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Am I crazy? (Solar Boat Project)

Please submit your opinion about this solar boat project and possible disaster.


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RobBob

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Oct 17, 2020
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8
So according to my family I'm ruining my life, I was just under the impression I got myself a boat.

Anyway, I had the clever idea to make it solar and completely electric.

Here's my plan, I've divided it into 3 stages. All the low voltage electronics will be run through POE. With POE over Cat6 it gives you 35 watts per cable, you can efficiently pick from 18v 12v or 5v and with a POE splitter you get a standard power plug with 100mb standard ethernet connection. This will let me run android tablets through the POE with wifi turned off and ethernet connection only. You can run smart TVs this way as well. All the lights and bilge pump systems will also be run through POE. Each system will have its own battery pack which I am already building and testing. With each system like the bilge pumps on independant batteries, I'll have over a day of runtime on my systems even with the main batteries drained. POE will also give me short circuit protection along with usage statistics through the smart POE switches. You can also turn off individual ports through an API so eventually I'll make touchscreen controls. My main battery pack will be at 48v since the POE switches run on 52v this will give me the best efficiency keeping everything at 48v.

STAGE 1
My goal is to have 2-3000 watts of solar along the flybridge and extended main deck covered in solar panels. The main deck I plan to embed heated floor tubing in order to test pulling off heat and using thermoelectric modules to generate additional power. For this I plan on using two 11.5kw 48v DC hydraulic motors which have very close RPM and torque curves which match the old motors. Just 1 pair of DC motors would only give me tolling speed up to 10 knots but for stage 1 that would be fine. The problem is getting the 48v capacity I need. Was looking at trying to get some old LG 48v Server backup racks. Anything I can get cheap in bulk. Weight is not an problem since I'll be removing 12,000lbs of engine from the hold.

STAGE 2
For stage two I plan on adding solar panels on top of the flybridge and enclose the entire cabin. I hope this will give me enough surface area for another 3000 watts of panels. I can hang them off the end of the boat if I need to extend my wattage. I will then add 2-3 more 48v DC motors using a T 1:1 gearbox.

STAGE 3
I plan on adding wing like masts with solar panels. These will be at least 25ft tall and can extend out almost like a wing. The goal would be to add a minimum of 8000watts and using these wings with hydraulics they can be positioned to act as basic sails.

This is going to be my full-time project starting in February when I will also be living on the boat.
Would love any help or advice.

I'm looking for any 48v DC electronics like heating elements, a dometic 24v microwave, 48v AC units... Trying to save money wherever I can. Already have spent more than I anticipated but I also guess that's par for the course of having a boat. Also any charge controllers, solar panels or batteries. Only looking for 48v completed battery packs. My goal is to try and get as close to 8000ah at 48v. I'm removing 12,000lb of engine so I need to fill that with something. Would love to get a few commercial lithium battery backup units....
 

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Congratulations on getting a boat! Your next happy day will be when you sell it. ?

What's your goal? Is it to test theories and money be damned, or are you trying to work the economics to save money? Right now there are some interesting ideas, but a boat is a money-pit to begin with and this doesn't sound economical. If you've deep pockets and it's a personal science project power to you and can't wait to see what happens next.

All the low voltage electronics will be run through POE.
Why not just use regular marine power cable, cheaper, carries more amps, tough, and good corrosion resistance?

run android tablets through the POE with wifi turned off
Unless mounted into a dashboard, they're harder to use when tethered, consider this idea fully.

pump systems will also be run through POE
Start-up amps might fry a POE cable.

Each system will have its own battery pack which I am already building and testing.
The advantage to a centralized battery is energy isn't stranded in a system not being utilized. For example, if you size your bilge pump battery for your normal daily use, then hit a log and the bilge pump starts running non-stop you could quickly exhaust that battery and be in trouble. Also more difficult/expensive to charge multiple small battery systems.

STAGE 1
My goal is to have 2-3000 watts of solar along the flybridge and extended main deck covered in solar panels.
Don't forget that 3kW of panels is not 3kW of power. See How much Solar Energy should I expect where I live?

The main deck I plan to embed heated floor tubing in order to test pulling off heat and using thermoelectric modules to generate additional power.
Could you show your math on this? Off the cuff, it seems like a bad idea both technically (floor would have to be too hot to walk on) and economically (very poor efficiencies, you wouldn't recover the system cost).

