Using Nissan leaf as engine / battery donor for my boat

iomusicdublin

I have a Dutch barge and I would like to convert it to full electric power. Has anyone here experience of doing it.

iomusicdublin

Anyone?

The boat is a 62ft x 13ft Dutch sailing Skutsje Tjalk

like this

cros13

Torqeedo have some equipment options (although admittedly pricey). They even sell i3 batteries (though at 10 times the price of salvage).

https://www.torqeedo.com/en/products/

Even if you're planning a DIY solution it's worth looking at how the commercial guys have implemented things.

bonky2018

I have installed several 10HP to 40HP diesel inboard engines to boats from 25 to 45 feet long and repaired engines from that size up to 150HP in larger boats up to 70 feet

Several times some sailors would inquire to convert to electric and when we gave them the quotes even sourcing second hand salvaged stuff they all backed out as the costs were just too high.
We fitted some small electric drive impellers for bow thrusts but these are very small powers and most boats prefer the hydraulic systems driven from the main engine

A barge like this if it is made of wood such as carvel construction would often be too wet inside to safely do high power electric.

If it is steel hull the excessive weight of the steel could make power demands very high

Many marinas electric power often isn't so good for recharging large battery packs

One problem that often pops up is the props to get better efficiency with electric tend to be much larger and turn more slowly with needs for gear ratios that dont tend to exist from off the shelf .
This often causes problems in slower speeds requirement and for more hull clearance from hull with larger props
Also there can be extra drag from larger props when under sail and the engine is turned off .

Weight impacts the speed and performance of sailing boats and larger battery packs are often a weight issue.

Ranges of electric drive boats often are very much less in nautical miles than similar diesel powered boats

Normally for electric power for boats the parameters are worked out first and then the hunt is made for suitable power units.

In this case the power unit has been chosen to suit this boat where the parameters are not stated

Typical parmameters are range speed cost weight

The sail boats parameters often results in electric conversions being more suitable for small sail craft typically less than 25 feet long who require ashort range of few nautical miles to return back to port after a short distance local sail .

The power density of lithium electric batteries in this time is not much more than 2% of that of diesel fuel

The magic number batteries want to get to is 400 watts per kilogram to start to match diesel fuel and most lithium struggle to even exceed 150 watts per kilogram n this time


A hybrid solution where some sort of diesel engine runs the electric power is more likely to work in larger boat projects keeping the size of battery of down in costs and weight .
Example where a boat needs to use electric power to maneuver and not risk engine cutting out issues such as inside a busy harbor
That might justify the extra premium costs of electric power or Hybrid solutions

Certain rivers and lakes demand only clean or electric power for boats so as to not pollute the waters.

Switzerland lakes have very strict rules for lake boats and so are often the big users of electric power for boats

Some cargo type sail boats require ballast so replacing the dead weight ballast with heavy lead acid batteries types might not impact the weight factor so much compared to light weight sailing racing crafts .

So the real question is this to be project to replace ballast and get more economic fuel performance
Is it a project which just requires to be able to rest at anchor for many days and not have to run a generator to recharge the batteries
Is it some mix of requirements and you happen to have a scraped LEAF you want to use to solve the problems you have .

Certainly owning a 60 foot boat is a economic problem even just repainting it every year costs big money .

Motoring with a large diesel engine in the 60HP plus range at 5 to 6 knots knots (6 t0m 8mph) often will require one gallon to get 4 miles at best case and probably more like 2 MPG in calm conditions and worse going against the wind

Hybrid and electric power will be less likely to solve that issue of cost of moving a large boat like this on open sea ways

There might exist some saving using hybrid or electric power solutions in canals and rivers in certain limited conditions .

There is a need for more info what the requirements are ??? before I can input any useful facts that might help your project


Bear in mind the LEAF electric car going at 50mph only develops some few kilowatts of power to drive the car at that speed
That low power tends to suggest the power pack is more suitable for smaller 30 to 40 foot long sail boats.


If the LEAF parts are best for the boat project once a suitable prop and prop shaft are fitted correctly then it more likely that one of the forums where there is DIY electric car conversions will have the experience and knowledge base to fit the leaf battery and engine in correctly .

