Com-Pac Yacht Owners Association

Com-Pac Model Specific Discussions => CP-23's => Topic started by: H2operator on October 25, 2019, 09:44:48 AM

Title: Installing Prop shaft for electric motor
Post by: H2operator on October 25, 2019, 09:44:48 AM
Hey All, I did a quick search in boat and equipment mods and didn't come up with anything. I'm curious if anyone had ever converted a non powered CP-23 to inboard power? I thought about maybe using and old Saildrive unit but figured that adding a conventional prop setup would be no more difficult and less likely to have typical Saildrive issues. For a trailer boat electric really has a lot of advantages. I also looked through my old version of Gougeon Bro's on Boat construction without luck.
Thanks, Lance
Title: Re: Installing Prop shaft for electric motor
Post by: wes on October 25, 2019, 10:08:53 PM
Keith Scott at The Sailboat Company is your man. He has done this conversion for diesel and possibly electric too. He'll talk your ear off if you call, and he's forgotten more than I'll ever know.

Wes
Title: Re: Installing Prop shaft for electric motor
Post by: H2operator on October 27, 2019, 12:14:13 PM
Thanks Wes! I'll check it out...
Title: Re: Installing Prop shaft for electric motor
Post by: H2operator on October 31, 2019, 04:09:42 PM
Photos from the web site...
Title: Re: Installing Prop shaft for electric motor
Post by: moonlight on November 10, 2019, 02:42:27 PM
Have you completed this install, or still researching?
What are you using for electric motor?
Lead or Lithium batteries?
Title: Re: Installing Prop shaft for electric motor
Post by: H2operator on November 12, 2019, 02:45:05 PM
 I'm still planning actually just starting to do research. I've been watching the progress on Sailing Uma and the efficiencies are pretty amazing especially with the right lithium ion batteries. When you consider the small loads for a CP-23 and the other systems that can use the power electric looks really good. Of course solar is absolutely necessary.       
Title: Re: Installing Prop shaft for electric motor
Post by: moonlight on November 13, 2019, 10:28:58 PM
Solar will rarely provide sufficient charge; but with a sizeable array it may.  Trouble is, a 23 doesn't have that much real estate to convert to solar...
Regardless, yes, lithium is the way to go.  And shoreside recharging is simple and efficient.
We typically size propulsion battery banks at 200Ah as a base, then depending on how much of a cruising range is desired we increase from there.
We're actually working a system now that's only going to have 100Ah propulsion bank; but it's a very large vessel (45') and will be hybrid with a generator.  So the batteries are solely for in and out of the harbor on daysails; anything longer and he runs a hybrid arrangement off the genset.
Hardest part is he's driving the equation, and has made some concessions I would not.  But it's his checkbook, and we've identified the pitfalls clearly; and it's still a modular system so he can expand or contract as he sees fit.
Title: Re: Installing Prop shaft for electric motor
Post by: H2operator on November 20, 2019, 02:31:17 PM
I should have included regenerative charging of the prop as an additional option. I would refer you to the latest upgrade done on Sailing Uma, they have two large panels in the aft cockpit area. They have a Pearson 36' with a substantial electronic and refrigeration load.
Title: Re: Installing Prop shaft for electric motor
Post by: moonlight on November 20, 2019, 09:29:39 PM
There's an all electric catamaran that's been in these parts; by the time they're out of New Orleans and half-way across the Gulf they are streaming videos constantly and flushing away hot water because of their regenerative charging.

But their hull speed exceeds 10 or 12 knots too.

I wouldn't count on much regen from a CP 23 at 4 knots.  But over extremely long distances it will pay off.  But not many cross oceans with CP23's, although they could and should.

Nor is there much area for solar.

Best of luck!