Electric Foreigner - a catamaranEP converson project

[Vinny Barbarino]

Hi all,

I've made the decision to convert my 49-year-old Sailcraft Apache catamaran named Foreigner to electric propulsion. She's 41 foot and approximately 7 ton displacement.



The process is already underway - I've removed most of the existing diesel system (and a rather extensive custom one-off hydraulic system, read below), and I'm about to pull the trigger on ordering.


Foreigner originally had two diesels. However, some decades ago, the original system was converted to a single centrally located Perkins 4.108, with a hydraulic system powering a large frame holding a centrally located prop that lowers into and out of the water, and pivots for (some) maneuverability. However, this hydraulic system is old and has problems, and is in need of such expense that it's simply not worth keeping.

After considering all options I've decided electric Pods are, on balance, the best option for me. This seems to be a good candidate boat/situation for such a conversion. Electric pods will be cheaper than two diesels (etc), I'm an owner who is has no unrealistic expectations of speed/range whilst under power, and the boat is in need of re-powering essentially from scratch.


I remain undecided upon epropulsion or Torqeedo. I'll decide in the coming days, and make the order.
Either way, I will be opting for 2 x 6kW pod motors, each with an e175 or equivalent battery.



IMHO, the main problem with ePropulsion system is the ePropulsion batteries - the e175's are VERY heavy (leading to logistical issues).... and the main problem with opting for third-party batteries is hydrogeneration won't operate. If it weren't for these downsides, I would order ePropulsion today. The Torqeedo system will be more expensive (even using third party batteries, and this is the conundrum - in most other ways the two systems are quite comparable.

Any input appreciated, and I am more than happy to document the process and report results - short term and long term.

Cheers!

[CatLove]

These pods aren't such a good idea. I've seen an EPropulsion pod disassembled .

My concern is water intrusion and causing unnecessary haul outs.
The pod has a front lid or cap that is attached with 4 screws to the main body and it holds the front rotor ball bearing.
There is a skinny o-ring compressed by these 4 screws between the front cap and the main body. This o-ring is about 1/16" or something like that (didn't have my calipers with me to measure) in cross section.

There's a similar arrangement at the aft end, a cap also held by 4 screws and compresses a similar o-ring toward the main body. The motor shaft is also the propeller shaft, being direct drive. It sits on a single ball bearing at the front and 2 ball bearings toward the propeller.

The unit I saw had some clear silicone sealant shoved into the screw holes . There were no o-rings on the screws .

The pole windings were kinda enclosed in clear epoxy , not a complete encapsulation, more like a thick layer but you could still see individual copper wire turns .
While this whole construction appeared robust for an outboard, in my judgment at that time I didn't want to cut holes in the boat, nor the risk of water intrusion due to failed orings or sealed ball bearings. I decided to go for the outboard version .

Given that motors are needed only a small fraction of sailing time and sailing time is more or less a fraction of the total time the boat spends in the water, the outboards will see a very small percentage of time in the water compared to the pod version. In addition, pulling outboards out of the water doesn't require a haul out . Just my 2 cents.

[SaylorMade]

Originally Posted by Vinny Barbarino

Hi all,

I remain undecided upon epropulsion or Torqeedo. I'll decide in the coming days, and make the order.
Either way, I will be opting for 2 x 6kW pod motors, each with an e175 or equivalent battery.



Cheers!

Try to get an actual quote for the Torqeedo.
Intially the ePropulsion looked quite a bit cheapter to me too, but when I got an actual quote for the Torqeedo including folding propeller and other accessories, it came out at the same price. (3rd party batteries of course, which also does hydro generation on the Torqeeo).

[Vinny Barbarino]

Originally Posted by SaylorMade

Try to get an actual quote for the Torqeedo.
Intially the ePropulsion looked quite a bit cheapter to me too, but when I got an actual quote for the Torqeedo including folding propeller and other accessories, it came out at the same price. (3rd party batteries of course, which also does hydro generation on the Torqeeo).

Thanks SM - yes, I reached this same conclusion. Torqeedo is the way I will go (with third-party batteries).

[Vinny Barbarino]

Originally Posted by CatLove

These pods aren't such a good idea. I've seen an EPropulsion pod disassembled .

My concern is water intrusion and causing unnecessary haul outs.

Thanks CatLove. Although outboards are an option (my transoms are vertical), I have decided that Pods are the better choice in my application. However, I'll go with Torqeedo - they appear to have a better sealing system than ePropulsion. Hoping to order this week.

[Statistical]

Following. While cats are the most direct fit for pods I would see a pair of pods being used for monohulls eventually. Moving the motor outside the boat would allow the entire engine bay to be used for an even larger battery bank.

[mcarthur]

Originally Posted by Statistical

Following. While cats are the most direct fit for pods I would see a pair of pods being used for monohulls eventually. Moving the motor outside the boat would allow the entire engine bay to be used for an even larger battery bank.

I'd love to add a pair of pods on our powercat, with the option of large sized, slow moving props for upto-hull-speed. Say 600mm++ diameter for us. Have you seen anything like that?

