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Planning to convert boat to electric, need parts and advice

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Wow. I assume you have already researched this in online electric boat forums before coming to a car forum.

I'll take a swing at this...

Displacement boats are very inefficient. Planing boats are worse.

First, you need to see the effect of carrying an extra 1300 pounds of weight (the batteries) on your boat's performance. Secure three 55 gallon drums on deck and fill them with water, then measure the gph of fuel you use to plane the boat. Since you probably use about 20 gph at WOT, let's guess at 14 gph (assuming you can get it to plane).

A car the size of a Tesla uses about 2 gph going 60 mph, so your boat uses about 7 times as much energy per hour as it takes to drive a car.

The Tesla can go for about 4 hours (240 minutes) on a charge at 60 mph. 240 min / 7 = about 35 minutes.

So you'll be able to have 35 minutes of fun, then just pull into the Supercharger at your local marina -- oh wait. No, you'll have to find a marina that had 50 amp service, and wait the 8 hours for the boat to charge.

My numbers are estimates, sure, but close enough.

Oops, just saw in your post that you have a diesel. Probably less fuel usage so my calculations are off. Maybe you get 45 minutes run time.
 
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A lot of this stuff seems off.

A car of Tesla's size, the most accurate example being a Tesla, uses about 1/2 gallon equivalent of energy, not 2, per hour going 60mph, ballpark. Right, because the boat is going to be electric we can assume the drive train is something like 3 or 4 times more efficient?

Regarding weight, you will add the weight of the electric components, but also subtract the diesel engine, the fuel tanks, and the fuel. I imagine a marine diesel engine is a beast and a large tank of fuel is easily a few hundred, if not a thousand pounds.

Correct me if I am wrong on any of this.

To Drtomca, just a thought, you could run your diesel on biodiesel or waste veggie oil. That can be a whole other can o' worms, but if you are doing this for ecological reasons you could be just as beneficial for less costs and maintain all functionality. I used to be a veggie oil guy, but solar charging a Tesla is so much less work, and none of the mess.

Good luck with your project.
 
If you read the details on the electric boat I posted here:
Ruckmarine Electric Sportboats - KONA 17 Specifications

Top speed: 27mph
Planing speed: 15mph
Time at top speed: 30 min
Time at planing speed: 45 min
Time at 5mph: 3.5+ hours

Battery size: 12.8 kWh
Battery weight: 328 pounds
Boat displacement: 1490 pounds

Those seem like reasonable performance goals, since it has actually been done and better than any napkin calculations.
 
If you read the details on the electric boat I posted here:
Ruckmarine Electric Sportboats - KONA 17 Specifications

Top speed: 27mph
Planing speed: 15mph
Time at top speed: 30 min
Time at planing speed: 45 min
Time at 5mph: 3.5+ hours

Battery size: 12.8 kWh
Battery weight: 328 pounds
Boat displacement: 1490 pounds

Those seem like reasonable performance goals, since it has actually been done and better than any napkin calculations.

Maybe I'm missing your point. Those look freakishly close to the performance numbers I'm reading off the napkin.:eek:

What I understood was that he was taking the running gear from a Tesla and putting it in this boat:

zodiac.jpg

It's a little larger than this boat:

zrib.jpg
 
Hmm... I have an 80's era Evinrude outboard that hasn't run in 20 years...

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Time at planing speed: 45 min

Those seem like reasonable performance goals, since it has actually been done and better than any napkin calculations.
I'm not sure I'd call 45 min of runtime on plane, for $50k, a "reasonable performance goal"

I hate to be a buzzkill, but practical performance electric boats (and planes) are a long way off, until batteries improve by orders of magnitude. People forget that cars need ~20-30hp at highway cruise. 100's of HP is used for a few second burst off acceleration. Boats and planes can use 100+ HP continuously. 100hp would kill an 85kWh battery ~1 hour.
 
Very do-able. I converted my 2016 Bayliner 175 to all electric and I love it. Here is a link.
This is very impressive - nice job! I found your other video, I hope you don't mind me posting it:
This second video has a tour of the installation and gives details of the motor, controllers, etc.

I'm also impressed that you'd pull the engine out of a new boat - I'm not sure I'd be that brave!
 
Boats suck up power big time both for planing or displacement, they might both be roughly equal. So time is your limiting factor. For water skiing or for simply going from point A to B you could convert from a medium sized EV that has a range of 80 to 100 miles and find the boat useful. Plus it would be legal for use on 'pure' lakes. Going displacement gives a lot more range especially if you ad a canopy with solar panels. If you need to get there faster take the highway instead.
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