ePropulsion Pod Drive

Bull City

Bull City
6,895
2,534
North Carolina
I asked my ePropulsion dealer for advice on when I should charge the battery. It's a LFP battery, and it's supposed to have 3,000 charge cycles. I had an issue several weeks ago with low voltage and the BMS, which appears to be resolved. Here's what he (and electrical engineer) said:

As with nearly every recently introduced technology, there are diverse opinions regarding what constitutes "best practices".  Lithium batteries simply have not been in widespread use long enough for a solid consensus to form on issues such as exactly what charging practices result in the longest lifespan.  This is in contrast to things like oil changes in your car.  Cars have been around long enough such that mechanics will be fairly consistent in their recommendations on this and other topics.

That said, the E-series batteries are rated for 3,000 cycles at 80% DoD [depth of discharge] which means that the rating is valid as long as you never take them below 20%.  Most experts agree that if you never take them below 40%, they will last longer than 3,000 cycles - but nobody really knows how much longer the lifespan would be.  So as a practical matter, if you start with a fully charged battery and return with  90% still left, I would not bother charging it.  I wouldn't bother charging it if it was down to 60% unless I knew I was leaving the next morning on a long trip for which I knew I would need a fully charged battery.  I would recharge at 50% to avoid forgetting about it.

I found this pretty helpful. Comments?

 

JTE

New member
Finally have the boat in the water and numbers for the ePropulsion Spirit Evo 1.0.   Boat is a 1978 Wilderness 21 (1800 lbs displacement by spec).  New bottom paint (epaint EP-2000).

Spirit Evo 1.0 with 1.2KW battery mounted on top.  Boat speed measured with DST810 that has been calibrated.

RPM / Watts / Boat Speed (knots)

711 / 201 / 2.6

804 / 295 / 2.9

886 / 396 / 3.1

967 / 514 / 3.36

1016 / 607 / 3.56

1070 / 710 / 3.65

1120 / 806 / 3.65

1159 / 908 / 3.8

1195 / 1000 / 3.85

Range with this battery will be sufficient for day sailing in our bay.  That was the goal.   Top speed was right around where Alex at Seattle Boat Works predicted.   I’m happy with how it turned out.   Motor tilts up to parallel with water surface, no dragging.  This is the first electric motor for a boat that I’ve used.  The quiet is really nice.

F7C42DEF-1E9B-47BF-B3E7-063EF24C4CB2.jpeg

 

ProaSailor

dreaming my life away...
6,018
732
Oregon
Finally have the boat in the water and numbers for the ePropulsion Spirit Evo 1.0.   Boat is a 1978 Wilderness 21 (1800 lbs displacement by spec).  New bottom paint (epaint EP-2000).

Spirit Evo 1.0 with 1.2KW battery mounted on top.  Boat speed measured with DST810 that has been calibrated.

RPM / Watts / Boat Speed (knots)

711 / 201 / 2.6

804 / 295 / 2.9

886 / 396 / 3.1

967 / 514 / 3.36

1016 / 607 / 3.56

1070 / 710 / 3.65

1120 / 806 / 3.65

1159 / 908 / 3.8

1195 / 1000 / 3.85

Range with this battery will be sufficient for day sailing in our bay.  That was the goal.   Top speed was right around where Alex at Seattle Boat Works predicted.   I’m happy with how it turned out.   Motor tilts up to parallel with water surface, no dragging.  This is the first electric motor for a boat that I’ve used.  The quiet is really nice.

View attachment 505913
A heavy price in power consumption for little gain in speed above '1016 RPM / 607 watts / 3.56 knots'.

 

kiwin

Member
326
218
Auckland
Would a larger, slower turning prop do better, i.e. higher efficiency, or, as I suspect, does the resistance curve of the hull dictate that the power required to go faster is much higher?

 

Bull City

Bull City
6,895
2,534
North Carolina
A heavy price in power consumption for little gain in speed above '1016 RPM / 607 watts / 3.56 knots'.
Not necessarily the same data points, but there is a non-linear curve which punishes higher speeds and rewards lower speeds with shorter or longer ranges. All things in moderation!

 

Bull City

Bull City
6,895
2,534
North Carolina
Final Update:

I am so f*cking happy with this pod drive.

Getting underway is so much easier. No schlepping of the outboard to the stern, no schlepping of batteries, no gasoline smell. Just push a button and turn a switch and power awaits. The hardest part is running the extension cord to the dock to re-charge.

Time to anchor and want a little power to get to the right spot? No worries. reach into cockpit cubby, grab the throttle, and push the handle forward: instant power! No need to crawl back to stern and tilt motor into the water.

Need to get home and punch into a 15+ knot headwind? No worries! Plenty of power.

With a fully charged battery, at 3.5 knots, my range is 24+ nautical miles.

image.png

 
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Kris Cringle

Super Anarchist
2,824
2,290
Final Update:

I am so f*cking happy with this pod drive.

