Or you might be able to use a solar powered USB battery pack. They're pretty cheap now. I'm not sure quite how much power the panels produce but I'd imagine it should be enough to keep WiFi up for 30 seconds a day.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Or you might be able to use a solar powered USB battery pack. They're pretty cheap now. I'm not sure quite how much power the panels produce but I'd imagine it should be enough to keep WiFi up for 30 seconds a day.