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The cost of grid based electrical and diesel sea water pumping to salt fields is one of the major cost components out of the total production cost in Puttalam Salt Limited, situated in northern part of Sri Lanka. In order to explore ways and means to improve the energy efficiency and alternative resources to meet the energy requirement a feasibility study was conducted using power system simulation software, (HOMER) and also detailed technical, environmental and financial tools. This research study is conducted to evaluate the performances and applicability and propose the most suitable sustainable renewable energy source and methodology for water pumping to salt fields instead of currently utilized grid based and fossil fueled energy supply. Preliminary results obtained by simulation software shows that direct wind mill pumping and solar PV water pumping was found to be unfeasible due to its limited pumping capacity and high investment cost. More over solar PV does not seems much feasible due to its high cost of energy (0.234 US $/kWh) compared to wind powered rivals in this type of applications. Based on comparisons of the analysis it is seen that the wind/ grid combined configuration of 04 units of AOC15/50 model (50kW manufactured by AOC Renewable Energy - Canada) wind turbine units with 150kw inverter seems to be a logical supplement for water pumping energy requirement than using grid based electricity which costs 0.201 US $/ kWh. The solution in this research affords an attractive 60% annual average renewable fraction as well as an approximate 215.8 tCO2(eq) of annual Carbon Footprint saving. Also it assures a moderate Discounted Payback Period of 6 years and 5months with a 15% of Internal Rate of Return.

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Denny, Ernest Edward. « Development of a computer program for general use in the design of solar powered water pumping systems ». Thesis, 2007. http://hdl.handle.net/10352/277.

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M. Tech. (Electrical Engineering, Faculty of Engineering) Vaal University of Technology)
Water is one of the basic necessities of life. In addition to being essential for the maintenance of life, this basic resource is a crucial requirement for combating poverty, hunger and disease in South African communities. In excess of twenty-nine percent of South African households do not have water in either their dwellings, or on site (source: 2005 RSA census data). This study documents an engineering solution to the problem of water pumping, utilising renewable energy (solar power) and readily available pumping hardware, configured via a structured design process. Resultant from the research, a software application has been developed that facilitates the design of solar (photovoltaic) powered water pumping applications. The selected design configuration of a nontracking, stand-alone, directly coupled system provides for the most robust and least complex design possible, making it imminently suitable for application in rural African conditions. Operation of the program is via a simple graphical user interface, with full and context sensitive help provided. It is tailored for use in Southern Africa and is provided with comprehensive databases of location dependant design information such as solar radiation, meteorology and magnetic declination data, together with expandable databases of pre-configured pump and solar panel hardware specification data. The program is manufacturer and component independent, with no affiliations in the choice of hardware. Design methodologies, together with a component matching strategy. Optimisation is achieved by a quantitative and efficiency 'best fit' analysis of the selected hardware components within the design context. Design output predictions are tabulated and graphed by month for a period of one year, allowing design visualisation. The application has been named 'South African Stand-alone Solar (PV) Water Pumping Design Aid', abbreviated as 'SAS-SWP' in its run-time form. The SASSWP application is illustrated in the functional overview provided in Figure 1.
VUT

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Bexiga, Maria Inês Cardoso. « Photovoltaic powered water pumping systems : design and optimization of an irrigation system ». Master's thesis, 2014. http://hdl.handle.net/10451/15897.

