Jimmy Cornell goes Electric, with a Cat

[danstanford]

Originally Posted by CatNewBee

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?

Certainly it is hard to make a valid economic argument to replace your diesel with an electric engine, however the world is full of such tough decisions and I cannot for the life of me understand the vitriolic way we criticize people trying to do the 'right' thing!

Your opinion is valid for you but is not helpful in pursuit of a better truth for some others. If we made decisions on an economic basis entirely we would not transform the world in many ways. Finally, just watch our governments make the economic equations look different for all of us through tariffs and taxes to encourage us to make different decisions because we won't do enough without this encouragement. Make no mistake, you will ultimately help pay for these changes whether you agree with them or not.

[Simon.Sails]

Originally Posted by Adelie

You indicated comparison had to be fair and they had to have similar ranges.

I'm not sure if you're serious. I suggested they had to be compared at similar ranges (and speed) to give a clear understanding of their relative strengths. Boats that sail well, motor occasionally at lower speeds might find that EE suits them better, whereas boats that don't sail/point well, want to motor at higher speeds and for longer durations might find that diesel or parallel hybrid is their only viable option.

[Adelie]

Originally Posted by Simon.Sails

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.
.....

Originally Posted by Simon.Sails

I'm not sure if you're serious. I suggested they had to be compared at similar ranges (and speed) to give a clear understanding of their relative strengths. Boats that sail well, motor occasionally at lower speeds might find that EE suits them better, whereas boats that don't sail/point well, want to motor at higher speeds and for longer durations might find that diesel or parallel hybrid is their only viable option.

I was serious. Perhaps you worded it poorly in your original post which I included at top. If so never mind.

[BigBeakie]

Originally Posted by Adelie

It’s not fair and never will be. Electric will never have the same performance as a diesel.
Electric can’t match the significant range at speed that diesel can provide.
Diesel can’t match electric’s unlimited range at slow speed without refueling.

Apple-oranges comparison, always will be.
Choosing EP is a values decision.

I'm not sure you can be as absolute as that, " Electric will never have the same performance as a diesel." Never is a very, very long time.

The more I learn about what's happening in clean hydrogen technology development and fuel cell improvement to replace batteries, the more hopefull it looks.

[goboatingnow]

Originally Posted by Adelie

It’s not fair and never will be. Electric will never have the same performance as a diesel.
Electric can’t match the significant range at speed that diesel can provide.
Diesel can’t match electric’s unlimited range at slow speed without refueling.

Apple-oranges comparison, always will be.
Choosing EP is a values decision.

You need to distinguish between engine and the energy store

Electric motors are superior in every aspect to a Diesel engine , they are more powerful weight by weight , more efficient , quieter, more responsive and better torque characteristics.

The magic is the energy store that is diesel fuel, which is approx 10kWh/L , the best Litium metal batteries today are around 0.9 kWh/L , but the equivalent energy efficiency comparison brings that to about 2kWh/L, still 5 times less efficient then carrying diesel, but technology moves on and solid state Lithium technologies ( with no cobalt requirement ) is on the horizon with upwards of 6 kW/L equivalent energy density. Couple this to the fact that you can’t make diesel at sea , but you can make electricity and you can clearly see that the energy density issue is on a path to be overcome.

Once you solve the density issue to within the consumer demands , no one is ever going to use a Diesel engine outside a museum, in the same way steam is not used to provide mainstream motive power since the 60s . Not to far into the future kids will marvel in wonderment that you once poured this smelly messy explosive liquid into a tank and carried it around with you.

Suddenly “never” isn’t so far away.

[goboatingnow]

Originally Posted by BigBeakie

I'm not sure you can be as absolute as that, " Electric will never have the same performance as a diesel." Never is a very, very long time.

The more I learn about what's happening in clean hydrogen technology development and fuel cell improvement to replace batteries, the more hopefull it looks.

Hydrogen powered transport is going nowhere. It’s the Hindenburg of energy storage, the future is electric and electric storage

[Adelie]

Originally Posted by BigBeakie

I'm not sure you can be as absolute as that, " Electric will never have the same performance as a diesel." Never is a very, very long time.

The more I learn about what's happening in clean hydrogen technology development and fuel cell improvement to replace batteries, the more hopefull it looks.

I am arrogant enough about this to opine that it will not occur within the lifetime of anybody now alive.

Hydrogen has several problems:
Energy density and specific energy are only modestly better than LiFePo when the weight of storage containers are included in the calculations, nevermind being anywhere close to diesel.

Here's a previous post I did on this: https://www.cruisersforum.com/forums...ml#post3448570

Storage involves compressing it or liquifying it. Even in the best Dewar tanks let some heat in so the liquid H2 gassifies and has to be used or vented.
Compressed H2 will last better but it still migrates thru any tank material and you slowly loss the H2. For short term storage this is fine. Long term you lose the fuel whether you use it or not. Somewhere in the middle term is where it become uneconomical

For consumer use, my money is on synthetic hydrocarbons:
Petrol/gas
Diesel
Butanol
Methanol
They all have pretty good energy density and specific energy and can be stored at room temp in cheap tanks. Whether they will be run thru ICE or fuel cells remains to be seen.
They will be expensive enough that boats will be optimized for low drag, even the power vessels.