In the case of that type of low to the water bardge a outboard engine leg solution might also work well if it is to be used in calm waters or rivers canals and lakes

bonky2018

Here is link for smaller version of the boat from 1897 era so 100 plus years old about 50 feet long 15.7 meters dry weight 14 tons with 46 BHP inboard and not cheap at £125k for rust bucket eeeekkk

search google
(appoloduck " Historic Liveaboard Dutch Barge " 15.7m £125,000)

cant post links yet so the link needs to include the missing componets
//: dot dot / dot
http barges apolloduck com boat phtml?id=533496

It suggest your 60 foot boat would be dry weight 25 tons plus if made from steel or about 18 tons if it is made from wood

The more likly engines would tend be 45 BHP up to 100 BHP with probably the 80 BHP being the favored sizes for that size boat

A nissan Leaf power plant could struggle to move that boat 60 foot long 20 plus ton boat when fully loaded up maybe more than 30 tons with any headwind or counter flow direction from river or tidal currents.

Keeping the LEAF power plant from melting down into a blob of molten metal could be the bigger challenge if the LEAF engine power unit system isnt part of a diesel electric Hybrid power solution .

cros13

bonky2018 wrote: »

A barge like this if it is made of wood such as carvel construction would often be too wet inside to safely do high power electric.

Depends on the equipment used. The BMW i3 pack Torqeedo use is designed and tested to operate submerged if required. Complete with redundant seals and pressure release valves.
Rapid charging the battery while submerged is even part of the standard testing procedure for the i3 pack during manufacturing.

Of course galvanic corrosion needs to kept in mind. Otherwise the pack itself is fairly resilient.

bonky2018 wrote: »

The power density of lithium electric batteries in this time is not much more than 2% of that of diesel fuel

The magic number batteries want to get to is 400 watts per kilogram to start to match diesel fuel and most lithium struggle to even exceed 150 watts per kilogram n this time

True, I don't think we'll see wide scale movement even for leisure craft until 400Wh/kg.
That point is not as far away as many people think. Most probably in the next 10 years.
For the record the i3 pack cells are ~180Wh/kg and 24kWh Leaf packs are 140Wh/kg.

bonky2018 wrote: »

Bear in mind the LEAF electric car going at 50mph only develops some few kilowatts of power to drive the car at that speed
That low power tends to suggest the power pack is more suitable for smaller 30 to 40 foot long sail boats.

The Leaf pack can sustain ~40kW continuous or just over 130kW for 10-20 seconds (but won't be particularly happy about that kind of use long term).
It's not as well sealed as the i3 pack. Weight is 295kg. A salvage Leaf pack is about €2000-3000.

The i3 pack is a different beast. Sustained power from the 34kWh (which is what Torqeedo use) is 60kW (just under 2C) continuous or 245kW (just under 8C) for up to 10 seconds. The i3 pack can optionally be cooled with a gaseous refrigerant and has both an internal compressor and an internal system of perforated flat pipes to distribute and collect coolant. Weight is 255kg. A salvage i3 pack is about €3000-5000. Torqeedo want €30k for a new pack but provide a 9 year warranty for leisure marine use.

For an 80kW motor two packs of either would need to be fitted. A 40kW motor would be fine with a single i3 pack, but I'd be nervous about the Leaf pack.

Both the i3 and Leaf pack are 360V packs.

bonky2018

@cros13

The marine world suffers from many ailments that tend to stop electric conversion projects rapidly

The biggest factor is the price for some diesel engine solution might be lets say 10k new and the electric project is say 30K
Then the big question is the product guarantee and the electric project to cover themselves from issues like misused equipment and corrosion has to bump the price up to 60k to cover all risks .

Then there is the second hand salvaged equipment solutions lets say 5k for diesel solution second hand and same for electric solution 15k for electric solution .
Often the 2nd hand diesel solution will include some element of guarantee for work and parts and electric solution will often have no guarantees for any elements of the product solution

Result is the diesel solutions win nearly every time .

