Abstract:
This research aimed to compare three methods of forecasting wind speed: Box-Jenkins method, Winters additive exponential smoothing method, and Winters multiplicative exponential smoothing method. Time series of hourly wind speed at an altitude of 120 meters in Mukdahan province were gathered from research center in energy and environment, Thaksin university during 1 June to 1 July 2015 of 721 observations. The criteria of the lowest mean absolute percentage error (MAPE) and root mean squared error (RMSE) were used for comparing the accuracy of the forecasting model. Research findings indicated that for all forecasting methods that were studied, the most accurate method was the Box-Jenkins method. This forecasting method was 4.9216 percent forecasting error (MAPE = 4.9216) or was forecasting error of 0.5 meter/second (RMSE = 0.5). The comparison of the accuracy of the forecasting model for both criteria provided the same result. Therefore, it made more reliable that the Box-Jenkins method was the most suitable method for this time series.