[galstaf]

Hey folks, I searched the forums but couldn't really find anything... most people are trying to keep their HiHy RUNNING!

GOAL: TO BUILD AN ELECTRIC BOAT (with engine back up for emergencies) !

I want to create an electric yacht with gas backup. I want to harvest the gas/electric hybrid engine, rear wheel drive and batteries from a smashed/rolled write off Toyota / Lexus / Nissan hybrid SUV. I figure this system will cost similar to replacing a trashed marine diesel.

So I am dumping virtually all the systems needed for a truck ... front wheel drive train/ seats / brakes / traction control / wheels... almost everything!
I intend to add a LOT more batteries to augment the built in batteries. I want the system to run almost entirely on battery power that can be recharged with shore power when docked, or from solar/wind generators on board.
The gas engine should only kick in in an emergency situation when either the boat needs to really move fast to get out of the way of something or if all the batteries are close to depletion.


So this is where I need you techies to help me please! :thumbsup:

• What is the bare minimum of parts I need to keep from the truck to run the system if all I am interested in is keeping the drive system? ... I want the batteries, the engine system, and the rear drive unit that will feed the propeller.
  
• Can anyone recommend a parts list / schematic showing all the parts I need to harvest?
  
• Can anyone tell me what the optimal voltage to run the http://en.wikipedia.org/wiki/Lexus_Hybrid_Drive electric motors? What would be the best way to wire the truck batteries to a bank of lead acid deep cycle batteries? (The Electric boat systems I have seen so far are typically running on a 48V system (8 X 6V golf cart batteries)).
  
• Will the system typically stay on battery power if there is ample charge available in the battery banks? I don't want the gas engine to kick in except for emergency situations.
  
• Will the gas engine also make a good generator in a pinch to run other boat systems such as cabin HVAC unit / water purification / etc etc.
  
• Is there a system to replace the built in Toyota/Nissan computer and run the entire system from a laptop instead to have total control? (perhaps some sort of testing / prototype system)
  
• Any recommendations on the best way to hook up the drive shaft to a propeller? Does anyone the maximum rotation speed of the drive shaft when the engine is running at full speed.
  
• Any recommendations about what to keep of the exhaust system and how to route it?
  
• Last but not least.. what year and model of hybrid would people recommend for such a project? And does anyone want any of the left over parts?

Kind of a weird request, but hopefully I can get some wise counsel from you good folks. And I will be glad to post the results of my project when it's done... the worlds longest and wettest Toyota Highlander .

Thanks in advance!

Ric the Brit in ATL

 

[galstaf]

Updates

OK folks ... after more investigation it would seem I may made a few assumptions that are probably not correct. I would love the more seasoned hybrid veterans to possible comment.

First.. the AWD HiHy doesn't have a drive shaft, but a third electric motor to drive the back wheels. Correct?

Also, it is not really designed like a plug in hybrid, and that the battery pack is much smaller and provides only boosting. Battery only range is very small.
So what I am proposing is essentially equivalent to a "Plug in Hybrid conversion".

Question: if I cut the gasoline to the engine completely with a shut off valve, can I then force the computer to run on battery only mode indefinitely (assuming a good level of charge on the batteries)?
Apparently the motors run on a pretty high voltage.. from what I can see upwards of 500V. This is supplied thru an inverter from a somewhat lower battery output.
Does anyone know what the output voltage of the battery bank is before it runs into the inverter?
Does anyone know how to perform a Plug in Hybrid conversion or have such documentation?

Any other comments on design. The HiHy is a parallel hybrid... do you think I would be better off with a SERIAL hybrid platform (such as the Chevy Volt).

Thanks again!

Ric in ATL

 

[lawfarm]

Responses IN CAPS, BELOW.

OK folks ... after more investigation it would seem I may made a few assumptions that are probably not correct. I would love the more seasoned hybrid veterans to possible comment.

First.. the AWD HiHy doesn't have a drive shaft, but a third electric motor to drive the back wheels. Correct?

A SECOND ELECTRIC MOTOR. THERE IS ONE ELECTRIC MOTOR INTEGRATED INTO THE ENGINE/FRONT WHEEL DRIVE UNIT AND A SECOND ELECTRIC MOTOR THAT DRIVES THE REAR WHEELS. THERE IS NO DRIVESHAFT BETWEEN THE FRONT AND REAR. THE FRONT ELECTRIC MOTOR IS LINKED TO THE ENGINE AND PROVIDES BOTH POWER TO PROPEL THE VEHICLE IN ELECTRIC MODE, THE RECHARGE FEATURE WHEN DECELERATING OR USING GASOLINE POWER, AND SERVES AS THE STARTER FOR THE ENGINE. BECAUSE OF THIS, YOU WILL NEED TO RETAIN THE FRONT ELECTRIC MOTOR.

