Abstract:
Monthly average daily global solar radiation data are
essential in the design and study of solar energy
conversion devices. In this regard, different empirical
models based on Angstrom-Prescott model were selected
to estimate the monthly average daily global solar
radiation, H, on a horizontal surface for Terengganu state
using only the sunshine duration. The hourly solar
radiation data measured at Kuala Terengganu station
during the period (2004–2007) were used to calculate the
monthly mean values of H using selected models. The
selected models were compared on the basis of the
statistical error tests as the mean bias error, the mean
percentage error, the root mean square error, Nash–
Sutcliffe equation, correlation coefficient and the t-test.
Based on the statistical results a new linear model H/H
o=
0.2207 + 0.5249 (n/N) based on modified Angstrom
model is extremely recommended to estimate monthly
average daily global solar radiation for Terengganu state
areas and in elsewhere with similar climatic conditions
areas where the radiation data is missing or unavailable.
The present work will help to advance the state of
knowledge of global solar radiation to the point where it
has applications in the estimation of monthly average
daily global solar radiation.
