Going electric - change my mind

[GrowleyMonster]

Originally Posted by Rumrace

An electric motor makes one heck of a generator. An electric motor on a clutch or 2 speed clutch or with its own lay shaft in the transmission by be a great long range step. When the diesel is used it would have to contend with power robbing motor or a clutch to disengage it.
I think one difficulty going forward is motor cooling. Electric motors want higher water flow over a larger surface. I’ve sern several lame electric outboards with no cooling. While a trolling motor on a bass boat may escape the need no running motor does.
Some electric motors have liquid cooling sleeves available they incorporate a pump off to one side.

Actually, no. With regen turned all the way down to zero, there is almost no parasitic load from the electric motor. The reason to have a clutch is to save the motor bearings and drive belts from nonproductive wear.

One can make a very strong case for air cooled electric motor. It is simple and cheap. I considered water cooling before it was even a thing, and discarded the idea as an unneccessary complication. I did swap out my original 5kw motor for a 12kw motor, though, mainly for better heat dissipation, but I very seldom ran my system at full rated power even with the 5kw motor and 300A controller, and most eboaters won't, especially if the eboat is also a sailboat.

BTW I might remind you that the OP was asking about straight EP, not hybrid. Not only is hybrid systems off topic, but for the average yacht owner, the engineering involved would be wildering. The concept is simple and brilliant. The reality is complex. If it was simple, wouldn't you already have a parallel hybrid drive boat?

[Dieseldude]

Originally Posted by s/v Jedi

Sorry, most of what you write here is wrong. Your username seems to indicate you are not open minded and just here to argue, which is senseless so even though my fingers itch for pointing out the errors, I won’t respond to these posts anymore.

You have nothing to say on logic, so you attack the name that I happened to pick many months before this particular discussion arose. Do you really think that many months ago I knew that a discussion about electric and diesel propulsion would come up now? Oh but you tap into "the force" so maybe you know the future. Who is really the one who is here looking to argue?

[Bullshooter]

Originally Posted by sailingharry

I was a bit tongue in cheek. I think Tesla rocks. ...

Oops, i had an irony deficit! I misread your meaning there.

[Adelie]

Originally Posted by sailingharry

CDCorl,


I've often pondered electric for the dinghy. My biggest concern after speed (we just upped our 8 to a 9.8 because the 8 won't quite plane our 8.5 aluminum RIB) is recharge -- we anchor out 95% of the time, sometimes for many weeks on end. Battery charge for the mother ship is an unending concern.


You have just come from daily use in an area where shore power doesn't exist (I have limited experience there, but that's my understanding). How did you handle recharge? I would expect that adds 50-100Ah/day of power to your budget, is that about right? That would be at least 200W of solar just for the dink, I'd think (our current solar is maxed out at 700W, but yet to exceed 400W output).

Did you try putting a flatter, larger diameter prop on the 8hp? It increases thrust for the hole shot at the expense of max top speed.

Elco has a 9.9hp electric: https://www.elcomotoryachts.com/prod...tric-outboard/

Requires 48v so you would need 4 small (30-50Ahr) LFPs. 4 large (100Ahr) would would for extra range but would eat into the available dinghy volume.
Even with the larger batteries I’m not sure how much range you would get. I’ll research this a bit.

For recharging I would mount 2 or 3 30w 33v panels over the motor on the stern. They would be charging the batteries whenever the sun was up but probably not more than enough for 30min on a plane.

Another option is to go with mixed power. Keep the 9.8hp gas motor and add a 46-50lb thrust trolling motor. Electric to go to and from the near shore and other nearby destinations. Gas for long distance destinations.
Mount 50-100W panel over the motors at the stern.
Other members here that have done this indicate that 50W was enough to keep up with power needs for all short and medium destinations.

[Adelie]

Originally Posted by NPCampbell

…..



Also, the input voltage for this pod is listed as 39-60v. Your battery pack will have to be in that range or you'll lose 10% with a DC-to-DC converter. If your battery pack is setup for the high motor voltages then you'll lose the 10% with a buck converter to drive all of your other house loads unless you add more batteries.



