Selected Students Project Abstracts 2013/2014 academic year
ALI OSUNDWA (I20/1545/2010)
SHADING ANALYSIS FOR A MULTI-MODULE INSTALLED PV SYSTEM: Case of Jamhuri Agroforestry and Energy Center
There is great need for solar energy industries, companies or home consumers to survey for suitable site for installation solar arrays, site that will receive maximum sunlight for maximum production of power throughout the year.
In this project work, solar pathfinder was used to survey shading analysis on multi-module PV system at the roof of Jamhuri energy station building in Dagoret corner, Nairobi. Reflected images viewed using the solar pathfinder was captured for every module using digital camera.
Azimuth angle, tilt/orientation of the modules, latitude/longitude at Jamhuri were noted and then inputted in PV studio software. The Captured images were uploaded in the software, traced and then created the report. The Software uses PVwatts calculator from NREL to make mathematical precision for accurate shading assessment to give the output. Such output parameters include: unshaded percentage of the site, actual shaded/unshaded AC energy, actual solar radiation and PV solar cost of saving.
Trees shade greatly affected the power output, and in addition, birds drooping and dusts also contributed in drop of the output. Recommendation of the suitable site was later presented.
Peter Brian Mambo (I20/1605/2010)
Communication Via Software
A few hundred years ago, when kingdoms and empires existed such as The Roman Empire, Kingdom of Macedonia(led by Alexander the Great) e.t.c,communication used to be simplistic. This means, the manner of message transfer and delivery from one place to another was simple, involving a messenger, the message and the recipient. For example, in the Macedonian setup, if Alexander wanted to pass a message to one of his subjects, all he did was to summon a messenger and give him the message. The messenger would run al the way to the destination of the recipient and deliver the message and in that manner, the news would be delivered. The question was, what if the recipient lived in Southern Australia while the sender was in Northern Canada?
This gave rise to internet communication in form of email, world wide web, packet data,teleconferencing, e.t.c. However,the internet is based on the concept of networking, since from its definition, its just a collection of interconnected networks.
Presently however, the mode of communication has been advanced to include data transfer through infrared,Bluetooth,wi-fi and other FTPs .
Maina Stephen Wangara (120/1638/2010)
RAMAN STUDIES ON EFFECTS OF HEAT ON TIO2/NB2O5 COMPOSITE THIN FILMS DEPOSITED BY ELECTROPHORETIC DEPOSITION
Composite materials sometimes exhibit rather unusual characteristics that are not prominent in pure materials and they could lead to novel applications and enhancements in existing devices. TiO2/Nb2O5 composite thin films were prepared using Electrophoretic deposition on a FTO glass substrate at a constant voltage for a period of 90seconds. The films were annealed for a period varying between 1 and 6hrs at a constant temperature of 4000C after deposition. The films were then characterized by use of Raman spectroscopy. The results showed that titanium dioxide was more present on the films with the Raman spectra of its anatase phase being picked throughout the whole experiment. From the data it was observed the film annealed for 3 hours produced the highest Raman intensity peaks for the anatase phase thus making known that it is the ideal time for annealing since that’s when it is most stable and has highest crystallinity.
NGUGI ESTHER WANJIRU (I20/1583/2010)
STUDY OF SYSTEM PERFORMANCE FOR AN INSTALLED PV-GEN SET HYBRID SYSTEM: A CASE STUDY OF MPALA RESEARCH CENTER, NANYUKI
The number of PV and PV-hybrid systems installed worldwide has been experiencing a significant increase during the recent years. Essentially, most of the isolated places and villages in the rural area of our country KENYA have adopted the PV-hybrid systems. Reason being they have not been incorporated not the Rural Electrification Programme (REP) by the government. This is because some of the places are sparsely populated hence low energy demand and underinvestment in infrastructure has hindered the grid power from reaching there. This research analyses the long term performance of a selected site known as Mpala Research Center located in (longitude, latitude) 40 kms off Nanyuki town on the northern side of the equator. This pace was taken as a case study sample to represent many other systems that have adopted the PV-gen set hybrid systems in our rural areas. The study established great energy losses in unsized PV-gen set. It also presents some calculations for the yield of the system and load audit as well as recommendation for improvement of the system and close examination to the system to establish the necessary changes to help correct the sizing errors.
KIRAGU ALEXANDER NDIRANGU (I20/1609/2010)
DEVELOPMENT OF A SOLAR CELL CHARACTERIZATION LABORATORY EXPERIMENT FOR UNDERGRADUATE STUDENTS
A solar cell characterization technique experiment has been developed for undergraduate students in the Department of Physics, University of Nairobi. The technique has been experimentally tested and the test data developed to prove the reliability of the technique. The data was collected over two different days and at different times. The data obtained is very consistent and agrees well with the manufacturer’s data. The technique is recommended for first degree students.