Is diesel-electric or all-electric the future?

[moseriw]

Originally Posted by Nidnoi_V

Hi all here is the calculation i got from muliple websites



for Dielsel KW Saildrive compared to Electric KW a



Dielsel effectivness is 36,5% at the probs



the calcultation would then be the following based on 57HP Yanmar

(57*0,73549875)*1000 = 41,9 KW

at the prob that would be 36,5% of 41,9 KW =15,3 KW

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Uh yes yes as long as you fill in electricity like fuel.

Do not forget that the effort to produce electricity downgrades the calculation from 94% to < 50% - IN TOTAL

And the discussions are bloody useless as the production is very very complicated and not really effective.

To your calculation: I have a 62 kW Engine and I would not do it below 30 kW

but I consider it as bloody useless to throw out my good old vintage engine and slam in an E-Motor construction with a Generator that will cost me 35 - 45.000 USD for around 500 NM to go p.a.

It is very frustrating to see how people throw out the fact they erupt from their lower abdomen without any crosscheck on simple facts.

[moseriw]

With a well designed electrical system solar/wind can provide all the comforts (unless you need air conditioning)

Oh yes and my 2,8 m² (which is a good maximum on boats) panels have an indication for 36 Amps Peak. The truth in the med is 12 - max 19 Amps.

Yes Yes this will give me all the comfort I need.
12x10hrs= 120Amps/24 = max 6 Ah consumtion. Good enough for my fridges.
And IF yes if every day is a sunny day.

[Nidnoi_V]

Originally Posted by moseriw

---------------------------
Uh yes yes as long as you fill in electricity like fuel.

Do not forget that the effort to produce electricity downgrades the calculation from 94% to < 50% - IN TOTAL

And the discussions are bloody useless as the production is very very complicated and not really effective.

To your calculation: I have a 62 kW Engine and I would not do it below 30 kW

but I consider it as bloody useless to throw out my good old vintage engine and slam in an E-Motor construction with a Generator that will cost me 35 - 45.000 USD for around 500 NM to go p.a.

It is very frustrating to see how people throw out the fact they erupt from their lower abdomen without any crosscheck on simple facts.

an Electric KW is the same at 3 HK AND IF you don’t want to spend the money to go electric that is your choice i will spend the money however it won’t be just 30-40K but more in the range of 160-180K which will incl Solar etc. and also generator i do have a friend who sails on a 60" Catamaran they have sailed 6000 NM with aircon etc. and used a total of 20 Liter of Diesel for their Season but main part is we are all different and we all have different goals and my best guess in 1-3 years there will be many places where Electric/hybrid boats will be allowed to cruise into where Petrol boats won’t be allow and I know some areas now also require you to have gray water tanks

[moseriw]

Nidnoi_V

So you took enough money from poorer ones to spend it on bubbles.

If you really want to live with nature do not spend your money in new things unless theyare absolutely necessary. Buy an old boat and give it a new life.

My car is an old "stinky" diesel from 1996 and it is the best climate saver ever as other ones would have had 4 cars in the meantime. I saved nature 3 cars that have not been built on my behalf.

And if you want to get rid of the CO2 (Hype) at all than get rid of your pets as they are responsible for 30% of the food production which has a footprint that would cut our CO2 problem so to zero.

And be aware that E-cars affect our climate 50% more than Diesels.

UOHH NOT TRUE:
facts: statistcs say that the break even point diesel/e is around 240.000 km if you include ALL facts. (production a.s.o.) - But battery lifetime is not included.

Tesla gives you 8 years or 160.000 km warranty.
I do 10.000 km/year and expect the batteries 12 years and 120.000 km to go.

And now you got a + 50%

Do you think this does not effect your boat an especially your high tech batteries? I go with lead acid ... therefore!

Oh btw. I forgot one important thing. The recycling of high tech batteries is so expensive that the simply throw them away.

And these costs on nature are not even mentioned in any statistics.

[Corvidae]

Originally Posted by noelex 77

Waiting at a port for parts or a technician to sort out a problem is not luxury living.

Which is exactly why I don't like diesel engines. Electric motors can be repaired anywhere that has electricity. I can carry them out of my boat, by hand, without a crane. I can ship, or have them shipped, via UPS, not even freight. Any decent electrician anywhere can fix my motors, or I can do it myself. With parts from any source, not just one manufacturer that could be on the other side of the planet and bankrupt 40 years ago. I can easily, and affordably, store an entire extra motor next to my bunk, just in case. And replace it by changing 4 bolts.

