Torqeedo Cruise 4.0 Electric Outboard

[GrowleyMonster]

My boat is electric (inboard) and I find the Torqueedo line to be a bit expensive. The batteries that they recommend, even more so. My 48v 220ah bank is comprised of 8 6v GC2 golf cart batteries, at $85 each. They are 3-1/2 years old, and not showing any signs of deterioration or loss of capacity. Sure, you can only take them down to about 50% on a routine basis, for decent service life, but I HAVE taken mine down to about 30% a couple of times and no apparent harm done. Of course I do check them regularly, maintain electrolyte level, and equalize a couple times a year, but no biggie. Yeah, fancy batteries are supposed to last longer and allow greater depth of discharge and weigh less. Particularly LiFeP04 batteries. But when I do the math, looks like they still cost 2x to 3x more by any measure, than good old golf cart batts. I know, folks who have drank the coolaid and invested in $10k worth of lithiums go into fits of spluttering rage to read this, but do the math yourself. Don't take it from me. The emperor's new clothes aren't really there. At least not yet. Go Lithium if you have a big budget and you want light weight and basically zero maintenance. And a good BMS that you trust your life to. They are indeed marvelous, just not for the budget minded. Same for AGM. Great for when you need to mount your batteries upside down or something. Or you simply cant remeber to check your batteries once a month. But cost a lot more than golf cart batteries. A LOT more. And Trojans don't seem to actually be any better than Duracell or Eveready from Sams Club, these days, but they sure cost a bunch more. Again, don't take my word for it.

Range is always an issue with electric drive. Go super slow, and you can have surprising range, in decent conditions. Go fast, and you can see with your eyeballs for about twice as far as you can go. Electric really works best for MOST folks, when they only need the motor for short distances. For just maneuvering and docking, wow, it is like a dream. Instant power, very fast reverse, no warmup or startup prayers, no fuel to buy or smell or spill, very quiet, and no minimum idle speed.

Here is an option if you know that you will only need your motor for docking and a very short run to open water: a 20ah 48v LiIon bicycle battery. It is light, and portable, and will give you 5a current easily for a couple of hours. I motored for about 6 miles on one, once, just as an experiment. 27' 7600lb monohull, going dead slow. These packs run about $450 on fleabay shipped free from China, and fit in a small backpack. They have built in BMS, and a fuse or circuit breaker. Only have to go a half mile or so? This might gitter done. You pay an awful lot per watt/hour but you get a lot of convenience and hey, it's not a huge tremendous purchase like a full size bank. Get two, they're small. Actually though I would go with lead golf cart batts. They will treat you as good as you treat them.

As for the motor itself, I think that there are better options. Torqueedo is a finely engineered unit, some would say too finely engineered for real world usage. There seem to be a mixed bag of reviews, not good for an item with a premium price tag. There are other electric outboards probably more worth your consideration. A catamaran, huh? You might even consider a pair of trolling motors, with aftermarket props. You need big ones, certainly not less than 100lbs thrust. Too bad you cant get right hand and left hand models, but that shouldn't be anything you can't cope with. If they are cheapies, without PWM controllers, you will get more efficient use by driving them with an separate PWM controller (a Chinese 48v 20a controller shouldn't cost more than $40 or so) and leaving the trolling motor speed control in full power position. Use a $1 potentiometer connected to the controller throttle input for speed control, or get a fancy throttle for $50 or so. The big qestion with trolling motors is will a pair of them give you the speed you crave. Me, I don't crave speed. When I am on my boat, I am already at my destination. But some people just have to hurry up and get somewhere and I almost sort of understand that, maybe, I think. But I suspect a pair of 36v trolling motors will push your cat surprisingly well, and cheaply. google for Newport Vessels trolling motors. Fresh or salt water, inexpensive. Way less than Minn Kota and the like.

[yvest]

Originally Posted by myocean

Until now this feature is not officially implemented in the Cruise 4.0 Outboard but just in the pod drive. However technically this is very well imaginable and Torqeedo is considering to officially qualify and offer this in future. Mechanical stress on the outboard leg is an issue regarding this.
But as far as I am informed, it works inofficially already now: Move the remote throttle just a little bit ahead and if the boat is moving sufficiently fast, hydrogeneration should start. Don't break it!

You might be interested in the new Torqeedo 48-5000 lithium battery. 48V/5kWh/36kg, using BMW i-series modules. Most importantly this battery will take a lot more cycles than many other lithium batteries. Up to 3500 cycles (100%) with a capacity loss of less than 20% can be expected from this heavy duty product at reasonable ambient temperatures. Price tag: 4999 EUR.