For this I plan on using two 11.5kw 48v DC hydraulic motors which have very close RPM and torque curves which match the old motors.
Take a look at the energy consumption in watt hours, I suspect you'll find a day's worth of sun is a very small operating time.
Losing all that weight below deck will make her more susceptible to flipping upside down.

STAGE 3
I plan on adding wing like masts with solar panels. These will be at least 25ft tall and can extend out almost like a wing. The goal would be to add a minimum of 8000watts and using these wings with hydraulics they can be positioned to act as basic sails.
Definitely tippy... don't forget every pound aloft is on a lever trying to flip the boat over, for every pound 6' above the waterline you need to add 3 lbs two feet below the waterline, even then the force of the wind can push you near horizontal, so you'll need some way to raise/lower the system and panels are heavy and fragile. You might want to think about putting panels off the rails instead. If you must go different and up, think about spinning cylinders as there's a theory that when spun fast enough they become invisible to wind: see https://diysolarforum.com/threads/the-magnus-effect.26/post-125.

This is going to be my full-time project starting in February when I will also be living on the boat.
Would love to see more photos and a blog of your experiences as you go.
Best of luck!
 
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So my sub batteries would have 2 functions. They would prevent large amp spikes from hitting the main batteries. Each sub system would be able to run indefinitely as long as the main batteries were good. I can run a max of 35 watts on each POE line. All my small electronics will be less than that.

The point of having each sub system on batteries is to have a minimum of 1 full day running if the main batteries die or something shorts out.

This way I can abuse the main batteries without worrying about being dead on the water. My backup generators will have enough wattage to limp home.

As for POE cables, those things will outlast marine cables. I've run POE on a harbor and some storage yards. The wires that go out on the docks and get hit regularly with water are still good and that's after 20 years. They are hard as rock but haven't cracked. Plus I don't need to run 48v anywhere, I don't need to get stepdown adapters for 12v. I can just use POE and it's VERY efficient at delivering those low voltages, plus I don't need fuses. Short circuit protection is controlled by the POE switches.

The point is to make the entire system as efficient as possible with as little voltage dropdown or stepping up as possible.

Also, if something breaks or shorts out on the main pack, I will still have lights, pumps and could even take a shower while trying to fix the problem. This is VERY important. If the main pack dies all my systems will still continue to work and gives my boat a lot of redundancy.

Going to be making a Youtube channel going over my attempted chaos.

Somebody already stole RobBob so I'm going to try and do it under RobBobYT
I'm back on the boat starting Feb.
 
Also, my goals are to have at least a place for myself that I can work on and tinker.

I'm ok with being docked for months at a time while I figure out the engines. I can work remotely and have unlimited international roaming and do IT, I can work remotely from anywhere. My eventual goal is to have this be as self-sufficient as possible. It's also why I got a heavy duty commercial vessel. The engine and electrical is beat to shit but the hull, props and mechanical is solid and in great shape.
 
Sounds like a plan.

Meanwhile you might want to power the windlass and snug up that anchor ?.
 
So according to my family I'm ruining my life, I was just under the impression I got myself a boat.

Anyway, I had the clever idea to make it solar and completely electric.

Here's my plan, I've divided it into 3 stages. All the low voltage electronics will be run through POE. With POE over Cat6 it gives you 35 watts per cable, you can efficiently pick from 18v 12v or 5v and with a POE splitter you get a standard power plug with 100mb standard ethernet connection. This will let me run android tablets through the POE with wifi turned off and ethernet connection only. You can run smart TVs this way as well. All the lights and bilge pump systems will also be run through POE. Each system will have its own battery pack which I am already building and testing. With each system like the bilge pumps on independant batteries, I'll have over a day of runtime on my systems even with the main batteries drained. POE will also give me short circuit protection along with usage statistics through the smart POE switches. You can also turn off individual ports through an API so eventually I'll make touchscreen controls. My main battery pack will be at 48v since the POE switches run on 52v this will give me the best efficiency keeping everything at 48v.