Diesels have a few very large advantages, maintenance is by far not one of them.

And (unless you need air conditioning) is an incredibly big unless. Especially with current dual cycle AC/Heaters. It's the difference between where you can cruise without having to have an open fire on your boat, and what anchorages you can survive without a heat stroke. The point of going places is to enjoy them, and not suffer in misery while you're there.

[Pete7]

Originally Posted by valhalla360

If we were talking automotive engines, this would be a big deal. In stop and go traffic, they spend a lot of time idling, then hard acceleration, then cruising at speed, then braking....repeatedly. The engines are way oversized to provide for that hard acceleration and a ton of time is spent way outside of ideal operating speeds. A hybrid system that smooths out the load on the ICE has great potential to improve efficiency.

A cruising sailboat on the other hand, once you get out of the harbor, throttles up to cruise speed and stays there. Since the engines are largely sized for this load, they are up at near ideal output for efficiency. The potential benefits are much smaller and will typically be lost when you consider energy conversion losses.

This is the system Nigel Calder has been involved with and it was installed on Distant Sailings Southerly 42 I think. Capable of generating 9kw or something if the engine is just tickling along. So how come the 10kw of new AGM batteries to support it failed after 2 and a bit years? Ouch

Suddenly that Honda genny and an electric motor looks attractive.

[noelex 77]

Originally Posted by Corvidae

Which is exactly why I don't like diesel engines.

But the generator you advocate has a diesel engine (or less robust petrol engine). The generator is not just a diesel engine. It is connected to sophisticated electronics to generate stable AC power. Lots of proprietary parts. In addition, for propulsion to work via the generator and electric motor, you need a battery charger, electric drive motor, drive battery bank and motor controller. I don’t see how this multiple equipment combination is more reliable. A simple diesel drive motor seems easier.

Originally Posted by Corvidae

And (unless you need air conditioning) is an incredibly big unless. Especially with current dual cycle AC/Heaters. It's the difference between where you can cruise without having to have an open fire on your boat, and what anchorages you can survive without a heat stroke. The point of going places is to enjoy them, and not suffer in misery while you're there.

Air conditioning is a personal choice. At anchor with a well insulated boat with plenty of ventilation I don’t feel any need for the associated complication, but this is perhaps due to our Australian heritage. YMMV. If you do require air conditioning at anchor, a generator is a must (unless you have lots of solar and are happy with a short run time). Heating is different and is easily accommodated without a generator.

[Corvidae]

The generator I advocate is the least inconvenient way to get around solar/wind power generation limits. The combination of input and storage sizes are too big for a boat without a liquid fuel source. Gas generators work just fine too, my neighbor uses a Honda 2200 to push his 36 footer around for long hauls. It's just inconvenient to go that slow because it's small and not a permanently installed unit. At 10kw you get 80% of hull speed, at 20kw you'll get closer to 95%. Returns diminish rapidly after that, but I've seen 2000kw installations that the owner was very happy with compared to the original motors. Again in his case, it cut him from 3 diesel motors down to 1 larger one and a much simpler setup with no transmissions, just a couple VFD's and external pods.

The motor and controller are the only added parts that everyone doesn't already have on their boats anyway. Everyone has a house bank and a battery charger anyway. You're still going to have batteries wearing out and dying, or float cells to maintain if that's your thing. And as I said, the motor is dead simple to fix or replace, and has no maintenance. The motor controller is a sealed unit with no moving parts, and voltage/thermal regulation. It doesn't do anything and is dead simple to replace on the very off chance it does have a problem. Again, four bolts and a few cable connections. No specialists, cranes, or parts that have to be freight shipped. Although I'm pretty sure it will last longer than the rest of the boat.

[Dockhead]

Originally Posted by Corvidae

. . . At 10kw you get 80% of hull speed, . . ..

On a glassy calm, windless day?

What if you have to maneuver against a strong wind and head seas?

I had a 36' boat with 40hp, and that was barely enough to feel somewhat safe in not all that strong conditions.

An electric boat used for cruising (as opposed to day sailing) should have as much horsepower as you would normally have on a diesel powered boat. Now the good news is that you might not need all that power very often, and somewhat bigger electric motors are not normally all that heavy or expensive.