[Vinny Barbarino]

UPDATE:

After a *lot* of research and speaking with Torqeedo and ePropulsion, I have ordered ePropulsion. But there is a nuance...

I've ordered 2 x Pod 6.0's, but not with ePropulsion batteries. They're simply too large/heavy for my liking. The downside: I will not be able to use the regen feature, and one upside - using third-party lifepo4 is a very significant $$$ saving on the total system. I'll compensate with a large battery bank (more AH than the ePropulsion system, my solar will be upgraded (1400 watts total), there will be a generator, and my expectations are that I'll be sailing much more than I'll be motoring.

Prep for the install is well and truly underway - the older system (hydraulics/diesel) has been removed, holes fibreglassed, etc.

However, as I'm currently in Trinidad, delivery times mean I wouldn't expect to be commencing installation for another few weeks or so. I'll add photos at that time for anyone who is curious.

[mcarthur]

Glad a decision is made. What genset are you thinking of?
If DC (which I would strongly suggest), there's only a few options out there unfortunately.

[Statistical]

Originally Posted by mcarthur

Glad a decision is made. What genset are you thinking of?
If DC (which I would strongly suggest), there's only a few options out there unfortunately.

Or you could make your own DC generator out of any small marine diesel.

Now that inverters are large enough to support all household loads it would be nice if we saw more DC generator options.

[YesIsail]

Originally Posted by SaylorMade

Try to get an actual quote for the Torqeedo.
Intially the ePropulsion looked quite a bit cheapter to me too, but when I got an actual quote for the Torqeedo including folding propeller and other accessories, it came out at the same price. (3rd party batteries of course, which also does hydro generation on the Torqeeo).

Hello sailor!
can you share the distruibutor you talked to?
Thank you

[SaylorMade]

Originally Posted by YesIsail

Hello sailor!
can you share the distruibutor you talked to?
Thank you

I don't know if it's going to help you, because I live in Denmark

But here it is:
Solbaaden

[Vinny Barbarino]

Update:


Today (on the hard here in Trinidad), the Port engine was tested (along with the display/throttle/etc). So far, so good.


More details:



ePropulsion Pod Drive 6.0 Evo (x 2) are installed, along with 16 x 100Ah LiFePO4 batteries (8 for each motor, wired in series/parallel). As mentioned, I did not go with the ePropulsion batteries primarily due to weight/physical size, with the secondary factor being a substantial cost savings going with "other" batteries.

Hydrogeneration will not work with "other" batteries, that's the downside. I've also read that *possibly* the ePropulsion display will not be 100% accurate in terms of SOC of these batteries, so I've installed 2 x cheap (but accurate) shunts/displays at the batteries to determine if this is the case.

My solar installation will be 1540 watts (so far, I've installed 2 x 370 watt panels, have another 400 watts to install, and a final 400 watts I'm waiting on delivery from USA to Trinidad).

I have a Honda EU2200i generator, and I'm waiting on a 48 volt charger.

Hopefully tomorrow the other motor will be also running.

We may splash in a about two weeks, but possibly not for a month.

I'm happy to answer any questions - so far I've been very happy with the installation process, and the quality of all of the ePropulsion components.

[seandepagnier]

regen would work poorly because the propeller is not cambered for it, the efficiency (power vs drag) is half what it should be.


You should instead seriously consider a dedicated hydro generator (or 2) to charge while under sail. If you eventually get regen working somehow too, it will only add to your power generating capabilities, but you will find a dedicated generator to have much better efficiency.

[Vinny Barbarino]

Well overdue update:

We had a couple of "false starts" moving SV Foreigner from the hard into the water, hence the delay on the updates.

A couple of months ago, on the day of splashing, I noticed an issue with one of the driver control units. This was replaced under warranty by the dealer (Florida based), with an exceptional level of service and support. Thus, we never splashed at that time.

About a week ago, we splashed, and have since performed a couple of tests. Honestly, I was not paying close attention to exact data, being more concerned about a thousand other things on the shakedown sail (as this is a 50-year-old catamaran that I have personally done a lot of work on!).

Initial thoughts:

The epropulsion motors are fantastic.

Docking is an absolute breeze, I've never experienced a boat that can so quickly move from forward to reverse. The power is very close to instantaneous - and there is a significant amount of power for the ~7 ton displacement.

Full power I believe I was at about 6.5 knots STW. However, there is a chance I wasn't actually at full power at the moment I noticed we were at 6.5 knots. My gut feeling says we could achieve a higher top speed.

With a decent amount of motoring, against a strong Trinidad Boca current, we were easily doing 4.5 knots, for a good half hour or so.

At low speeds, the power usage is surprisingly low. With a typical day sail around here, with strong currents etc, we motored for around an hour at or close to top speed, docked, performed some other maneuvers, and had plenty of battery left upon return (we used ~40% of battery).

One issue - we have third-party batteries, not ePropulsion batteries. On the display, the reading of battery "percentage available" is incredibly incorrect. The voltage available is fairly accurate. There are some settings that I can adjust to try and improve this reading.

With more journeys under our belt, I'll update a little further.

The summary is - so far, I am incredibly impressed.