The few electric projects are often diesel engine driving a generator that drives electric motors for some technical reason like the engine can be placed any where in the boat to get some advantage .
In that case there is often no battery component involved

Electric conversions on 25 foot sailing crafts tend to be 72 volt solutions using golf cart lead acid solutions giving ranges of 7 to10 miles in flat out use of 4 to 5 knots (5 to 6 mph ).
They often motor out a couple of miles do a race or cruise then motor back a couple of miles .
It is often a copy of the DIY electric car conversion with 72 volt solutions that goes 25 miles at speeds of 50MPH in small to medium sized cars
with 12 of the 6 volt 100 amp to 180 amp golf cart batteries .It coverts into boats to equal about 8 to10 BHP

In 25 foot boats the normal diesel use often uses 10 bhp diesel engines and they typically use some 1.5 liters per hour at 5 knots ( 5 to 6 mph ) and that is about 12 to 15mpg
however if there is head winds the speeds drop down and the MPG can go down to 6 to 8 mpg
In more severe conditions the props exiting the water and waves hitting the bow slowing the boat down means speeds can be less than 1 MPH and MPG can be awful .Throw in strong tide current of 1mph and your not moving at all motor on and turn of engine and your going backwards .

Doubling the BHP of engine to 20 BHP can help that 25 foot boat but fuel consumption and cost go up a lot and it often requires larger props which create drag in sailing modes
Also extra weight can impact sailing performances exponentially.

A high performance 55 foot deep keel boat with a 120HP engine with leeward shore protecting the boat from much larger waves in severe winds of 60mph plus with all reefed sails on and engine on flat out was unable to for 24 hours to gain the one mile it needed to get inside the port
It had to tack for 24 hours outside the harbor until the weather calmed down .
That burned a lot of fuel with that boat typical requirement of less than 2 mpg.

Even todays electric solutions to repeat 24 hours of 120BHP would have battery that that would be huge compared to a 120 bhp diesel solution .

So without a design spec range weight cost and expected uses such as canal use only it isnt just a direct BHP replacement issue

Propellers are often only 70% efficient in calm seas and can lose a lot of grip when there are larger choppy waves dropping efficiency down to less than 50% . These factors make even diesel engine solutions hard to figure out and electric solutions are even worse to figure out

Then there is where do you recharge the battery ???
Often the solution is a diesel generator which feeds the next question why not do hybrid solutions or better still save weight and cost and just do diesel solutions.

Very few sailors then want to sit on top of of 300 plus volts with sea water conducting that power when they spring a leak.

Thats tends to mean that many electric solutions prefer to remain less than 100 volts and that creates all sorts of problems in high amps and high losses if the boats are larger than 25 feet .


Boats tend to have a maxim speed the water line speed based on length of the water line
Example top speed for 16 foot water line boat is approx 5 knots about 5.5 mph
25 foot water line is approx 6 knots
36 foot water line is approx 7 knots
48 foot water line is approx 8 knots
60 foot water line is approx 9 knots about 10mph

120 foot water line is 10 knots etc

Typically power demands for half the water line speeds are often fairly low but as the speed increases the power demands up to maxim water line speeds grow exponentially

On a 60 foot boat some 30BHP would probably be ok in calm waters to drive that boat at 4 knots which is about half its water line speed.
Thats about 6 liters per hour or gallon and bit an hour or about 3 mpg . However to stop a 60 boat with only 30 bhp it will take long time in reverse So 60 foot boats like engines to be larger like 80 BHP or 120BHP or even 200 BHP plus to give them stopping power and acceleration power and ability to steer when pulling away and then later ease back on the throttle to go into economic speed mode of slowwer speeds like 3 to 4 knots
However to go for full water line speeds like 8 to 9 knots it might require more than 120BHP depending the hull types and fuel figure of less than 1/2 mile to the gallon are possible . Power and fuel demands can go exponential the faster you go towards the water line speed the famous brick wall for hull displacement non planing type boats

To double the speed could require a exponential increase in power of 4 to 12 times as much power depending on hull shapes and types

So typically for canal use speeds of 4 knots are possibly enough and 40 BHP is maybe enough to fight the headwinds in canal use .
However on open waters it might require more than 80 BHP to go at 4 knots against a stiff wind and possible adverse currents for 60 foot long
boat

So information on intended sailing grounds would be interesting to know to spec out electric replacement demands .

Harbors which can supply electric power supply to recharge the battery at more than typical 6 amps at 240 volts would be another issue to look into .

Many issues to look at

I think the 30k for a new i3 battery is looking fairly cheap compared to many other factors when you run the numbers

At least you would get good cooling systems with i3 battery which LEAF battery dont do cooling the battery

Also these projects often the salvaged battery solutions are often not the way to go

cros13

The Leaf pack has a lot of issues compared to the i3 pack even beyond the lack of thermal management.
It's not as well sealed. The design of the pack stacks several modules on top of each other (making the thermal issues worse), older mark 1 leaf packs use practically the most temperature sensitive lithium ion chemistry around, the aluminium casing of the pack is thin and the form factor makes the pack more difficult to fit.