In general please be careful with low cost lithium batteries. Look for high quality cells, a very good, tested and qualified battery management system and a water resistant housing.

Thanks a lot for the info, and indeed the mechanical stress aspect could get tricky, and will follow this battery closely, what chemistry is it ? LifePO4 or something else ?

[yvest]

@myocean

By the way do you know if an outboard in between the 4 and 10 is planned ?
This is quite a big gap, and for my project one in between (6 or 7) would be much better.

[SailFastTri]

Originally Posted by GrowleyMonster

My boat is electric (inboard) and I find the Torqueedo line to be a bit expensive. The batteries that they recommend, even more so. My 48v 220ah bank is comprised of 8 6v GC2 golf cart batteries, at $85 each. They are 3-1/2 years old, and not showing any signs of deterioration or loss of capacity. Sure, you can only take them down to about 50% on a routine basis, for decent service life, but I HAVE taken mine down to about 30% a couple of times and no apparent harm done. Of course I do check them regularly, maintain electrolyte level, and equalize a couple times a year, but no biggie. Yeah, fancy batteries are supposed to last longer and allow greater depth of discharge and weigh less. Particularly LiFeP04 batteries. But when I do the math, looks like they still cost 2x to 3x more by any measure, than good old golf cart batts. I know, folks who have drank the coolaid and invested in $10k worth of lithiums go into fits of spluttering rage to read this, but do the math yourself. Don't take it from me. The emperor's new clothes aren't really there. At least not yet. Go Lithium if you have a big budget and you want light weight and basically zero maintenance. And a good BMS that you trust your life to. They are indeed marvelous, just not for the budget minded. Same for AGM. Great for when you need to mount your batteries upside down or something. Or you simply cant remeber to check your batteries once a month. But cost a lot more than golf cart batteries. A LOT more. And Trojans don't seem to actually be any better than Duracell or Eveready from Sams Club, these days, but they sure cost a bunch more. Again, don't take my word for it.

Range is always an issue with electric drive. Go super slow, and you can have surprising range, in decent conditions. Go fast, and you can see with your eyeballs for about twice as far as you can go. Electric really works best for MOST folks, when they only need the motor for short distances. For just maneuvering and docking, wow, it is like a dream. Instant power, very fast reverse, no warmup or startup prayers, no fuel to buy or smell or spill, very quiet, and no minimum idle speed.

Here is an option if you know that you will only need your motor for docking and a very short run to open water: a 20ah 48v LiIon bicycle battery. It is light, and portable, and will give you 5a current easily for a couple of hours. I motored for about 6 miles on one, once, just as an experiment. 27' 7600lb monohull, going dead slow. These packs run about $450 on fleabay shipped free from China, and fit in a small backpack. They have built in BMS, and a fuse or circuit breaker. Only have to go a half mile or so? This might gitter done. You pay an awful lot per watt/hour but you get a lot of convenience and hey, it's not a huge tremendous purchase like a full size bank. Get two, they're small. Actually though I would go with lead golf cart batts. They will treat you as good as you treat them.

As for the motor itself, I think that there are better options. Torqueedo is a finely engineered unit, some would say too finely engineered for real world usage. There seem to be a mixed bag of reviews, not good for an item with a premium price tag. There are other electric outboards probably more worth your consideration. A catamaran, huh? You might even consider a pair of trolling motors, with aftermarket props. You need big ones, certainly not less than 100lbs thrust. Too bad you cant get right hand and left hand models, but that shouldn't be anything you can't cope with. If they are cheapies, without PWM controllers, you will get more efficient use by driving them with an separate PWM controller (a Chinese 48v 20a controller shouldn't cost more than $40 or so) and leaving the trolling motor speed control in full power position. Use a $1 potentiometer connected to the controller throttle input for speed control, or get a fancy throttle for $50 or so. The big qestion with trolling motors is will a pair of them give you the speed you crave. Me, I don't crave speed. When I am on my boat, I am already at my destination. But some people just have to hurry up and get somewhere and I almost sort of understand that, maybe, I think. But I suspect a pair of 36v trolling motors will push your cat surprisingly well, and cheaply. google for Newport Vessels trolling motors. Fresh or salt water, inexpensive. Way less than Minn Kota and the like.

