Jimmy Cornell goes Electric, with a Cat

[Adelie]

Originally Posted by Yihang

We are talking about uma’s recent sail on a salona 460 with twin OV. Not their old boat.

That’s what the video is about.

Wing sail brought up Uma in post 437 and I was responding to him.

[Adelie]

Originally Posted by jbinbi

Sorry to go a bit OT here, but food science people shudder at this. Bacteria grow at > 40 F. Chicken at 80 F is not recommended. It might save you some Watts, but potentially you will lose the savings in toilet paper used....[emoji22]

I understand that bacteria grow at >40F. And a lot of food storage rules are geared to keeping the food cold enough so that most bacteria can’t grow for long periods or keeping the warm periods short enough that the colonies don’t have time to grow significantly.

Related but not exactly the same here’s a study of different methods of thawing. USDA rules allow thawing from frozen in ambient temperature rather than in a refrigerator for meat processing plants. Ambient temp thawing at 70F may be safer than fridge thawing.
https://animalscience.psu.edu/outrea...mbienttemp.pdf

I spent part of my childhood living in a developing country. We had a fridge but meat was often obtained from a market and in many of the stalls the meat had never been refrigerated. The trick was to cook it or refrigerate it relatively soon. If you obtained the meat cold then you will have a period where the it can reside at warmer temps before significant bacterial growth can occur.

The point of FDA rules for food service workers is clear bright easy to understand guidance with a very large factor of safety for workers who may not care that much.

[Seafarer7]

Energy vs Power: energy is key!
I would argue that hydro-generators count and make all the difference especially on ocean crossings. Don’t have an all-electric cat, but I see some similarities with my 39-foot monohull, with its twin diesel engines, each having a DIY hydro-generator attached to the prop shaft. In addition to the two hydro-generators there’s 1,050 watts of solar panels, all feeding the single 1,250 AHr bank of AGM batteries.

Have done extensive testing and data-collection in multiple modes, including a couple ocean crossings (California to Hawaii and back). And while the observed maximum power output of both hydro generators combined is low compared to solar (ie ~200w), the total daily ENERGY produced by the hydro generators significantly exceeded the energy contribution from solar, and made it possible to maintain balance and in some cases have excess energy, during long voyages.

On the Pacific crossings energy consumption was significant, with the all-electric galley (induction cooker, rice cooker, electric kettle, microwave), refrigerator, washer dryer, nav equipment including autopilot operating 24x7, MFD, stereo, DC water maker, computers and a few other 120v appliances operated via a 3kw pure sine inverter. Granted typical electric consumers were optimized (eg all-LED lighting) and there was propane galley backup (available but rarely used), still I estimate using 340 - 400 Ah of energy daily.

On a good day, the solar panels could hit 60 - 70 amps easily, close to 800 watts of power. However over a 24 hour period the total energy harvested from the solar panels alone rarely exceeded 200 Ah. The twin hydro-generators on the other hand rarely exceeded 15amps combined, or 200watts of power. And yet at the end of each 24 hour period the total energy from the hydro-generators typically exceeded 200 Ah, more than the daily solar energy harvest. So even though they were much lower power than solar, because they ran nonstop, night and day, those twin hydro generators contributed much more energy (sometimes surplus) and made it possible to sail for days on end without the need to fire up a Diesel engine.

[aqfishing]

Heres an interesting concept I have not seen before. I would think it would not be too hard to make this system regen as well.

https://youtu.be/Te_xejpriFM

[Matt Johnson]

Vetus offers a 10kw rim driven pod. But with so much drag from the housing, I cant imagine installing that on a sailboat.

Matt

Originally Posted by aqfishing

Heres an interesting concept I have not seen before. I would think it would not be too hard to make this system regen as well.

https://youtu.be/Te_xejpriFM

[barrymac]

Originally Posted by aqfishing

Heres an interesting concept I have not seen before. I would think it would not be too hard to make this system regen as well.

https://youtu.be/Te_xejpriFM

this is another turbine style drive that is claiming great efficiency. I asked them, and their solution doesn't do regen though.

https://www.sealence.it/deepspeed/

[Adelie]

Originally Posted by barrymac

this is another turbine style drive that is claiming great efficiency. I asked them, and their solution doesn't do regen though.

https://www.sealence.it/deepspeed/

The duct looks like an affectation to make it look sexy for marketing purposes.

[Peter-Jan]

Aventura Zero is now for sale by Outremer brokerage: https://catamaran-outremer.com/occas...hp?val=7799003

Asking price 989K euro ex VAT, price "new from yard" is quoted as 1.1 million euro ex VAT.

Cornell likely got a discount and some freebies on this boat so I am sure there is room to negotiate on this price.

[CatNewBee]

Originally Posted by Peter-Jan

Aventura Zero is now for sale by Outremer brokerage: https://catamaran-outremer.com/occas...hp?val=7799003

Asking price 989K euro ex VAT, price "new from yard" is quoted as 1.1 million euro ex VAT.

Cornell likely got a discount and some freebies on this boat so I am sure there is room to negotiate on this price.

I wouldn't consider it even for half the price without proper diesel engines.

[geoleo]

Originally Posted by longjonsilver

Well said.

do you have any extra?

[geoleo]

The market for guilty virtue signaller s is huge. Al gore set the example by making $98000000 from his movie, then moving to a huge seaside mansion in California and buying 5 huge SUV s and flying everywhere by private jet.

[mglonnro]

Originally Posted by Peter-Jan

Aventura Zero is now for sale by Outremer brokerage: https://catamaran-outremer.com/occas...hp?val=7799003

Asking price 989K euro ex VAT, price "new from yard" is quoted as 1.1 million euro ex VAT.

Cornell likely got a discount and some freebies on this boat so I am sure there is room to negotiate on this price.

Well, this was certainly a colossal #fail in leading the way towards renewable-powered sailing

If they'd take our current boat as a downpayment and an IOU for the rest, I would love to do it better.

[Peter-Jan]

I think adding a generator for ocean crossings and more solar for day to day is quite easy so this boat is certainly not a write off.

However, what discount do 1 year old boats like this normally go for?

Outremer has another 45 for sale for 790K EUR EU VAT included. I wonder how low you can go when dealing with sellers who clearly changed their mind or realize they can not afford the boat.

It seems Outremer is trying for 10% discount for 1 year old but what does the market do on average? At 25% off I feel those things would be great deals, at 10% off why not spend the extra and get things done exactly the way you want.

[mglonnro]

Originally Posted by Peter-Jan

I think adding a generator for ocean crossings and more solar for day to day is quite easy so this boat is certainly not a write off.

However, what discount do 1 year old boats like this normally go for?

Outremer has another 45 for sale for 790K EUR EU VAT included. I wonder how low you can go when dealing with sellers who clearly changed their mind or realize they can not afford the boat.

It seems Outremer is trying for 10% discount for 1 year old but what does the market do on average? At 25% off I feel those things would be great deals, at 10% off why not spend the extra and get things done exactly the way you want.

IMHO, the market on average is certainly just that, some average of some group of boats at some point of time, and as such not very informative when it comes down to the (largely also subjective) value of one specific boat.

I agree with your reasoning, though!

[yvest]

Some updates from Cornell, not very clear ... :
https://cornellsailing.com/fr/2021/0...ra-zero-plans/