What happens in the commercial sector is less obvious, with trained personnel, use of things like Ammonia for ships and liquid H2 for aircraft are possible, it's just not currently clear how the economies of each sure will shake out.

[Adelie]

Originally Posted by goboatingnow

Hydrogen powered transport is going nowhere. It’s the Hindenburg of energy storage, the future is electric and electric storage

I think the future is going to be very fragmented, with different technologies being predominant in different niches. Overall electricity will dominate.

[Adelie]

Originally Posted by goboatingnow

You need to distinguish between engine and the energy store

Electric motors are superior in every aspect to a Diesel engine , they are more powerful weight by weight , more efficient , quieter, more responsive and better torque characteristics.

The magic is the energy store that is diesel fuel, which is approx 10kWh/L , the best Litium metal batteries today are around 0.9 kWh/L , but the equivalent energy efficiency comparison brings that to about 2kWh/L, still 5 times less efficient then carrying diesel, but technology moves on and solid state Lithium technologies ( with no cobalt requirement ) is on the horizon with upwards of 6 kW/L equivalent energy density. Couple this to the fact that you can’t make diesel at sea , but you can make electricity and you can clearly see that the energy density issue is on a path to be overcome.

Once you solve the density issue to within the consumer demands , no one is ever going to use a Diesel engine outside a museum, in the same way steam is not used to provide mainstream motive power since the 60s . Not to far into the future kids will marvel in wonderment that you once poured this smelly messy explosive liquid into a tank and carried it around with you.

Suddenly “never” isn’t so far away.

Diesel is 10.3kW/l. Of course after running thru an ICE the energy delivered to a prop is about 1/3 of that per liter.

The cutting edge of Li-ion batteries is about 0.6kWh/l but that chemistry will never become commercially viable at scale due to the relative rarity of some of the constituents. Commercially available cells are running about 0.2kWh/l. Solid State Lithium is sitting at about 0.4kWh/l and will likely be that good or better when it becomes commercially viable at our level, say in 10-15yr.

But energy density isn't that important compared to specific energy. Diesel is about 12.6kWh/kg, vs LiFePo at about 0.15. Solid State look to double that in about 10-15yr. Even if batteries get to 1kWh/kg (in 100yr), they will still be less than 1/3 that of diesel even accounting for efficiency loses in an ICE.

To me the future is likely to hybrid propulsion where synthetic fuels are used and they will rather expensive so people will maximize alternative charging means, solar, wind, regen.

[BigBeakie]

This needs it's own thread, but for starters the energy density of diesel is as Adelie said, 10.3kW/kg, while hydrogen is more than triple that at 33.4kW/kg. So much for the energy density superiority of diesel.

Of course the future is electric, electric motors, what do you think the fuel cell produces? The fuel cell membrane technology currently in use by FCEV produces up to 250kW per bank, and there are test buses, cars and commercial trucks running on H2 right now. And the trucks can even drive up hills, how about that!

The push, as I understand it, is to accomplish 2 main things, 1. commercialise fuel cell tech in the transport industry and 2. produce clean H2 at $2/kg or less, including from scalable hydrolysers here in Oz. There is hundreds of millions of bucks and human smarts focused on those issues right now. It is not a futuristic pipe dream.

[downunder]

Are the fuel cells under Pressure??

Not sure I would be wanting to drive a vehicle running on high pressure hydrogen

[kiwin]

Hydrogen as energy storage is always going to be massively innefficient compared with batteries. That alone will limit it's use to applications where battery electric will not work. A cruising yacht may be one of those applications. A passenger car will never be.

[BigBeakie]

Originally Posted by downunder

Are the fuel cells under Pressure??

Not sure I would be wanting to drive a vehicle running on high pressure hydrogen

But what about LPG? You won't get in a taxi running on LPG?

[BigBeakie]

Originally Posted by kiwin

Hydrogen as energy storage is always going to be massively innefficient compared with batteries. That alone will limit it's use to applications where battery electric will not work. A cruising yacht may be one of those applications. A passenger car will never be.

Inefficient in what sense? Hydrogen would solve the range issue at higher power levels, compared to battery.

[double u]

isn't H² the stuff where the tank has 600bar??? (there is a thread on CF concerned with the dangers of Propane on board...)
2 points:
1. we were "out there doing it" for quite some time & distance - & where were all you electric-drive-proponents? We met ONE electrically drive boat (in the 90iea, lead-acid batts, with runtime & performance that went with that.
2.I would never say "never"! People way smarter than any of us (Lord Kelvin, Edison,...) pronounced "flight heavier than air" as late as 1985 impossible, & "personal communicators" were the stuff of scifi not so long ago. "not in our lifetime" is along these lines too, nobody can predict the inventions of 2026.