Quint B.U.I.L.D.s developed a system that (barely) charges his cell phone with downspout water flow. His four-part (so far) video series documents his engineering, trials, and improvements. He tries different turbine designs, builds his own alternator, manages the current and voltage, and buffers the water flow. He shows the engineering challenges of implementing a back-of-envelope design. Good fun.

1. How to Harvest Free Energy From Your Roof with a Hydro Electric Generator! https://youtu.be/S6oNxckjEiE

2. 3D Printed Alternator vs. DC Generator for More POWER From the Rain! https://youtu.be/YLb4enCgnP4

3. Fidgeting With Turbines! https://youtu.be/vify0k2sHlQ

4. Charge a Smartphone With The RAIN!!! https://youtu.be/amu5LJaDUPY