A 10kW generator however costs and weighs more than a 33kW direct drive diesel with marine gear AND with an alternator big enough to supply all possible domestic needs. This one: https://www.northern-lights.com/m843nw3g/ costs $19 000 and in fact weighs 335kg, a third of a tonne, way more than my 100hp Yanmar. No way it makes sense to buy a generator like that for diesel-electric propulsion. Once you have a diesel engine on board, it should be directly coupled to the prop shaft -- much more efficient, lighter, cheaper, better.

Conceivably a cat which could reduce the number of diesels from 2 to 1 might be an exception to this, but I'd still like to see the math.

The optimal diesel-electric arrangement on a cat, however, would probably not be series hybrid, but to have one prop driven directly and the other electrically, with only one diesel serving for both mechanical drive of one prop and electrical drive of the other/battery charging. You'd have to underprop it a bit (or better have a variable pitch prop) to avoid overloading the engine when the generator is working at full capacity, but this could be a neat arrangement, saving a significant amount of weight but with full efficiency of direct drive through one prop for longer motoring passages.

Might even be cost effective. For a cat which would normally be equipped with 2x 40hp motors, have a single 40hp motor driving a variable pitch prop plus 10kw (or so) generator head. Electric motor in the other hull of say 33kW. You would adjust the prop pitch according to EGT to prevent overloading. If you wanted to, you could run both props at the same time, with burst power of 80hp, with difference between 10kW and 33kW for the electric propulsion motor made up out of the batteries. That could be a viable arrangement with some pretty interesting advantages. Two issues to solve would be (a) the prop -- Hundestad makes manually variable pitch props, but smallest one, IIRC, is for 160hp; (b) the generator head drive. I guess these should be solvable somehow.

[HappyRock616]

Originally Posted by Lepke

I've run a number of diesel electric vessels. You'd need a huge, expensive battery bank. Overall it's not as efficient as direct coupled engines. My guess is you'd spend as much for a small diesel electric conversion as all the fuel used in the lifetime of the average boat.

This make sense! I would argue if you already had a sailboat in the 50+ ft range, where the engine is an auxiliary and you probably have a generator this could make sense for a re-power.

I love the idea in general, it would justify lots of house battery capacity but still allow for long range if you ran the generator. Plus with an electric motor drive, there is some real potential to regeneratively charge. If you're in the tropics you could solar charge the bank over 2-3 days time with no diesel consumption at all.

But I agree, I think there is a factor of scale. I'm not sure this would be economical or have space in a 30-40 foot boat.

[jojolimited]

Here is a youtube channel I've been following for over a year. An experimental catamaran powered by wind, solar, and hydrogen. They process their own hydrogen from seawater. The boat is called Energy Observer, the channel is available in both French and English.

https://www.youtube.com/watch?v=yWWYiDTVbRY&t=1s

[lightguy]

My comment from the peanut gallery;
54' Alibi catamarans originally produced by design all electric propulsion systems in 2010.
These are performance cats not the big luxury ones.
Perhaps things have gotten more efficient but many owners have retired the electric motors and replaced with diesel engines. At considerable cost so there must be a good reason.
The one that is currently on the market has NO solar panels which I find quite odd in a boat originally intended to be all electric. Shore power charging or aux generator to provide electricity ??
One more consideration with a catamaran and especially a performance cat is weight.
I would assume "heavy" monohulls could absorb the additional weight penalty of big battery packs much better than that on cats where weight is an absolute killer of speed.

[WhiteHill]

I have absolutely no affiliation (and nor would I buy one, even used):
https://www.salonayachts.com/yacht/15/46---xlvi

[mcon12000]

Just a few personal observations on the subject.

All electric is really attractive but just not practical for my use where long distances with some time considerations are involved. Or rather I don’t day sail and I move along the coast via the ICW when outside conditions aren’t great.

I’m huge fan of things moving in this direction but it’s going to take some advancements in storage and the speed at which it can be replenished. I dream of the day I only need half the panels I have now especially since I’m a mono hull.

Another reason why EV’s are the future isn’t directly related to the overall emissions but rather the number of moving parts involved. I think this is an important point that gets lost in all the conversations about range and charging.

[WhiteHill]

“Jimmy, your concept may be right but it is premature......"
https://cornellsailing.com/2020/12/electric-shock/