Oceanvolt Hybrid Motor

[DumnMad]

Originally Posted by valhalla360

I guess you have a statistically unusual amount of "misinformation" in your posts as you really do appear to believe in magic electric HP.

A bit of magic if you can do away with the weight of the motor + gearbox and replace lower weight in LiFePO4 + electric.

[rabbi]

Originally Posted by BigBeakie

The Vendee rule is that every boat must be able to motor at hull speed for 8 hours, in case of emergency like dismasting. So the answer to your question is yes. He has no fossil fuel generator, but maybe he'll have fuel cell tech as well? Dunno.

FYI, in the last Vendee globe Conrad Coleman was dismasted in the southern Atlantic and lost his solar and made it back to finish the race on only the Oceanvolt regeneration and his jury rigged boom. That's over 2,000 NM keeping the boat electronics, comms and watermaker going on the regen alone. He did not use the SD15 as a motor or break the seal on his generator, & therefore was not disqualified. A helluvan achievement, if you ask me.

If you allowed them to get rid of their engines (and thus weight), how many of these racers would drop it in an instant?
So much for safety considerations.


So they have to be able to motor 25nm.

Your point was

I thought this was a significant announcement, particularly for those who may have commented in the past on the reliability of good EP.

whilethis announcement says exactly nothing about reliability of good EP. Or anything else. You are magically reading between the lines.


Carbon ceramic brakes are used on racing cars and expensive toys for the rich. Which doesn't make them a smart choice for mom's toyota.



Can you show me 20 publicly available reports of normal OV installations that have been cruised a few thousand miles? Happy cruisers sharing stories, Blogs, Vlogs, long term gear test by cruisers. Whatever.


I want to believe in EP. I really do. But the mix of physics, electrical magic, and mixed reports of reliability really make this impossible.

[ssmoot]

Originally Posted by rabbi

while this announcement says exactly nothing about reliability of good EP.

Maybe it's misplaced faith, but I would worry most about installation (adequate cooling of motor controllers?) and battery capacity/hours curve in an OV system before the motor itself, and I'd have more faith that it would be available when I needed it as long as I could power it.

Considering the battery capacity issues with the Nissan Leaf, and that the battery bank of a hybrid boat might be exposed to similar or higher C-rates, and no boat battery bank I'm aware of has active cooling, my primary concern in an EP system would be battery longevity. Chargers and loads are much smaller than in an EV, but so are the banks, so similar per-cell rates, but if charging from a DC generator an individual cell might actually see rates closer to DC Fast Charging, which is not something you want to be doing very frequently in an EV for the best battery longevity and will absolutely wreck a bank (halving-ish capacity) that isn't actively cooled in perhaps as little as 1,500 hours.

Which might be an argument for small AC Generators and 48V/30a charging if you want to maximize battery life. I guess time will tell. It would be neat if one of the vendors published some detailed reports on this.

Originally Posted by rabbi

Can you show me 20 publicly available reports of normal OV installations that have been cruised a few thousand miles? Happy cruisers sharing stories, Blogs, Vlogs, long term gear test by cruisers. Whatever.

That seems like a very reasonable request to make of OceanVolt at this point. I'm not sure I'd expect an individual owner to have access to that many testimonials off-hand.

[DumnMad]

Originally Posted by rabbi

Can you show me 20 publicly available reports of normal OV installations that have been cruised a few thousand miles? Happy cruisers sharing stories, Blogs, Vlogs, long term gear test by cruisers. Whatever.

I want to believe in EP. I really do. But the mix of physics, electrical magic, and mixed reports of reliability really make this impossible.

There are thousands of reports where fossil fuel engines have failed to cruise 50 miles once they hit open waters.
There are large reliability surveys showing owner satisfaction with EV way above ordinary motors.

Believe in EP - its not hard. Just not so practical for heavy boats with existing big engines that are working well.

[svReality]

Hi

We had first sea trials for the SD15 with servoprop.

We achieved 8.5knots at 15kw, and 7knots at 7.5kw. This compares to the previous 54hp yanmar diesels achieving about 8.5knots at 2800rpm. This was in calm seas and river estuary with true wind of about 5knots

With the generator running we can maintain the battery state of charge whilst getting around 7 knots.

