A weather guy points out the obvious, EBM saying the needful, and in the “It’s happening, pay attention” department…
OK, I’ll say it… Some sort of propulsion system is a good thing to have on a sailboat.
I also think any propulsion system, whether human, diesel, gasoline, or electrical, makes sense where passage making is concerned. In fact, any sort of mechanical propulsion system is really only a convenience when you think about it. Getting in and out of tight places, being able to motor when you can’t sail point A to B, and in an emergency.
On our 7-ton Islander 36, we have a raw-water cooled, 27HP Yanmar. I expect it’s at least 30-odd years old and it’s an impressive beast.
Our 5-ton CAL 34 has a 6HP outboard and, in my opinion, it’s a near perfect auxiliary engine. Well, I’ll admit that the outboard on the transom is not at all pretty.
My rule-of-thumb where horsepower is concerned for an auxiliary engine is Tom Colvin’s “One HP per ton”. Which, in my experience, works just fine. With the exception of the Panama Canal and with no plans to do the ditch, an 8 HP engine for the Islander is really all I’d ever need.
We had several electric propulsion systems on the CAL and they all worked better than the outboard. They didn’t ruin the lines and cost pennies on the dollar compared to what a diesel would cost. However, the EPs used a ton of electricity and we had very little range with a 48V, 200-amp hour, lead-acid battery bank.
While range might be problematic where passage making is concerned, it still worked well as an auxiliary. We abandoned electric propulsion as keeping the bank charged was more hassle than we cared to deal with. In fact, we used more fuel keeping the battery bank charged than spent on fuel for the outboard.
Our thoughts on a new propulsion system for the Islander is if it’s working it does not need to be replaced. Of course, I’d love to replace the Yanmar as it takes up a shit ton of room. Room that would be much better utilized as storage, plus the cost of upkeep for a diesel is painful.
I do go on, don’t I?
For me at least, I see using an auxiliary propulsion system being akin to using a bow thruster or powered windlass (we have neither). You run them when and only when you need them… Anything you do on a sailboat should be about sailing and your first reaction should always be to sail rather than motor.
Sure, you might have to up your skill set and sometimes the learning curve can be steep. Then again, you get to walk the talk and that is no bad thing.
More tomorrow with a $3000 dollar system…