Oceanvolt Hybrid Motor

[Jim Cate]

Ya know, we've been seeing these arguments for a long time now. The enthusiasts just know it is gonna work, the naysayers say nay, the engineers run numbers to support whatever theory is uppermost in their minds...

As for me, I'm just gonna sit back and wait to see the successful, or unsuccessful vessels that are put together by the enthusiasts. If they work as well as imagined, I'll be impressed and thinking about future changes. If they work as I imagine, we will likely not hear very much about them, and it will be another broken dream and damaged bank account.

But all this theoretical argument is getting tiresome to me; I await some empirical data from real boats.

Jim

[StuM]

Originally Posted by DaveWalters

Technically that is how it is measured.
Just like the kW vs kWh you are nitpicking about.

On that topic,seeing as you are so uptight about nomenclature you ought to notify Cummins and tell them they are doing it wrong:

You are being redirected...

Yanmar too:

https://www.yanmar.com/global/genera...el_generators/

And virtually every generator dealer out there:
7-33 kW Diesel - Hardy Diesel's & Equipment Inc * Diesel Generators

I don't see any "h" after the kW, better get on that.

Of course not, you're the one that erroneously included the "h" in your posting. Nice to see that all of your own references confirm that you were wrong.

Just as you incorrectly put the nonsensical "/h" after HP.

[valhalla360]

Originally Posted by Jim Cate

Ya know, we've been seeing these arguments for a long time now. The enthusiasts just know it is gonna work, the naysayers say nay, the engineers run numbers to support whatever theory is uppermost in their minds...

As for me, I'm just gonna sit back and wait to see the successful, or unsuccessful vessels that are put together by the enthusiasts. If they work as well as imagined, I'll be impressed and thinking about future changes. If they work as I imagine, we will likely not hear very much about them, and it will be another broken dream and damaged bank account.

But all this theoretical argument is getting tiresome to me; I await some empirical data from real boats.

Jim

There's really no new technology being discussed and various electric systems have been tried. Probably 20yrs ago one of the big cat manufacturers tried it and it flopped with most being converted to standard diesel.

Theoretical and empirical match up quite nicely once you get past the marketing hype (ie: compare apples to apples).

Yeah, I could build a 45' cat that would go 7kts on 7kw. Of course, it comes with major limitations and you could achieve the same performance with a pair of 5hp diesels (which is pretty close to 7kw). The reason you don't see 5hp diesels specified for a real life 45' cat is because the design compromises to hit that level of performance (7on7) makes the boat unacceptable for the vast majority of cruisers. It would have very limited accommodations, minimal load capacity, it would be so light that capsize (assuming a sailboat) starts becoming a real concern unless you drastically under power the sail plan, you would have hulls so narrow that stuffing a bow into a wave and tripping over it becomes a risk...but if all you care about is 7kts on 7kw, it can be done.

[StuM]

Wonder how many HP / kW this guy is using

http://www.cruisersforum.com/forums/...ml#post2247092

[44'cruisingcat]

Originally Posted by Jim Cate

Ya know, we've been seeing these arguments for a long time now. The enthusiasts just know it is gonna work, the naysayers say nay, the engineers run numbers to support whatever theory is uppermost in their minds...

As for me, I'm just gonna sit back and wait to see the successful, or unsuccessful vessels that are put together by the enthusiasts. If they work as well as imagined, I'll be impressed and thinking about future changes. If they work as I imagine, we will likely not hear very much about them, and it will be another broken dream and damaged bank account.

But all this theoretical argument is getting tiresome to me; I await some empirical data from real boats.

Jim

I felt I posted empirical data that suggested 7 knots from 7 kW would be well out of reach for a 13 tonne boat.

[Jim Cate]

Originally Posted by 44'cruisingcat

I felt I posted empirical data that suggested 7 knots from 7 kW would be well out of reach for a 13 tonne boat.

es, I'd say somewhat lighter alright. We weigh around 6 tonnes all up, LWL 13.5 m and LWL:BWL around 12.5 : 1.

And we can't do 7 knots on 7 kW. Probably more like 5 knots.

First thing, 44, is that I agree with your statements. But to me, what you posted isn't empirical data for the putative 7/7 boat... it is an estimate based on unproven similarity between your boat and the 7/7 dream.

But I do agree with your conclusion... until proven wrong!

Jim

[cwjohm]

Forgetting about 7/7 which is plainly ridiculous, it is very hard to get empirical data from owners of boats where the electrics have been ripped out in favour of diesels.

In three cases I know of the sea trials were fine (the electrics were appropriately sized as compared to the fanciful notions entertained in this thread), the sea trials being conducted in sheltered areas and flat seas, but once the vessel put to the open ocean and encountered typical sea conditions which required sustained and powerful motoring the owners immediately returned to base to get refits.