Sorry for the poor photos.

Next week we will get the new sails on and test the regeneration.

[Mark424]

Originally Posted by svReality

Hi

We had first sea trials for the SD15 with servoprop.

We achieved 8.5knots at 15kw, and 7knots at 7.5kw. This compares to the previous 54hp yanmar diesels achieving about 8.5knots at 2800rpm. This was in calm seas and river estuary with true wind of about 5knots

With the generator running we can maintain the battery state of charge whilst getting around 7 knots.

Congratulations, it's fantastic to have real world numbers, rather than speculation. Could you give a summary of the boat and system specs? From your other post, 2007 Leopard 46. Any idea what she displaces these days, especially w/ mods?

What generator(s) are you running and what is the power output to sustain you at 7 knots? (e.g. I assume it's 7.5Kw to both SD15s, one 15kw genny? any system losses?) That's really great, and means you could go long range on generator power and only really need enough batteries for house loads, short term electric only runs, speed boost, etc.

Any other special equipment to make the generator, batteries, SD15s all play nice in all the different operational modes?

I'd also be curious of the difference in performance between running just one SD15 at full power vs using the same power split to both sd15s.

Thanks, and congrats on the progress.

Mark

[BigBeakie]

Thanks Reality. Will be great to hear your regen numbers on a beam reach.

Following to hear what others think of your numbers 👍


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[bluenomads]

Originally Posted by Mark424

Congratulations, it's fantastic to have real world numbers, rather than speculation. Could you give a summary of the boat and system specs? From your other post, 2007 Leopard 46. Any idea what she displaces these days, especially w/ mods?

What generator(s) are you running and what is the power output to sustain you at 7 knots? (e.g. I assume it's 7.5Kw to both SD15s, one 15kw genny? any system losses?) That's really great, and means you could go long range on generator power and only really need enough batteries for house loads, short term electric only runs, speed boost, etc.

Any other special equipment to make the generator, batteries, SD15s all play nice in all the different operational modes?

I'd also be curious of the difference in performance between running just one SD15 at full power vs using the same power split to both sd15s.

I'm very interested in the answers too!

Really good to have someone who's walking that walk with the numbers. I've had an initial evaluation from OV and need to do some more talking before we decide (50' power cat).

Given it's 7.5kW to each motor as input (not prop output I assume), then you'd need a genny of continuous rating of 15kW (ignoring losses) which probably means one sold as a 20kW/22kW.

I assume AC genset? I'm thinking a DC may be our direction.

M&M suggest the Leopard 46 is 15,000kg, whereas sailboatdata shows 11,000kg which seems to be its "unladen weight" although that's a huge difference and must be without liquids as well as sails and even maybe mast & rigging.
I couldn't find a w/l length:beam ratio, but I would think about 8:1 perhaps?

[svReality]

hi Bluenomads and Mark424
The generator is a Fischer Panda AGT-DC 15000-48v so 15kw. We looked at going the next size up but felt that 15kw would be enough for what we need 95% of the time.

these are the L46 specs that I used
Loa 46.33 ft., 14.12 m
Lwl 44.58 ft., 13.59 m
Boa 24.83 ft., 7.57 m
Bcl 19.17 ft., 5.84 m
Bh 5.67 ft., 1.73 m
Disp.
14996.85 kg
SA 1593 sq. ft., 147.99 m2
Bcl/Lwl .43
Lwl/Bh 7.86

I don't think the displacement has changed significantly. We estimated that the total weight which was removed was probably 100kg more than we put back in and positioned about 2m closer to midships, but this is negligible in a 14t boat. We can have 10 people on board and you won't notice any difference whether they are all sitting on bow or stern

I will only really see what role the 800w of solar panels play in providing power once I can compare day motoring with night motoring.

While there are obviously some losses between generator and engine it is difficult to determine exactly as power fluctuates with wave and boat motion but I am happy with 7knots with generator and i think it compares favourably with our previous performance under diesel.

Other equipment
motor controllers
charger/inverters
various other bits to link the existing 12v house system to the 48v battery storage system

[bluenomads]

Thank you svReality!

