piston effect to work like and induction coil

Greetings
I have worked in the logging/sawmill business for 35+ years. There are a few instances where I would like to know if a benefit of additional work can be found in existing activity. The first is a piston effect. I have a 4" 'piston rod' travelling up and down about 20' with a stroke time of about 2 seconds (sort of like a pile-driver). Can this be made into an induction device; magnets passing through coils to create a usable electric current? If so, where would I find tables telling me how many magnets and coils of what size or weight I could put on the 'piston rod'. Would it be one coil and magnet? one coil multiple magnets? multiple both? The available horsepower working the piston is many hundreds
A buddy of mind (not an engineer) said this is being done with pumpjacks on oil fields.
Any help will be greatly appreciated.
A second is in log hauling. One method of bringing felled timber to a concentration/transportation site is using a yarder. The yarder is a winch; the mainline cable is drawn out from the yarder into the cutblock where the felled trees/logs are.Choker cables are wrapped around the logs; the choker cables are attached to the main line and the yarder winches them in to the landing.
The yarder is powered by a diesel. For this example about 500hp running at 1400rpm. The yarder draws the logs in at about 1ft/sec.
My question is could the diesel be replaced by a generator, such that the intent is reversed? Instead of drawing in logs the mainline is drawn out, the yarder transmission goes from 1ft/sec to turn the generator shaft at the same 1400rpm. I suppose its clockwork through the transmission. How much weight would have to be drawn by the mainline to turn the generator shaft? At 1400rpm how many horsepower are developed?
Thank you for your time.