Does Anyone Know Where I Can Get a 525hp Electric Motor?

Is Ac or DC?

Do you realise what would be the current requirements of a 525HP motor at 48V?

It would be DC. Unfortunately, no I don't realize what the current requirements would be at 48V. Perhaps the Voltage could be increased. What I'm trying to understand is can an electric powerboat can be built that can go at 80mph for at least 1 hour.

The boat is roughly 10,000 pounds and 40' long. I've been told that there aren't any controllers out there that could handle this load, because the speed of the powerboat would need to be constant (full load on the controller). Moreover, that the amount of batteries that would be needed, if it could be done, would be enormous.

Think it can be done?

In rough numbers, you're looking at 8,000 amps! I expect that even if the technical aspects of delivering 8,000 A to a motor from a bank of batteries could be resolved, the weight of the batteries would far exceed 10,000 pounds. (Requiring a larger motor...requiring more batteries...)

Thanks CSM Engineer,

I've been told approximately the same thing by another engineer. If it's not too much trouble, could I have a few minutes of your time to discuss this issue by phone? If so, can you please email me (gdpanache@gmail.com), or post here, your phone number or call me at 786.227.0185. It would be greatly and sincerely appreciated.

Regards,

Greg

As mentioned, you cannot do this with a 48VDC motor, but that would not be the way to do it anyway. You would put the batteries in series to increase the voltage, then use that higher voltage at the lower amperage to run the motor.

1 HP = 746W, so 525HP x 746 = 392kW, so if you could boost it to say 500VDC (an industry standard for large motors and controllers), you would be using 392kw / 500V = 784A (in a DC world). Still a lot, but more reasonable than 8000A! In reality what most electric propulsion boats use is AC power because it is less maintenance on shipboard applications. Theoretically you could store the energy in batteries and use an inverter to produce AC power from them.

But still, the battery size / weight issue remains. Energy out = energy in, no getting around that (not counting losses of course, which makes it worse). Then in propulsion, energy required is a factor of speed, weight and drag. Weight in boats appears irrelevant at first glance, but is relative to drag (draft). So in order to hold that much energy, you have to carry more batteries, which increases your energy requirements, which increases the number of batteries needed, which increases the energy needed etc. etc. etc. It's a law of diminishing returns. This is why stored energy electric propulsion for large vehicles remains impractical.

Hi Buddy,

Yes, sounds a great project to prototype, this can be possible by using or addapting some kind of dynamo / generator drive it by some impelers located or positioned at water level or sumerged by protecting then by some rounded metalic shield shaped in front of dynamos propellers. This actually will be like a propeller which twist by water motion thruw it as the boat are motion. Technically a dynamo or two coupled within gears addapt it for such purpose. Such arrangement can supply back up power to regenerate loose due comsuption. Those will be moving as soon the boat is in motion and by the use of power regulator and diodes together with some sort of microcontrol or computerized power monitoring system were this very probably can be achieve it. Otherwise some kind of approach by wind motion fans enclosed into an screen for accidental contact will provide power back up for the batteries as well. Good luck and enjoy the sun. ( Solar Cells Too )..!

"DEAL or Not DEAL"

MC

Psss..

Gosh, I almost forgot to mention that by including an arrangement of phase up monitored banks of capacitors we can increase the power regeneration big time here. Obviously it has to be monitored by a computer or some sort of mother board electronically controled system to balance power input and demands. But, then again this is an small idea here brainstorming a little don't bring it to the bank yet. He Ha He..! But, yes, capacitors conected in parallel will kick up power increasinly. This will provide an strong power source to move that big puppy. Alrigth fellow has fun and do not forgot to 'Lock out and Tag Out' for protection. Watch out for not let water an power come in contact which can bridge a hazard path for electric power. You got a great idea now. Easy Does It..!

AllSet...!

