ESTIMATION AND ANALYSIS OF TOTAL SOLAR RADIATION FOR SELECTED EIGHTEEN NIGERIAN CITIES USING MEASURED METEOROLOGICAL DATA (2000 – 2010)

SOURCE:

Faculty: Physical Sciences
Department: Physics And Industrial Physics

CONTRIBUTORS:

ELEKALACHI C. I
NWOKOYE, A.O.C

ABSTRACT:

Global solar radiation is an important parameter necessary for most ecological models
and serves as input for different photovoltaic conversion systems. Hence it is of
economic importance to renewable energy alternative. In this study, we have employed
the linear regression model of Angstrom (1924) and Page (1964) for these analyses to
correlate the global solar radiation data with relative sunshine duration, relative
humidity and maximum temperature for 3 cities (sites) in each of the six geopolitical
zones in Nigeria, which gives a total of 18 sites. Other multiple linear regression models
were obtained to check the correlation of global solar radiation with sunshine duration
combined with other meteorological parameters which include maximum temperature
and relative humidity. These meteorological parameters used for this work were
obtained from the archives of National Aeronautics and Space Administration (NASA)
for the time period of 11 years from 2000 to 2010. The results obtained were statistically
tested using four statistical error indicators; Mean Bias Error (MBE), Root Mean Square
Error, (RMSE), Mean Percentage Error (MPE) and t-stat to establish the validity of the
results. The analyses show that there is close correlation between the calculated mean
global solar radiation and the estimated global solar radiation using our established
models, though some models correlate better than others. The best empirical equation
for each of the sites was evaluated based on the values of the t – stat. 𝐻3
is the best
model for Awka with t – stat value of 0.050. 𝐻1
is the best model for Enugu with t –
stat value of 0.045. 𝐻5
is the best model for Owerri with t – stat value of 4.692. 𝐻3
is
the best model for Calabar with t – stat value of 0.0327. 𝐻3
is the best model for Port –
Harcourt with t – stat value of 0.0830. 𝐻1
is the best model for Asaba with t – stat value
of 0.0126. 𝐻5
is the best models for Lagos with t – stat value of 0.00259. 𝐻5
is the best
model for Akure with t – stat value of 0.0232. 𝐻5
is the best model for Ado – Ekiti with
t – stat value of 01.166. 𝐻5
is the best model for Gombe with t – stat value of 0.0361,
𝐻1
is the best model for Yola with t – stat value of 0.056. 𝐻3
is the best model for
Maiduguri with t – stat value of 0.0359. 𝐻1
is the best model for Abuja with t – stat
value of 0.0882. 𝐻1
is the best model for Minna with t – stat value of 0.281. 𝐻3
is the
best model for Ilorin with t – stat value of 0.00148. 𝐻3
is the best model for Gusau with
t – stat value of 0.0184. 𝐻2
is the best model for Kano with t – stat value of 0.0112. 𝐻5 is the best model for Birnin – Kebbi with t – stat value of 0.0338.