Jimmy Cornell goes Electric, with a Cat

[mikedefieslife]

Originally Posted by Yihang

I need to rewatch some of umas videos as well but i think even they didnt have full batteries after the atlantic crossing. My guess is no one until now really rested regen over long diatances and like jimmy said smooth test sails are not reliable.

They didn't have any regen, and don't really have much solar either.

It's only when they got their new sail drive did they get regen IIRC.

They did a test of it from Netherlands to Norway.

Cornell just needed more solar, and possibly dedicated hydro generators. Even a couple of watt & sea 600s would have done him well at 8knts boat speed.

[fxykty]

Originally Posted by mikedefieslife

They didn't have any regen, and don't really have much solar either.

It's only when they got their new sail drive did they get regen IIRC.

They did a test of it from Netherlands to Norway.

Cornell just needed more solar, and possibly dedicated hydro generators. Even a couple of watt & sea 600s would have done him well at 8knts boat speed.

For Cornell’s fast trip around the world dedicated hydro-gen like the Watt & Sea would be great. But they’re really expensive, especially as he would have to get the racing version with the variable prop. We looked at it for our boat, and because we can easily surf to 20+ knots from an average speed of 8-9 knots in big waves the regular prop options won’t work. The O45 would have a similar issue. But if regen from the engines isn’t working that would be the only option on passages.

For regular cruising where you get to a destination area and spend some time sitting and short-hopping, you need mainly passive sources. Cabin tops are usually good places, as when you’re anchored you just swing the boom out of the way. Even on the O45 there’s enough room on the bimini top and cabin for a kW or so.

Aren’t there panels that you can walk on? Are they non skid? If so, put them on the bows and other lightly trod areas of the deck.

I saw somewhere a reference to a solar blanket, that you unfold and use as a sunshade when anchored. I can imagine a large rectangular shade tent that is covered in solar panels, providing a heap of power when anchored.

Success is built on prior failures. I’m looking forward to the next attempt.

[myocean]

I wonder why OceanVolt has not sent their engineers. Their adjustable prop hydrogeneration is said to be excellent and should indeed deliver a lot more energy. (Torqeedo has no such sophisticated adjustable prop system but generates at least more energy than Cornell is reporting here)

Reading about these results I wonder if this has all been fake marketing from Oceanvolt (I don't think so) or if the OceanVolt management has been incapable to realize that putting efforts in making THIS customer happy is the ultimate key to success. What else could be the reason? Strange...

[harlem24]

They even had a guy in Holland when Umas drive didn't work.
Strange.

[mglonnro]

Originally Posted by BigBeakie

The report from Cornell raises questions re the data, in my mind. If he has one SD15 and one Servoprop, why does he expect only 800 watts at 8 knots, for starters when that is only what the SD15 would output? The output from the Servoprop is about three times that of the SD15.

A technical investigation will take place I'm sure, and then we'll see whats what. I'm reserving judgement until then.

Reading the blog post, it seems like he is talking about net (charging) gain regarding the whole system?

While sailing, the propellers on the two saildrives are turning and producing electricity. I had been assured that we could expect an average charge of 600 Watts at 6 knots and 800 Watts at 8 knots. During the tests carried out at La Grande Motte, where the Outremer boatyard is based in the south of France, we achieved those figures, and I was persuaded.

Our 1000-mile maiden voyage from La Grande Motte to Seville showed up some of the weaknesses of the regeneration system when it failed to keep up with the overall consumption on a proper voyage, not during a test in calm waters. The consumption included both the autopilot and instruments, and also domestic demands such as induction cooker, microwave oven, two fridges, etc. My doubts started after we had sailed 82 miles in a period of 10 hours at an average speed of 8.2 knots. The net gain was a disappointing 9.5% of our total battery capacity, equivalent to 5.32 kWh, or 532 Watts per hour.

So, using AP, instruments, fridges, cookers, etc, he expected average 800W into the batteries and got 532W -- so about 33% less than expected?

It will be interesting to get more details, if the parties involved choose to release them. For Oceanvolt, the blog post and its conclusions are quite terrible

[250224]

https://cornellsailing.com/2020/12/a...ero-journal-8/

He's back and a.o.

"Aventura’s future and that of an electric boat with zero carbon emissions will now be decided, and I shall report on the outcome in my next journal." .. "those lessons will help us decide on the next stage. I am pleased to say that we have completed this long voyage with zero carbon emissions on each of our offshore passages."

[Yihang]

It's going to be hilarious if he starts it again. But he plugged in at the ports so technically the voyage was not zero emissions, I guess he tried to cover that with 'offshore passages' bit, but.....yeh, nah, it failed.

[theDangerz]

Originally Posted by myocean

I wonder why OceanVolt has not sent their engineers. Their adjustable prop hydrogeneration is said to be excellent and should indeed deliver a lot more energy. (Torqeedo has no such sophisticated adjustable prop system but generates at least more energy than Cornell is reporting here)

Reading about these results I wonder if this has all been fake marketing from Oceanvolt (I don't think so) or if the OceanVolt management has been incapable to realize that putting efforts in making THIS customer happy is the ultimate key to success. What else could be the reason? Strange...

This was my biggest takeaway/confusion from the whole story. No way they don't realize the marketing opportunity or the number of eyes watching...

[mglonnro]

Originally Posted by theDangerz

This was my biggest takeaway/confusion from the whole story. No way they don't realize the marketing opportunity or the number of eyes watching...

