Fig. 4 shows hourly average electricity use in October 2007 for the last four weeks before the end of DST, and in November 2007 for the first four weeks after DST ends [29]. In this transition time, peak demand shifted two hours from 20:00 to 18:00 and increased 3476.0 MW (15%). Total daily increase was 45,208.0 MWh (9.5%) on average. This increase was influenced heavily by weather conditions. While the average temperature was 15.9 C° in October 2007, it decreased to 8.3 C° in November 2007. On the other hand, the average temperature was 7.6 C° in March 2007, and increased marginally up to 9.8 C° in April 2007 [30]. Even though the total difference cannot be explained only by the change in weather, it is undoubtedly one of the most important reasons for the increase in electricity use. Other factors such as the monthly change in electricity use in industry may also affect the situation. What is clear is that peak demand changes notably.