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Old 27-11-2016, 23:09   #421
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Re: Oceanvolt Hybrid Motor

So Big Breakie the kw is changing and 1 EV kw is now 3kw diesel and 200ah of battery storage is now the same as 2000 ah from say 10 years ago. and boats now have regen. Now I might be wrong but isn't regen about storing the energy expended when a vehicle reduces speed or when a vehicle goes down a hill. I can't see how that works for a displacement hull which is restricted by wave configuration.

When I move my 8 tonnes of sailboat 50 miles on a calm day travelling at 7 knots I use 210 kw of energy. I need 210 12v x 200 ah batteries to provide all of that energy. Even by your claims, using a 15kw electric motor, I will still need 105 batteries. That is still 4 tonnes and this increased mass will require even greater force to propel the boat.
Even if I do what you say, and draw only 90% of the energy from batteries, I still need 95 batteries and a genset whch delivers about 4 KVA and which weighs more than the batteries it replaces and consumes 1.5 litres an hour.

So to do my journey using EV, I will now have a boat weighing well over 12 tonnes, consumes more than 1/3 of the diesel I previously consumed. When I get to shore, the batteries are flat because we drained all of the available energy out of them and also used all of the energy provided by the genset while we were travelling. We now have to recharge the batteries to do the same thing the next day. Using all of the 4 kva energy of the genset and I would be surprised if that was actually possible, it will take 24 hours of charging to fully charge the batteries assuming that batteries charge in a linear process(they don't). So I have a genset running all night and day and it consumes 36 litres of diesel to do this
So I have done my journey in a boat that is 4 tonnes heavier, and equipped with a 4 kva generator running virtually all of the time and I have consumed 46 litres of diesel (18 litres more than the trip using a diesel engine) I also have on board an incredibly complex array of cabling and electronics to manage the electric motor, energy use and recharge. All this is worth many tens of thousands of dollars.

Guess what, tomorrow I have to do it again but this time I'm bashing into a 25 knot headwind that reduces my VMG to 4 knots at 3/4 to full throttle.

The next day the weather is perfect and I'm going to go sailing at 6 knots without using the motor and don't even think abut any of that crap.

Big Breakie, this is using your system. Please explain to me, where have I gone wrong? Did I not magic it enough?
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Old 27-11-2016, 23:46   #422
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Re: Oceanvolt Hybrid Motor

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where have I gone wrong?
One thing to correct would be that regeneration in sailing boats does not mean going down a hill.
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Old 28-11-2016, 00:31   #423
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Re: Oceanvolt Hybrid Motor

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One thing to correct would be that regeneration in sailing boats does not mean going down a hill.
Good one, MyOcean It's like sailing on regen is going downhill, hour after hour, and wow, even at night!
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Old 28-11-2016, 01:34   #424
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Re: Oceanvolt Hybrid Motor

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So Big Breakie the kw is changing and 1 EV kw is now 3kw diesel and 200ah of battery storage is now the same as 2000 ah from say 10 years ago. and boats now have regen. Now I might be wrong, Ya think? but isn't regen about storing the energy expended when a vehicle you mean sailboat? reduces speed or when a vehicle sailboat goes down a hill or, keeps sailing. I can't see how that works for a displacement hull which is restricted by wave configuration. whatever that means. you mean restricted to hull speed by not being able to climb over it;s , own bow wave, or by being restricted by ocean waves???