MC

And then you could put a wind turbine on top to help the motor produce the power to move the water turbine that will aid the motor to push the wind turbine etc.....NO!That little shielded turbine will only create drag. Any power generated will be more than lost in overcoming the extra drag! I'm not saying an electric powerboat won't work because I don't know enough about modern battery technology! But I'd imagine you would want as little touching the water as possible with no shielded/unshielded water or wind turbines! Most of your power will be used in getting the thing up on the plane! Would it be an idea to split your battery bank into two! One bank with lots of umph like a car battery ( only used to start a car! After, the alternator charges and provides general electric for the car) and one bank which will provide less power but for longer (It's on the plane so there is less drag which means you could cut down on the power!) I hope my thoughts make sense! If they don't, they were for free anyway so WTH

Another needle in the balloon, is the HP required for a 10,000 lb boat to go 80 mph. A decent flat bottom drag boat needs about 400 HP to go 80 mph, that's at about 1/4 of your 10,000 lbs weight, sooo..... I would say NO , it can't be done with batteries. Why not use a gas turbine driving a generator if it has to be electric, or geared to the prop, as the unlimited hydroplanes do?

I think that we have some rather high expectations here - some forgetting of the laws of conservation of energy, and little understanding of the dynmaics of fast planing hulls.

We build fast boats - powered by conventional petrol and diesel engines - see www.explorermarine.co.uk - and as a rough guide, power required to drive a given planing boat mass is a function of the cube of the horsepower. For a given horsepower, the speed achieved is a function of the square of the mass.

If you want to examine it in more detail, search Savitsky on Google and use his equations for boat speeds and powers, but you will need to enter many data points including Longitudonal CofG and hull deadrise angle and beam if you are to get out a meaningful result.

For comparison, the world electric speed record is held - variously - over a flying mile in each direction - no more than 20 minutes between runs in the UK, or the 1kilometre run more widely used in Europe and the USA. The latter is held by Cloud Electric 1 in a very small and very light hydroplane, at 70.6 mph.

I think that two brief spurts of speed for this trial is a better target than an 80 mph in a 40 foot boat for one hour!

Good Luck

as a rough guide, power required to drive a given planing boat mass is a function of the cube of the horsepower

You were probably trying to say something less circular here. Obviously, power required cannot be a function of the cube of power. It is roughly true that within a narrow range of speeds (and once a boat is on plane) (and for a particular boat) that power required varies with the cube of speed. The planing drag curve is both fairly straight (after the hump) and also of fairly low slope. Aero drag (for a given trim angle) goes up quite closely with the square of speed, and as a result can be a large factor in a high speed boat.

For a given horsepower, the speed achieved is a function of the square of the mass.

I think you meant that the speed is an inverse function of the square of the mass. (A 200 hp 4000 lb is clearly not 4 times as fast as a 200 hp 8000 lb boat.) But in fact, the inverse is not true either. A 200 hp 4000 lb boat (like this one) is fairly is likely to do 50 mph. A 200 hp 2000 lb bass boat won't come anywhere near close to doing 200 mph -- 70 - 75 mph is typical.

But you are right about Savitsky -- even after all these years, his calculations are still used. They do not, however, address aerodynamic resistance, which can become very large at the speeds of interest to our original poster.

You're also right about shooting for times around 30 seconds rather than many minutes or an hour. Given a small enough size, and short duration, an electric boat can go substantially faster than 100 mph.

Ken,

Thank you for clarifying my rather ill defined expressions.

Yes I was inferring that for a given boat, already on the plane, the power required to increase the speed is proportional to the cube of the speed required.

And yes, for a given hull, which is required to plane, and capable of planing, the mass to power ratio is a square function - double the mass and you will need four times the power to achieve the same planing speed. treble the mass and you will need nine times the power to achieve the same planing speed.

As you say Savitsky did not look at air drag, but then in his day the speed of boats had very little to do with aerodynamic drag. As boats have become faster, it is now much more relevant, but since drag -aerodynamic or hydrodynamic - is a function of both velocity squared and the density, it is worth pointing out that density of air is (about) 1.225 kg per cubic metre whereas the density of water is ( about) 1000 kilograms per cubic metre. Hence I think we can forgive Savitsky - in the 1960's - for deciding to neglect the aero effects.

Thanks for the clarification.

Gas TURBINE (2nos) driving axial flow Pump(2 Nos) and water jet(2 Nos) throwing out of boat-- that is the best thrustor scheme possible out of commercially available hardware. Forget about Storage Batteries /Fuel Cells driving -- a 525 HP DC motor {Remember Electric Automobile?)

