Electric Jet Boat

[nimblemotors]

I'm building a 16ft jet boat, and am considering putting in an electric motor to power it. If I do so, it will have to be a hybrid as no way I can put enough batteries on board to last a day of running around the lake, and even if I could fit and afford them, it would weigh too much.

Given this, what I'm wondering should I bother?

I'm trying to maximum the internal space for people, traditional jet boats half the boat is consumed by the engine. An electric motor to drive the jet would be very compact, but then a gas motor goes somewhere. I'm thinking it can be smaller and tucked away in the back under the seats.

In my 'inventory' of surplus parts, I have a 9in ADC motor that seems good as the motor, a 650cc jetski motor for the gas engine, and a Mars BLDC as the generator.

What ya think? Too complicated, just go with the turbo 12A rotary?

[2000mc]

not that i'm that familiar with these, but would a jetski engines cooling system and exhaust work normally like this?

[nimblemotors]

Originally Posted by 2000mc

not that i'm that familiar with these, but would a jetski engines cooling system and exhaust work normally like this?

A jetski uses the jet as its waterpump, so to run it without the jet an external water pump is needed.

[cRiPpLe_rOoStEr]

I'm not so used to jet-boats, but recently I've been looking at some hybrid setups from an Italian company.
That might inspire you: http://www.fnm-marine.com/gallery/mo...S%20HYBRID.pdf

[justme1969]

There are alot of pleasure boats now that are electric drive and you may be surprised at how long the batteries last for pleasure use. The jet ski drive Idea is brilliant.
Ive already had same Idea myself but insofar as most of my Ideas I cannot afford to act upon.
The most feasible idea I contemplated was twin jet ski motors nothing too intense and A fair sized electric main drive.
This was for a Tri Cat though and much of the roofline in No Step areas would be solar chargers.
Two wind turbines one small one fixed to mainsail. And a restowable larger one for fast charge. Enough of my dreams though. dont get a boat that is tough to get up onto plane or it will just be an energy leech. A design that is light and will rise up outa the water at low speeds is what you need to look for like slim bass boat etc.
I would love to see you do this build really the single jet ski motor may not do as well as expected though. The internal pitch is designed for high speed economy and its probbably never going to get there alone. I wanted mine for emergency and port navigation they would have been quite overwhelmed by the weight and displacement of the tri cat for just motoring along.

[justme1969]

Dang Rooster there went my other Idea! Ford, Cummins, and Toyota were working jointly on a pancake motor in place of clutch / torque converter that never seen light of day about 9 years back That was my inspiration for the boat drive since all inboards are inefficient now compared to outboards.

[P-hack]

I would say a yanmar on biodiesel is your best option, weight (and reduced range) is a much bigger penalty for things that must "float" on a fluid (boats and planes) vs things that roll on wheels. And there isn't much regen opportunity but a lot of time spent at a constant speed (where the losses of mechanical to electrical to mechanical will be amplified).

Biodiesel will get you your green merit badge as it is renewable. Electric/hybrid planes/boats don't make a lot of sense to me in the bigger picture.

an electric trolling motor on a kayak (with an RC airplane prop mod) makes sense just because it is ridiculously inexpensive to set up.

Note, the coast guard has some regulations about internal combustion engines to consider also.

[P-hack]

last thought, convert an outboard to run on ethanol (also renewable), far less obvious if the coast guard does take an interest in your motor, but not as efficient as biodiesel, though more efficient than a generator driving an electric motor.

[cRiPpLe_rOoStEr]

If you would want to run ethanol in an outboard, I'd strongly advice to get a 2-stroke one and run it with some vegetable-based oil, such as castor oil.