5.3. Scenario 2 – continuous 30 minutes forward
This is the scenario that is currently being proposed in Turkey. In this scenario, the clock is shifted forward by 30 minutes throughout the year with no DST. In other words, there is no summer or winter time practice. As a result, Turkey stays in the GMT+2.5 time zone throughout the year.
In Istanbul, in December and January, the Sun rises at 7:50 on average, creating approximately 50 minutes of morning darkness every day. When compared to the status quo, there will be more electricity demand for 30 minutes in the morning, which will be compensated in the evening. Additionally, the peak electricity demand in the evening will be shifted to the morning.
In February and November, the average sunrise time is approximately 7:20, leading to a 20-minute increased electricity consumption. However, as the Sun will also set 30 minutes later, this consumption will be well compensated for.
In March, there will be no darkness in the mornings, and an extra 30-minute period of energy conservation will be possible in the evenings as darkness will fall 30 minutes later.
For 7 months between April and October, it will be dark 30 minutes earlier in the evening, which will bring an increased demand for electricity throughout these 7 months. Despite the 30-minute electrical lighting savings made in the winter, these savings will be paid back due to the 30-minute increase in the summer. Relative error will be 7.67%.
In Erzurum, on the other hand, morning darkness will not occur in any month due to moving the clocks 30 minutes forward continuously. For 5 months between November and March, when forward time will not be used, sunset will occur 30 minutes late and thus save 30 minutes of electricity. However, in contrast to the status quo, the Sun will set 30 minutes earlier between April and October and electricity demand will rise by 30 minutes for 7 months. The savings made during the winter will thus be paid back in the summer. Relative error will be 10.78%.
5.4. Scenario 3 – continuous 30 minutes forward with single DST from April to October
This option has been designed to offset the summer disadvantages in Scenario 2 (continuous 30 minutes forward). According to this scenario, the time is shifted forward by 30 minutes as in Scenario 2 and DST takes effect on the same dates (from April to October) as in the status quo. Therefore, Turkey stays in the GMT+2.5 time zone in winter and in the GMT+3.5 time zone during DST months. The starting and ending dates of DST remains the same as in the EU countries.
Possible gains and losses for Istanbul between the months of November and March were discussed in Scenario 2. When compared to the status quo, daylight will be used 30 minutes more from April to October. When compared to Scenario 2, daylight will be used 1 hour more from April to October, which would prevent the summer losses in Scenario 2. Relative error is reduced to 4.67%, compared to the 4.99% of the status quo.
There is no daylight loss problem mentioned for Erzurum between November-March. However, in Scenario 2, a 30-minute loss occurs between April and October. In this third scenario, not only will this 30-minute loss be eliminated, but also there will be an additional 30-minute daylight gain. Relative error is reduced to 6.48%, compared to the 10.25% of the status quo and the 10.78% of scenario 2.
5.5. Scenario 4 – continuous DST with double DST from April to October
This scenario presumes that clocks are not moved backward but forward between April and October. Turkey will be in the GMT+3 time zone during winter months of November to March and in the GMT+4 time zone from April to October. The clocks will be the same as in Scenario 1 in winter months. Therefore, Turkey will be 1 hour ahead of the status quo throughout the year in this scenario.
The advantages and disadvantages of continuous DST for Istanbul between November and March were discussed in Scenario 1. There will be 20 minutes darkness in April, 11 minutes in August, 40 minutes in September, and 1 hour 12 minutes in October. Sunset in the summer will be at 21:30 on average, which may have an adverse effect on people resting throughout the evening. Relative error is increased to 6.11%, compared to the 4.67% of Scenario 3.
The application between November and March will be the same as in Scenario 1. Therefore, advantages and disadvantages will be similar. When the time between April and October is considered, there will be morning darkness only in October for 22 minutes. Sunset times will range between 19:26 (September) and 20:48 (June), which would not lead to any problems, as current sunset times are similar in western cities. Relative error will be 4.21%.
5.6. Scenario 5 – maintaining the status quo by changing DST dates
In this scenario, winter and summer time shifts will be the same as in the status quo. The only difference between this alternative and the status quo is the different start and e