Electric propulsion Repower Lagoon 560 Yanmar 110 4JH110

[LoudMusic]

I think you're overestimating your solar production on that panel arrangement. You'll likely have 1/3 shaded pretty much all the time.

I'd also consider a smaller genny that gets better sound/vibration proofing and run it all the time.

And I'd double the batteries.

But I look forward to your project's results!

[Yihang]

I would not put too much emphasis on the solar panels. With your twin 60w motors the amount of power solar generates is negligible. Just size it for your other house loads. Realistically I don't think you would want that much on the bimini, seems like a dangerous situation if you ever want to access you boom or sailbag. Not to mention windage and aesthetics.


I think this makes more sense on lightweight cats that would only require 10w oceanvolt drives. Non of the vendors really try to sell it as a solar powered system. They know an appropriate generator is needed.

https://oceanvolt.com/twin-shaftdrive-10/

https://oceanvolt.com/twin-saildrive-15/

I think at 45feet and 7.4 tons we are getting somewhere.

https://oceanvolt.com/testimonials/sy-blue-saga/

[ArranP]

Economical solution

$1,500 - Nissan Leaf Traction Motor 140 HP 110 kW, Motor Controller, Single Speed Transmission, AC-DC Inverter and Battery Charger
https://www.ebay.com/itm/Engine-EM57...5/164460522923

$500 - Control Unit for Nissan Leaf Motor
https://www.thunderstruck-ev.com/dilithium-vcu.html

$150 - Marine Throttle - Curtis ET-134
https://www.thunderstruck-ev.com/curtis-et-134.html

[zloitapok]

ArranP,
consider kW per day is wrong. Energy amount name is 'kWh'. Electric motor working at 1 kW will consume 1 kWh at 1 hour, 2 kWh at 2 hours, etc.
Solar panels at 1 kW power will produce same 1 kWh for 1 hour or 5 kWh per day, as you assume

[Yihang]

a more reasonable amount of solar panels say 5KW will get you 25kwh a day which will run one of your 110w motors at 1/4 output for an hour? That doesn't seem good. 150KWh of lithium will run one motor for an hour at full capacity.

150Kwh or lithium will be about 27 mastervolt 5500s. which cost 90kUSD and weigh about 1.6 tons or 3200LB, about 50% more than the weight of full tanks of diesel. Plus it looks like you will need a lot of diesel to run the electric motors. So you will probably need to place the 27 very large batteries somewhere else.

I think you will need to reduce the size of your motors for this to make any sense. Oceanvolt reckons 40w motor from them is about 100hp with the right prop.

[ArranP]

I use prismatic cell battery for my off-grid solar system, BMS included.

$23,700 150KW 1,320kg ( 15x $1,580 10KW LiFePO4 Lithium Li Ion 48V 200ah 88kg )

https://www.alibaba.com/product-deta...3ac82fc2PWYzqe

[ArranP]

Originally Posted by ArranP

range / recharge time - comparisons

Daily Solar collection for Lagoon 560 assumes :-

• 4 sun hours per day
• 60% of total panel rating due to shading from boom and sails

Daily Solar collection for Silent Yachts assumes :-

• 4 sun hours per day
• 100% of total panel rating as there is no boom or sails

[Yihang]

I think it's a great project but are you really attached to the Lagoon? I think it might be good to start with a lighter hull like an outremer 51, 55, Ita 14.99 or balance.

The Silent yacht 55 is about 7 tons lighter than the lagoon. ITA 14.99 has a ready to go hybrid version with oceanvolt system for 1.2 mil euros.

The Lagoon is really not the ideal platform for electric drive. You seem very technical so surely you realize this.

Might be good to sell the lagoon before all the mods, get a good price for it and hunt for a hull that is ideally suited to electric drive. Which means a big flat Bimini for solar instead of a flybridge.

[ArranP]

Originally Posted by Yihang

I think it's a great project but are you really attached to the Lagoon? I think it might be good to start with a lighter hull like an outremer 51, 55, Ita 14.99 or balance.

The Silent yacht 55 is about 7 tons lighter than the lagoon. ITA 14.99 has a ready to go hybrid version with oceanvolt system for 1.2 mil euros.

The Lagoon is really not the ideal platform for electric drive. You seem very technical so surely you realize this.

Might be good to sell the lagoon before all the mods, get a good price for it and hunt for a hull that is ideally suited to electric drive. Which means a big flat Bimini for solar instead of a flybridge.

The boat sank and has been purchased from salvage.

[Yihang]

I see. That makes more sense.

[Yihang]

Have you looked at generators? A 100KW Kohler is about 65k USD and weighs about a ton. A 110hp yanmar is less than 10k and is about 200kg.

If you just want to do it for fun then go for it but separate systems will be a pain to trouble shoot. With two yanmars you are out there before the batteries arrive from China.

Again, it's a very risky thing you are doing. The scale of the system for a lagoon 560 is a challenge.

[ArranP]

Originally Posted by Yihang

Have you looked at generators? A 100KW Kohler is about 65k USD and weighs about a ton. A 110hp yanmar is less than 10k and is about 200kg.

If you just want to do it for fun then go for it but separate systems will be a pain to trouble shoot. With two yanmars you are out there before the batteries arrive from China.

Again, it's a very risky thing you are doing. The scale of the system for a lagoon 560 is a challenge.

I've been quoted by a Yanmar dealer, $50,000 for 2x Yanmar 110, 2x ZF 68 IV Transmission and 1x Control Unit. However, the lead time is currently 6 months due to a backlog in the manufacturing of the ZF transmission.

Batteries from Delong, I ordered a 2nd house battery 3 weeks ago, it arrived about 4 days go.

As yet I am undecided, currently in the information gathering phase.

I'll summise a complete solution into a single sheet of paper, pin it to my desktop homepage or to the wall in clear line of sight. Walk past it for few days at least to allow a period of reflection.

If I proceed at least I know, the reason(s) I choose to do so.

[SalingSue]

Unless this is a YouTube channel, or fair weather close range boat, I’d stick with diesel.

[ArranP]

Boat Speed knots = The Square Root of ( Shaft Horsepower / Weight lbs ) x Constant

110 Yanmar 110 ( HP )
86,840 laden Weight ( lbs ) ( 130% of dry weight )
275 Constant ( Catamaran constant from Mercury )
--------------------------------
9.79 knots = ( ( HP / laden lbs ) ^ (1/2) ) * 275 ( excel formula )

HP / Kw at various speed knots...

knots HP kW
1 1 1
2 5 3
3 10 8
4 18 14
5 29 21
6 41 31
7 56 42
8 73 55
9 93 69
10 115 86
11 139 104
12 165 123
13 194 145
14 225 168
15 258 193
16 294 219

to achieve 9 knots 69kW are needed... 40kW will give between 6 and 7 knots.... 14 kW will give 4 knots.

[sail4evr]

Electric propulsion boats have a history of being underpowered. Finding it necessary to run generators for any extensive motoring. I would find a similar boat with electric engines and charter it for a week or two to be comfortable with your engine decisions.