From what i can see on the net its still cryptic
Harvesting voltage between dissimilar metals,,-https://www.google.com/search?…&biw=1958&bih=882&dpr=0.7 Harvesting voltage between dissimilar metals experiment
umidity energy harvesting.. The new device works a bit like a tiny cloud, explains Yao. His team's technology taps into the air's humidity. This creates a charge difference between the top and bottom of the device. That difference is big enough to harvest from those water molecules a small flow of electrons — that is, electricity