….

39-60v covers the entire range of a 48v nominal battery from completely discharged (39v) up to battery charging while almost full battery (60v) which is also the cutoff voltage for “low” voltage installations. Above 60v higher voltage safety regulations kick in, this is why you don’t see any 60,72,84 or 96v systems offered for the marine recreational retrofit market.

[Amazingrace1]

Originally Posted by SaylorMade

Alright, I have a 27' sailboat from 1984, with a Volvo Penta MD7B seawater cooled, Saildrive 120S.
The saildrive has multiple issues, and the engine is running without a thermostat, since no one has been able to figure out why it fluctuates wildly in temp with one installed.

I use it for weekend trips and summer holidays, almost always shore power at night, and max 25 nm per day.
I usually use around 20 litres of diesel in a season.

I love the boat, gonna keep it, but something has to be done - propulsion wise.

The boat was originally sold with an 8 HK diesel, even though mine was delivered with an upgrade: MD7B (14 HK). I have never been close to full throttle with it. Normally runs around 1500 rpm giving me 5 knots.

I've been quoted (albeit no one seems to give exact quotes anymore) around 20,000 USD for a new installation of a Volvo D1-13 with S130 drive.

On the other hand I'm looking at an electric propulsion system from ePropulsion. 6 KW pod motor with a 9KWh battery pack and charger. (Shore power remember).
That will be around 15,000 USD including the work done to close the saildrive hole in the bottom of the boat.

So I can save money, and have a what seems to me to a much less complicated system to maintain. Not a plethora of things that can go wrong: generator, pumps of different kinds, fuel contamination, cooling issues etc etc.
I also like the idea of hearing a lot less noise when motoring, and would be happy to trade 1-2 knots of cruise speed on that account.
With the 9KWh battery it will give me plenty of range for the very few becalmed days - as I said, if I am able to sail in almost silence, 3-4 knots is fine with me.

Sales value is not an issue for me, I will keep the boat, and I don't expect to get anything for it when I stop sailing.

So, I'm very close to "add to cart" on the electric system - but I want to hear if I am missing something in my thought process here?
So - go ahead - change my mind

Some info:
The boat: https://sailboatdata.com/sailboat/nordship-808

The engine: (6.0 EVO) https://www.epropulsion.com/pod-drive/

The battery: (E175) https://www.epropulsion.com/e-series-batteries/

I think you will love going electric. I converted a 1978 Columbia 10.7 from a Yanmar to an electric system i bought from Electroprop | Home


The quiet, clean cruising is truly delightful. We got rid of Amazing Grace and no longer get on the water (wife has brain cancer). Do it!

[alamoana]

Before spending that amount of money I would try to solve the current engine problem, but then I look for difficult projects!

[Na Mara]

The EU parliament just voted to ban the internal combustion engine in personal transport from 2035. If the council backs them (which looks likely) no new ICE vehicles for private or light commercial use will be sold in the EU from 2035. How long until ICE engines are banned from pleasure craft?

I think the diesel I have aboard will be my last diesel.

[Dieseldude]

Originally Posted by Na Mara

The EU parliament just voted to ban the internal combustion engine in personal transport from 2035. If the council backs them (which looks likely) no new ICE vehicles for private or light commercial use will be sold in the EU from 2035. How long until ICE engines are banned from pleasure craft?

I think the diesel I have aboard will be my last diesel.

Another government over reaction that will cause major disruption and catastrophe if it proceeds. Currently, there exists no viable alternatives to conventional engine vehicles in all applications. Existing EV's are really only useful for short range transportation. It is not known if battery technology will be improved sufficiently by 2035. Less than 13 years to develop such a technology and put it into wide spread service does not seem like something to stake the future on. Even if accomplished, without asphalt as a by product of petroleum fuel, wonder what future EV's will drive on? Even concrete as pavement requires large amounts of coal or gas to produce. Wonder where plastics used as EV components will come from with petroleum production shut down? I would not bet the boat engine on electric propulsion.

