Abstract
M.Sc.
The Christmas and Easter holiday periods have a large influence on electricity load.
Forecasting the load for these periods is difficult since the changes in the load patterns
are sudden and substantial. Furthermore, the effects of these periods on the load
patterns are dependent on the timing of Easter and the weekday composition of
Christmas, which change from year to year. A strategy is presented to forecast the
hourly electricity load for these holiday periods as well as the periods shortly
afterward. This strategy is based on a general fixed structure ARIMA model
developed to forecast the hourly load for periods with no unusual load activity. The
general model is supplemented by information on the two holiday periods, extracted
from the corresponding periods in historical years by means of growth independent
scale factors. A model for forecasting the total weekly load is also presented. This
model makes use of intervention techniques to account for the changes in the load due
to the Christmas and Easter holiday periods. The forecasting methodologies are all
geared towards practical application and are suitable for on-line implementation.