A crazy idea?

[claydog]

I've been kicking around an idea for a while for a hybrid drive for use in a light weight planing Cat. The Cat I have in mind is only intended to be better looking,with a bit better rough water performance, than a typical pontoon boat. The drive system I've been thinking about uses a snowmobile 2 stroke motor and drive system for primary propulsion and an electric motor connected to the jack shaft via belt that can operate as a secondary “quite” drive while fishing or cocktail cruising. If my understanding of electric motors is correct the E motor can also work as a generator while under power of the gas engine to help keep the batteries topped off when away from the dock. This is just a little more than a napkin sketch and there's a lot of true engineering that's way over my head that I'd have to hire out if I was to go any were with this. The amount of knowledge freely shared on this site is incredible and I'd really like to hear opinions of what I've been thinking

[Stumble]

There are dozens of threads covering this on the board, but the short answer is that the energy density of batteries is about 1/50th that of diesel or gas. It is possible (though very very expensive) to do something like this, but it really isn't practical given the huge installation of batteries.

If you really want to do something like this, then installing a trolling motor is about the best option.

[daiquiri]

Claydog, your're pretty good with that 3D drafting software.
I think this idea is viable, though it will be costly. You should hear Jeremy Harris for details about battery and e-motor sizing, electrical wiring and about charge regulators necessary for the battery-charging phase. He is in the electric-boating world.
Stumble, I understand that the electric drive will be used for trolling and low-speed ops, which is ok. Going at planing speeds with batteries only is, of course, out of question.
Cheers

[kerrett]

Hi daiquiri, I wrote you via mail... Sorry to disturb you..

[whitepointer23]

looks like a good idea, i don't see why it has to be expensive, motors are available cheap and a couple of n200 cat batteries would power it for quite a long time and when it slows you just run home on the petrol motor. i met a bloke who ran a trolling motor on his 12 ft tinny and he gets 4 hours out of an n70 landcruiser battery. i can understand going the hitech expensive route for a fancy electric vessel but its not like you are relying on batteries to get home.

[daiquiri]

Ciao Kerrett,
ho visto il messaggio ma non ho avuto tempo per rispondere. Se non ti dispiace, lo farò oggi pomeriggio, con più calma.
A presto

[kerrett]

Grazie mille, nessuna fretta, era solo per sapere se ti era arrivato..
A presto

[claydog]

Originally Posted by Stumble

There are dozens of threads covering this on the board, but the short answer is that the energy density of batteries is about 1/50th that of diesel or gas. It is possible (though very very expensive) to do something like this, but it really isn't practical given the huge installation of batteries.

If you really want to do something like this, then installing a trolling motor is about the best option.

Stumble,
Thanks for the comment and I hear what you’re saying, a trolling motor certainly is the easiest and most cost effective way of running a boat on an electric motor. I work in the automotive design business and have been involved in enough concept builds, that building a custom car for myself just for fun has lost its appeal to me so I’m looking into building a custom boat. Mostly I’m in the very early stages of the design spiral and exploring a few different ideas that combine the key attributes of the 2 different boats I need to cover the way I use boats if I just went out and bought something off the shelf. Being an avid snowmobiler and having built a custom electric golf cart for a customer in the past, this idea been kicking around in my head for a while. I’m hoping a few of the electric boat gurus will chime in to help me figure out if my expectations of performance are in the ball park of reality.


Regards Andy

[claydog]

Originally Posted by daiquiri

Claydog, your're pretty good with that 3D drafting software.
I think this idea is viable, though it will be costly. You should hear Jeremy Harris for details about battery and e-motor sizing, electrical wiring and about charge regulators necessary for the battery-charging phase. He is in the electric-boating world.
Stumble, I understand that the electric drive will be used for trolling and low-speed ops, which is ok. Going at planing speeds with batteries only is, of course, out of question.
Cheers

Thanks Daiquiri, I think I do OK, but I work with too many people that are really good to consider myself anything but OK. I’m hoping Jeremy will take an interest and can give me a bit of E-boat for dummies advice.

Regards Andy

[whitepointer23]

Originally Posted by daiquiri

Ciao Kerrett,
ho visto il messaggio ma non ho avuto tempo per rispondere. Se non ti dispiace, lo farò oggi pomeriggio, con più calma.
A presto

thats what i would have said.