When I move my 8 tonnes of sailboat 50 miles on a calm day travelling at 7 knots I use 210 kw of energy.Calculated how? From diesel kW at the prop? Or is it from a proper analysis using a tested algorithm such as OceanVolt use? I guess that would be too much to hope for I need 210 12v x 200 ah batteries to provide all of that energy.Actually that would be more like 504kW. As in Watt hour=Ampere hour x voltage as in 210 batteries x 200Ah =42,000 Ah x 12 volts=504,000wats=504 kW. OK? Even by your claims, using a 15kw electric motor, I will still need 105 batteries. Actually no, from an actual boat with an OceanVolt SD10 (not even 15kW !) a 12.5m Lwl 3.9m Boa 7,800kg displacemet mono actually, in REALITY no less, as in from an actual boat and EP conversion, goes about 20 nm at 5.5knots using 16kW of battery juice. Ok? That is 8 x 160 Ah Super B batteries. Not 105 or anything close to it. You see what you guys do?, and why I said this anti EP stuff is just strawman fabrication? And the rest of your hyperbole is just the same nonsense That is still 4 tonnes and this increased mass will require even greater force to propel the boat.
Even if I do what you say, and draw only 90% of the energy from batteries, I still need 95 batteries and a genset whch delivers about 4 KVA and which weighs more than the batteries it replaces and consumes 1.5 litres an hour.

So to do my journey using EV, I will now have a boat weighing well over 12 tonnes, consumes more than 1/3 of the diesel I previously consumed. When I get to shore, the batteries are flat because we drained all of the available energy out of them and also used all of the energy provided by the genset while we were travelling. We now have to recharge the batteries to do the same thing the next day. Using all of the 4 kva energy of the genset and I would be surprised if that was actually possible, it will take 24 hours of charging to fully charge the batteries assuming that batteries charge in a linear process(they don't). So I have a genset running all night and day and it consumes 36 litres of diesel to do this
So I have done my journey in a boat that is 4 tonnes heavier, and equipped with a 4 kva generator running virtually all of the time and I have consumed 46 litres of diesel (18 litres more than the trip using a diesel engine) I also have on board an incredibly complex array of cabling and electronics to manage the electric motor, energy use and recharge. All this is worth many tens of thousands of dollars.

Guess what, tomorrow I have to do it again but this time I'm bashing into a 25 knot headwind that reduces my VMG to 4 knots at 3/4 to full throttle.

The next day the weather is perfect and I'm going to go sailing at 6 knots without using the motor and don't even think abut any of that crap.

Big Breakie, this is using your system. Please explain to me, where have I gone wrong? Did I not magic it enough?
I think your electric motor is missing a few windings, if you get my drift. I'm seriously wasting my time here. I'd like a reasonable discussion, but you guys are ridiculous, so I'm outta here.

Tell ya what. When you've found an OceanVolt user who is disgusted with all the problems they are having with their EP system and the performance is so crappy that they "rip it out and put diesel in", let us know, by all means. But I won't hold my breath, unless I'm in the cockpit of a diesel stink boat, that is.
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Old 28-11-2016, 02:28   #425
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Re: Oceanvolt Hybrid Motor

A 16kw motor consumes 16kw every hour. In 7 hour journey that's 112 kw. 12v 200 ah lead acid battery should only be discharged to about 60% of full charge otherwise the battery will be damaged. So each 200 ah battery can only provide 1kw of energy. you need 112 batteries. during the motoring The 4kva genset can provide at best 25 kw and so the rest must come from 90 fully charged batteries. At the end of the journey, the batteries are down to their maximum discharge level and it will still take the genset about24 hours to recharge them assuming the battereis absorb charge at the maximimum rate all of the time. So my 2 days motoring and one day sailing becomes 1 day motoring, 1day charging, 1day motoring ,one day charging, one day sailing, 5 days. I can't get to sleep on the boatbecause the genset is pounding away day and night for 2 of those days. I have to buy more diesel and i have to service the denset diesel and the electric system.
eEven lithium should only be discharged to 80% and you still need 56 of them at well over twice the price.If you used Teslas 56kw would cost much more thanAU$50,000.
After that all of the arithmetic still holds The massive weight increase, the incredibly complex cabling and management systems, the diesel consumption of the genset.

the oceanvolt regen only works when you are sailing and willtake 4 time the hours sailing to recharge the batteries and that is sailing at hull speed all of the time but with a 10% reduction in vmg. So 7 hours motoring requires 28 hours sailing at maximum speed with no motoring in or out of port.

