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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Improving Photovoltaic Panel Efficiency by Cooling Water Circulation

Joseph, Jyothis 12 1900 (has links)
This thesis aims to increase photovoltaic (PV) panel power efficiency by employing a cooling system based on water circulation, which represents an improved version of water flow based active cooling systems. Theoretical calculations involved finding the heat produced by the PV panel and the circulation water flow required to remove this heat. A data logger and a cooling system for a test panel of 20W was designed and employed to study the relationship between the PV panel surface temperature and its output power. This logging and cooling system includes an Arduino microcontroller extended with a data logging shield, temperature sensing probes, current sensors, and a DC water pump. Real-time measurements were logged every minute for one or two day periods under various irradiance and air temperature conditions. For these experiments, a load resistance was chosen to operate the test panel at its maximum power point. Results indicate that the cooling system can yield an improvement of 10% in power production. Based on the observations from the test panel experiments, a cooling system was devised for a PV panel array of 640 W equipped with a commercial charge controller. The test data logger was repurposed for this larger system. An identical PV array was left uncooled and monitored simultaneously to compare the effect of cooling, demonstrating that the cooled array provided up to an extra 132W or 20% of maximum power for sunny weather conditions. Future expansion possibilities of the project include automated water level monitoring system and water filtration systems.
72

Development of an Efficient Solar Powered Unmanned Aerial Vehicle with an Onboard Solar Tracker

Tegeder, Troy Dixon 10 March 2007 (has links) (PDF)
Methods were developed for the design of a solar powered UAV capable of tracking the sun to achieve maximum solar energy capture. A single-axis solar tracking system was designed and constructed. This system autonomously rotated an onboard solar panel to find the angle of maximum solar irradiance while the UAV was airborne. A microcontroller was programmed and implemented to control the solar tracking system. A solar panel and an efficient airframe capable of housing the solar tracking system was designed and constructed. Each of these subsystems was tested individually with either ground or flight tests. Ultimately, the final assembled system was tested. These tests were used to determine where and when a UAV with an onboard solar tracker would be advantageous over a conventional solar powered UAV with PV cells statically fixed to its wings. The final UAV had a wingspan of 3.2 meters, a length of 2.6 meters, and weighed 4.1 kilograms. Its solar panel provided a maximum power output of 37.7 watts. The predicted system performance, airframe drag, and system power requirements were validated with a battery powered flight test. The UAV's analytical model predicted the drag to be 41% lower than the actual drag found from flight testing. Full system functionality was verified with a solar powered flight test. The results and analysis of the system tests are presented in this thesis. The net energy increase from the solar tracking UAV over a conventional solar powered UAV for the duration of a day is dependent on season and geographical location. The solar tracking UAV that was developed was found to have a maximum net energy gain of 34.5% over a conventional solar powered version of the UAV. The minimum net energy gain of the solar tracking UAV was found to be 0.8%.
73

Design pouliční svítilny s nezávislým napájením. / Off-grid street lamp design.

Hampl, Petr January 2009 (has links)
Oblast problémů, ze kterých konkrétní téma projektu vychází, zahrnuje současnou globální transformaci zdrojů energie a jejich dodávek se zvláštní pozorností na obnovitelné zdroje energie. Důraz je kladen zejména na hodnoty jež přináší produkt určený k užívání ve veřejných prostorách. Autorovým zadáním bylo navrhnout osvětlovací jednotku nezávislou na vnějším zdroji napájení. Cílem návrhu je přehodnotit způsob, jakým jsou dnes technologie využívání sluneční a větrné energie běžně používány, a navrhnout řešení přinášející nové vlastnosti a užitné hodnoty pro přímého uživatele i celou společnost. Autor přináší návrh produktu jenž je reakcí na současné globální hrozby a příležitosti. Výsledkem projektu je návrh pouliční lampy kombinující fotovoltaický článek a větrnou turbínu s cílem získat elektrickou energii jež je dočasně akumulována a následně dodávána svítidlu. V návrhu je kladen důraz na požadavky ergonomie a estetickou hodnotu produktu. Navržené řešení znamená finanční přínos z hlediska šetření neobnovitelnými zdroji energie a případnými finančními výhodami pro investora plynoucími z provozování veřejného osvětlení. Pouliční lampa nezávislá na vnějším zdroji napájení má navíc menší negativní dopad na životní prostředí a představuje technologie využívání větrné a solární energie v přívětivé a nerušivé podobě.
74

Aquapark Brno / Water park Brno

Modlitba, Zdeněk January 2019 (has links)
The topic of the diploma thesis is a revitalization of a historically valuable area Za Lužánkami as a center for sport and leisure time, but also sets an urbanism concept and development of a neighborhood housing area. A complex architectural study solves an extension of an existing Lužánky city swimming pool in Brno. The main idea is a simple form of the new building, easy walkthrough the territory, creating an enjoyable public space and an extension of the existing greenery. The new water park is designed as a two-storey, rectangular object, connected with an existing swimming pool. Inside you can find a 25m swimming pool, a plenty of relaxing pools, wellness, café and offices. The inner part is also connected with an outdoor pools with a big slide, terrace for sunbathing and a playground. The overall proposal offers an exploitng the potential of this area as a solution to the current city deficits, such as parking lots, housing and especially the sport facilities near the Brno city center.
75

Koncept nabíjecí stanice s možností off-grid provozu pro elektrokola / Concept of Charging Stations with off-grid Operation for Electric Bicycles

Leitman, Valentín January 2017 (has links)
This thesis deals with charging stations for electric bicycles powered by renewable energy. The aim of this work is to make a proposal for the hybrid charging stations for electric bicycles, which will work independently and, if necessary, will be backed up by a network. In this thesis is entered theoretical information on the issue of electric bicycles, the batteries, charging stations, the connectors of chargers, and photovoltaic systems. The practical part of this thesis is the basic design of the charging station and its design of the mathematical model of the individual parts in Simulink program, which are linked to the actual design of the charging station. In conclusion, this thesis deals with energy and economic analysis of the proposed system, therein included various methods of assessing investment recommendations of appropriate processing methods and overall assessment of the subject.

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