Now redesign your Boat with Hydrofoil/s -- make sure you have enough draft

Once you get a liftoff ,you can reduce Thrust>Axial Pump RPM> Gas Turbine Fuel burnup rate. Two independant Water-Jet thrustors make Rudder redundant.

Where is the Fire - anyway??

Something's off here. This is way above world speed record activity.

Good alrigth then, I do have another little idea here then, which it can be probably apply for such Boat . How about "The 'Ford Turbine Engine" ? which can rev up to 31,650 rpm with 470 avg. while the output shaft turns at 3000 rpm's with a torque of 760Ft. Lbs." And this is a lot of juice for the boat. Now the catch is that this one run on gas input no electrical only. Well..!

Also, there was "the experimental 'Ford Stirling External Continuos Combustible Engine' There is no combustion within the cylinder. The expansion of the fluid drives couples of pistons througth a 'SwashPlate' mechanism. After driving the pistons, the vapor is cooled." So, these two puppys can build up a lot of juice too but they won't run on 'Electrical Input' alone. That's the catch within then. Unless we came out with some kind of an steam engine and a nice power transmission that back up the power output from the steam engine farther to make this boat accelerated significantly that should take care of that issue then. Allset, you guys have fun with that project and follow your instincts 'you have the technology' Hang in There. Lock Out and Tag for Safety Always and also keep it Dry. Smarts Buddy's for real. We getting There...

Cool Stuff,

MC

You could not reasonably do this with lead acid batteries, but if you are willing to spend the money you might be able to come close with Lithium Ion. Assuming a 90% efficiency motor/controller combo (possible but expensive) you'd need about 415 kWh of batteries. Li Ion batteries can be as light as 140 Wh per kg, or 7 kg per kWh. So, you'd have about 3000 kg in batteries (6600#). 2 motors like the Tesla motors (which are 100 lb and 225 HP or so) would do -- you could figure 150 lb each, for the increase in hp. Planing drag on a hull will be about 15% of weight, so if you built a 3000 lb hull mainly of carbon fiber (maybe 30') you'd expect 1500 lb drag on this 10,000 lb boat.

1500lb x 117 fsp = 175,500 ft.lb/sec = 319 hp. Without looking it up, I'd guess that a good prop is efficient enough to put 319 hp of 525 into forward motion.

The batteries would be about $2/Wh, so about $830,000. Everything else would be cheap, by comparison. A dragster, which only needs to run for 10 seconds or so would be far cheaper.

If cost is no object, Fuel cells and capacitors for electrical power, if the 80MPH is not needed all at once, gear reduction drive/overdrive. I don't know, just talking out of my hat, but it seemed to work on nuclear powered ships.

This will be special design .48V ac motors of smaller size are used in Diesel locos .Such a large size at 48V will be resulting in large size and high ampereage.One way I feel is to increase the speed (RPM) which will bring down the size and also use a high frequency supply may be size .Its interesting

GE, Semiens, Atomic and Electrahaul make units. The best of the units are AC and are to industry standard concerning voltage. (Traction motors)

We are a dealer. Please contact with us to discuss the details. henryzhang1@hotmail.com

525HP DC motor at 48 V, you will never find such a motor,

current will be 8200Amp....it is NOT feasable at all,

suppose it is feasable, to run it from lead acid battries 80ah for 1 hour you need 200 set of 4 batteries,

forget about it....even wind turbine could not do the job, you need 400KW of energy; it means 4 or 5 wind mils 15 feet blades and 50 feet high....can you put these on your boat??

it is a dream, dont waste time by calculation

only diesel engine can give you 400Kw on a boat......

Normally these systems are driven by diesel engines of the 1220 to 3400 hp range which far exceeds the weight and displacement of the boat. But we are not talking about continuous operation here. First step would be to determine how much weight can you put in the boat without sinking it. The second step is how many kw are you going to require. Let's think two ways, hybrid and engine power. Lets get out of the 48 volt box and look at what is offered off the shelf. AC is the only way to keep the heat down. Not your typical AC but the AC used to drive variable speed motors. Frequency changed square wave power. It drives the mining trucks, boats, submarines, and trains. Find an alternator that is light weight and will sustain your 1 hour requirement. Forget the diesel and put in an all aluminum 650 hp Chevy LS 9 http://www.thetorquereport.com/2007/11/2009_chevy_corvette_zr1_62l_ls.html Gear the output at an engine speed that can be continuous for 1 hour, say half speed or 2-1. Nearly double the HP to the alternator due to the drive reduction of 2 to 1. Think out of the box gentlemen. Let's brain storm. Can't is an unknown word in engineering. If money is no object our next step is to reduce total weight of the power system.

