Electric Sail Boat Motor

[JCR]

Scotty,

I have authorization from Electric Yacht to install Electric Sailboat kits and have designed, installed and sea tested propulsion drives as well. There are many companies offering electric boat conversion motors, controllers, reducers and complete kits including Solidnav, Asmo Marine, Electric Yacht, Solomon, EV sports, Vetus, Oz Marine, Elco, etc. Some kits start at $1,500 but buyer beware they do not include motor mounting hardware. Batteries to power your new electric propulsion system are never included. You might keep in mind that every boat is different and one does not fit all. If you have a sailboat or powerboat you want to convert to electric propulsion I would like to help.

My interest in propulsion design & engineering and elecric motor systems in boats goes back 10 years but advances in battery power density did not catch up until about 2006. There are many ways to push boats with electric motor propulsion. If someone tells you to use this kind of motor there are 10 other people that will tell you about 10 other motors. Some will recommend DC and others swear by AC and everything in between. The most important thing to consider if you are going to convert your boat from gas or diesel to electric propulsion is safety. The Underwriters Laboratories (UL) is in the process of developing national saftey standards for battery pack use in electric vehicles as is the SAE.

JCR

[ChicagoNewport27]

Here is an example of a guy that repowered his Newport 28 with a Re-E-Power electric engine:
E-POD 3000+ - Petaris' Photos

We've been discussing it over on the Capital Yachts/Newport mailing list, here:
Yahoo! Groups

To quote the owner, Justin Paulsen:

Well the first thing that I'll mention is that it has torque. Forward and reverse are both very responsive and since we back in to the slip it has made a big difference. We are still really getting used to the system, even though this was season 2 with it, as since we installed it we haven't had a lot of time to use it. Though it has had some good tests. The hull speed has slowed and there is a bit more drag when sailing. The batteries have never run out and I have given them a good 8 hours of use before charging them again. We are kind of guessing we could get 10 hours or maybe more out of them but haven't tested that yet, though I hope to next season. The recharge time is long and I usually let it go overnight but I would say its a good 5 hours maybe a bit more, though some of that is float time. I took the photos of the corrosion so that Kevin at Re-E-Power could see them and advise on it. He said that it wouldn't be an issue. That was after one season in the water and my seasons are generally the middle to the end of May until the first weekend in November. It didn't affect the operation of the motor though. By the way Kevin has been very helpful with any issues that have come up with the system though he can be difficult to get a hold of.

There have been issues though. For one the controller kept overheating the first season even after adding cooling fins and fans, though they did help a lot, and we had to have the prop pitch changed on Kevin's advice, we sent it to him and he had it done and sent back to us (he paid for all but sending it to him). Also the controller is something we came up with as the one that came with it was just tiny, ours is to but since we changed it we were able to mount it on the tiller which is both a great place for it, convenience wise, and a not so great place as its easy to bump with your leg.

[mitiempo]

Why would the hull speed slow and why would there be more drag while sailing?

[huguley3]

Originally Posted by mitiempo

Why would the hull speed slow and why would there be more drag while sailing?

They probably meant top speed. My diesel was smallish anyway so a replacement electric probably would have given me the same top speed had I went that route. The electrics can recharge the batteries while sailing by letting the spinning prop run the engine like an alternator. That adds some drag to keep the prop spinning. Even more so since most places recommend a larger prop on the electric.

[KeelHaulin]

Originally Posted by mitiempo

Why would the hull speed slow and why would there be more drag while sailing?

The motor is in a pod mounted beneath the hull; and the prop looks more like a powerboat prop than one designed for a sailboat.

[mitiempo]

Oh, I see.

[COOL]

Originally Posted by JCR

Cool

Tell me more about your boat, engine, propeller shaft speed and the existing saildrive.

JCR

JCR,
The boat is a custom built Lancer 36, originally
built as a race boat with minimal furniture.
The boat displaces 10,500 lbs on 29' LWL, so
it is very easily driven.
The engine is a Volvo MD 11C with a 110S Saildrive.
When I am able to get the machine started, which has always
been an issue, it will push the boat at 7.5 knots at 2500 rpm.
The shaft output is rated at 17 kW at that speed.
The ratio is 1.66:1.
The current prop is a 2 blade fixed , maybe a 16"x11", it seems
to be too much prop and the acceleration will throw off your
feet when you ease it in to gear. I will eventually go with a
folding prop of some sort.
I am guessing that I will not need a thrust bearing for the belt
drive, but I will build a composite structure to support the
Saildrive, since it was supported by the engine.
i do not know how yet to configure the ground loop
for the electrical system, that was connected to the
engine block.
My expectation is to get into and out of the slip,
we are sailors and not motorsailors.

[silverbranch]

Originally Posted by ChicagoNewport27

Here is an example of a guy that repowered his Newport 28 with a Re-E-Power electric engine:
E-POD 3000+ - Petaris' Photos

I looked at these pictures a while back and the ones on the last page look like the motor is in bad shape. So he is still happy with it and it's working?

[mitiempo]

I want to start by saying that I know almost nothing about electric boat propulsion. But after looking at all 165 pics in the link that was posted I have some questions. Why is the motor mounted like it is below the hull? It doesn't look too good in the last few pics I agree. Why not mount the motor inside the hull and use a normal shaft, stern bearing, and cutlass? Wouldn't this protect the motor a bit better? The angle of the prop looks wrong as well - the forward end of the nacelle is higher than tha aft end, resulting in a prop that is nowhere near the angle a normal fuel powered boat has for its shaft.

[tommays]

This would seem to be a pretty BADLY failed project as you still dealing with saildrives and other motors big issue water infiltration through seals and corrosion