Also, it is not really designed like a plug in hybrid, and that the battery pack is much smaller and provides only boosting. Battery only range is very small.
So what I am proposing is essentially equivalent to a "Plug in Hybrid conversion".

I'M AFRAID IT'S A BIT MORE COMPLICATED THAN THAT.


Question: if I cut the gasoline to the engine completely with a shut off valve, can I then force the computer to run on battery only mode indefinitely (assuming a good level of charge on the batteries)?

NOT WITH STOCK PROGRAMMING. WITH STOCK PROGRAMMING, IT WILL KEEP TRYING TO CRANK THE ENGINE REGARDLESS OF THE LACK OF FUEL, UNTIL IT THROWS A CODE AND THEN IT WILL NOT START. IF IT CANNOT START THE ENGINE, IT WILL NOT RUN ON PURE BATTERY POWER, BUT RATHER WILL SIMPLY NOT RUN.

Apparently the motors run on a pretty high voltage.. from what I can see upwards of 500V. This is supplied thru an inverter from a somewhat lower battery output.

CORRECT.

Does anyone know what the output voltage of the battery bank is before it runs into the inverter?

SORRY, NO.

Does anyone know how to perform a Plug in Hybrid conversion or have such documentation?

THERE ARE NO CURRENTLY DOCUMENTED PLUG-IN HYBRID CONVERSIONS OF HIHYS THAT I AM AWARE OF. THERE ARE MANY SUCH CONVERSIONS OF THE TOYOTA PRIUS, AND THAT MAY BE A BETTER MODEL FOR YOU TO WORK FROM.


Any other comments on design. The HiHy is a parallel hybrid... do you think I would be better off with a SERIAL hybrid platform (such as the Chevy Volt).

I DON'T THINK THE HIHY WILL WORK WELL FOR WHAT YOU'RE CONTEMPLATING; IT IS FAR TOO RELIANT UPON GAS POWER. THE CURRENT DRAW NECESSARY TO PROPEL A BOAT OF ANY SIZE WILL LIKELY TRIGGER THE ENGINE TO RUN AT ALL TIMES. IF YOU DID IT, YOU'D NEED A STANDALONE PROGRAMMER TO RUN THE ENGINE AND HYBRID SYSTEM...WHICH WOULD BE INCREDIBLY COMPLICATED. A SERIAL HYBRID WOULD BE MUCH SIMPLER. SIMPLER YET WOULD BE TO SIMPLY BUILD AN ELECTRIC DRIVETRAIN (BATTERIES + ELECTRIC MOTOR + CONTROLLER), AND HAVE A SEPARATE, STANDALONE GASOLINE OR DIESEL DRIVEN GENERATOR/ALTERNATOR TO RECHARGE THE BATTERIES AND/OR RUN APPLIANCES. USING AND ADAPTING A CAR-BASED SYSTEM WILL BE MUCH MORE EXPENSIVE AND MUCH LESS EFFICIENT.


Thanks again!

Ric in ATL

 

[galstaf]

Thx so much, Lawfarm! Responses below:

Question: if I cut the gasoline to the engine completely with a shut off valve, can I then force the computer to run on battery only mode indefinitely (assuming a good level of charge on the batteries)?

NOT WITH STOCK PROGRAMMING. WITH STOCK PROGRAMMING, IT WILL KEEP TRYING TO CRANK THE ENGINE REGARDLESS OF THE LACK OF FUEL, UNTIL IT THROWS A CODE AND THEN IT WILL NOT START. IF IT CANNOT START THE ENGINE, IT WILL NOT RUN ON PURE BATTERY POWER, BUT RATHER WILL SIMPLY NOT RUN.

Is this the case, even if the battery power level remains completely adequate? There is no way to force the system into an EV only mode?


Does anyone know how to perform a Plug in Hybrid conversion or have such documentation?

