Electricity:

I go by the maxim that being rich is having more that what you need. Which is why I navigate with a smart watch. My estimate is that I "need" 1Wh/day. Next to nothing...

In my experience, dynohubs didn't fare well when flying. My inexperience. Two years in a row the connexions were damaged in transit. And when the charger did work, results were often surprising. A dynohub starts generating at, say, 8mph (12kph). This is slow, but if your day is a long uphill, you may well be below that critical value for most of the day (like the day we "climbed" Mt Fuji. Etc. So in my book, dynohubs are for commuters, more than for tourers.

Solar... Last year didn't work because the panel was too small. This year (7W) it did. Keep in mind that I need very very little. I don't think that you can reliably navigate with a phone. And the last touring computer I've used was consuming just as much, so that wouldn't work either.