Will electric outboards start replacing diesel inboards?

[DeValency]

Originally Posted by valhalla360

The myth of magic electric HP.

For the same performance, you need the same HP at the prop.

You might gain a few percentage points omitting the transmission. If you want to claim you could use a 15hp electric because you can omit the transmission and run at a higher percentage of rated HP, I'll buy that but you aren't going to replace an 18hp diesel motor with a 9hp (or less as you imply) electric and get the same performance.

Gents - it is physics and engineering case:
a) true engines power are measured in KW not HP
b) electric brushless motor is at least 50% more energy efficient than equivalent diesel and almost 80% more efficient than gas.

Now eliminate the gear, warming up etc and do the math.

[ghostlymoron]

For a lot of sailers like me and long distance cruisers, battery power is completely impractical. Unlike e cars which can rely on finding a charger at regular intervals on the road network, boats do not have the same facility. Also a passage can be delayed and extended by adverse weather which would leave you with no power to complete the trip.
It's a non starter for me - I'll stick to sails.

[valhalla360]

Originally Posted by DeValency

Gents - it is physics and engineering case:
a) true engines power are measured in KW not HPNo, either unit of measurement is perfectly valid and it makes no difference to the end result what unit you use. Do you have difficulty with unit conversions?
b) electric brushless motor is at least 50% more energy efficient than equivalent diesel and almost 80% more efficient than gas. If batteries held the same energy density as diesel and putting that energy into the battery was 100% efficient, this would be correct and everyone would almost immediately switch to electric power. But both of those are false.

Now eliminate the gear, warming up etc and do the math.

If you could just run a long extension cord, electric would win out easily...but it would have done so 50-75yrs ago as electric motors aren't much better than back then.

When you do the math diesel wins out. On a 5hr trip, warming up takes just a few minutes at the begining and then assuming the motor has been properly matched, it is running at near peak efficiency.

Also, you need to define motor efficiency. When the whole process is accounted for, you won't see anything close to 50% o 80% improvements over grid supplied power and using solar is only viable if you have negligible motoring requirements.

[OldMan]

Originally Posted by DeValency

Gents - it is physics and engineering case:
a) true engines power are measured in KW not HP
b) electric brushless motor is at least 50% more energy efficient than equivalent diesel and almost 80% more efficient than gas.

Now eliminate the gear, warming up etc and do the math.

a) unit of measure doesn’t matter, pick one
b) where is the electricity to run the brushless motor coming from? If you are burning diesel to make electricity, converting diesel to mechanical, then to electrical, then back to mechanical is far less efficient than diesel directly connected.

Do the math!

[aqua de vida]

Originally Posted by LuvSun

With so many electric cars now, and the world heading toward safe smaller nuclear options, fossil fuels are looking done for, for the most part.

Im wondering how hard for Sail boats retrofitting electric motors will be. I dont think very hard.

The other thing is with Tesla cells replacing fuel tanks and solar, hydro, wind generating electricity and overflow going to the Tesla plant in the boat, we w could see 100% renewable energy on Yachts. Outside the petroleum used to make plastic components and transport everything.

Yay, maybe that massive Ozone hole over NZ you lot have caused will close up, but late for me Ive already had 4 melanomas out. But it is important to not lose our atmosphere or we will end up like Mars. I watch a lot of Planetary Science and Quantum physics videos if you cant tell ;-p

I saw Neil De Grasse Tyson in Auckland NZ, was a little pricey and he didnt cover anything I didnt already know, but none the less it was fun.

.....I've worked with several lithium battery electric propulsion systems on large cruising yachts! Massive expense for what amounted to about thirty minutes of realistic propulsion!.... I cannot understand why you would bother when bio diesel is now commonplace..... Do some careful research for carbon footprint for such a 'low hours' propulsion system and by the time you have your new 'green' propulsion system manufactured and installed you may have burned the equivalent of many thousands of litres of diesel, let alone bio-diesel or other renewable diesel equivalents!

