DFM8001 Energy Harvesting Module kit can collect indoor mechanical, thermal, solar, and radio frequency energy for IoT devices. It features easy assembly, dynamic MPPT tracking, integrated charge and discharge management, and dual-channel voltage stabiliz
I'm not sure how much power those different modules are capable of gathering, but based on this video from GreatScott! that tests similar-ish equipment, I'm guessing probably not a lot? except for the solar part. A small solar panel recharging a battery adequately sized to last the night should absolutely be able to keep a meshtastic node going.
There is this video on using an insulated thermal mass with a peltier generator, attached, and that seems to be able to produce power fairly consistently, though according to spec sheet for that generator, it'll only produce 119 milliwatts (0.19 watts) with a 30 degree temperature differential.