The i3 battery is flat, double sealed, cooled and heated, with a thicker casing and modular architecture.
There are 12 cells in each of 8 modules, each module has it's own battery management system (well technically a CSSU (cell supervision and monitoring unit) that reports to the main BMS) and can be replaced without needing to rebalance the pack.

bonky2018

@cros13

yes the i3 battery with 9 year guarantee and 30k price tag means 3,350 euros per year fuel costs if you remain below the cycle life .
Some craft might be able to get 15 years from pack making it less again

For larger boat craft doing 4 knots along Europeans canals on daily regular basis doing average of 10 miles a day where they can obtain recharges for fre or low tarrif it could possibly be cheaper than diesel solution


However for the amateur sailor that uses boat a few times a year it would probably cost ten to 100 times more than the normal diesel fuel solutions.

However some people got mega bucks and don't care how much it costs to go green but most mere mortals drop the electric solutions like a hot brick when they run the numbers per trip .

iomusicdublin

Thanks for the interesting replies

My tjalk is 62ft long and 25 tonnes, with cargo capacity of 50 tonnes.

It has a 54 ft mast, and 2000 sq ft of sails. It spends its life sailing the lakes and twice a year both canals.

I have a donor leaf 2011. It has 200lb+ torque. The battery will be left in the leaf housing and it fits in to the boat. We use 400 watt solar systems that already power everything.

In summer I can get 240 ah of charge a day which is way more that we can ever use, in winter 100ah.

We have a rib and mirror dingy that are already electrically powered.

bonky2018

@iomusicman


Sounds likes the specs are to use the boat in the river Shannon lakes the river Shannon and the royal and grand canals

Cruising in these regions seldom involves going large distances in each day so 20 miles a day would probably be the top end with five miles each day being the norm while sailing on the lakes and maybe as much as 20 miles a day on the canal in cruising mode
I am surprised that size of boat can go in the two major Irish canals .
In case some home brew guys want to copy this idea I need to state the hazards of electric power and water they don’t mix well
The basic safety rules of DC electric power with water is 12volts to 48 there exists a risk for injury or death from short circuiting the battery .
I know most people will be surprised there is risk from 12 volts but its all to do with amps
As little as 1/2 amp can kill and in the right circumstances even 12 volts is enough to supply that amp power .However the electric world rarely has issues with death and injuries with 12 volt to 48 volts but its not risk free
48 volts to 100 volts the risk increase dramatically but still many people will survive from that type of electric shock event but sometime there can be serious burns .

From 100 volts upwards to typical 400 volt pack shocks are more often lethal and severe life long dissimilating burn injuries can follow many victims for life that survive the initial electric shock event .

That risk element tends to be why there is bucket load of 48 volt sailing boat conversions on the net and less for the higher voltages

So to further the info on small sail boat conversions i supplied a few links

The sailnet link has useful numbers

https://electricyachtsocal.com/product/thoosa-9000-48v-200a-9kw-continuous-replace-20-to-30hp-diesel/

http://biankablog.blogspot.ie/2008/05/going-electric.html



http://www.sailnet.com/forums/gear-maintenance/76724-calling-all-electic-drive-boats-2.html

http://www.trojanbattery.com/pdf/ProdSpecGuide.pdf
http://www.trojanbattery.com/product/27-agm/

http://sailboatdata.com/viewrecord.asp?class_id=680

sailnet.com wrote:

(Any EDIT are not from the original quote but are extra information)
Boat, make, model, year; (EDIT 3 TONS )
Ericson 27, 1976

Info on the electric motor, controller, batteries, charging;.
SolidNav Explorer (Mars 4kw permanent magnet, brushless, Sevcon controller. Pro Charging System -quad, Kipoint 48 volt - 20 amp charger, four group 27 agm plus four group 31 agm, PakTrakr battery montor, Turnigy Watt Meter)

Costs of conversion;
$6000

Watts used at various speeds;
(I have amp readings at 48-51 volts)
20 amps - 4 knots
90 amps - 5.7 knots

Range;
I have motored for 7 hrs at 4 knots and used one battery bank
(Edit : must be the 4 pack of AGM 31 )
so I know I can do a least 56 miles.
(Edit: the figures suggest amps are more like 15 to 17 amp not 20 amps )

Prop used and ones you had to discard and how much difference it made;
Stared with the A4 prop fixed two blade 11x10 (?) switched to fixed three blade 12x10 and gained a knot of boat speed at 20 amps.