THERE ARE NO CURRENTLY DOCUMENTED PLUG-IN HYBRID CONVERSIONS OF HIHYS THAT I AM AWARE OF. THERE ARE MANY SUCH CONVERSIONS OF THE TOYOTA PRIUS, AND THAT MAY BE A BETTER MODEL FOR YOU TO WORK FROM.

Although I intend to run the boat at typical sailing speeds (4-7 knots), I wanted the more powerful and torquey SUV drive so I could "gun it" in to avoid an incoming storm, nuclear submarine, warship, etc I thought the prius setup might be a bit gutless for that... gas consumption is less important than speed when u r in danger!
As they all use the "Hybrid Synergy Drive" setup, would a prius Plug in conversion work on the HiHy?

I DON'T THINK THE HIHY WILL WORK WELL FOR WHAT YOU'RE CONTEMPLATING; IT IS FAR TOO RELIANT UPON GAS POWER. THE CURRENT DRAW NECESSARY TO PROPEL A BOAT OF ANY SIZE WILL LIKELY TRIGGER THE ENGINE TO RUN AT ALL TIMES. IF YOU DID IT, YOU'D NEED A STANDALONE PROGRAMMER TO RUN THE ENGINE AND HYBRID SYSTEM...WHICH WOULD BE INCREDIBLY COMPLICATED. A SERIAL HYBRID WOULD BE MUCH SIMPLER. SIMPLER YET WOULD BE TO SIMPLY BUILD AN ELECTRIC DRIVETRAIN (BATTERIES + ELECTRIC MOTOR + CONTROLLER), AND HAVE A SEPARATE, STANDALONE GASOLINE OR DIESEL DRIVEN GENERATOR/ALTERNATOR TO RECHARGE THE BATTERIES AND/OR RUN APPLIANCES. USING AND ADAPTING A CAR-BASED SYSTEM WILL BE MUCH MORE EXPENSIVE AND MUCH LESS EFFICIENT.

Any recommendations for types of motors setups.. esp serial hybrid drivetrains? I want something that has been over engineered and overly tested as it seems most of these early generations of hybrids have. The gas engine should kick in ONLY in emergency situations.
I also want the boat to run whisper quiet; having been on plenty of sailing boats with archaic diesels, I want something that has some balls but will still be quiet.
I figured the integration and engineering that have gone into Toyota HSD would be a great starting point.
We plan on possibly doing eco-tours with the platform if we can get it going, so noisy smelly diesels we would like to avoid.


Thanks again for any input from anyone!

Much obliged,
Ric

 

[lawfarm]

There is a way to force an EV mode, but it is very limited in power output and speed. I would suggest that it likely would not provide sufficient power to propel a sailboat of any reasonable size. Also, the battery output is very limited, and I doubt that you could 'trick' the system into working for longer by using more batteries.

A stock Toyota Prius is rated at a combined output of 110-134hp, depending on size. For a non-planing hull such as a sailboat, it would take substantially less horsepower than that to get up to hull speed, assuming you're talking about something 40' or smaller.

I still think the easiest method would be to use a bank of lead-acid batteries and a suitably sized electric motor (30-40hp), with an analog motor speed controller...and then have a separate, diesel-electric generator with a good muffler system that doesn't directly power the electric motor but rather only charges the batteries, and can be started as needed.

Unless you put huge horsepower into the boat, you're not going to exceed the hull speed by any significant measure, anyhow. Running some rough numbers, if you have a boat with a 35' waterline, displacement hull, weight 30,000#s, it will take 70 horsepower to get you to about 9mph...and that's the hull speed. Going to 10mph requires over 100hp. Going to 15mph requires 62,114 horsepower. You're not making any fast getaways.

 

[galstaf]

There is a way to force an EV mode, but it is very limited in power output and speed. I would suggest that it likely would not provide sufficient power to propel a sailboat of any reasonable size. Also, the battery output is very limited, and I doubt that you could 'trick' the system into working for longer by using more batteries.

A stock Toyota Prius is rated at a combined output of 110-134hp, depending on size. For a non-planing hull such as a sailboat, it would take substantially less horsepower than that to get up to hull speed, assuming you're talking about something 40' or smaller.

I still think the easiest method would be to use a bank of lead-acid batteries and a suitably sized electric motor (30-40hp), with an analog motor speed controller...and then have a separate, diesel-electric generator with a good muffler system that doesn't directly power the electric motor but rather only charges the batteries, and can be started as needed.

