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Old 06-04-2021, 13:02   #481
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Re: Jimmy Cornell goes Electric, with a Cat

I've enjoyed the whole experiment. I feel it has been a measurable test for the realities of where we are at with renewable electric power and boating today. It is something more concrete than the sales talk we hear and it should be referenced by anyone considering if it is right for them or not.

This has been very public and maybe not quite transparent but at least translucent series of events.

It is a shame it looks like it's over, I would like to see it developed further as an ongoing R&D project with more honesty than we have been used to. It is worthwhile.

As a side note, how is it possible that the boat can motor at over 4kn using 1kw of power ? They must of had some breeze. I believe they had 2 X 15kw motors and maximum speed using both motors was 6.5kn.

1kw = 4.2kn / 30kw = 6.5kn ?

If 30kw = 6.5kn then you would expect 1kw would = around 1kn
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Old 06-04-2021, 13:25   #482
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Re: Jimmy Cornell goes Electric, with a Cat

Quote:
Originally Posted by Dave_S View Post
I've enjoyed the whole experiment. I feel it has been a measurable test for the realities of where we are at with renewable electric power and boating today. It is something more concrete than the sales talk we hear and it should be referenced by anyone considering if it is right for them or not.

This has been very public and maybe not quite transparent but at least translucent series of events.

It is a shame it looks like it's over, I would like to see it developed further as an ongoing R&D project with more honesty than we have been used to. It is worthwhile.

As a side note, how is it possible that the boat can motor at over 4kn using 1kw of power ? They must of had some breeze. I believe they had 2 X 15kw motors and maximum speed using both motors was 6.5kn.

1kw = 4.2kn / 30kw = 6.5kn ?

If 30kw = 6.5kn then you would expect 1kw would = around 1kn
I echo your and sadness at the abrupt end, particularly since it seems there might've been some simple mitigations that would've allowed them to proceed. Also, in the interest of science, it would've been nice to see them complete the entire trip even if the carried a portable generator for emergencies to just rack up some more data with their state-of-the-art setup.

As for the speeds and power, I think this is one area where electric motors can really shine. Our dual 7.1kW PODs can move our 38ft. FP Athena cruising catamaran at around 3.5knots with just 1kW of total power (500W each), so I don't find it hard to believe that their more efficient hulls, even with the added weight, could move a bit more quickly with the same power. I'd be surprised if their top speed was just 6.5knots with that much motor; we've hit close to 7 knots consuming just 9kW of power (the highest we've been able to go with current props) and again their higher hull speed should allow for more, no? Perhaps there's more loss through the saildrive leg than I'd imagined; our PODs are direct drive; no gearing since they're in the water stream 14" below the surface.

I also think a boat that size could've easily accommodated more batteries while still being lighter than twin diesels with fuel tank (obviously not comparable range, however). Our boat lost around 1100 lbs of weight when we removed the twin Yanmar 2GM20fs coupled to SD20 sail drives and the ~400lb fuel tank. We've only added back 2x electric PODs (55lbs each), some electronics/wire (<100lbs) and 4x Tesla battery modules (55lbs each) for around 430 lbs and our sterns are still sitting a few inches higher than the bows with >600lbs to go before we're back to normal. We're doubling our battery capacity as a result and will still be a ~250 lbs light. Their boat easily has twice the capacity of ours and also no diesels/tanks, so it should have well over 100Whr of battery which would've helped them a bit.

Lastly, the induction stove and microwave both use pretty trivial amounts of electricity given how intermittent their use is. You crank it at 1300-1500W for 1-3min before everything is hot and then simmer at 300-500w for usually less than an hour for most meals and that's not even 1kWh, I don't think.
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Old 06-04-2021, 13:57   #483
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Re: Jimmy Cornell goes Electric, with a Cat

I think their problem was, that they did not calculate the comsumption correctly.
And I am thinking more of the fridges, then the cooking.
We'll see how it turns out, if they are giving it an other try or if sells the boat.
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Old 06-04-2021, 13:58   #484
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Re: Jimmy Cornell goes Electric, with a Cat

If you want to save CO2, just use the sails and don't use the engines, no recuperation means sail faster and longer by removing the brake. I mean folding props deliver 0.5...1kn more speed in contrast to fixed props. No regen, and you are better off. Use the Diesel when you really need it only.
Circumnavigating is a marathon, not a sprint. Engines are useless in such large legs. You use the trades - recuperation is a bad thing there, like a drogue or sea anchor. .

We have a motoring range of 1000nm with diesel, a range of 60nm is not addequate for ocean crossings, consider dismasting. No recuperation and a disabled vessel adrift for months.

