Abstract:
A method of simulating the performance and optimal size of photovoltaic (PV) systems
based on the observed time series of some heliophysical variables was developed and
explored in this research. The data used were the sunshine duration and solar radiation
intensity for years 1990 to 2004 for eleven Nigerian stations obtained from the archives
of the Nigeria Meteorological Agency NIMET. Appropriate programs were developed
using MatlabR code to model the performance of a photovoltaic system and the optimal
values of photovoltaic area. Input parameters which were estimated from the obtained
heliophysical variables and used in the simulation were clearness index and total
radiation on an inclined surface. The output parameters include utilizability, monthly average
fraction of the load covered by the photovoltaic system with battery storage,
monthly-average fraction of the load covered by the photovoltaic system without battery
storage, monthly-average of uncovered load fraction of the photovoltaic system, area of
the panel, optimal area of the panel, optimal total cost of the panel and the increase in the
solar load fraction due to storage. Solar load fraction with storage ranges between 27.2%
and 28.2% conversion efficiency of solar cell. Maximum incident solar radiation onto the
photovoltaic array is obtainable in dry season which lead to better performance of
photovoltaic electrical output and lower values of utilizability either when the excess
solar load fractions are being stored or not. The average cost of the optimized plant,
capable of supplying 15 kW, is #809,800. A comparison of the optimized cost with
PHCN current charge indicated that after one year and six months, the user of the plant
wi!!jJecome a free user of electricity! The optimized photovoltaic plant is short term cost
-e-f-.f~ective and much cheaper than the non - optimized plant.
