nostr:npub1gajvsj4vhehzjtpq9sax45j49qa623vtl6fu6djjrjzm05w48l8srt78dz Try the Logitech Solar Keyboard K760. I've had one for more than 10 years now. Charges directly through solar or ambient light. I just keep it out in the light and it's always charged.

https://www.amazon.com/Logitech-Wireless-Solar-Kebyoard-iPhone/dp/B007VL8Y2C