STAGE 1
My goal is to have 2-3000 watts of solar along the flybridge and extended main deck covered in solar panels. The main deck I plan to embed heated floor tubing in order to test pulling off heat and using thermoelectric modules to generate additional power. For this I plan on using two 11.5kw 48v DC hydraulic motors which have very close RPM and torque curves which match the old motors. Just 1 pair of DC motors would only give me tolling speed up to 10 knots but for stage 1 that would be fine. The problem is getting the 48v capacity I need. Was looking at trying to get some old LG 48v Server backup racks. Anything I can get cheap in bulk. Weight is not an problem since I'll be removing 12,000lbs of engine from the hold.

STAGE 2
For stage two I plan on adding solar panels on top of the flybridge and enclose the entire cabin. I hope this will give me enough surface area for another 3000 watts of panels. I can hang them off the end of the boat if I need to extend my wattage. I will then add 2-3 more 48v DC motors using a T 1:1 gearbox.

STAGE 3
I plan on adding wing like masts with solar panels. These will be at least 25ft tall and can extend out almost like a wing. The goal would be to add a minimum of 8000watts and using these wings with hydraulics they can be positioned to act as basic sails.

This is going to be my full-time project starting in February when I will also be living on the boat.
Would love any help or advice.

I'm looking for any 48v DC electronics like heating elements, a dometic 24v microwave, 48v AC units... Trying to save money wherever I can. Already have spent more than I anticipated but I also guess that's par for the course of having a boat. Also any charge controllers, solar panels or batteries. Only looking for 48v completed battery packs. My goal is to try and get as close to 8000ah at 48v. I'm removing 12,000lb of engine so I need to fill that with something. Would love to get a few commercial lithium battery backup units....
Hi there, I restore boats for a living and have been living on boats for 20 years. My goal is very similar to yours.

The problem we face is a battery bank that can accommodate what we need. Yes solar is important but we have not the luxury of real estate. By the looks of it you have probably the same amount of space that I have. That being said 6000 watt.

I have no idea where you located but in Florida we have sun, lots of it.
As soon as I find a reliable source for a optimum battery bank that I can build myself I’ll be good to go.
Everything on my boat right now it’s 12 V I have started to convert and I’m on 24 V right now that’s off lead acid. I’m now ready to step up to 48 V but I want to go all the way, I need to be able to maintain 6000 W over an eight hour. That means running all my systems at night time without using any fossil. I build most of my own stuff refrigeration air conditioning you name it I have also not found a reliable source for 48 V DC Refrigeration and air conditioning compressors. At the present time My air conditioning is 220 V I need to convert that to 48 my refrigeration is 12-24 V and that I also want to convert to 48.
All the infrastructure on my boat this already but all I need to do is plug and play I need to buy the components and install my biggest problem is a battery bank. I really would like to go with lithium ion phosphate, Eve. My understanding is that there is a 300 amp hour lithium ion phosphate available and I cannot find a reliable source
 
I'm keeping as much of the 12volt stuff as I can. I'm running it all through poe. This gives me short circuit protection and energy monitoring. I max out at 60watts but that's plenty. The issue is with the high draw stuff.

All my heating elements NEED to be 48volts to work efficently.

As for batteries. Ohh man, I'm trying to find whatever deals I can get. I'm trying to hit up some battery backup producers for datacenters to see if they have any off-spec 48v batteies that were used.

I could use your expertise. DM me if you wanna talk shop. I'm working on my boat now. Sending this from my makeshift boat WiFi. If you don't have T-Mobile business unlimited international roaming I HIGHLY recommend it. Nothing lets you travel better than free internet anywhere...
 
Hi Rob,

Your parents are right!

But that's ok, it's your life. Some wild ideas you have. Mine are different but no less wild. And I ruined my life too!

For LiFePO4 cells contact Amy Wan. She is no longer at Xuba, but you can find her here on DIY by searching, or PM me and I'll give you her direct email. She will not rip you off. Her cells are not cheap, but she won't lie to you either.

Using off spec batteries you might find would be good too until you get everything sorted out. But ultimately you'll be looking for something which isn't (another) constant headache.

How much does your T-mobile business unlimited international cost?

Rock on.

john
 
Hi Rob,

Your parents are right!

But that's ok, it's your life. Some wild ideas you have. Mine are different but no less wild. And I ruined my life too!