Please publish contact details of the people who are using this system so that we can contact them personally
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Old 28-11-2016, 04:28   #426
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Re: Oceanvolt Hybrid Motor

Dlynn,

You are maybe confused about the difference between kW (killowatts) and kWh (kilowatt-hours). A 25kW generator running for 7 hours can produce 175kWh of energy. Therefore a 16kW motor powered by such a generator needs no battery at all. And lead acid batteries can discharge more than 40% without "damage".
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Old 28-11-2016, 07:27   #427
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Re: Oceanvolt Hybrid Motor

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Originally Posted by BigBeakie View Post
I'm not sure what he meant by totally non dependant either, but setting up strawmen scenarios to try & discredit EP is really silly IMO.
The batteries are to handle the 90% of motor use. A DC genset handles the other 10% of motor use, IF you cruise in an area that demands extended motoring times. Of course, you can always CHOOSE to motor for hours on end if you wish.

An earlier post made reference to a Youtube showing a young couple's conversion of there mono "UMA" to a 4.8kW electric motor, no DC genset. They bought a second hand motor and all the bits to put it all together. Not the way I would, or am, doing it with OceanVolt, but if you go to their website SailingUMA.com you'll see that they have been happily cruising up and down the US eastern seaboard, both offshore and ICW, and to the Carib for 3,000 miles on solar & regen alone recharging their batteries. They have "yet to use their electric motor for more than 30 minutes at a time..."

While I'm here, I'll point out that I have been doing some checking on a couple of things while the EP bagging has been running it's course, ofcourse.

Just a few factoids for y'all:

1. OceanVolt have over 100 installations of just their 15kW SD15 system alone, all over the world. There have been NO warranty claims to date of faulty component(s), except one bad battery.

2. I have communicated with a number of OV users and every single one is delighted with the reliability and performance. Example, In NZ, a 50' cat regularly motors into 25 knot headwinds gusting 30, on 2 meter seas with chop, at 5 to 6 knots using 5kW to each motor. No, it is not a condomaran but has hulls designed for sailing, but still......In Brittany, a fellow has cruised for 9,000 miles so far, often under adverse conditions with NO adverse effects. Loves his EP, and he is not a newbie to cruising.

3. EP systems that I'm aware of that were taken out and replaced with diesels had major system faults and/or design issues. Such as, Controllers failing repeatedly, motors chronically overheating, electronic bits under spec'd and blowing under high load. Whadayouknow, all EP systems are not the same!

4. The technology of regen is becoming a game changer. New developments gives 300% more power than previously. And previously it was pretty damn good anyway.

So wake up guys, things are changing.
I admire your persistence to find the positive aspects.
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Old 28-11-2016, 07:40   #428
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OSSA Powerlite System by Glacier Bay

....a letter I wrote quite awhile ago in the past....

Nigel Calder
Professional Boatbuilder Magazine

Dear Nigel Calder,
I've been following this diesel-electric technology development since David Tether began his work down in Solomons Island, MD,....the 'electric wheel' I think it was referred to originally. I have also followed, and participated in, some of the fairly extensive discussions that have been posted at least 4 of the boating forums.

From all of the documentation I have collocated and saved, I find your writing on the subject the most trustworthy in my opinion. I particularly value your series of articles that have appeared in Professional Boatbuilder magazine.

I just finished reading your latest article in ProBoat #142, “The Hybrid Conundrum”. I must admit that I am a little confused, and a little disappointed that this diesel-electric technology has NOT worked out to be a much more positive technology for the pleasure boater. I was sure hoping it would live up to the much vaulted hype it had originally espoused. My compliments to you for not getting trapped by the 'hype', but rather treating the subject in a very professional manner.

