Greetings! Just thought I'd throw this out there. I might take a shot at this on a future date if I'm still stuck inside, but for now my weekend wanes.
Concept Overview:
Windmill -> Axle -> Rotor -> Cable -> Battery -> Cable -> (whatever machines are desired)
The video that inspired this thought train:
https://www.youtube.com/watch?v=gQyamjPrw-U
This whole idea could be simple, or quite complex depending on how much effort one wants to put into it. The shaft mentioned at the 1 minute mark would be conceptually what connects to the axle. I believe overall this would lead nicely into post steel content.
Component Ideas:
Cable:
Glass, as a non-conductive material, can be used to coat copper wires (or ingots, pending on how detailed one wants to be). This process could be as simple as: [G = glass block, CI = copper Ingot]
G G G
CI CI CI = X-Cables, where X is whatever the balanced number is decided to be
G G G
in a grid, or more complex if other materials such as wires and glass tubes are made.
Magnet:
Magnets, a needed component for a rotor, can be made as simple as hanging a steel ingot vertically for a week (tool rack?). The following page has a few fun ways to create a magnet from a steel ingot:
https://commons.princeton.edu/josephhenry/permanent-magnet/#:~:text=Take%20two%20magnets%20put%20one,will%20become%20a%20permanent%20magnet.
Rotor:
In the spirit of keeping things simple [M = Magnet, CI = Copper Ingot (wire), II = Iron Ingot (rod), Cbl = Cable (the output), W = Wood (planks, casing, a chest?)]
M CI M
Axle II Cbl
W CI W
The center column would be to represent the copper solenoid. Hopefully I have this right, not an electrical engineer!
Battery:
A Voltaic Pile could be made with (ZP = Zinc Plate, L = Linen, CP = Copper Plate)
ZP ZP ZP
L L L
CP CP CP
https://en.wikipedia.org/wiki/Voltaic_pile
If one desires to make this a bit more complex, this could be a multi block structure where a stack of these would create a larger storage that scales with the amount of stacks.