Another forecasting approach was the utilization of the ANN method to derive a prediction model.
The development of ANN models was based on studying the relationship between input variables and
output variables. For application in forecasting, Hsu and Chen [8] assessed the performance of ANN
approach (based on three inputs, i.e., GDP, population and temperature) to forecast the regional peak
load in Taiwan. The historical data was the annual power load in each region from 1981 to 2000 and
the performance of ANN method was compared with the regression method. The study showed that
the error of ANN model was significantly lower than that of the regression model. Moreover, Catalao,
Mariano, Mendes and Ferreira [9] successfully applied the ANN for forecasting next-week prices in the electricity market of Spain and State of California short-term electricity prices. The hourly price
data of 42 days prior to the week whose prices were forecasted was used as the historical data. The
error criterion (MAPE) of the ANN model was compared with the one from ARIMA model and the
results indicated that the ANN outperformed the ARIMA model. Similarly, Bakirtzis, Petridis, Klartzis
and Alexladis [10] developed an artificial neural network to forecast daily loads with a lead time of
one to seven days. The seasonality effect from high energy usage on holidays was included in the
model by utilizing the seasonal training (training the ANN with the historical holiday data).
The multiple linear regression method is still an interesting forecasting option because