Good answer, good insight and information. This whole electric power thing is an elusive holy grail, and your post confirms that it can be workable for someone who doesn’t want to go far or fast. But it’s a big limitation for people who may need to motor for long distances or (timely) make safe port in the calm before a storm.
It’s a also much heavier and costly approach than internal combustion drive engines when you consider battery weight (and especially if you add a generator for battery charging). Not desirable to have the extra weight on a multihull.
Dick at Maine Cat tried to convince me the Torqeedo is the right approach in the Maine Cat 38 and I couldn’t get past the fact that you just can’t Motor all day in a dead calm or headwinds when you can’t sail and need to move the boat somewhere at a reasonable speed.

[Sparx]

At last count 40-50% of the new Maine Cat 38s on order have selected the
Torqeedo based electric propulsion system. These boats feature a pair of Torqeedo Cruise 4.0 FP pod drives with folding two bladed propellers.
Maine Cat 38 - Maine Cat Catamarans

I am hearing these boats have a >250 mile range at cruising speed on a single charge, and the system regenerates power when sailing. Addition recharge capability is provided by a powerful solar array, shore power and an optional generator.

Suggest calling Maine Cat if you are serious about the concept. I expect they will be willing to share some insights.

[skipmac]

Originally Posted by Sparx

I am hearing these boats have a >250 mile range at cruising speed on a single charge,

Wherever you heard this is very misinformed. That range is impossible based on the published specs for the Maine Cat at the link you posted. Specs say 10,740 Watt hours battery capacity. The Torquedo 4.0 is rated at 4000 Watts, two on the boat. Even running each motor at 25% power you will run the batteries down to zero from full charge in just over 5 hours. Doubt 25% power would run at much more than very slow in any real world conditions but assuming 5 kts that's a range of 50 miles.

[skipmac]

Originally Posted by skipmac

Wherever you heard this is very misinformed. That range is impossible based on the published specs for the Maine Cat at the link you posted. Specs say 10,740 Watt hours battery capacity. The Torquedo 4.0 is rated at 4000 Watts, two on the boat. Even running each motor at 25% power you will run the batteries down to zero from full charge in just over 5 hours. Doubt 25% power would run at much more than very slow in any real world conditions but assuming 5 kts that's a range of 50 miles.

Just found the Torquedo advertised on Westmarine. With half the batteries spec'd for the Maine Cat it shows a 10 hour, 29 mile range at 2.7 kts. Seems like my guestimate wasn't far off.

To get 250 mile range you would have to increase the battery bank on the Maine Cat by a factor of 5 so 20 of the 24V 26-104 lithium batteries that list for $2600 each or over $50,000 worth of batteries weighing over 1000 lbs. Think I'll stick with diesel for now.

[SailFastTri]

Originally Posted by Sparx

At last count 40-50% of the new Maine Cat 38s on order have selected the
Torqeedo based electric propulsion system. These boats feature a pair of Torqeedo Cruise 4.0 FP pod drives with folding two bladed propellers.
Maine Cat 38 - Maine Cat Catamarans

I am hearing these boats have a >250 mile range at cruising speed on a single charge, and the system regenerates power when sailing. Addition recharge capability is provided by a powerful solar array, shore power and an optional generator.

Suggest calling Maine Cat if you are serious about the concept. I expect they will be willing to share some insights.

I'd love to see the math behind that claim. Then again, perhaps it depends on how you define "cruising speed"... (In my mind, a leisurely "cruising speed" under power on a narrow-hulled 38' cat should be somewhere in the range of 6-7 knots.)

You've got to read the specs on the motors with regard to power consumption and/or regeneration, and the size of battery banks, solar capability and the output of small generators like that. Then do the math and think about how much power a 38 foot cat needs to cruise at "cruising speed".

Maine Cat is also talking dichotomies when they tout great sailing performance, and also electric regeneration using fixed (non-folding non retractable) props and electric motors. (That's equivalent to dragging two drogues.) Pretty hard to be fast when the brakes are always on. The faster ones are the ones built with electric outboards, which can be retracted.

[SailFastTri]

Originally Posted by skipmac

Just found the Torquedo advertised on Westmarine. With half the batteries spec'd for the Maine Cat it shows a 10 hour, 29 mile range at 2.7 kts. Seems like my guestimate wasn't far off.

To get 250 mile range you would have to increase the battery bank on the Maine Cat by a factor of 5 so 20 of the 24V 26-104 lithium batteries that list for $2600 each or over $50,000 worth of batteries weighing over 1000 lbs. Think I'll stick with diesel for now.

I saw your post after I posted mine, above. You are the voice of reason. I think people who have drunk the cool-aid about electric propulsion for cruising boats are more in love with the concept than the reality. I solute the dreamers and pioneers, and hope we get there some day.

