Three phase alternating current generated from an axial flux alternator.
I did find plans which seem to describe themselves as open. I might get around to posting them at a web site, but that exists much less than other comprehensive banks of searchable information on the internet.
Someone suggested some alternators constructed with as many wooden parts as possible, which makes the whole endeavour more accessible and energy efficient. Thank you HPR new year show, for that.
Wind turbine towers are the difficult part, and obviously dangerous.
Tiny generators are cool to cobble from discarded equipment junk.
A solid axial alternator is easy and robust. They can channel a lot of power if the wires are thick enough. Gears exist.
Pedal, and hang sacks.