For LiFePO4 cells contact Amy Wan. She is no longer at Xuba, but you can find her here on DIY by searching, or PM me and I'll give you her direct email. She will not rip you off. Her cells are not cheap, but she won't lie to you either.

Using off spec batteries you might find would be good too until you get everything sorted out. But ultimately you'll be looking for something which isn't (another) constant headache.

How much does your T-mobile business unlimited international cost?

Rock on.

john
I agree with you on a makeshift solution. Boating is a very unforgiving environment. I am ready right now for my battery bank which will be stimulated by a 6000 watt solar array. The Lady Amy Wan sound like a valuable person. If you would I would appreciate her contact info as well. This is what I think would be the best battery for my needs.
 

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I agree with you on a makeshift solution. Boating is a very unforgiving environment. I am ready right now for my battery bank which will be stimulated by a 6000 watt solar array. The Lady Amy Wan sound like a valuable person. If you would I would appreciate her contact info as well. This is what I think would be the best battery for my needs.
I'll PM you her email. Click on the little envelope on the RH top of your DIY log in page.
 
RJ45 connectors are not durable in a harsh environment. Neither moisture or vibration resistant. I am not sure what "marine" wire you think doesn't last as long as cat6, but cat6 is a really bad idea, unless you buy the direct burial type, and use weatherproofed connectors. Solid conductors fail on boats because of vibration, and that problem is worse with small wire like cat6, but cat6 is available stranded. Even then, not ideal. I have had cat6 fail on my boat in 2 years, the insulation was hard and cracked as the moisture damaged it. Meanwhile, I have other wires on my boat that are 40+ years old and fine.

Most Marine electronics these days are powered by the NMEA2000 bus. That is what you should use instead of PoE. Some proprietary versions are especially durable with waterproof connectors, and the jacket holds up to water, oil, fuel, etc.

I am having a hard time to visualize these panels that you want to use as a sort of sail. You very well may compromise the stability of the boat and capsize and sink. I have watched a boat similar to yours capsize because too many people were one the flybridge, and another boat went by and the wake was too much with the weight up there. Adding a sail like apparatus seems a very bad idea. You have no keel and no ballast, so weight needs to be kept as low as possible, with the center of gravity well below the waterline.

With those issues in mind, a project like this starts with you determining how much power you need, what size motors, and how long you want to run them before stopping to recharge. You can convert the HP of your current motors into kW, Then determine how many Wh you need to run them for how long you want to, then based on your selected voltage, determine how many Ah you need. Also, how many watts of solar you need.

Usually at this point, it is determined that it isn't possible to maintain performance and have the desired runtime. So, compromise. As is, you are looking at two 11.5kW motors. I expect those are to small if you want similar performance. Even with maybe not possible amount of solar you plan, it is only half what you would need to run two 11.5kW motors that aren't big enough for your boat. So that would need to be supplemented with batteries, and you can see where the math needs to be done from here.

With that in mind, I don't want to discourage. But spend significant time planning and doing the math. There are successful electric boats out there, so it is possible. But throwing parts at it will almost surely fail. Measure twice, cut once.
 
RJ45 connectors are not durable in a harsh environment. Neither moisture or vibration resistant. I am not sure what "marine" wire you think doesn't last as long as cat6, but cat6 is a really bad idea, unless you buy the direct burial type, and use weatherproofed connectors. Solid conductors fail on boats because of vibration, and that problem is worse with small wire like cat6, but cat6 is available stranded. Even then, not ideal. I have had cat6 fail on my boat in 2 years, the insulation was hard and cracked as the moisture damaged it. Meanwhile, I have other wires on my boat that are 40+ years old and fine.

Most Marine electronics these days are powered by the NMEA2000 bus. That is what you should use instead of PoE. Some proprietary versions are especially durable with waterproof connectors, and the jacket holds up to water, oil, fuel, etc.

I am having a hard time to visualize these panels that you want to use as a sort of sail. You very well may compromise the stability of the boat and capsize and sink. I have watched a boat similar to yours capsize because too many people were one the flybridge, and another boat went by and the wake was too much with the weight up there. Adding a sail like apparatus seems a very bad idea. You have no keel and no ballast, so weight needs to be kept as low as possible, with the center of gravity well below the waterline.