Attempting to get empirical data in these instances is difficult as the owners in question were not really forthcoming in admitting what was a very expensive mistake, and invariably a very harrowing experience.

In general however, I agree with Jim that this subject has been thrashed to death on this forum. There will always be the true believers trying to push the boundaries, and at some time in the future electric will actually work for the cruising cat. When that happens the proof will be empirically evident and the cruising community will embrace it with gusto. It is simple an argument on the timeframe. My view is we are probably at least a decade away.

[Cotemar]

This marine electric motor technology just needs more time and early adapters to get it rolling.
.
I will go just a bit off track and talk about electric lawn mowers to get the point across.
.
Electric lawn mowers went from 12 to 24 to 36 to 40 to 48 to 50 to 80 volts.
.
They all SUCKED before they got to 80 Volts.
.
I bought one of these Greenworks GLM801602 Pro 80V Cordless Lithium-Ion 21 in. 3-in-1 Lawn Mower with a GBA80400 80V 4.0 Ah Lithium-Ion Battery and fast charger for $500 at the beginning of this year.
.
The 80 volt 4.0 Ah Lithium-Ion battery fully charges in 30 to 45 minutes.
.
I mow my whole 137 x 78 feet lot and then take the battery out and weed whack the whole lot all on one charge.
.
It is maintenance free, no oil or gas or belts. Folds up and tucks in the corner of my garage.
.
Its whisper quiet and lightweight.
.
This was not even possible just last year.

[44'cruisingcat]

Trouble is, finding a powerpoint to plug the boat into...

[Redreuben]

The electric tech is plenty adequate as it is, the weak link is simply energy storage, when batteries approach the energy density of diesel everything on board can be electric powered. It will come. Five years I reckon, if that.
The market is huge because of what it can do for cars, there is lots of money and time being thrown at it, we just have to wait.

[valhalla360]

Originally Posted by Cotemar

This marine electric motor technology just needs more time and early adapters to get it rolling.
.
I will go just a bit off track and talk about electric lawn mowers to get the point across.
.
Electric lawn mowers went from 12 to 24 to 36 to 40 to 48 to 50 to 80 volts.
.
They all SUCKED before they got to 80 Volts.
.
I bought one of these Greenworks GLM801602 Pro 80V Cordless Lithium-Ion 21 in. 3-in-1 Lawn Mower with a GBA80400 80V 4.0 Ah Lithium-Ion Battery and fast charger for $500 at the beginning of this year.
.
The 80 volt 4.0 Ah Lithium-Ion battery fully charges in 30 to 45 minutes.
.
I mow my whole 137 x 78 feet lot and then take the battery out and weed whack the whole lot all on one charge.
.
It is maintenance free, no oil or gas or belts. Folds up and tucks in the corner of my garage.
.
Its whisper quiet and lightweight.
.
This was not even possible just last year.

Totally different issue with lawn mowers. A 12v motor of the same HP is much larger than an 80v motor. A push mower needs a small lightweight motor because some poor schmuck has to push it around.

On a 30-50' cruising boat the weight difference between voltages available has negligible impact on the end result as an extra 20-50lbs saved doesn't make much difference to the overall weight of the boat. I know one of the early failed designs used 144v DC, so it's already been thought of.

FYI - it was entirely possible just last year but no one had bothered.

[Cotemar]

If your generator is putting out 230-240 volts AC.
Then that is what the electric motors should be.

[transmitterdan]

Originally Posted by Redreuben

The electric tech is plenty adequate as it is, the weak link is simply energy storage, when batteries approach the energy density of diesel everything on board can be electric powered. It will come. Five years I reckon, if that.
The market is huge because of what it can do for cars, there is lots of money and time being thrown at it, we just have to wait.

I would add one more requirement and that would be that the onboard battery should be refilled in about the same time frame as the diesel tanks. It would be a problem to have giant batteries that take days and days to recharge. Diesel has 40kwh per US gallon. Assuming that electric drives would use 1/2 that then the recharge rate would have to be something on the order of 200kwh per minute. That requires a charging system capable of 12 million watts. Probably that will never happen.

[Cotemar]

Tesla is so successful because they are using 300+ volt 3-Phase 4-Pole AC Induction Motors.

A 48 volt Oceanvolt Motor is just a toy at the moment.

Once Oceanvolt gets up to 240 volts AC induction, they will get out of BETA testing stage.

[ranchero76]

BTW, there's guy who hacked Tesla motor, made it spinning from DIY controller. This would make perfect hybrid.