This typical 48 volt conversion is using 2 packs each are 4 of the AGM 12 volt pack in two sizes one pack is AGN 27 ( 5 hours discharge is 95 amp ) and the other pack is AGM 31 (( 5 hours discharge is 105 amp ) reference table from AGM supplied in AGM link above

The interesting numbers is to go from 4 knots to nearly six knots the amps went from 20 amps to 90amps . A increase in speed of 25% caused a massive more than quadrupling in amp power demands as the boat started to hit it maxim water line speed where power demands can grow exponentially

This typical sail boat will generally only use the engine in calm conditions and for range reasons probably keep speeds in the low 4 knots regions .

However what the numbers cant show is the same boat if there was a stiff head wind could easy at the low speeds of 4 knots incur a exponential rise in amp demands to figures like 90 amps and if it tried to go full tilt at 6 knots against a stiff head wind it might try to demand 200 amps or more from the batteries

Its these hidden numbers which can result in the batteries and engines getting cooked and melting down especially in boats because ventilation and air cooling are not very good in many boats

A AMP power demand curve for a boat like this might like going from 1 knot to 5.8 knots (Calm seas)

Knots Speed AMPs estimate VOLT 50 watts Range MAX AGM 27 100 amps
“1 .0 knot” 02 …………estimate,,,, 50V…. 100watts…………
“1 .5 knots” 03 …………estimate,,,, 50V….150 watts…………
“2.0 knots” 05 …………estimate,,,, 50V,,,, 250 watts…………
“2.5 knots” 08 …………estimate,,,, 50V…400 watts………… 12.5 hours 30 miles range
“3.0 knots” 12 …………estimate,,, 50V…600 watts…………
“3.5 knots” 15 ………..estimate,,,, 50V…. 750 watts…………
“4.0 knots” 20 amps known….. 50V…. 1000 watt………… 5 hours ….20NMiles range
“5.0 knots” 60 ………estimate,,,, 50v …. 3000 watts…………1.5 hours ….7.5NMiles
“5.5 knots” 75 ………estimate…. 50v…..3750 watts…………1.2 hour…..6.5 NMiles
“5.8 knots” 90 amps known…. 50V….4500 watts…………1 hours ….6 NMiles range

If the same boat were to go against stiff wind of 20 knots with choppy 10 foot waves you can probably double all these amp numbers on the graph and cut the range in half for the same speeds

So that would result speeds of 4 knots would have range as low as 10 miles
If the boat could do full speed and the batteries could take the abuse of 200 amps the range would be less than 3 miles

This boat would typically have 10 to 15 BHP diesel engine and the 27 boat would weight 3 tons

Now the 10 BHP 7.5kilowatt diesel engine has global efficiency of about 5% in ideal calm conditions so only 375 watts of power is moving the boat at probably 4 knots
The electric combination uses 1000 watts of power at 4 knots but probably has a 35% global efficiency meaning again some 350 watts is used to drive the boat


The sail area would probably have only 800 watts of power but global efficiency of closer to 40% might only mean some 375 watts would be driving the boat at 4 knots

As wind power on sails increases exponentially as the wind increases the sails in strong winds can have more driving force maybe 5BHP but with higher global efficiency can sometimes return better speeds in stronger winds
However head winds working against diesel engines and electric engine will exponentially slow down boats and require and demand exponentially more BHP or kilowatts to drive boats forwards

The more weight in that boat such as adding say 1 ton extra to make it weigh 4 tons instead of 3 tons will have a exponentially bad effect on power demands both in calm conditions and strong head wind conditions

Using ball park graphs like this we can estimate approximately what power a larger 60 foot 25 tons boat will demand in calm conditions

Using the half water line speed we saw this 2 ton boat 8 amps at 50 volts or 400 watts with 100 amp battery at 2.5 knots will return 30 mile range ESTIMATE
Therefore we estimate half water line speed of 60 foot boat would be 4 knots and 25 tons would require 8 times (SAFER to say 12 times ) more watts approx. or 400 x 8 = 3200 watts or abou 5BHP
Then add in extra for extra friction from much larger heavier parasitic props and shafts and 5000 watts looks more likely
That about 7 BHP
Windage on this large b0at could mean a 20 knot head wind against the boat could more than quadruple this power demand to 30 BHP or 20Kilowatts

