Electric propulsion and regenration for high speed sailboats

[kistinie]

Electric propulsion and regeneration for under 10/12 Knts sailing boat is a rather simple thing as the close to square effect of speed for torque applied on the propeller remains acceptable.
But in the case of a well designed cat, tri or prao reaching 15 to 20 Knts the drag effect and vibrations will become a real problem. I do not speak of racer reaching 30 Knts, even 45 in case of Orange or IDEC where effect is dramatic !

Obvious solution would be a Variable Pitch propeller (we say in french), CPP in English (thanks m-saha for recall to order !), but this solution is expensive and it seems industrial products are missing for power range around 10Kw
Autoprop is a part of solution but above 12 Knts, i doubt it works

Other solution would be to have two distinct device
one big pitch to motor and regenerate low speed, then fold
second small pitch producing energy for high speeds

Of course in both cases the motor controller, playing on regenerating curent can also control the torque applied on propeller, but is this enough for very high speeds ?

Is there a distinction to be made between shaft drive and pods ?

Last thing to think about is that in case of surface propeller experience shows that you collect plastic bags, sea weeds and other net, that block the regeneration...

What inspire you these two solutions ?
Do you have others ideas ?
A gearbox ?
A reduced propeller diameter and increase Rpm to the cost of a reduced efficiency doesn't please me very much, but may be is this just a bad preconceived idea ?

[pistnbroke]

get an outboard and stop pi..ing about

[kistinie]

Yes, it is an option.

But sadly I'm afraid this is too late as i have already sold on ebay my grand-father underpants and motors, just kept his jenny bad habits

[kistinie]

I do not know if it is your prophetic name or your sense of humour that inspire me for my Australian born boat, but when you talk to me i get new ideas !
Many thanks !

So here is the solution i think about :

An electric pod with CPP pressure oil controlled by a small outside pump.
Gives the pitch change and water protection.
Could also be electric command
No long mechanical tubes...

I would be extremely surprised if we do not see soon on the market these kind of CPP pods for leisure boats
Imagine it is in central position of your sailing boat, you can rotate this pod 90°, then you may get close to orgasm. Sailing orgasm of course.

[FAST FRED]

CPP pods for leisure boats
Imagine it is in central position of your sailing boat, you can rotate this pod 90°,

Sailing craft usually have keels or other methods for KEEPING a boat from moving sideways , rather than forward.

A dock line will be more efficient than an Azpod for docking.

FF

[kistinie]

Of course works much better with multihulls and retractable daggerboard !
Sorry
Yes this was a bit egoist...

But i'm not certain it is as bad as this with daggerboard down
Just slow

What is a dock line ?

Ok understood !

I often single handed my trimaran, and with a size 40x31' and very brittle cold molded luan hull ....i let you imagine why i dream of a 360° propulsion (-+ 90° x Fw + Rv)

[mydauphin]

Kistinie, one thing you forget about boats. Most people, even rich people with yachts are on a budget. The need something that works everytime and off the shelf. The KISS solution is the best. Also the guy with money is too smart to spend it on new ideas that may not even be insurable. As far as 360 propulsion for years, I had a electric remote trolling motor on my 26' 700hp speedboat. It couldn't idle worth a darn, I used electric to dock and travel canal home. later...

[kistinie]

You are right, marketing of new product is another real job.
I take this in account for my project of course.
A friend is in charge of this "market" question.
I also take care of security aspects
Security of users and mine too as some part of the project may upset some actual industry actors
I will probably do a kind of join venture with industry associations and the french gov to have some ideas accepted softly
Regards

[gideon]

We will start to sell retractable electric motor/generators in the power range from 8 to 24 KW

[gonzo]

Electric trolling motors have fix magnets. You could have two propellers, one for propulsion and one for charging. Changing them means slipping a pin out.

[gideon]

we try to go the route of having one prop forward facing that does both in a acceptable way giving the major accent to generation since he system is meant for a sailboat.
gideon