Abstract:
In this paper, six selected empirical models
were used to estimate the hourly global solar radiation
from the daily global radiation in Kuala Terengganu on the
east coast of Malaysia. The purpose is to determine the
most accurate models to be used for estimating the hourly
global solar radiation. The measured hourly global solar
radiation data used for the validation of selected models
were obtained from the Malaysian Meteorology
Department and University Malaysia Terengganu
Renewable Energy Station for the period of 2004–2008. In
order to indicate the performance of the models, the
statistical test methods of the normalized mean bias error,
normalized root mean square error, correlation coefficient
and t- statistical test were used. The hourly global solar
radiation values were calculated by using six models and
the results were compared with corresponding measured
data. All the models fit the data adequately and can be used
to estimate the hourly global solar radiation. This study
finds that the Collares-Pereira and Rabl model performed
better than other models. Therefore the Collares-Pereira
and Rabl model is recommended to estimate the hourly
global radiations for Kuala Terengganu and elsewhere with
similar climatic conditions.