I do have a couple of questions for you though,...and please realize these are coming from a guy who is real 'challenged' with the subject of electrics

1) Contained in that latest article from ProBoat, you post a photo along with this description, “BluWav Systems was the most efficient large electric-propulsion motor tested by the author. The motor controller, which supplies three-phase AC power from a DC input, is at the top of the photo.” Are you saying that the AC motor(s) are the most efficient and should be utilized in these DE systems? Are you saying that DC sources (either stored and/or from a DC gen-set) are converted into AC by the motor controller to power up the AC motor??

2) Correct me where I am mistaken, but wasn't one of the real attractive features of these 'modern' DE systems the fact that simpler permanent-magnet DC motors would be utilized? ….or even a more unconventional DC motor configuration such as these recent ‘rim-drive propeller/motor combination units. I was already anticipating the development of these rim-drive propulsion units for my gamefishing catamaran design,....retractable drives as well.

3) Was my interpretation that the use of DC verse AC components in these 'modern' DE systems was advantageous such that the DC generating set could be allowed to operate at a variety of RPM's and output levels, depending upon the slow or fast speed needs of the DC motor units it was powering? In other words the DC gen-set would not have to be operated at full speed all of the time, as do the AC gen-sets need to in order to product that proper AC wave form?


My thoughts here were that the DC gen-sets would be more adaptable at supplying the propulsion motor's and/or the ship system's requirements,....and maybe even without the ship needing a big storage bank of DC power? Wasn't that the goal that Glacier Bay's OSSA system was pursuing?....a closer match between the DC power being produced vs the DC power needed at any particular time.
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Old 28-11-2016, 08:00   #429
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Re: Oceanvolt Hybrid Motor

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Originally Posted by BigBeakie View Post
I'm not sure what he meant by totally non dependant either, but setting up strawmen scenarios to try & discredit EP is really silly IMO. Unless the strawman scenarios match real life use more accurately.
The batteries are to handle the 90% of motor use. A DC genset handles the other 10% of motor use, IF you cruise in an area that demands extended motoring times. Of course, you can always CHOOSE to motor for hours on end if you wish. If you accept very limited usage at lower speeds.

An earlier post made reference to a Youtube showing a young couple's conversion of there mono "UMA" to a 4.8kW electric motor, no DC genset. They bought a second hand motor and all the bits to put it all together. Not the way I would, or am, doing it with OceanVolt, but if you go to their website SailingUMA.com you'll see that they have been happily cruising up and down the US eastern seaboard, both offshore and ICW, and to the Carib for 3,000 miles on solar & regen alone recharging their batteries. They have "yet to use their electric motor for more than 30 minutes at a time..." As has been said multiple times, if you are willing to accept drastically reduced performance, electric is viable today. A 30min cruise range is very doable even at 80-90% of hull speed. Reality is most cruisers are not purist sailors willing to drift a 2-3kts for hours on end.

While I'm here, I'll point out that I have been doing some checking on a couple of things while the EP bagging has been running it's course, ofcourse.

Just a few factoids for y'all:

1. OceanVolt have over 100 installations of just their 15kW SD15 system alone, all over the world. There have been NO warranty claims to date of faulty component(s), except one bad battery. Are they just fixing things and not calling it a warranty claim? 100 installations isn't that many.

2. I have communicated with a number of OV users and every single one is delighted with the reliability and performance. Example, In NZ, a 50' cat regularly motors into 25 knot headwinds gusting 30, on 2 meter seas with chop, at 5 to 6 knots using 5kW to each motor. No, it is not a condomaran but has hulls designed for sailing, but still......In Brittany, a fellow has cruised for 9,000 miles so far, often under adverse conditions with NO adverse effects. Loves his EP, and he is not a newbie to cruising. You sure he isn't an oceanvolt marketer? 10kW total at 6kts into a 25kt headwind on a 50' boat is patently false based on simple physics. Yes, I'm calling it a lie.

