

Start by defining your available power. How many watt-hours can you generate? A small 100W solar panel can provide an average of 400Wh of energy per day in the winter. That’s more than enough to run a 10-inch tablet 24/7 and LED lighting at night. I’ve seen 360W solar panels for under $100 on the used market. That’s a couple of KWh a day. Even a 100W bicycle generator and a 30 minute workout would power a tablet for 8 hours.
If power consumption is that big of a factor, perhaps separate devices for video, music, and reading would be beneficial. A dedicated music player can consume less than a watt. An e-paper reader requires fractions of a watt.
I have a folding 100W panel, a 30Ah 12V LiFePO4 battery, and a charge controller that I use while car camping. It keeps all the electronics running for a group of 4 without relying on a noisy generator. The battery is big enough to compensate for a couple of rainy days.
My backpacking setup is a 15W panel and a 30Wh battery. That kept my phone and flashlight charged for 2 weeks on the Pacific Crest Trail.
Not as tough as it seems. People routinely memorize much more in shorter periods. Try learning the complete Kanji (Asian Pictograms) or heiroglyphics. It’s not inconceivable to memorize 10,000 random words. Think of how many songs you can recite the lyrics to. I learned Billy Joel’s, “We Didn’t Start the Fire” in a day. That’s pretty much what this challenge is about - a random list of words.