Nearly double the HP to the alternator due to the drive reduction of 2 to 1. Think out of the box gentlemen.

I'm afraid that's a little too far outside the box. A 2:1 reduction does not double the HP; it doubles the torque, and halves the rotational speed, leaving hp untouched (aside from drive losses of 4% or so).

Like your style Randouli!

Following on from your post, for the hours operation, any ideas as to the quantity of petrol/diesel needed to run an engine like the Chevy corvette? Could an engine of this class be converted to run on a gas possibly enabling further reduction in weight? I say possibly because which weighs less, the weight of fuel and its container, eg. 200 Lt's of petrol and a tank that weighs 20kg or the equivalent set up for gas, where I'd assume the tank would weigh more due to the pressure and safety constraints?

It would be interesting to find out what the ROT is for the petrol/gas consumption! Eg. an engine uses 1Lt of petrol running at 3000rpm in first, on a flat level surface, does 2 Km. To do the same distance using the same engine converted to gas, under the same test conditions, how much gas would it use? (just so that we have all the information on the table!) And there is no wind! (just to be sure I've covered all my bases!) And assuming at the start of the test, the two setups were of identical weight!

'Out of my box Gentlemen'

Most petrol engines use on the order of .5lb/hr/hp, so a 525 hp Corvette engine would use about 260 lb per hour at full output, or about 40 gallons per hour. Hydrogen has about the same energy quantity in one kg (2.2lb) as a gallon of petrol has: so if we round petrol up to 6.6 lb/gallon, then H2 weighs about 1/3 as much for a given energy quantity. In small quantities, I'd think the weight of the high pressure insulated tank would more than cancel the fuel weight advantage. H2 liquid, although weight efficient, is not volume efficient: 2.2 lb of liquid H2 displaces about 3 2/3 gallons, so the tank needs to be bigger, as well as insulated and structurally stronger. I think with a large tank, there might be a point at which H2 is lighter, all around, but I doubt it.

Of course, running a combustion engine would be counter-productive for a one hour speed record boat: first and foremost, it would no longer qualify as an electric boat. As a hybrid, it would be horribly inefficient: hybrids improve upon normal ICE efficiency by running at their efficiency peak more of the time. (In a Prius, or other parallel hybrids, the engine runs near its peak fairly often. In a series hybrid the engine runs at its peak virtually all the time, and is shut off entirely the rest of the time.) In a constant speed vehicle, hybridization makes a net loss. (If I cruise along at a constant speed of about 70 in my avatar trike -- at the engine's efficiency peak -- I'd be better off throwing away the batteries, generator and electric motors, and loose all the weight as well as the losses in energy conversions.) It is only because the traffic duty cycle so often uses an engine at low power where the fuel required per hp can be 5 times higher (up to infinitely higher if you are sitting at a stop light with the engine idling) that the cost and complexity of hybridizing is warranted.

If the EEstor ever pans out, then our original poster would be good to go: a light, compact electric storage device -- he would not want to use 48 volts, but at 500-1000 volts, a 525 hp motor could be made lighter than the petrol equivalent: the Tesla 225 hp motor, for instance, is less than half the weight of a comparable petrol engine.

At the other end of the speed spectrum, electric boats make phenomenally good sense. It is easy to make an electric boat which will go 5 knots for many hours: quiet, clean, pleasant cruising. Cruise a couple miles out to an anchorage, break out the wine and cheese, watch the sunset... can life get much better?

Size of Alternator to supply 525HP or 421.49KW + its prime mover motor will too big and complicated.Good old diesel engine seems to be the cheapest and best suited.

While it may be possible to find such a combination, the power-to-weight ratio of the vessel once that motor and its batteries and control equipment were attached might make the prospect unattractive in comparison to a couple of dino-power outboard engines, given the speed requirements.

http://www.leisure-marine.com.au/Evinrude/250evinV6.asp

(Other outboard manufacturers are available).