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Tese de mestrado integrado em Engenharia da Energia e do Ambiente, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2014
Este trabalho tem como âmbito o estudo da possibilidade do uso de energia solar fotovoltaica em sistemas de bombagem de água. Foi sugerido pela Martifer Solar o dimensionamento de um sistema de irrigação para um relvado situado na sede da empresa, em Oliveira de Frades, Portugal. A área total do relvado é 16,119m2. Inicialmente foi feito o estado da arte, onde foram discutidas as várias aplicações destes sistemas e as suas vantagens. De seguida, é descrita uma metodologia de dimensionamento, servindo como um guia para dimensionar e otimizar um sistema solar de bombagem de água. Para o dimensionamento foi abordado um método apresentado em Firatoglu et al. [1]. Primeiro foi estudada a quantidade de água necessária para a irrigação. Por se tratar de um relvado, a quantidade diária de água necessária varia ao longo dos meses desde 15m3 até 80m3. Depois, foi estudado o recurso solar para o local. Foi logo concluído que a variação da quantidade de água necessária varia de forma semelhante com a radiação solar disponível. Através do estudo de parâmetros dos vários componentes, foi feita uma correspondência entre os módulos fotovoltaicos e o motor/bomba. Foram calculadas curvas de potência máxima e curvas de pontos de equilíbrio. O principal objetivo é modelar, usando o Matlab. as duas de forma a ficaram o mais próximas possível, sem o uso de qualquer controlador eletrónico. Após o estudo de várias configurações ficou concluído que o sistema seria constituído por 14 módulos fotovoltaicos(2S×7P, com um motor com os parâmetros Kv=0.18 V/rpm e Ra=0.50Ω e com tanques de armazenamento de água. A quantidade de água necessária fica assegurada ao longo de todo o ano.
This work has the objective of studying the possible application of photovoltaic solar energy to supply water pump systems. It was suggested by Martifer Solar to size an irrigation photovoltaic water pumping system. This system is studied for the location of the headquarters of the company, in Oliveira de Frades, Portugal. The total area to irrigate was 16,119 m2. A state-of-the art was made first, where advantages and different applications of these systems were presented. After, the methodology is described as a guide to sizing and optimize solar water pumping systems. For that sizing, a multi-step method was used presented in Firatoglu et al. [1]. First, water demand was studied. Because it is a grass field, values of water daily demand change from 15m3 to 80m3, depending on the month. After, average data from solar resource was studied. The first conclusion to achieve was that water demand changes seasonally in a similar way as solar radiation available. A match between PV array and motor/pump assembly was made, through the study of manufacturer’s data of the different components. Curves from maximum power point and equilibrium operation point were calculated. The main goal is to match as much as possible both curves, with no use of any electronic controller. The modulation of the system was made using Matlab. After the study of several configurations, it was concluded that the system would have 14 PV panels, (2S×7P) with a DC motor with Kv=0.18 V/rpm and Ra=0.50Ω and storage water tanks. It is assured that water demand is fulfilled throughout the year.

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Cheng, Pei chia, et 程培嘉. « The Application of Fuzzy Control on Rain Water Pumping Station Monitoring System ». Thesis, 2008. http://ndltd.ncl.edu.tw/handle/39545989550577730983.

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碩士
國立臺灣科技大學
自動化及控制研究所
96
The rain-water pumping station is one of the most important parts of city flooding preventing system. The method of conventional rain-water pumping station is called fixed water level control, in which each pump start and stop operation depend on the preset water level of pumping station basin. Since the inflow, the rain-water reaching time and the water level of pumping station are changing rapidly with respect to different rainfall intensity during the typhoon or storm period, operators need to adjust the control situation manually based on their actual experience. In order to improve the pump running efficiency, develop a better control method is a very important topic. In this thesis, the fuzzy control theory is employed to design an appropriate control method for a rain-water pumping station in Taipei city. The actual operation records and hydrology data of new Chang-an pumping station in recent years are chosen to simulate and analyze the control performance. The performance of fuzzy control method is compared with that of the conventional control method based on the following aspects, i.e., the peak water level of pumping station basin, the times of pumps on/off , and the mean water level of pumping station basin. Based on the practical hydrology data simulation results, the proposed fuzzy control and fuzzy slide mode control methods can operate the rain-water pumping station pumps effectively and safety. It should be helpful for decreasing the possibility of flooding damage during typhoon or storm period.

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Hauat-Elias, Miguel Jorge. « Solar powered water pump improvements ». 1988. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1988_355_sip1_w.pdf&type=application/pdf.

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Shieh, Jhy-Jer. « Reduction of water contamination in a vacuum load lock during pumping from atmosphere ». 1999. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1990_463_sip1_w.pdf&type=application/pdf.

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Huang, Hshien-Chang, et 黃顯長. « Application of Project Management on Engineering : A Case Study of the Construction of Water Pumping Station ». Thesis, 2014. http://ndltd.ncl.edu.tw/handle/9we2wu.

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碩士
健行科技大學
經營管理研究所
102
Water pumping station is one of important facilities for residential water supply. How to complete the construction of facility in the scheduled time is a critical issue. The utilization of experiential data, such as case study and the management standard published by Public Construction Commission, to establish management modelling is widely applied in traditional practice. However, this modelling process of management mode lacks standard operation procedure. The traditional procedure is the sequence of project arrangement stage, master planning stage, design stage, tender awarding stage, construction stage, and acceptance stage. The management of each stage without uniform standard causes unrelated to other stages. The executive organization of each stage accomplishes tasks without feedback to the system of Project Management the Body of Knowledge, PMBOK. This study demonstrates the relationship of project execution and PMBOK system. This study also establishes management modelling to coordinate executive organization for raising the quality of project management.

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Thèses sur le sujet « SOLAR WATER PUMPING APPLICATION »

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