When any of you find a way to explain this in other words, please do.

----> https://scitechdaily.com/new-droplet-based-electricity-generator-a-drop-of-water-can-light-up-100-led-bulbs/

Stuff falling can generate electricity by squeezing 2 plates together. This includes falling things as small as raindrops. This team found a way to make this process even more efficient and gather more power from each drop with less loss. 

It appears that a single droplet of water can generate 50nC at 140v i.e. 7 microjoules.

And a litre of water/second falling from 15cm can generate 70mW. I suppose that's about 1.5W of kinetic power so the efficiency is quite impressive.