[LuvSun]

Originally Posted by ghostlymoron

For a lot of sailers like me and long distance cruisers, battery power is completely impractical. Unlike e cars which can rely on finding a charger at regular intervals on the road network, boats do not have the same facility. Also a passage can be delayed and extended by adverse weather which would leave you with no power to complete the trip.
It's a non starter for me - I'll stick to sails.

Thats not realistic and nor is what is being proposed by most installations.


The engine is self powered by hydrogen water conversion to electrons. The exact process has been stated by somebody else as I was unsure how this particular hydrogen system works specifically (refer to CJ18s post on the top of the previous page). Excess energy is saved to BMW I lithium cells to be used for all electric function outside sailing, it also takes hydro, solar, wind like any of the small lithium battery packs currently used.

Read through the thread on how the system works.

[LuvSun]

Originally Posted by aqua de vida

.....I've worked with several lithium battery electric propulsion systems on large cruising yachts!

Can you please state which lithium systems were used, how were they charged and what engines were used?

[LuvSun]

Originally Posted by OldMan

a) unit of measure doesn’t matter, pick one
b) where is the electricity to run the brushless motor coming from? If you are burning diesel to make electricity, converting diesel to mechanical, then to electrical, then back to mechanical is far less efficient than diesel directly connected.

Do the math!

Please read the appropriate points in this thread so you actually know where the electricity for the electric engines are coming from, its not diesel.

This is getting tiring explaining the variety of electric systems over and over again for every person who doesnt read the thread.

If you cant be bothered reading it all, just dont post would be easier. Thank you.

[DeValency]

Originally Posted by OldMan

a) unit of measure doesn’t matter, pick one
b) where is the electricity to run the brushless motor coming from? If you are burning diesel to make electricity, converting diesel to mechanical, then to electrical, then back to mechanical is far less efficient than diesel directly connected.

Do the math!

a) I don’t know of batteries capacity measure in HP... just in AH which is directly converted to KW. Then the motor efficiency translates to the propulsion output.

b) I thought we are mainly using sails on our sailboats (but maybe I’m the real word guy here... ) and the use of the engine/motor is to be determined by the common conditions each one expects to have - each has a very specific set of factors determining the:
* personal preferences - I have no interest to argue with anyone.
* cruising (by sails...) area, overall offshore time, season etc.
* sun and wind can generate electric power right away. - It took 2M years for the nature to produce crude oil and some more years for the mankind to refine it to motor fuels.

c) someone compared it to the issue of all electric cars. While we can learn and use a lot of the e-car tech, cars have no sails, no (large enough) solar panels, no wind generators and are usually expected to move faster than a typical cruising speed of 5-8Kts.

I only suggest hybrid propulsion for the time being. I do not suggest anyone to throw a working Diesel engine, buy a new genset and install a new hybrid propulsion to a sailboat. From the first post I had here the idea is that this is the very near future option to consider with the new “tesla like” batteries when prices drops... and for new boats or for those needing repowering.

Hybrid cars are already well proven for over 15 years. While I’m a big fan of turbo charged diesel cars (I’m driving one) the same car with hybrid is by far better, faster, more economical and cost almost the same.

Not interested in arguing with personal preferences.

[SailFastTri]

All this talk of electric propulsion is of dubious value unless it can be sustained by wind and sun and water regeneration. In most cases it can’t, and in the end it will have no significance on a global level. It’s recreational.
Avoiding meat and dairy products is the single biggest way to reduce your environmental impact on the planet, and improve your own health at the same time.
https://www.theguardian.com/environm...mpact-on-earth

https://www.ucsusa.org/our-work/ucs-...e#.XD3ZkxpMGhA

https://nutritionfacts.org

[NPCampbell]

Originally Posted by DeValency

In your case you are right of course.
But again: I’m speaking of 5-7 years from now on the new batteries.
And - a diesel genset is still going to stay for the next years. And a good one can provide enough charge to drive an electric propulsion for 40 hours - it is mostly a matter of the diesel tank that should be smaller than the one you would need for a driving diesel.

