From our offshore days I have some low rpm permanent motors for wind and/or trolling generators. They range in price from $200 to $50.
The one in the center of the photo provided all of our charging needs for most of a circumnavigation producing 10 amps in trade winds as a wind generator and 8 to 10 amps with 8 knots of boat speed as a trolling generator.
We also have a 28′ diameter parachute sea anchor for which we will be asking $800.
SUSURUMBA
Susurumba has been a live-aboard for 15 years and during that time we completed a 10 year circumnavigattion. We currently live on a floathome in Maple Bay.