Right now it doesn't add up for small boats unless they are used infrequently for short periods/distances, and allowed time to recharge between uses.

[myocean]

Originally Posted by yvest

Thanks a lot for the info, and indeed the mechanical stress aspect could get tricky, and will follow this battery closely, what chemistry is it ? LifePO4 or something else ?

This is NMC chemistry with prismatic cells.

Originally Posted by yvest

@myocean
do you know if an outboard in between the 4 and 10 is planned ?
This is quite a big gap, and for my project one in between (6 or 7) would be much better.

No plans.

[skipmac]

Originally Posted by SailFastTri

I saw your post after I posted mine, above. You are the voice of reason. I think people who have drunk the cool-aid about electric propulsion for cruising boats are more in love with the concept than the reality. I solute the dreamers and pioneers, and hope we get there some day.

Right now it doesn't add up for small boats unless they are used infrequently for short periods/distances, and allowed time to recharge between uses.

Unfortunately correct in all the above. Lots of people in love with concept but don't understand the realities. I am definitely in love with the concept and would love to go electric but to do so and keep a decent cruising range under power (which I define as at least 250-300 miles) the only answer currently is to install a diesel generator to power the electric motor.

So now you removed the engine and replaced it with a more complex, more expensive engine generator. Have done the financial math as well as the power math many times. It still adds up to double or triple the cost of a brand new diesel engine to go with electric plus generator.

[barrymac]

Recently got one of these for my tender with Torqeedo batteries and loving it so far. Extremely quiet and incredibly precise control, and it just works. No worries for weaker crew members to start it, and it planes the dinghy (2.9m aluminium RIB) no problem with one person.

Not to say there are no problems, just that I prefer the new problem set better than the old one with the petrol outboard which was heart and back breaking.

Scary amount of power in those batteries though they need to be well protected from weather and being 48v system will conduct easily through wet rope and what not. Building a glass box for them, with a charging extension cable to get to chargers on board main boat.

I did love the throwing away my box of spares; spark plugs, impellers, carburetors, fuel tanks, two stroke oil etc!

Suits me particularly well because I'm not able to use a traditional outboard often enough to keep it going well.

[GrowleyMonster]

Originally Posted by Sparx

At last count 40-50% of the new Maine Cat 38s on order have selected the
Torqeedo based electric propulsion system. These boats feature a pair of Torqeedo Cruise 4.0 FP pod drives with folding two bladed propellers.
Maine Cat 38 - Maine Cat Catamarans

I am hearing these boats have a >250 mile range at cruising speed on a single charge, and the system regenerates power when sailing. Addition recharge capability is provided by a powerful solar array, shore power and an optional generator.

Suggest calling Maine Cat if you are serious about the concept. I expect they will be willing to share some insights.

I just re read this post and wow... folding props on an electric drive system, on a 48 foot cat? Doesn't make sense. With folding props, regen is not possible. Regen is not even worth worrying about, for say a 30 foot cruising monohull. For a 48 foot catamaran, regen could be significant if she is sailed hard in a good breeze. I would want fixed two blade props. Secure the shafts with the prop blades vertical, for less drag, or apply just enough current for zero drag, or charge batteries via regen with maybe a quarter knot speed loss. Well, probably closer to a half knot, with twin screws. Anyway such a boat is fast enough, potentially, to enable significant regeneration, and it would be silly to not have the ability to do so. Also, folding props are probably inefficient compared to fixed props, when motoring. Okay, so it is a sailboat, and sailboats are made to be sailed and not motored. Sure, I get that. I live that. But folding props for such a boat should be only an option. I would go with the biggest 2 blade prop that can be swung under the hull.

[SailFastTri]

Originally Posted by barrymac

Recently got one of these for my tender with Torqeedo batteries and loving it so far. Extremely quiet and incredibly precise control, and it just works. No worries for weaker crew members to start it, and it planes the dinghy (2.9m aluminium RIB) no problem with one person.

Not to say there are no problems, just that I prefer the new problem set better than the old one with the petrol outboard which was heart and back breaking.

Scary amount of power in those batteries though they need to be well protected from weather and being 48v system will conduct easily through wet rope and what not. Building a glass box for them, with a charging extension cable to get to chargers on board main boat.

I did love the throwing away my box of spares; spark plugs, impellers, carburetors, fuel tanks, two stroke oil etc!

Suits me particularly well because I'm not able to use a traditional outboard often enough to keep it going well.

Maybe you should carry a spare in the form of inexpensive trolling motor, for when that Torqeedo has a problem and there’s no way to fix it locally.