Replace Diesel with electric engine

[captqrunch]

Doing the ICW strictly under sail would be dangerous, IMHO. And rude. Dangerous because many stretches of the waterway are quite narrow and quite heavily trafficked, and much of the commercial traffic, i.e. entrained barges, cannot maneuver out of the way of a sailboat which might be becalmed in mid-channel. Furthermore, as they pass abreast of the sailboat in a narrow channel, they generate suction that could pull the sailboat into the side of the barge. Rude because vehicular traffic waits on the sailboat slowly transiting the swing bridge; ruder still if the current sweeps the boat into the bridge, entangling it in the structure. Sure there are places where these scenarios do not apply. There are also a number of inlets where strong currents make sailing imprudent unless one has local knowledge of the currents and bars.



I made the trip from Ft Lauderdale to Boston, up and back, years ago: I sailed offshore for the most part, ducking in to avoid frontal passages and Cape Hatteras. No way would I attempt the ICW engineless in anything larger than about 30 feet. I was surprised to find I spent much more time under power than sail, both ways (I also motorsailed when necessary to reach shelter before frontal passages as I had two young children aboard.) I notice that the very experienced YouTuber who cruises on an engineless Southern Cross 31 does not attempt his seasonal North-South migration "inside." In my opinion, it is folly to permit one's ideology to override the dictates of prudent seamanship. If the opposite of Green is Red, then better Red than dead.



That said, I do believe combustion engines should be banned from lakes that supply public drinking water. Electric propulsion is perfect for lakes.

[stevenm2016]

My 2 cents on the topic. I have personally installed a number of large lithium banks on sailboats. Mostly cats, but the concept is the same. These average 1800ah and will be helping install a 1920ah system this weekend. Solar has been anywhere from 500w to 2000w.


I have looked at electric propulsion many times and my current conclusion is that it doesn't make sense, YET


What does make sense and what is very green, one owner ran his genset 9 hours a day. For AC while sleeping and for heavy cooking. With that same 9kw genset, he now runs it for 3 hours once a week, just to charge his 1800ah bank. He went a month without his genset running because he didnt use AC for a month, nor did he have to run his engines for alternator charging.



For those that like creature comforts, a decent battery bank, genset and solar is extremely green and helps reduce the noise factor.


An Amel is a big boat with many creature comforts. And we are often on the hook and not moving. The primary function of all that battery is to go as many days as possible without the need for a genset or running the engine to charge the house bank.


A mono has s!@t for space for solar. The goal is to have the house bank charged for when you arrive at your destination. Hydro-power and a decent alternator are great for that.


I dislike the engine noise and would love to get rid of it. However, when under way, I want to get to my destination which probably will need some level of motoring.


We really need to understanding what is green. A week on the hook and not using consumables is great. A week in a marina with high electricity rates and not having to plug into shore power is great.

[JHW]

I know electric systems have evolved but having owned on for 5 years I am very pleased to have a strong Diesel engine. I like to anchor out partly due to the quiet. Running a generator to top off the batteries was not only noisy to me but also any neighbors. I did not have the power to push into 15 knots of wind and batteries went down rapidly in any attempt to do so. Always had concerns about battery levels. All of this went away with the diesel. If the system broke, no locals had the knowledge to fix and parts were not available locally. It is a lot of current which can be the cause of problems also. My system was installed by Solonmons technology, who made the motors for the Moon Land Rover. But I was once blown off my boat. I feel electric is evolving but just looking at your drawings is an indication your proposed system is heavy, complex and a space hog. The only pluses was the quietness of the system and lack of fumes.

[Mauruuru]

Actually the only benefit is not quietness. Lets start at the beginning:
The first forms of motive power not using animals was electric, not diesel (next) or gasoline or another fossil fuel. It didn't succeed for two reasons-inadequate energy storage and DC motors.
Its been a while since thermodynamics but lets assume that the IC engine is max efficient at conversion of fuel to power-its not-that would be 30-35%. A modern Permanent Magnet AC motor is capable of 92%! What has enabled this transition back to electric motive power sources are 1) improved battery chemistries with better life cycle cost and higher power densities 2) the biggest change is power electronics which allow for frequency modulation of the speed of an AC motor at high DC current input.
The electric drive provides an essentially flat torque curve from 1 rpm to max motor speed meaning maximum transmission of power from the source (a 92% efficient motor lets say) to the propeller. This allows a motor of 1/2 to 1/3 of the kW of the equivalent diesel to drive a sailboat to hull speed at max rpm of the prop (1600 rpm) not the 2500 rpm of the diesel engine. Total cycle efficiency is dramatically improved. If using regeneration while sailing, for about 1 kt of boatspeed you can recharge your batteries for free even in light winds though in heavier airs you get more than you need to both move at hull speed and recharge the batteries on a long sail. Coupled with solar, wind, or a small generator makes the "system" as go anywhere as any diesel or gasoline engine ever was. And added benefits-yeah no noise, no fumes, and very little maintenance for a quality designed and built system-an AC motor will last longer than the fiberglass boat with zero maintenance as long as its thermal and thrust ratings are not abused.
So expect to see many more electric sailboat auxiliaries (as well as cars, trucks speedboats, and airplanes).
But hey, no one will make you do it!