Getting underway is so much easier. No schlepping of the outboard to the stern, no schlepping of batteries, no gasoline smell. Just push a button and turn a switch and power awaits. The hardest part is running the extension cord to the dock to re-charge.

Time to anchor and want a little power to get to the right spot? No worries. reach into cockpit cubby, grab the throttle, and push the handle forward: instant power! No need to crawl back to stern and tilt motor into the water.

Need to get home and punch into a 15+ knot headwind? No worries! Plenty of power.

With a fully charged battery, at 3.5 knots, my range is 24+ nautical miles.

View attachment 507617
This has been fun to follow along. You would have been a real curiosity not that many years ago. Today, this makes perfect sense. Some things are changing quickly, electric being one of them. 

One of the properties I keep an eye on for clients, now becoming a foundation, is going through an electric transformation. 20+ year old house on a lake, on the grid but remote enough that it worries me in foul weather as I glance at my phone to regulate the heating system. Power outages, oil burner fails (despite regular maintenance) and chasing leaks in 550 gallons of aging fuel oil storage. 

I gave them my thumbs up on a solar array investment.

Screen Shot 2022-04-30 at 8.24.11 AM.png

We're doing a complete re-design of the property that includes major changes to everything including heat layouts. 

I took it one step further and suggested a complete conversion including a heat pump boiler for radiant floor heating and battery back up (choosing size/number of days off power, now).

It was time for a whole new oil system anyway. I have them in mind as they are good friends to me and also my own peace of mind in the dead of winter. Win-win. 

I was there yesterday and the crew had removed the boiler, 2 oil tanks and all the related gear. The smell of fuel oil has permeated the concrete floor and surrounding plywood walls (not sure what to do there).

It will be exciting to watch it come together. Not for the masses, yet, but for some, the time is now. 

 

tenn-tom

New member
Final Update:

I am so f*cking happy with this pod drive.

Getting underway is so much easier. No schlepping of the outboard to the stern, no schlepping of batteries, no gasoline smell. Just push a button and turn a switch and power awaits. The hardest part is running the extension cord to the dock to re-charge.

Time to anchor and want a little power to get to the right spot? No worries. reach into cockpit cubby, grab the throttle, and push the handle forward: instant power! No need to crawl back to stern and tilt motor into the water.

Need to get home and punch into a 15+ knot headwind? No worries! Plenty of power.

With a fully charged battery, at 3.5 knots, my range is 24+ nautical miles.

View attachment 507617
We have the same setup as Bull, and I completely agree with his assessment, though I would add one more point - no one has to yell over the sound of the motor. When we take friends out for the day, conversations that started at the dock continue in a normal voice. When the wife and I are leaving or arriving at the dock, no yelling. That alone was worth a big chunk of the difference in cost over an outboard.

 

JTE

New member
Bull, I will be interested to hear about your experience with the eProp feathering prop and the pod drive.  The spirit evo 1.0 is working well with my boat, though I see what you have already learned with your boat and the outboard.  

I don’t take my motor off while sailing but I do rinse and stow it at the dock.  It would be nice to do less when putting the boat to bed.

When I first bought the spirit evo outboard I thought that it would be better to just lock it in one direction and use the remote throttle control.  That has two drawbacks.  When the outboard steering is locked off it makes maneuvering in reverse using the rudder pretty difficult.  The outboard being that far out has a lot of leverage pulling the boat straight back.  I would have thought the water stream blowing back onto the rudder would be more effective but it isn’t.  Not enough to counteract wind blowing the bow around in close quarters of the marina.  We get a bit of wind here often.  Others with outboards in the marina use their outboard steering especially in reverse to make these tight turns.   With the Evo outboard not having a tiller handle and no ability to unlock the steering without removing the battery it is not possible to do this.  The second drawback is the power cable between the outboard and the battery on top of the outboard requires a good bit of clearance from the transom to tilt up the outboard.   With the tiller handle installed (and outboard steering not locked off) I will be able to turn the outboard sideways before tilting it up which will make space for the cable and the tiller handle.

I am converting it to the tiller handle next week.  I will keep the remote throttle control and display and ponder converting to pod this winter.  Sell the outboard to a local (it has made a positive impression on people).  The 1kW motor (3hp) size is right for this boat. 

 

Bull City

Bull City
6,895
2,534
North Carolina
Bull, I will be interested to hear about your experience with the eProp feathering prop and the pod drive.
I will be interested too. The things were supposed to ship in April, but so far just blah, blah, blah from the dealer. Assuming I get it within the next couple of months, it will probably be September/October before I haul out to install it.

As to your situation with the Spirit OB, it's possible that a different OB bracket might solve the problem. I had a Trac 0051 with my Torqeedo, like this one. It worked fine.

TRAC 0051 photo.jpg

 
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