Hmmm my experience sailing in the San Juans is that the winds are far more fickle than my boiler & power plant
The design trade-offs (space, shape of hull, etc) needed for successful sail propulsion are substantial... you're better off squirreling a small outboard
in a locker and using that if needed. If your boat is large enough that that wouldn't provide enough drive, a small air cooled diesel could be used for emergency power, belted to the prop. shaft... alternatively, a generator could be used to drive an electric motor...
- Bart