3. EP systems that I'm aware of that were taken out and replaced with diesels had major system faults and/or design issues. Such as, Controllers failing repeatedly, motors chronically overheating, electronic bits under spec'd and blowing under high load. Whadayouknow, all EP systems are not the same! Actually, the systems I'm aware of were pulled out because they couldn't perform nearly as well as claimed.

4. The technology of regen is becoming a game changer. New developments gives 300% more power than previously. And previously it was pretty damn good anyway. Regen is nice for those rare times when you are sailing long open ocean routes. Coastal cruising its far less common to get much use out of it and when anchored it generally provides nothing. For propulsion, it really doesn't add much.

So wake up guys, things are changing.
Again, when you get this boat with magical electric HP, please provide some data. If it's half as good as you claim, diesel engines will be gone within 5yrs. Of course, I'm beginning to think you are affiliated with oceanvolt as you are defending it far beyond what a casual guy interested in the tech would. Given the outright lies in some of their marketing material, I wouldn't put it past them to post under a false name.
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Old 28-11-2016, 08:16   #430
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Re: OSSA Powerlite System by Glacier Bay

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3) Was my interpretation that the use of DC verse AC components in these 'modern' DE systems was advantageous such that the DC generating set could be allowed to operate at a variety of RPM's and output levels, depending upon the slow or fast speed needs of the DC motor units it was powering? In other words the DC gen-set would not have to be operated at full speed all of the time, as do the AC gen-sets need to in order to product that proper AC wave form?


My thoughts here were that the DC gen-sets would be more adaptable at supplying the propulsion motor's and/or the ship system's requirements,....and maybe even without the ship needing a big storage bank of DC power? Wasn't that the goal that Glacier Bay's OSSA system was pursuing?....a closer match between the DC power being produced vs the DC power needed at any particular time.
Finally found an old PDF file on OSSA powerlite system
Attached Files
File Type: pdf OSSA Powerlite.pdf (19.8 KB, 43 views)
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Old 28-11-2016, 09:17   #431
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Re: OSSA Powerlite System by Glacier Bay

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....a letter I wrote quite awhile ago in the past....

Snip...
1) Contained in that latest article from ProBoat, you post a photo along with this description, “BluWav Systems was the most efficient large electric-propulsion motor tested by the author. The motor controller, which supplies three-phase AC power from a DC input, is at the top of the photo.” Are you saying that the AC motor(s) are the most efficient and should be utilized in these DE systems? Are you saying that DC sources (either stored and/or from a DC gen-set) are converted into AC by the motor controller to power up the AC motor??
For sure the most efficient system will be a 3-phase AC motor controlled by a variable speed electronic controller. These controllers can and do operate from either DC or AC. The ones that operate from DC are more efficient because to operate from AC they first have to convert AC to DC. So a DC input unit does not have the losses of converting AC to DC.

Nigel's measurements match up with theory. The idea that a DC motor is more efficient because the batteries are DC is perhaps logical but not correct.

A good 3-phase AC motor design will beat a DC motor on efficiency every time. A 3-phase motor has the advantage that its torque as a function of angular rotation is constant. In other words the magnetic field rotates and so constantly is trying to turn the armature/shaft of the motor. That means the copper wiring is smaller and wastes less heat. Also, there is not as much heat lost in the iron of the armature because the peak magnetic field is less for a given HP. It's pretty hard to beat the efficiency of an old school 3-phase motor and with modern computerized controllers it is easy to adjust speed and torque on the fly.
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Old 28-11-2016, 10:38   #432
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Re: Oceanvolt Hybrid Motor

