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Old 30-10-2021, 10:23   #706
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by Flobble View Post
Also true. Especially if the attitude changes from 'burn diesel to solve problems' to 'sail according to the forecast'.
This is an interesting reality. Electric cars have taken off, because the current state is that you can use the electric car much like a gasoline car. You drive it where you want, when you want, at the speed you want. The primary limitation is that you have 200 mile range, rather than the 300-400 miles that you had -- and that's a pretty small limitation. And when you compare the total carbon impact of an electric car that drives 10,000 miles a year at the speed limit to a gas car doing the same, it compares favorably (although not all analyses have the same conclusion...).



The reality now, and for the foreseable future, is that boaters will need to change the way most users use them. Good or bad, we like to have 400 mile+ range, at 6-7 knots, without a charging station. We like to be able to motor at 6-7 knots a couple hours a day for weeks, without finding a fuel dock.


So, the often suggested "solution" is to change our expectation. To sail the boat according to the wind. To accept a 10 hour sail at 2 knots, versus a 3 hour motor at 7 knots. That's a hard sell to begin with (cause the reason we do what we do is we want to!). But it's worse -- because now you are comparing the carbon footprint (and $$ footprint!) of a boat that burns 100, 200, even 300 gallons of fuel a year (yes, we had a bad summer, burning over 300 gallons...) to an electric friendly sailor that only motors small distances at low speeds. The carbon savings of an electric boat (including all those supply chain costs) should NOT be to me, burning 300 gallons a year in a 55HP diesel at hull speed, but a "sailor's sailor" with a 7HP diesel that runs at 3-4 knots for 10-20 hours a year, burning less than 10 gallons a year. And I would suggest that an all-electric boat would not compare well to a diesel boat that burns 100 gallons a decade.
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Old 31-10-2021, 01:58   #707
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by sailingharry View Post
This is an interesting reality. Electric cars have taken off, because the current state is that you can use the electric car much like a gasoline car. You drive it where you want, when you want, at the speed you want. The primary limitation is that you have 200 mile range, rather than the 300-400 miles that you had -- and that's a pretty small limitation. And when you compare the total carbon impact of an electric car that drives 10,000 miles a year at the speed limit to a gas car doing the same, it compares favorably (although not all analyses have the same conclusion...).
Agreed. At least for the mass market, and especially when technology changes faster than people's habits/expectations.


Quote:
So, the often suggested "solution" is to change our expectation. To sail the boat according to the wind. To accept a 10 hour sail at 2 knots, versus a 3 hour motor at 7 knots.
That might be one choice, but there are others. Stay where I am and wait for wind. Or accept that my serial hybrid approach means I don't motor at hull speed. So maybe it's 4 hours at 5 knots, because I've only got half as much power available. But I'm using half as much fuel to get there.

Quote:
And I would suggest that an all-electric boat would not compare well to a diesel boat that burns 100 gallons a decade.
I think that's fair. But I still think it might be worthwhile for the reduction in diesel usage, the benefits of silent running most of the time, the smaller number of fuels on board, reduced maintenance, lower weight, etc, etc.
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Old 31-10-2021, 02:04   #708
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Re: Jimmy Cornell goes Electric, with a Cat

[QUOTE=Adelie;3511366]Best overall fuel efficiency is a parallel hybrid.

A series hybrid will only gain an efficiency advantage over ICE or parallel by going slower.[\QUOTE]
Agreed. That's the compromise for the benefit of fewer ICEs & fuels on board.

Quote:
If you have a diesel anything aboard you are still probably a 2 fuel boat as you likely are carrying gas for an outboard.
My proposal is an electric outboard, charged off the same system as everything else in the boat. So no gasoline.

I'd love to get rid of every fossil fuel, but I just don't think it's practical yet. Hence the genset/serial hybrid approach which brings most of the benefits.
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Old 31-10-2021, 02:40   #709
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Re: Jimmy Cornell goes Electric, with a Cat

I think there will be an uptake on light and fast cats first.

My cat can motor nicely at almost 5 knots with very little power needed in a calm - half throttle on a 9.9 outboard. Going 7 is our typical cruising speed with our larger 25, just before we start making big waves. We usually sail at 7-8 so that is what we plan on but we could change a bit.

If the power required is 4KW for motoring in a calm, then there is a good chance in a few years I could put 2KW of panels on the boat if needed. With 2000AH of lithiums we could motor at 4KW and 5 knots, fully depleting the batteries after 6 hours, so we could motor 30 miles, but we wouldn't do 100 % capacity.

In the day we could have the 2KW coming in, so we could almost double our range to 50 miles or so.

I don't think it is incredibly hard for me to get 2000 watts of solar on my cat, or a 2000AH battery system. Then I would never have to refuel my boat unless I needed to motor more than say 25 miles on a cloudy day. It might be that in the end, never having to fuel up becomes a real plus.