Solar of 1.5kW gives you 6kWh or a motoring range per day of 16nm (you still need to make water, run fridges and cook food) ?
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Old 06-04-2021, 14:48   #485
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Re: Jimmy Cornell goes Electric, with a Cat

There will be many failures over the long haul but kudos to those who are pushing the technology farther along. I believe that the alarming weather trends we are seeing lately are signs that catastrophic change is well on its way. I have hope that a switch to renewable energy can at least slow it down.

The Wright Brothers didn't just get their plane off the ground and suddenly we had jumbo jets. There were a lot of incremental innovations that got us there, and thanks is due to the contributors who will almost certainly improve efficiency of solar cells, batteries etc. over the coming decades.
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Old 06-04-2021, 14:51   #486
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Re: Jimmy Cornell goes Electric, with a Cat

how are you (yes you) going to get China, India and Indonesia to stop their fossil fuel CO2 burning since they contribute over 80% of the worlds total CO???
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Old 06-04-2021, 14:54   #487
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Re: Jimmy Cornell goes Electric, with a Cat

Quote:
Originally Posted by Dave_S View Post
I've enjoyed the whole experiment. I feel it has been a measurable test for the realities of where we are at with renewable electric power and boating today. It is something more concrete than the sales talk we hear and it should be referenced by anyone considering if it is right for them or not.

This has been very public and maybe not quite transparent but at least translucent series of events.

It is a shame it looks like it's over, I would like to see it developed further as an ongoing R&D project with more honesty than we have been used to. It is worthwhile.

As a side note, how is it possible that the boat can motor at over 4kn using 1kw of power ? They must of had some breeze. I believe they had 2 X 15kw motors and maximum speed using both motors was 6.5kn.

1kw = 4.2kn / 30kw = 6.5kn ?

If 30kw = 6.5kn then you would expect 1kw would = around 1kn
Simple-they lied.
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Old 06-04-2021, 14:56   #488
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Re: Jimmy Cornell goes Electric, with a Cat

First we deal with our own problems then we help others deal with theirs.

Others doing something morally wrong does not excuse us for doing the same thing.
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Old 06-04-2021, 15:02   #489
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Re: Jimmy Cornell goes Electric, with a Cat

Also you are over-stating their contribution.
Last China & India & Indonesia together accounted for 37%.

https://www.ucsusa.org/resources/eac...-co2-emissions
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Old 06-04-2021, 15:03   #490
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by geoleo View Post
Simple-they lied.
No, they just told alternative facts, they waited for a favorable stream pushing the vessel, probably light winds too, no swell...
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Old 06-04-2021, 15:04   #491
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Re: Jimmy Cornell goes Electric, with a Cat

Quote:
Originally Posted by Adelie View Post
Also you are over-stating their contribution.
Last China & India & Indonesia together accounted for 37%.

https://www.ucsusa.org/resources/eac...-co2-emissions
You look at emissions per person, not at the total amount. As they are many and still rural underdeveloped, they may look good, but the total mass of co2 emissions is huge.
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Old 06-04-2021, 15:15   #492
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Re: Jimmy Cornell goes Electric, with a Cat

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Also you are over-stating their contribution.
Last China & India & Indonesia together accounted for 37%.

https://www.ucsusa.org/resources/eac...-co2-emissions
Yes I guessed -but no one really knows the actual numbers and politicians lie routinely. I also guess that these countries want a better life and the way they see to get it is thru cars and electricity and all that brings burning more fossil fuel ,not less. I also guess that they are avid members of the Paris Climate Accords. lol
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Old 06-04-2021, 15:54   #493
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by geoleo View Post
how are you (yes you) going to get China, India and Indonesia to stop their fossil fuel CO2 burning since they contribute over 80% of the worlds total CO???


Bitching and whining about what others do to justify ones actions is 5th grade childish, but that appears to be the norm these days.
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Old 06-04-2021, 16:18   #494
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Re: Jimmy Cornell goes Electric, with a Cat

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Bitching and whining about what others do to justify ones actions is 5th grade childish, but that appears to be the norm these days.
Duh -its called "finger pointing".
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Old 06-04-2021, 16:20   #495
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Re: Jimmy Cornell goes Electric, with a Cat

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Bitching and whining about what others do to justify ones actions is 5th grade childish, but that appears to be the norm these days.
Biden is going to send John Kerry on Air Force One to go over there and extinguish their fires. He will take Hunter Biden with him to advise on bank of China personal loans. Then they will write a book and promote it on CNN.
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