So when you set up 5 rankeds today, they will be scheduled with the daily update, so for the next day. The energy drain takes action with the daily update the next day.
Or in other words, the update checks how many games you have played over the day and calculateds the energy drain of that.
So you probably will notice the expect less energy drain with today's daily update, since you just reduced the games for today, but not yesterday.
Does that sound like it makes sense?