is a PITA - that is why it is so hard to fish. I figure it is about 100 lbs load to pull in when going 7 knots. Not worth the effort to pull it in to fish for a couple of hours. I never slow down unless I have to.
The issue of generating power via your propulsion system is wear. Friends who did that ended up replacing thieir cutlass bearing annually. Conventional packing would be a big friction source (and a wear point) too.
They had a lay shaft parallel to the prop shaft with a pully system to increase the speed enough to drive a standard alternator. I know Calder is experimenting with electric drives that would also serve as alternators but the packing and cutlass bearing issues are the same.