There is little to say on the first day. I gave myself a full smartphone and a full power bank. In the car on the way to the university, the first big power draw: 45 minutes of audiobook. Charging in the office as long as there was still light, and the same on the way back. 17:20 and 100%. You can't see it so well on the power bank, but at least 3 of 4 little lights are lit … so the third Advent is still alive. Tomorrow it gets more exciting, when the power bank doesn't start full.