Unless you put huge horsepower into the boat, you're not going to exceed the hull speed by any significant measure, anyhow. Running some rough numbers, if you have a boat with a 35' waterline, displacement hull, weight 30,000#s, it will take 70 horsepower to get you to about 9mph...and that's the hull speed. Going to 10mph requires over 100hp. Going to 15mph requires 62,114 horsepower. You're not making any fast getaways.

Ha! 62000 HP! I guess I need an old 747 jet engine ;-)

As you can tell.. I am still a novice with both boats and hybrid systems. I do however have an mechanical/materials engineering degree and am a quick study.
Can you refer me to where you made the HP requirements based on Hull Speed? Is there a good website for that?

So.. the basic conclusion is that there is a massively declining rate of return once hull speed is reached and anything beyond a 40 HP motor is pointless? Correct?
So I should look for a boat platform with a relatively high hull speed, say 20+ knots and work with that, right?

Thanks so much Lawfarm... it sounds like you have a bit of background in boating too!

 

[AK_Highlander]

I concour that adapting an automotive hybrid system will be much more effort&cost than just designing a boat specific system from scratch. There may be a few individual components of a automotive system you could utilize, but the automotive computer control will be very difficult/impossible to adapt. Additionally, a boat will not be able to make effective use of the regenerative braking that an automotive system does, so negates much of the benefit of an automotive hybrid system.

 

[lawfarm]

Ha! 62000 HP! I guess I need an old 747 jet engine ;-)

As you can tell.. I am still a novice with both boats and hybrid systems. I do however have an mechanical/materials engineering degree and am a quick study.
Can you refer me to where you made the HP requirements based on Hull Speed? Is there a good website for that?

So.. the basic conclusion is that there is a massively declining rate of return once hull speed is reached and anything beyond a 40 HP motor is pointless? Correct?
So I should look for a boat platform with a relatively high hull speed, say 20+ knots and work with that, right?

Thanks so much Lawfarm... it sounds like you have a bit of background in boating too!

There are a number of different websites available that give rough estimations in hull speed and power requirements. There are few generalizations that can be made, but generally, longer hulls give more speed that shorter hulls. Also, my calculations all assume monohull design. If you go to a catamaran or trimaran, you may be able to pull off slightly higher speeds (slightly).

For the vast majority of efficient hull designs for sailboats of reasonable size (around 40' or less), 40hp is about all you can realistically use. More horsepower might give you better ability to reverse course, for example, but that's about it. Unless you get into a planing hull design (like a powerboat), you're not going to get much over hull speed. And planing hulls flat suck for sailing.

Again, I think your best course is a large battery bank + alternative energy generation (solar, wind) + large DC electric motor (around 30 hp) + separate diesel/electric generator. That'd make a pretty sweet ride.

 

[Frodo65]

HSD isn't well suited to the purpose you're proposing to employ it for. The advantage gains for HSD in a car is in avoiding the poor efficiency and accell/decell losses at light loads and in stop-and-go traffic, with regeneration helps with.

Most boats won't experience much of that sort of use, and as such the complexity and weight of a battery system won't really be 'worth it' in efficiency gains. The only advantage of a hybrid system could be in packaging for a cat - the ICE in the 'center section', and small, tightly packaged electric motors in the hulls.

This lack of advantage is doubly true for a planing hull where weight is your enemy, and you're running at pretty constant, high loads. Even if you desire a 'full-displacement' hull configuration with EV-only operation up to the hull speed (8 knots or less for most hulls - might do a mite better with a cat), the complexity won't pay back in efficiency.

Engineering-wise, here are your issues:

HSD is packaged in such a way that hooking it up to a prop is nearly impossible. You could go with remote motors (like the HiHy rear unit), but MG1/MG2 will be hard to harness to propel the craft.
The duty cycle for the inverter is such that sustained high loads will likely have durability issues. All the motors are multi-phase A/C, rather than DC. This means that the inverter is a key component.
Cooling for the MG's will be problematic - bilges typically don't move near enough air to safely cool a high-duty-cycle motor. Keeping the inverter cooling system going, even with a heat exchanger will be tough. You can forget about raw water for cooling any components - all will 'melt' in a quick order, as the alloys aren't 'raw-water-friendly'.

Frankly, for boat duty, a Diesel is a far better choice - to stay 'green', sails are still number 1. A hybrid drive won't offer any advantages in boat duty, and will likely suffer significant drawbacks of weight, electrolytic stability, components not engineered for needed duty cycles, etc.