With those issues in mind, a project like this starts with you determining how much power you need, what size motors, and how long you want to run them before stopping to recharge. You can convert the HP of your current motors into kW, Then determine how many Wh you need to run them for how long you want to, then based on your selected voltage, determine how many Ah you need. Also, how many watts of solar you need.

Usually at this point, it is determined that it isn't possible to maintain performance and have the desired runtime. So, compromise. As is, you are looking at two 11.5kW motors. I expect those are to small if you want similar performance. Even with maybe not possible amount of solar you plan, it is only half what you would need to run two 11.5kW motors that aren't big enough for your boat. So that would need to be supplemented with batteries, and you can see where the math needs to be done from here.

With that in mind, I don't want to discourage. But spend significant time planning and doing the math. There are successful electric boats out there, so it is possible. But throwing parts at it will almost surely fail. Measure twice, cut once.

Hey man, thanks for the advice.

For the Cat6 cable, ya, only plan on using the best outdoor burial cable with good UV ratings and reliable weatherproof connectors. I've been working with this stuff for 20 years and even have some POE stuff I did for a marina client. I've got a pretty good idea how this stuff does around salt water and sitting in the sun.


The two small 11.5kW motors I'm hoping to initially only get 10-15 knots. I also found a transfer case that I could use to stack more. Although the limit would be 4-5 for port and starboard sides.

Ideally I would like to get one of those dual voltage AC/DC 500hp industrial motors. However, the battery requirements for that are a few years off. My initial calculations for batteries I based on running my dual 11.5kW non-stop on batteries only for 8 hours. So I'm looking to have at a minimum of 184kW @48v to start off with.

As a backup I'm hoping to have propane with a dual fuel propane generator. This way I can also use the propane for the stovetop and have a dual fireplace for wood or propane as well.

Just don't see a lot of propane on boats. Any suggestions recommendations on that would really be appreciated. Right now I just have a regular gas generator.

As for using the solar as sails. This is a long ways off and I need to find efficient ways of doing this. It could be as simple as having panels along the rails and having them rotate to either be able to catch the wind from behind or let it pass through. While maybe only giving me 5-10 knots this could be very useful if my batteries die and I wanted to recharge from the props moving through the water.
 
Hey man, thanks for the advice.

For the Cat6 cable, ya, only plan on using the best outdoor burial cable with good UV ratings and reliable weatherproof connectors. I've been working with this stuff for 20 years and even have some POE stuff I did for a marina client. I've got a pretty good idea how this stuff does around salt water and sitting in the sun.


The two small 11.5kW motors I'm hoping to initially only get 10-15 knots. I also found a transfer case that I could use to stack more. Although the limit would be 4-5 for port and starboard sides.

Ideally I would like to get one of those dual voltage AC/DC 500hp industrial motors. However, the battery requirements for that are a few years off. My initial calculations for batteries I based on running my dual 11.5kW non-stop on batteries only for 8 hours. So I'm looking to have at a minimum of 184kW @48v to start off with.

As a backup I'm hoping to have propane with a dual fuel propane generator. This way I can also use the propane for the stovetop and have a dual fireplace for wood or propane as well.

Just don't see a lot of propane on boats. Any suggestions recommendations on that would really be appreciated. Right now I just have a regular gas generator.

As for using the solar as sails. This is a long ways off and I need to find efficient ways of doing this. It could be as simple as having panels along the rails and having them rotate to either be able to catch the wind from behind or let it pass through. While maybe only giving me 5-10 knots this could be very useful if my batteries die and I wanted to recharge from the props moving through the water.
The problem with propane is that it’s heavier than air. A propane leak will fill your bilge and lower compartments with gas.
 
The problem with propane is that it’s heavier than air. A propane leak will fill your bilge and lower compartments with gas.
I have enough space on the back deck under the floor for at least 6 of those propane canisters and the way I have the hookups setup for the kitchen, all the lines would be going to under the sink which also has a drain to the outside just in case of leaks...

Would that be enough?

My current fuel capacity is 4x275 gallons, if I remove one of the aft fuel tanks I should have enough space for one of the smaller commercial propane tanks. I just don't know if they are susceptible to rust or leaks?