As we said some 35% of this power demand will go to drive the boat forwards
5000 watts / 10 x 3.5 = 1750 watts net
Diesel engine is 5% global efficiency so 20 times more power so 1750 watts x 20 = 35 kilowatts or about 40 BHP to drive this boat at 4 knots

So we need in electric power at least 5 kilowatt to do 4 knots and have in reserve the ability to produce 20 kilowatts to go against head winds .With sail boats the 20 Kilowatt demand might be limited to short times like 10 minutes using sails to get close to target region
Power craft wont have that option such as exposed canal with stiff head wind then 20 kilowatts power demands would be greater a large electric car like a LEAF doing a constant 80 MPH on the motor way so range will drop a lot .Not sure the LEAF battery without serious extra cooling can take that abuse especially the 2011 early generation batteries

That’s the way the numbers look to me based on ball park numbers

There exists electric calculator programs that can supply more exact numbers


Also the 400 watt solar panel iat 12 volt will need a DC to DC inverter to give some 420 volts to give back some recharging to the LEAF battery . That converts to only 1 amp at 420 volts and with losses more like 0.5 amp

On the lakes and Canal the marinas have ESB 220 volt but often it is only 6 amp so recharging might be tad slow if the LEAF battery is totally empty

If you have the facility to keep the diesel engine as well as the LEAF it will make life more easy for if there is stiff head wind use both engines as the electric power will help keep the fuel demands down and the diesel will help the electric from demanding too many amps and making everything maybe too hot

Also you need to find out probably online how to protect from electric shocks from water short circuits and rope around prop issues stalling the electric engine and sending the amps orbital

Keep us posted if the project goes ahead

iomusicdublin

thanks

the Tjalk only needs a max speed of 4 knots on canals, all other times we can sail, up to force 7. Under sail we can reach 16-18 knots peak and we usually sail for up to 40 miles. The mast can drop in 40 seconds.

We will use the leaf housing as it exactly is in the car

air

It should be doable enough, the easiest way is probably to drive a hydraulic pump from the motor and use a hyraulic motor at the prop. This will alleviate gearing issues and make the installation more flexible and give the Leaf drivetrain a very easy time at the cost of some efficiency.
There should be a hard power limit implemented to keep everything within the limits of power output regardless of headwinds or any other external factors.
This ferry in Scotland is a diesel electric hybrid, it uses LiFe batteries:
https://en.wikipedia.org/wiki/MV_Hallaig

If you go for a Leaf conversion make sure you get an entire car so you can reinstate the full wiring loom etc, it could be very problematic to get it running otherwise.

bonky2018

There are some interesting youtube videos on electric car conversions for you to search for

One guy bought two crashed Teslas to make one good Tesla
That was night mare project as modern car electronics are not made for mere mortals to mess with but he did succeed
However I don’t think any other mere human will ever risk that idea again after seeing the mission it was to get past complicated electronic systems

The LEAF car for all I know has sensors on the wheels no wheel rotation no go . If that’s the case then its put sensors on things like prop shaft to fool the main brain or reprogram it to do without sensors .
If you try this best to get it all working onshore first before having to crawl in the bowels of the boat trying to solder things onto the set up

Also look to see if anybody like DIY electric car conversion guy has retro fitted the LEAF system onto another type of car and hopefully some DIY guy has done that
Better still see if somebody has done a LEAF system onto a boat

The big problem with any high voltage DC is its very dangerous ability to jump across large air gaps
One reason AC took over was its lack of ability to jump across large air gaps
When electric power first came out it was normally 110 volts DC and the switches to switch on and off things were huge to reduce the spark effect .
It didn’t work so good many houses burnt down when DC current got a chance to jump some gap and create a spark and the rest was simple it resulted that the house got burnt to the ground

I noticed from the link that AIR supplied for the Scottish ship
https://en.wikipedia.org/wiki/MV_Hallaig
the service section exposed a extra problem that set back the schedule and that was with experts figuring out the gremlins

wiki wrote:

Service
Hallaig was built for the service between Sconser on Skye and Raasay and commenced service on 17 October 2013.[3] The Clydebuilt Hallaig began her first sea trials on 5 August 2013, eight months after her launch, although she had moved in and out of dry dock in Greenock under her own power in July 2013. The delay in her entry to service was caused by a last minute change in fire safety regulations which required her and her sister Lochinvar to have insulation fitted extensively to exposed steel and aluminium on board. In April 2014, Hallaig temporarily relieved on the Mallaig - Armadale service after MV Coruisk was involved in an incident at Dunoon and had to have her bow extensively rebuilt.[6]

My translation of this is the god dam electric power was leaking all over the place and they had to rebuild the ship to stop this problem
Batteries in high voltage packs act like giant coils ready to throw sparks and add in water and steel and the fun can start

I would contact the Scottish boat builders to get their opinion
My quess is they forget it and will say 400 volts DC is great way to cook your toes

If it was me I would break up the LEAF pack into 48 Volt units get some cheap second hand fork lift motors of 72volt or maybe second hand 48 volt motors and gang them to drive the one prop shaft
Ok problems to recharge .Also problems to get other motors .Again problems of extra heat losses but it gets rid of the rest of the LEAF car parts from the story and at least its risk to cook the toes is lot less.
The smell of cooked toes is repugnant especially if its your toes

I seen what AC 2000 volts plus sub station did to one guy who didn’t know his onions and messed with the sub station .
He became the ultimate carbon stick when the electric power jumped across onto his metal finger ring and he then fell across the wrong parts to fall onto
Sooner you toes than mine

air

bonky2018 wrote: »

One reason AC took over was its lack of ability to jump across large air gaps

Simply not true.

bonky2018 wrote: »

My translation of this is the god dam electric power was leaking all over the place and they had to rebuild the ship to stop this problem

Nonsense, they simply had to insulate extraneous metalwork in the vicinity of the high voltage components to comply with standards.

bonky2018 wrote: »

Batteries in high voltage packs act like giant coils ready to throw sparks and add in water and steel and the fun can start

I would contact the Scottish boat builders to get their opinion
My quess is they forget it and will say 400 volts DC is great way to cook your toes

More complete and utter nonsense, I happen to follow the blog of someone who works on the ship in question and it has been pretty much faultless since it was commissioned.

bonky2018

@AIR

The original Question was has any person any experience of retro fitting a LEAF battery and transmission to large boat

Many years working on boats seeing many accident some which killed people and some that caused life long injuries all across the EU where i have done this work has tuaght me MURPY, S LAW works in spades as soon as you go onto the water with marine craft

Normal diesel engines put in Trucks can run for donkeys years and never give any trouble but the same engine in a boat is often creating issues annualy sometimes weekly often when you need the engine most

Marine insurance companies came out in big way and stopped to pay out the claims when they found out there was modifications done to the boats
Typical modifications that have killed people is removing ballast to make boats lighter and then the boats later capsize from lack of Ballast .

One large Irish pleasure boat sank unexpectanlty .
The boat maker at risk to pick up the tab had the boat raised from the sea floor.
They found a unofficial modification to the rudder system caused the boat to sink so there was no insurance payout for the boat owner .

When there is accidents in the marine world that kill or injure or create some large incident there risks to be inquiries .It can be bad for the boat builders if they had done a unofficial modification that caused the problem

These inquiries can often turn up modifications done with non experts was the fundamental reason for the accident .That risks to have a refused marine insurance claim both to the boat owner any friends family crew and any third party effected from the event

Many years ago boats would do all sorts of strange and wonderful modification

In this world the litigation doesn't make modifications done to boats using maky up equipment .

I dought there exists any body in the marine world in Ireland who would want to get involved in project where there is so little information on the hazards of what happens when a LEAF battery is put into a marine.
environment

There is no manuals no specs no formulas no International standards of safety notices on this type of product in the marine environment.