[moseriw]

Electric engine. Good Idea if you want to reduce your range to 20 NM.
Otherwise you run a 20+ Kw genset all the times. (Not on current but on DIESEL)

[Mauruuru]

and I thought someone flew a solar plane clear around the world!

[Mauruuru]

false data does not an argument make

[Happ]

Originally Posted by norbu09

Hi, I am new here, please let me know if I post in the wrong spot or make any other rooky mistakes

We live on an Amel Super Maramu in La Rochelle, France and work through our refit at the moment. We planned to go cruising soon but the diesel died so we are now looking at an electric conversion. We did toss many ideas around and landed on a system that I hope is easy to work on, easy to find parts for and good enough to get some first experience. Then, over the coming year, we plan to build out the system so it is fit to sail us home from France to New Zealand.

The system is built around a 48V Lithium battery bank that will service the boat needs and the engine. I have some initial drawings around the idea and would love to get feedback from those who have built systems like this.



The drive system will most likely be a oceanvolt AXC which runs on 48V.

The plan for the battery bank looks like this at the moment:



cheers
Lenz

12v 100amp lithium batteries run just around $950. 75 batteries will cost you around $70,000. The young sailors on Sailing Uma with a 48v electric motor on a 36’ Pearson. They spent about $12,000 for batteries and assorted materials and so the install themselves. The result is they get about 5.5 knots for 2 hours. Some info you may want to think about considering the size of your Super Maramu and the engine size with it’s demands.

[Mauruuru]

If electric propulsion was ineffective the US Navy wouldn't be repowering ships and building new ones with it. Running a diesel genset at a constant RPM gets the best possible performance out of IC engine (30% maybe). Using electric drives gives the vessel immediate response to speed inputs and direction.

[Poche]

Originally Posted by Mauruuru

and I thought someone flew a solar plane clear around the world!

Non-stop?

[Poche]

I would look at this for getting in and out of a harbor for a day sail on a small boat or a short trip to our closest island. It would probably be too expensive to justify that.
As far as cruising, electric propulsion is not going to replace a well maintained diesel any time soon when the technology changes somehow.
Some say running a generator with electric propulsion works but giving up a diesel to run a generator doesn't seem to make sense.
Also, can you imagine being somewhere and the shipping cost for batteries if a replacement is needed?

[skipmac]

Originally Posted by Mauruuru

and I thought someone flew a solar plane clear around the world!

They did. Had huge wingspan, was outrageously expensive, extremely fragile, all surfaces covered with solar and barely enough room and load capacity for two pilots.

Average speed 45 mph, took over 500 days.

Great for getting into the Guinness book but not even close to practical.

[skipmac]

Originally Posted by Poche

Non-stop?

No. I think they stopped every night. Took 505 days

[skipmac]

Originally Posted by Mauruuru

Actually the only benefit is not quietness. Lets start at the beginning:
The first forms of motive power not using animals was electric, not diesel (next) or gasoline or another fossil fuel. It didn't succeed for two reasons-inadequate energy storage and DC motors.
Its been a while since thermodynamics but lets assume that the IC engine is max efficient at conversion of fuel to power-its not-that would be 30-35%. A modern Permanent Magnet AC motor is capable of 92%! What has enabled this transition back to electric motive power sources are 1) improved battery chemistries with better life cycle cost and higher power densities 2) the biggest change is power electronics which allow for frequency modulation of the speed of an AC motor at high DC current input.
The electric drive provides an essentially flat torque curve from 1 rpm to max motor speed meaning maximum transmission of power from the source (a 92% efficient motor lets say) to the propeller. This allows a motor of 1/2 to 1/3 of the kW of the equivalent diesel to drive a sailboat to hull speed at max rpm of the prop (1600 rpm) not the 2500 rpm of the diesel engine. Total cycle efficiency is dramatically improved. If using regeneration while sailing, for about 1 kt of boatspeed you can recharge your batteries for free even in light winds though in heavier airs you get more than you need to both move at hull speed and recharge the batteries on a long sail. Coupled with solar, wind, or a small generator makes the "system" as go anywhere as any diesel or gasoline engine ever was. And added benefits-yeah no noise, no fumes, and very little maintenance for a quality designed and built system-an AC motor will last longer than the fiberglass boat with zero maintenance as long as its thermal and thrust ratings are not abused.
So expect to see many more electric sailboat auxiliaries (as well as cars, trucks speedboats, and airplanes).
But hey, no one will make you do it!

Seems like you are ignoring the fact that with current battery technology and indeed battery technology for the foreseeable future, all of these applications will be limited to a few miles in range unless you add a large, diesel generator to power them or a small barge full of batteries and solar panels to tow along behind.

Neither option too practical for an airplane and not cost effective or practical for the other applications you mention. Sailboats, yes if all you need is to get from dock to open water.

[Happ]

Originally Posted by Poche

Non-stop?

They did fly a plane around the world. They often were stopped for months rebuilding the aircraft. Then they waited for the perfect weather for the next leg. In addition the plane was a test article only. It carried no payload and could barely stay aloft at the minimal air speed it flew.

When battery technology improves and becomes cost effective I believe it will be the way to go. Cars started out with less than 50 miles to a charge. The latest technology is promising 300 miles per charge.