Also, I can get detectors but if this is not common on boats, getting non-marine rated stuff outside would be a recipe for disaster which I am trying to avoid. My backup fuel can also just be diesel. I do have an old diesel generator on board that's been dead for a while. Might be worth taking the time to fix it and keep diesel as my backup fuel. The aft tanks are also pretty new.
 
2x11.5 kW motors is roughly the same as a single 30 HP engine. You will not go 10-15kts. Maybe 4 kts if I had to guess. Not knowing the size or displacement of the boat just by the pictures, it might not even do that. If you want to really move that boat, again without knowing the size or displacement, I would be looking at a pair of motors greater than 100kW.

Propane is VERY dangerous on a boat. Most boats *do* have propane for cooking, and they are installed to strict guidelines, with safety systems to cut off the supply at the tank if there is a leak. The tank itself, along with regulators and the safety solenoid valve are installed in a gas tight compartment, with a vent on the bottom to vent propane fumes overboard.

As mentioned by Alphabavo, propane is heavy, so the tiniest leak in a line and the gas sinks to the bilge, and accumulates there until there is a high enough concentration for an explosion. With the vibration of an engine, it would be impossible to prevent and control that. Just don't, unless you want to turn your boat into a bomb. A boat recently exploded in the SF Bay due to a propane leak. If you did *any* work on the propane system yourself, and even if you didn't, you would be wise to have a licensed boat gas installer have a look. A vent under the sink is not enough, and is the type of mistake that could cause a major explosion.
 
Let’s be clear about combustibles. They are all dangerous. Propane is way underrated. Operating Preasure is 11psi. If you cannot handle that please get off the boat?‍♂️
 
2x11.5 kW motors is roughly the same as a single 30 HP engine. You will not go 10-15kts. Maybe 4 kts if I had to guess. Not knowing the size or displacement of the boat just by the pictures, it might not even do that. If you want to really move that boat, again without knowing the size or displacement, I would be looking at a pair of motors greater than 100kW.

Propane is VERY dangerous on a boat. Most boats *do* have propane for cooking, and they are installed to strict guidelines, with safety systems to cut off the supply at the tank if there is a leak. The tank itself, along with regulators and the safety solenoid valve are installed in a gas tight compartment, with a vent on the bottom to vent propane fumes overboard.

As mentioned by Alphabavo, propane is heavy, so the tiniest leak in a line and the gas sinks to the bilge, and accumulates there until there is a high enough concentration for an explosion. With the vibration of an engine, it would be impossible to prevent and control that. Just don't, unless you want to turn your boat into a bomb. A boat recently exploded in the SF Bay due to a propane leak. If you did *any* work on the propane system yourself, and even if you didn't, you would be wise to have a licensed boat gas installer have a look. A vent under the sink is not enough, and is the type of mistake that could cause a major explosion.
Yea you're right I stole some numbers from a company doing electric solar conversions. I'll need 2 engines to get 10 knots and from there my numbers are actually pretty close.

They also make a perfect drop in replacement just pricey as hell. If I'm done experimenting on my own I'll buy two of these next year.
 
Let’s be clear about combustibles. They are all dangerous. Propane is way underrated. Operating Preasure is 11psi. If you cannot handle that please get off the boat?‍♂️

The issue isn't the operating pressure, it is that it is heavier than air, so it will settle, and not disperse. Being the lowest part of the boat, it will settle to the bilge, and not be detected until the bilge pump turns on. Most other combustibles don't do that. I'm not saying keep it off the boat, but you absolutely need to take precautions that you do not need to take with other fuels.
 
Yea you're right I stole some numbers from a company doing electric solar conversions. I'll need 2 engines to get 10 knots and from there my numbers are actually pretty close.

They also make a perfect drop in replacement just pricey as hell. If I'm done experimenting on my own I'll buy two of these next year.
I don't think your expectations are reasonable, but I need more information. What is the length of the boat at the waterline, the displacement (weight) of the boat, and is it a planning boat or displacement hull? You can not be successful without working with that information as a starting point.

Only looking at the pictures, I don't think 10kts is possible without 2, maybe 4, of the _big_ motor you linked to.
 
I had a 40ft boat similar to photo. Two 3208 cats. Two miles per gallon at 8kts. You have the wrong hull for electric. You need two engines for control in tight space if there's any wind.
 
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