In years to come the LEAF battery makers might sell a suitable LEAF battery that comes with warranties insurance and all the rest of stuf the battery needs to safely perform in a marine environment. They probably have already a test program in place so I would expect we will see a LEAF battery powering baot some time soon

The price to replace a LEAF battery for car in the USA is some $6500 and they give you $1000 for the old battery to use for large scale wall power solutions

I am not up to date if the UK or Ireland has a LEAF battery replacement system and the costs but with VAT transport of HAZMAT if there is I would expect battery to cost north of €9000

I for one do not want to underestimate the HAZARDS that can come from having close to 400 volts DC attached to large fully charged battery with water that can enter the boat from some faulty valve or hose fitting and have to wade through that water to pump out boat knowing i might cook my toes



Also Lithium fires are real nasty events and the pictures of the TESLA which caught fire leaving a blob of molten plastic behind dont inspire me to want to be near a Lithium battery fire when things go pear shaped

If you dought me ask the RNLI they can tell you all about the multitude of rescues they have to do with pleasure boats often from something stupid like the spray from a wave entered the boat interior and hit the electrics and killed the engine

Your Friends Scottish ship Blogg would be interesting to see if there is link .
Its always interesting to see the gremlins the big ships encounter with larger electric power. A ship like that losing several months for reproofing the insulation might be enough to make the project uneconomic.The price tag for that ship at 10 million is interesting its gonna take few years to pay back that capital outlay before the potential profits come in .The energy curves of the modern battery solutions show that some time in the next ten to 20 years the magic number of 400watts for one kilo of battery will be reached and Electric solutions will dominate .Until then its risky to capital ratio for cars ships planes to go electric on large scales in this time
expersize
For me in this time marine electric projects are more of a interesting academic exercise but until all the safety bugs are ironed out i cant see myself doing any projects that exceed 48 volts anytime soon . Even with 48volts it would probably only be done with really made kits as the devil is in the details with home brew projects

Lots of sail boat use yaught tenders where they buy a 12 volt deep cycle batter with a ready made outboard that has typically 50lbs thrust .It works well but scaling up to 400 volts without the design team that LEAF has is one hell of quantum jump

I like my toes uncooked so I wont be involved with any project like that

Good luck to others that want to try that with 400 volt packs inside a steel hull floating on water

bonky2018

I looked again at converting larger electric boats to battery run solutions with view for the DIY without protection for large voltages

So far the largest I found for pleasure boats is ocean volt 57 foot 12 ton craft
They went for two of the 15 kw using 48 volt systems to power the boat using lithium power packs Valience batteries MHA not supplied but probably is 20 amp hour types as that seems to be standard in large lithium batteries .

OCEANVOLT often use power generators run from LPG or gasoline to make hybrid solutions with 300 grams of LPG making 1 kilowatt of generator power that goes direct to motor drive conserving the battery and extending range to the limits of the LPG gas bottles the boat has .

OCEANVOLT ( http://oceanvolt.com/solutions/private/monohull/)states all electric boat conversions are done at 48 Volts for passenger safety
If these experts dont exceed 48 volts and do some fairly large boats they might know what is the safe limits for boats with water ingress can be .
A 48 volt lead acid pack battery can reach nearly as high as 60 volts when fully charged and lithium 3,7 volt per cell nominal can reach 4.2volts fully charged or also about 60 volts when fully charged

From OCEANVOLTS other conversions it looks like the rule of thumb derived from conversions shows to be 30 foot boat approx 1 kilowatt will drive a 4 ton boat at 3 knots and 2 kilowatts will drive the same boat at 4 knots and 7kw will drive 4 ton boat at 7knots ( close to water line top speed of 7 to 8 knots for 30 foot boat ).
Diesel fuel ball park power formulas are minim 1 BHP for each 500lbs or ~55 BHP (~40kw)to push 25 tons which is why more than 80bhP tends to be found in 25 tons craft
The numbers suggest 25 tons needs 6 times 2 kw or 12KW gross to drive a 25 ton at 4 knots half of its water line speed which is about 1/4 to 1/3 rd the Kw power of the diesel fuel engine demands for the same work (varies according to hull shapes and power demands) .
that suggest two of the 48 volt packs with 15 kW motors would be able to push a 25 ton boat at ~ 3 to ~4 knots but for stronger head winds 3 or four packs with 3 or four 48volt 15kw motors s would be better solutions
Alternatively with 2 15KW engine solution just wait for wind to stop blowing would be cheaper solution or motor slower at ~2 knots against strong head winds .The two motors can be ganged to drive one common prop shaft for better efficiency or simply use smaller two props to keep complexity down

This link shows the various power packs for various crafts and shows ranges at full speeds are often 1/10th those of slower speeds .Also costs are supplied and are often eye watering cost even when you calculate the cost of diesel engines which are not cheap meaning many boat users still opt to buy diesel engine solutions
http://oceanvolt.com/price-examples/