Solar pile driver. 4:55 video.
https://www.youtube.com/watch?v=2XDYa4UaPrk
Previously:
https://www.homemadetools.net/forum/...400#post181527
https://www.homemadetools.net/forum/...950#post175737
https://www.homemadetools.net/forum/...108#post172309
https://www.homemadetools.net/forum/...887#post164046
https://www.homemadetools.net/forum/...598#post162794
https://www.homemadetools.net/forum/...567#post155235