But for a heavy mono, the maths does not add up. They require much more grunt to push and have much less panel room.

cheers

Phil
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Old 31-10-2021, 03:21   #710
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by catsketcher View Post
I think there will be an uptake on light and fast cats first. cheers

Phil

The problem is that light fast production cats don't really exist and they are getting heavier year on year.



A stock (light fast) Outremer 55 is fitted as standard with 2 x 60hp diesels. A Lagoon 450 with 2 x 55hp


Compare a 1990's Lagoon 47 to a 2020's Outremer 45 and they have virtually the same specifications. 47/48ft circa 10 tonnes. 30 years of materials tech and no significant difference. A case of buyers demanding more stuff or more luxury.


If you just removed all the unnecessary wood trim and teak decks the boating industry would drastically reduce it's carbon footprint, but it would seem that is not what buyers really want.
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Old 31-10-2021, 03:30   #711
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by catsketcher View Post
I think there will be an uptake on light and fast cats first.

My cat can motor nicely at almost 5 knots with very little power needed in a calm - half throttle on a 9.9 outboard. Going 7 is our typical cruising speed with our larger 25, just before we start making big waves. We usually sail at 7-8 so that is what we plan on but we could change a bit.

If the power required is 4KW for motoring in a calm, then there is a good chance in a few years I could put 2KW of panels on the boat if needed. With 2000AH of lithiums we could motor at 4KW and 5 knots, fully depleting the batteries after 6 hours, so we could motor 30 miles, but we wouldn't do 100 % capacity.

In the day we could have the 2KW coming in, so we could almost double our range to 50 miles or so.

I don't think it is incredibly hard for me to get 2000 watts of solar on my cat, or a 2000AH battery system. Then I would never have to refuel my boat unless I needed to motor more than say 25 miles on a cloudy day. It might be that in the end, never having to fuel up becomes a real plus.

But for a heavy mono, the maths does not add up. They require much more grunt to push and have much less panel room.

cheers

Phil
Just playing devils advocate here, the electric motors, along with the big battery bank and the big solar array is going to make your boat quite a bit heavier...
Maybe a worthy trade off though...
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Old 31-10-2021, 12:32   #712
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by Tupaia View Post
The problem is that light fast production cats don't really exist and they are getting heavier year on year.



A stock (light fast) Outremer 55 is fitted as standard with 2 x 60hp diesels. A Lagoon 450 with 2 x 55hp


Compare a 1990's Lagoon 47 to a 2020's Outremer 45 and they have virtually the same specifications. 47/48ft circa 10 tonnes. 30 years of materials tech and no significant difference. A case of buyers demanding more stuff or more luxury.


If you just removed all the unnecessary wood trim and teak decks the boating industry would drastically reduce it's carbon footprint, but it would seem that is not what buyers really want.
Good point.
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Old 31-10-2021, 15:30   #713
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Re: Jimmy Cornell goes Electric, with a Cat

Quote:
Originally Posted by Tupaia View Post
The problem is that light fast production cats don't really exist and they are getting heavier year on year.



A stock (light fast) Outremer 55 is fitted as standard with 2 x 60hp diesels. A Lagoon 450 with 2 x 55hp


Compare a 1990's Lagoon 47 to a 2020's Outremer 45 and they have virtually the same specifications. 47/48ft circa 10 tonnes. 30 years of materials tech and no significant difference. A case of buyers demanding more stuff or more luxury.


If you just removed all the unnecessary wood trim and teak decks the boating industry would drastically reduce it's carbon footprint, but it would seem that is not what buyers really want.

The new Outremer 55 can no longer be considered light, except by comparison to one of the big 3. Comparing our first generation 55L to the new 55:

Displacement: 7.5/11.5 vs 13.9/18.5 (+85%/+61%)

Upwind sail area: 115 vs 172 (+49%)

Standard engine: 35hp vs 60hp (+71%)

It’s a bloated beast that is an insult to Danson’s memory (they should have called it a 54 or 56, not 55), but obviously what buyers now want in terms of accommodations and fittings. Oh well.

Not sure what wood or teak have to do with it - it’s all veneers on foam core, or rubber (in place of teak). Solid wood is too heavy for no purpose in the interior and as for teak outside, nobody wants to maintain real teak anymore (did they ever?).
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Old 31-10-2021, 15:37   #714
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Re: Jimmy Cornell goes Electric, with a Cat

Quote:
Originally Posted by Flobble View Post
Quote:
Originally Posted by Adelie View Post
Best overall fuel efficiency is a parallel hybrid.

A series hybrid will only gain an efficiency advantage over ICE or parallel by going slower.
Agreed. That's the compromise for the benefit of fewer ICEs & fuels on board.


My proposal is an electric outboard, charged off the same system as everything else in the boat. So no gasoline.

I'd love to get rid of every fossil fuel, but I just don't think it's practical yet. Hence the genset/serial hybrid approach which brings most of the benefits.
Dinghies have the same issues as motherships when converting to electric: range and speed. If you use enough power to get on a plane, your range will be drastically diminished.

