Abstract: Demand planning for electricity consumption is a key success factor for the
development of any countries. However, this can only be achieved if the demand is
forecasted accurately. In this research, different forecasting methods—autoregressive
integrated moving average (ARIMA), artificial neural network (ANN) and multiple linear
regression (MLR)—were utilized to formulate prediction models of the electricity demand
in Thailand. The objective was to compare the performance of these three approaches and
the empirical data used in this study was the historical data regarding the electricity
demand (population, gross domestic product: GDP, stock index, revenue from exporting
industrial products and electricity consumption) in Thailand from 1986 to 2010. The
results showed that the ANN model reduced the mean absolute percentage error (MAPE)
to 0.996%, while those of ARIMA and MLR were 2.80981 and 3.2604527%, respectively.
Based on these error measures, the results indicated that the ANN approach outperformed
the ARIMA and MLR methods in this scenario. However, the paired test indicated that
there was no significant difference among these methods at α = 0.05. According to the
principle of parsimony, the ARIMA and MLR models might be preferable to the ANN one
because of their simple structure and competitive performance