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Dlynn,

You are maybe confused about the difference between kW (killowatts) and kWh (kilowatt-hours). A 25kW generator running for 7 hours can produce 175kWh of energy. Therefore a 16kW motor powered by such a generator needs no battery at all. And lead acid batteries can discharge more than 40% without "damage".
I see what you're doing there. Noone is talking about 25 kw generators. A16kw engine require the equivalent of 16 kw of energy to operate for one hour. If it works for 7 hours it consumes a total equivalent of 112 kw, I don't care whether it has an h on the end or not, the batteries still have to provide 112 kw of energy; all the readers know that's equivalent to 112 kw for one hour or 16 kw per hour for 7 hours. Either way your 12v batteries must provide 11,200 ah of energy to do that.
If we accept your 40% drain and at this rate, don't expect your batteries to last more than 100 charges. Even so given the energy demands on my 50 mile journey, I still end up buying and managing over 3 tonnes of batteries.
You in fact are doing just what you claimed when you say that a 16kw motor consumes 16kw when it operates for several hours The example that you give requires a 4 kw motor to drive the boat given the energy consumption (16kw over 4 hours) you are saying that my 4kw tender outboard motor can drive my 8 tonne boat at 5.5 knots. Why would I by a diesel system or an EV system if all I have to do is hook a tiny outboard motor on and away I go. $700 purchase price $20 worth of fuel to do a 50 mile journey. Even if we accept your modelling with an SD10 (10kw?) I still can do the job with an 10kw outboard ($1000). Why on earth would people put big power systems on their cruising boats when they can merrily motor along using an outboard smaller than their tender motor?
Also, the example that you give is tailored strictly for a 20 mile journey with 100% drain on the batteries. Doing that will probably blow up the batteries and the electric motor. If my actual journey is 21 miiles, my batteries go flat before I get there. Your boat can't go more than 20 miles. If I add a genset it would need to be larger than the electric engine to give it the versatillity of diesel.

Come back when you can give me contact details of actual users and can also supply me with batteries that have the same energy density as diesel oil, the same amortization costs, the same recharge rates, the same simplicity of management. Don't get me going on the cost and management of big electric motors and gensets.
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Old 28-11-2016, 11:57   #433
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Re: Oceanvolt Hybrid Motor

Dlymn,

At the risk of being accused of pedantic tendencies there is a huge difference between kW and kWh. kW is not a measure of energy, it is a measure of power. kWh is a measure of energy. They are not the same thing. One (kWh) includes the concept of time whereas power (kW) has no time reference. 1kW is 1kW whether it lasts for 1 second or one year it is still 1kW. Our arguments will be more readily understood if we use the right terminology.

I am not arguing for or against electric propulsion. I'm just trying to help everyone speak the same language.

Personally, I believe hybrid EP does not offer anything in the way of improved efficiency over diesel+mechanics. The main attraction it has is the fact that it could possibly use renewable energy (wind, solar, hydro) whilst at sea which diesel cannot. But at this time there is no suitable way to harness enough energy at sea to make a viable non-diesel cruising boat. Because of this some seem compelled to transition through hybrid diesel/electric as a stepping stone. But that is more complex than plain diesel/mechanical so they keep making up stuff to sell the unsuspecting on the concept. But that's just my opinion...
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Old 28-11-2016, 12:19   #434
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Re: Oceanvolt Hybrid Motor

Has anyone factored in using one of the new vertical mast mounted wind generators, saw one said to put out 800 watt -1KW at 18 knot wind speed.......just saying that maybe one day it will all be practical. Instead of all the negativity, maybe work toward a solution, I mean who wouldn't want to be totally independent?
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Old 28-11-2016, 12:48   #435
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Re: Oceanvolt Hybrid Motor

Lots of fud and misperceptions in this thread.

Comparing a single data point is meaningless. We need to see to power and torque curves. Until i see that data the only engineering comments i have are:

1) any comment that smells of perpetual motion is bs
2) friction is present always
3) hydrodynamic effects need to be normalized. Ie similar in terms of losses and force vectors
4) losses between rated horspower and prop torque are substantial for ic engines. So dont compare an x horsepower electric motor with an x horsepower internal combustion engine.

Can anyone post valid power and torque curves? Can anyone state the test configurations so that we can compare apples to apples?

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