Understand that I am seriously pro-EP, but I want folks to understand the limitations when they get into it.
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Old 31-10-2021, 18:36   #715
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by JustMurph View Post
Just playing devils advocate here, the electric motors, along with the big battery bank and the big solar array is going to make your boat quite a bit heavier...

Maybe a worthy trade off though...


For the boat I want replacing the Atomic-4 with 200Ahr @48v, plus motor and cabling was about even.
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Old 01-11-2021, 02:53   #716
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Re: Jimmy Cornell goes Electric, with a Cat

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Originally Posted by sailingharry View Post

The reality now, and for the foreseable future, is that boaters will need to change the way most users use them. Good or bad, we like to have 400 mile+ range, at 6-7 knots, without a charging station. We like to be able to motor at 6-7 knots a couple hours a day for weeks, without finding a fuel dock.

The carbon savings of an electric boat (including all those supply chain costs) should NOT be to me, burning 300 gallons a year in a 55HP diesel at hull speed, but a "sailor's sailor" with a 7HP diesel that runs at 3-4 knots for 10-20 hours a year, burning less than 10 gallons a year. And I would suggest that an all-electric boat would not compare well to a diesel boat that burns 100 gallons a decade.
I fully agree that any comparison has to be fair, so expected distance traveled by motoring or motor-sailing has to be the same diesel/gas vs. electric.
But I suspect that your assumption that a sailboat with minimal motoring is better off with diesel than electric to be wrong. For minimal use an electric outboard/inboard with a small battery is sufficient, low maintenance and cheap and certainly greener than a (new) diesel inboard or gas outboard. Whether a conversion makes sense is another question entirely, especially as the replaced engine usually has a second life.
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Old 01-11-2021, 05:39   #717
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Re: Jimmy Cornell goes Electric, with a Cat

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I fully agree that any comparison has to be fair, so expected distance traveled by motoring or motor-sailing has to be the same diesel/gas vs. electric.
But I suspect that your assumption that a sailboat with minimal motoring is better off with diesel than electric to be wrong. For minimal use an electric outboard/inboard with a small battery is sufficient, low maintenance and cheap and certainly greener than a (new) diesel inboard or gas outboard. Whether a conversion makes sense is another question entirely, especially as the replaced engine usually has a second life.
I can't agree on either point.


* The EP supporters suggest that an appropriate replacement for the 55 HP diesel (with 94 gal fuel!) on my boat is a 20HP equivalent, with enough battery to motor at 4 knots for 30 miles (or 6 knots for 5 or 10 miles). Even the most ardent supporter wouldn't recommend anything in the 3-5hp rating for a 22,000 lb 43 foot boat! However, I do see HUGE benefit in that thought for smaller boats. There is a Harbor 20 in our race fleet, at the end of the race he flips out this custom Torqueedo on an arm in his lazarette, and motors home at 4 knots -- WAY COOL!


* As far as conversions, I'm not sure there is much resale value. Most conversions are instigated by a belief that their engine is about dead. Few (but some) take out an engine with significant resale value. But more important, it's talking about hobbyist economies -- like using discarded Tesla batteries, or collecting vegetable oil from McDonald's for bio-diesel, it's not an equation that translates to large scale.
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Old 01-11-2021, 13:01   #718
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Re: Jimmy Cornell goes Electric, with a Cat

Life's too short for motoring at 4 knots. Just sayin'.
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Old 01-11-2021, 14:28   #719
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Re: Jimmy Cornell goes Electric, with a Cat

This discussion is ridiculous, we are talking about replacing a tiny toy 40..50hp efficient diesel engine, that limps us home in unfavorable weather or is used for docking - by an expensive electric drive or hybrid. But forgetting the small tripper boats with 3 to 4 x 250hp gas outboard engines, or the real deal power boats with several 1000hp, that go to the fuel dock after a joy ride for a day and refill 4000$ worth of diesel. Who cares if a sailing cat burns 200 or 300l per year really, when the charterers burn it on a daily basis?
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Old 01-11-2021, 14:42   #720
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Re: Jimmy Cornell goes Electric, with a Cat

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This discussion is ridiculous, we are talking about replacing a tiny toy 40..50hp efficient diesel engine, that limps us home in unfavorable weather or is used for docking - by an expensive electric drive or hybrid. But forgetting the small tripper boats with 3 to 4 x 250hp gas outboard engines, or the real deal power boats with several 1000hp, that go to the fuel dock after a joy ride for a day and refill 4000$ worth of diesel. Who cares if a sailing cat burns 200 or 300l per year really, when the charterers burn it on a daily basis?
Even though I'm an electric enthusiast, from an overall environmental point of view, as well with consideration of today's costs and levels of technology, it's hard to argue with that.

Sailing boats don't generally burn much diesel in the first place. An an optimised sailing boat, both in terms of sailing efficiency as well as energy production, burns even less.

But if building a new boat for the long term or doing a major refit that requires engine replacement the merits may change somewhat.

And in the future the entire scenario should be different too.

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