[Na Mara]

If they no longer sell marine diesels for leisure craft after 2035, and no longer sell the fuel for same after say 2045, then it really wont matter what I think about the practicality of going electric. Even long before that deadline you would be more or less stupid to spend 20000euro on a a dying soon to be obsolete (in the sense of no longer supported) technology when considering a repower.

[goboatingnow]

Originally Posted by Dieseldude

Another government over reaction that will cause major disruption and catastrophe if it proceeds. Currently, there exists no viable alternatives to conventional engine vehicles in all applications. Existing EV's are really only useful for short range transportation. It is not known if battery technology will be improved sufficiently by 2035. Less than 13 years to develop such a technology and put it into wide spread service does not seem like something to stake the future on. Even if accomplished, without asphalt as a by product of petroleum fuel, wonder what future EV's will drive on? Even concrete as pavement requires large amounts of coal or gas to produce. Wonder where plastics used as EV components will come from with petroleum production shut down? I would not bet the boat engine on electric propulsion.

Short range ?? , given the latest have 750 km ranges that’s as much As most petrol tanks hold. People don’t drive like this in general anyway

Certainly for car transport EVs will sweep the board ( as a ev owner id never go back )

[Dieseldude]

Originally Posted by goboatingnow

Short range ?? , given the latest have 750 km ranges that’s as much As most petrol tanks hold. People don’t drive like this in general anyway

Certainly for car transport EVs will sweep the board ( as a ev owner id never go back )

Great!, But what is the range of the latest ones at -20 degrees C ? What is the range at over 20 degrees C when the AC is running? What is the charge time? What will be the cost of new batteries, including installation, when the originals get tired? The sales pitch always neglects the draw backs.

[Renegde_Sailor]

Originally Posted by SaylorMade

So, I'm very close to "add to cart" on the electric system - but I want to hear if I am missing something in my thought process here?
So - go ahead - change my mind

There is a beautiful Ingrid 38 sitting next to my boat in the boat yard where I am doing my refit right now, the boat in the time I have known it has had 4 owners.

The reason is, the boat has an electric drive, despite being an excellent sailboat, in modern times if you are a day/weekend sailor, too often you are relying on the engine to get home on time so you can get back to your 9-5.

Unless you have a super flexible schedule, you're going to hate the electric drive when the wind quits.

[Renegde_Sailor]

Originally Posted by goboatingnow

Short range ?? , given the latest have 750 km ranges that’s as much As most petrol tanks hold. People don’t drive like this in general anyway

Certainly for car transport EVs will sweep the board ( as a ev owner id never go back )

a 750km range on an electric drive is going to have to have a massive battery bank which is going to cost massive $$$$$$$$

[Pete7]

Originally Posted by Renegde_Sailor

a 750km range on an electric drive is going to have to have a massive battery bank which is going to cost massive $$$$$$$$

So you find yourself appointed as the Minister for Transport of a mid sized European country. The EU requires that its your job to get rid of new ICE vehicles in the next few years, no excuses just do it, oh and they are watching. Your plan is what exactly?

Now what about those old polluting vehicles still around? Since fuel duty amounts to 57% percent currently and your Gov doesn't need to do squat to collect it, the retailers do it for you. Would you raise the tax each year to encourage the populace to progressively switch with a few grumbles? Or would you risk being voted out by introducing another new law or unpopular tax.

We are seeing £2 a litre today, that's $8 a gallon. What will the line on a graph of fuel prices for the next decade look like? A steep mountain perhaps?

And leisure boats, will they just be caught up in the dash to electric or will you Gov make exceptions so rich yachties can continue to motor around polluting the seas whilst road users do their bit. Hmm that's a vote winner, not.

Thank the lord we have a 31ft yacht that sails rather than a 31ft motorboat with big twin diesels at 30 gallons an hour.