I still don't really understand the numbers he's reporting. The 800W seems like a regeneration/charging number (something showing on the OV panel), but the "disappointing net gain" of 532W would be a net of (battery in) - (battery out)?

+ 800W regeneration (let's say)
- 268W for instruments, AP
= +532W into the battery

That's not bad?

[harlem24]

They shut everything else down. So not really good. And with a 50kWh battery pack it's still a bit less...
And it's coming from both motors, that would be around 260W from each...
Expactation was I think 800W from each motor.

[250224]

Originally Posted by Yihang

It's going to be hilarious if he starts it again. But he plugged in at the ports so technically the voyage was not zero emissions, I guess he tried to cover that with 'offshore passages' bit, but.....yeh, nah, it failed.

I noticed the 'offshore passages' too... It was well put . But the second you put in the plug in any stop, you can forget about sailing (around the world) without a drop of fuel.

Maybe if he were 20 years younger he'd have a chance to (successfully) start again. Now I think the only thing left to do is to document the exact numbers. (Then buy a genset and enjoy life).

It is very good though that he puts his name/fame on such an endeavour.

[Rennsail]

I was hoping that a reasonably priced, all-electric auxiliary propulsion system would be part of my long-term plans for cruising. However, given experiments like this and the experiences of other "early adopters" like S/Y Top Secret, it is clear to me that a hybrid solution is the only real alternative for the foreseeable future.


Additionally, I am not willing to festoon my boat with multiple pricey inefficient appendages, ration electricity use while cruising and potentially risk my life and that of my crew to make a statement about how "green" my boating may be.


I'm already on sailboat for God's sake and If I have to deploy a single diesel device (motor or genset) it will just have to be "good enough" until technology catches up with the realities of cruising.


P.S. I don't work for an oil company and I currently have a 34 panel solar array on my primary home.

[Yihang]

Originally Posted by Rennsail

I was hoping that a reasonably priced, all-electric auxiliary propulsion system would be part of my long-term plans for cruising. However, given experiments like this and the experiences of other "early adopters" like S/Y Top Secret, it is clear to me that a hybrid solution is the only real alternative for the foreseeable future.


Additionally, I am not willing to festoon my boat with multiple pricey inefficient appendages, ration electricity use while cruising and potentially risk my life and that of my crew to make a statement about how "green" my boating may be.


I'm already on sailboat for God's sake and If I have to deploy a single diesel device (motor or genset) it will just have to be "good enough" until technology catches up with the realities of cruising.


P.S. I don't work for an oil company and I currently have a 34 panel solar array on my primary home.

The hope is on energy density. Current Lifepo4 is around 100wh/kg. Several companies including tesla are saying around 400-500wh/kg in 5 years. current tesla 3 batteries are 260wh/hr.

So in 10 years maybe a 3x increase in battery density for the marine market. That would give you a decent range between ports with superchargers.

Generating your own power for propulsion is a much harder puzzle to crack.

[Dockhead]

Originally Posted by Yihang

The hope is on energy density. Current Lifepo4 is around 100wh/kg. Several companies including tesla are saying around 400-500wh/kg in 5 years. current tesla 3 batteries are 260wh/hr.

So in 10 years maybe a 3x increase in battery density for the marine market. That would give you a decent range between ports with superchargers.

Generating your own power for propulsion is a much harder puzzle to crack.

I wouldn't jump to conclusions -- Teslas use Panasonic 2170's -- Nickel Cobalt Aluminum. We use a totally different technology -- LiFePo4, which has less power density but is much safer for our use case. Advances in NCA technology will not automatically translate into advances in LiFePo4.



We can hope of course. Diesel fuel has about 11.6kWh/kg of power density, so more than two orders of magnitude more than LiFePo4. We've got a long ways to go. I carry about 1000kg of diesel fuel on board my boat -- it would take more than 100 tonnes (!) of LiFePo4 batteries to carry the same amount of energy. Cutting that to 50 tonnes or even 25 tonnes is still a long way from being competitive.

[Yihang]

Originally Posted by Dockhead

I wouldn't jump to conclusions -- Teslas use Panasonic 2170's -- Nickel Cobalt Aluminum. We use a totally different technology -- LiFePo4, which has less power density but is much safer for our use case. Advances in NCA technology will not automatically translate into advances in LiFePo4.



We can hope of course. Diesel fuel has about 11.6kWh/kg of power density, so more than two orders of magnitude more than LiFePo4. We've got a long ways to go. I carry about 1000kg of diesel fuel on board my boat -- it would take more than 100 tonnes (!) of LiFePo4 batteries to carry the same amount of energy. Cutting that to 50 tonnes or even 25 tonnes is still a long way from being competitive.

For sure it will never be competitive with diesel, but in 20 years the choice wont be there.

Companies like Torqueedo are using BMW batteries which are not Lifepo4. They are LiNMC I believe, which is between NCA and Lifepo4. So we are certainly not locked into Lifepo4, at least not in the long term. What chemistry does OV use? The propulsion guys will probably be the test beds for new batteries safe for marine use.

Tesla still haven't released their chemistry yet for the new tabless 4680 batteries but it won't be using cobalt. Certainly a lot of money will be poured into this space from now. Fingers crossed.

A typical 40 foot bene now has 45hp engine and 200l tank which is probably around a day worth motoring. The fellow with the ovean volt NEEL51 is getting 7 hours of motoring, so if we 2x the density and 2x the capacity we are almost there. Certainly within reason for 2030. For capacity you just need to shave another ton off the neel 51, the neel 51 sport is already 2 tons lighter by going to carbon mast and other doodads.