Originally Posted by DeValency

In your case you are right of course.
But again: I’m speaking of 5-7 years from now on the new batteries.
And - a diesel genset is still going to stay for the next years. And a good one can provide enough charge to drive an electric propulsion for 40 hours - it is mostly a matter of the diesel tank that should be smaller than the one you would need for a driving diesel.

The 2 major problems are no where near 5-7 years away. The math is very simple:

1) Energy storage density:
Gas/diesel: 45 MJ/Kg
The best lithium battery: <1 MJ/Kg
The best current lab only, metal air, battery: <4 MJ/Kg
Hydrogen: 120 MJ/Kg ... but requires 20 times the volume of gas/diesel @ 3000psi

2) Poor solar efficiency. The best solar cells provide: 18 watts/sq ft. A massive 20x20 ft solar cell assuming perfect light conditions, imaginary wiring and imaginary regulation generates 7200 watts ... which is less than 10 horsepower.

Each 10 shaft HP you desire requires 7.5kW of power. What technology break through in the next 5-7 years will allow you to store or generate that amount of power using anything other than fossil fuels?

[sailorchic34]

Originally Posted by LuvSun

The engine is self powered by hydrogen water conversion to electrons. The exact process has been stated by somebody else as I was unsure how this particular hydrogen system works specifically (refer to CJ18s post on the top of the previous page). Excess energy is saved to BMW I lithium cells to be used for all electric function outside sailing, it also takes hydro, solar, wind like any of the small lithium battery packs currently used.

CJ18's post does not explain how the system works. Yes US subs use electrolysis to produce o2 and h2 (H2 is tossed). But they have a huge reactor to power it as well. It takes a ton of power which they have. That system does not scale down to the 4kw-6kw level well.

Perhaps in 10-20 years when solar panel efficiencys are 50-60 percent and battery power densities go up and battery costs fall we can talk about it more.

Electric motors work fine. The issue is power storage. Using solar and wind to make hydrogen is a non starter at this time. You can store the solar and wind in batteries, but again range on battery's is measured in minutes, not hours in todays world.

The D80 use of regenerative power would produce storeable energy. Though I strongly suspect that amount produced will be far less then their claimed 60kw. This based on the false claims made with their solar capacity.

First a rated 4kw solar system, never puts out 4kw and that output is only when the sun is directly overhead on a clear 20 degree C day. In the real world, their output would be more in the range of 2.6 to 2.8 kw. unless there is shading on part of the panel cells, which causes a drop of up to 80 percent in output.

What makes Diesel work is that fuel storage thingy, you can pack a ton of kw equivalency in a gallon of diesel. It's 39kw worth per gallon. By weight hydrogen has lots more energy. But by volume, not so much as hydrogen is stored as a gas at 101 bar.

[Jim Cate]

Originally Posted by myocean

Don't want to belive?
Here an interesting video, showing even the charging robot
https://youtu.be/dgg_pohK-q8

dunno where you got the "don't want to believe" idea. The language used in the article was in the future tense, and we've been exposed to a lot of vaporware claims in the past.

The video does show it in use, and it is impressive. Charging in 5 or 9 minutes is very likely faster than transferring enough diesel to make the same run, and that's pretty cool.

Now all that is needed is for the technology to trickle down to the scale and price point that we need in small yachts. What could possibly go wrong?

Jim

[TrentePieds]

Did somebody mention that the distance these ferries run, slip to slip, is 2.63 NM - I say again: Two decimal six three nautical miles, and that the crossing time, and therefore the time twixt charges, is less than 20 minutes?

No, I thot not :-)!

The two vessels maintain a schedule that permits a departure from either side of the Sound every 15 minutes.

We already know that we are buggering about with 10,000V, right? That, I would think, is the reason for the robotic charging plug. But for the potential disaster being so serious, I wouldn't be able to wait for the control devices to go for a burton and the sparks to fly.


TP

[Jim Cate]

One should note that they have incorporated diesel power as a backup for the 'reliable' electric power. This makes good sense safetywise and isn't really a condemnation, but does cast a slightly different light on the (very interesting and positive) experiment.

Jim