Great to have real numbers. More interesting discussion to be had with the Australian OV rep soon!

Very interested to hear whether solar makes a difference - we'd be expecting our planned 2.5kW array (mostly unshaded) to make a nice difference.

BTW, the Bh number seems off - 1.73m at waterline seems like really fat hulls. I thought the Leopard 46 was quite svelt at the w/l but increased in volume a lot above it? This could improve the lwl:bwl? Or have I mis-read Bh?

7kn continuous is great I think.

Do you have any feelings yet on how wind or wave will/can effect the speed/power mix?

[valhalla360]

Originally Posted by svReality

hi Bluenomads and Mark424
The generator is a Fischer Panda AGT-DC 15000-4......

Thanks for the real world numbers.

15kwx2 is about 40hp.

The yanmars at 2800rpm are each generating about 20hp (40hp total).

8.5kts from 40hp on a 46' cat in calm conditions is pretty normal.

So very consistent with the idea that if you are willing to give up the extra power for tough conditions, you can do it.

Of course, 106HP (total) for a 46' cat is probably a little heavy on HP to begin with.

Good first data point. Please continue to share as you get experience in other conditions.

Any idea on how the overall cost compares to simply repowering with 30-40hp diesels?

[BigBeakie]

When I looked at the FP AGT DC 15000 for our system, I found that there were greater losses with the Fischer Panda genset than I would have hoped. There is a continuous output rating at full temperature that is a fair percentage down on the 15kW. For example the 12kW AGT 12000 put out a measured 8.4kW on another OV installation here. Not sure where the missing 3.6kW go?

So we opted to go with an Oz built milspec brand ( also less expensive than the FP which always helps) nominally rated at 16kW that has a guaranteed continuous output of 15kW output to the batteries at full operating temperature. It is based on a Yanmar 3YM30AE.





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[yvest]

Originally Posted by svReality

Hi

We had first sea trials for the SD15 with servoprop.

We achieved 8.5knots at 15kw, and 7knots at 7.5kw. This compares to the previous 54hp yanmar diesels achieving about 8.5knots at 2800rpm. This was in calm seas and river estuary with true wind of about 5knots

With the generator running we can maintain the battery state of charge whilst getting around 7 knots.

Sorry for the poor photos.

Next week we will get the new sails on and test the regeneration.

Thanks for that, upthread JaJapami mentions that on his set up, he can connect the generator output directly to the electric engine (not sure if only to one engine or two).

Is it also the case for your set up or not ?

And if yes, is the reason the fact that this avoids some loss due to going through the batteries, or also due to the fact that it also preserves the batteries lifespan ?

Basically my question is : having at the same time a high charge load on the batteries from the generator, and a high drain load from the engine, will it shorten the batteries lifespan, or does it not have any real impact on this aspect ?

[StuM]

Originally Posted by yvest

Thanks for that, upthread JaJapami mentions that on his set up, he can connect the generator output directly to the electric engine (not sure if only to one engine or two).

Is it also the case for your set up or not ?

And if yes, is the reason the fact that this avoids some loss due to going through the batteries, or also due to the fact that it also preserves the batteries lifespan ?

Basically my question is : having at the same time a high charge load on the batteries from the generator, and a high drain load from the engine, will it shorten the batteries lifespan, or does it not have any real impact on this aspect ?

Electrickery doesn't work like that. Batteries are either charging or discharging and the "load" on the battery is just the difference between the available charging Watts and the Watts drawn by the equipment. (You don't have separate sets of input and output terminals on opposite sides of the battery with all current flowing between them).

[ssmoot]

Originally Posted by svReality

We achieved 8.5knots at 15kw, and 7knots at 7.5kw. This compares to the previous 54hp yanmar diesels achieving about 8.5knots at 2800rpm.

Clearly you don't know how to read your boat speed display. It's impossible for 30kW worth of electric motors to perform similarly to 76kW (Yanmar 4JH5E produces about 38kW at the crank at 2800RPM) worth of diesel.

Because that would be "magical thinking" as has been clearly stated so many times here before.

(maybe not so obvious sarcasm)