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Old 06-05-2017, 07:28   #796
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Re: Oceanvolt Hybrid Motor

Quote:
Originally Posted by Seaslug Caravan View Post
Dear BB, out of interest, are you a distributer for this product.

For someone with a passing fascination you go to great efforts to defend OV.

If not then you may find that people are not attacking the concept and OV, but merely shinning a little torch light , to illuminate the "grey" areas so to speak. I think most posters here would like you to go into any purchase agreement with as much information as possible. Its the "cruisers way" to look out for each other.

Attacking the messenger is no reward for our combined efforts and concerns.
Dear Slug, no, I have no affiliation with or any relationship at all with any vendor, OV or otherwise, period. I have been interested in EP for several years and as I have learned more about it, it became something I thought MIGHT be viable for our cat, which has been a long process.

So what makes you think it was a "passing fascination"? Why did you choose those words?

I have made the determination that OV has the best EP solution available, and when people spout absolute rubbish about it, especially out of what seems like willful ignorance, I sometimes try and correct the record. Example this current regen nonsense by people who have never been on an OV boat, nor obviously made any effort to determine any facts. As I said, willful ignorance. There is nothing wrong with being ignorant, we are all profoundly ignorant about many things. One of my favourite quotes is from my University Physics professor, a double Ph.D and D.Sc. Quote "Don't be too impressed with a Ph.D. Remember a Ph.D. just serves to specify the boundaries of a persons ignorance with a bit more precision."

But willful ignorance is another matter.

As for your altruistic intentions, if you're serious, then pony up with some data, some empirical evidence, some reasoned arguement instead of conjecture and snide belittling comments about EP. That would be helpful.

What evidence do you have that OV regen has alot of drag?

Out of interest, are you a distributor for diesel engines or work for a company in the petroleum industry? For someone with no obvious interest in EP, you seem to spend alot of energy finding fault with EP.

See? Two can play that game.
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Old 06-05-2017, 07:45   #797
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Re: Oceanvolt Hybrid Motor

Oh yes"Ignorance is bliss". for someone with such a long term interest your total lack of knowledge on the specifics such as DRAG, and the fact that WORTHWHILE REGEN actually starts above typical speeds for your selection of boat is even more bewildering.



You have a great resource here on CF. Its unfortunate that the FACTS you don't like are discarded as WILFUL IGNORANCE.

All the best with your endeavours.
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Old 06-05-2017, 09:21   #798
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Re: Oceanvolt Hybrid Motor

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Originally Posted by BigBeakie View Post
Yes, that is with the old prop and it is about what Watt & Sea produces at it''s MAXIMUM. And quite a few people get those, hmmm, don't they?

And what do you know? Mr. Slug, displaying his typical tendency to confirmation bias, neglected to tell you that if you manage to squeeze just 1 more knot from your boat, what do you know, you get 1,000 watts of power just sailing along, hour after hour. So that's not useful, is it? And it just keeps going up.

But fear not, dear EP deniers. The new OV regen solution soon to be released will give you about 1,800 watts at 8 knots, 2,200 watts at 9 knots, 3,000 watts at 10 knots.

Is that useful Mr. Slug? Do you get what this is all about now, hmmm?

By the way, how fast does your boat go? What boat do you have?
In a 100% efficient system (includes prop and generator), it takes ~2.5hp to generate 1800watts, ~3hp for 2200watts, ~4hp for 3000watts. That means your sails have to produce that much extra power, deliver it through the rigging and hull, to meet the stated claims. There is no doubt engineers can design a more efficient prop and generator, but they certainly can't defy the laws of physics and produce more electricity with less than 1hp per 745.7watts.

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Originally Posted by BigBeakie View Post
Look. Don't get me wrong, I would love this all to work. At the moment it just doesn't add up.

Look, Slug, this is fascinating to me, mate. I'm a firm believer in that people of good intentions can, if not agree with each other, at least understand where the other person is coming from.

With you, and a few others that regularly dump on any aspect of EP they
can possibly find, I think maybe you just enjoy the contrarian game. I don't think you are really even trying to get at what is real about EP.

I took some time in post #783 to try and explain why there was minimal drag with the way OceanVolt do regeneration. No other EP vendor does anything similar, to my knowledge, but the point is, nobody seems to want to discuss that info in post #783 above. Did anybody else notice that??

To me that indicates what is going on here, i.e. with the exception of cwjohm and Jim Cate, there are just the same predictable persons who have not advanced this discussion, and have no intention of doing so. EP is magic, it can't work, doesn't work, contravenes the laws of physics, blablabla. Classic merchants of doubt behaviour IMO.

Since I'm a bit busy building a boat, this is becoming an exercise in WOFTAM.

If anyone is genuinely interested, fair enough, happy to discuss.
I'm not dumping on EP, I own a hybrid auto, I understand how capturing extra/wasted energy and converting it to useful power makes sense. And, yes, I do believe there is extra power in a sail boat that can be recovered. As wind speed increases and you get close to reefing the sails, I know there is power to spare, but that is also the time you are putting undue stress on the rigging. Hence, generate electric with the extra power at the expense of the rigging. Also unlike a hybrid auto, the optimization of when to capture the extra/wasted power is left to the operator (i.e., lots of room for error), vs. the computer in the hybrid auto which controls all the propulsion systems.

Then comes the ROI....how many RTW cruises would it take to pay the extra cost of the EV boat???
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Old 06-05-2017, 10:18   #799
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Re: Oceanvolt Hybrid Motor

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Originally Posted by svseachange View Post
Yeah mate. It doesnt make any sense when you boil it a down to money and sense.

There is efficiency loss running a genny to power a motor. Or to run a motor to generate electricity via water flow. That is black and white. Clear as day. Crystal clear. Etc.

But that is not really what this is all about. These guys are bleeding edge, high stakes dreamers and very wealthy guys and girls are willing to throw money at them. More power to them. Something useful might just come out if it.
Given above you can have generously sized fuel cell onboard together with EP. As a result price will go up, and efficiency will be better than with a diesel.
And you might have some trouble finding the right fuel at the gas station , but nothing to make it impossible, just expensive and inconvenient.
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Old 06-05-2017, 11:16   #800
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Re: Oceanvolt Hybrid Motor

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Originally Posted by DotDun View Post
I'm not dumping on EP, I own a hybrid auto, I understand how capturing extra/wasted energy and converting it to useful power makes sense. And, yes, I do believe there is extra power in a sail boat that can be recovered. As wind speed increases and you get close to reefing the sails, I know there is power to spare, but that is also the time you are putting undue stress on the rigging. Hence, generate electric with the extra power at the expense of the rigging. Also unlike a hybrid auto, the optimization of when to capture the extra/wasted power is left to the operator (i.e., lots of room for error), vs. the computer in the hybrid auto which controls all the propulsion systems.
Would you express the same concern if I choose to equip my boat with fixed props vs. folding props? I am guessing the drag from a fixed prop on a diesel sail drive is higher than the spinning prop on an OceanVolt.

Regards,
- Fabian
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Old 06-05-2017, 11:36   #801
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Re: Oceanvolt Hybrid Motor

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Originally Posted by fabgo View Post
Would you express the same concern if I choose to equip my boat with fixed props vs. folding props? I am guessing the drag from a fixed prop on a diesel sail drive is higher than the spinning prop on an OceanVolt.

Regards,
- Fabian
That's the point, you have to guess as no info is available on how much drag OV system produces when regenerating. No tables or graph with drag vs speed and power generation vs speed for the same prop.
If they would at least provide any info on efficiency, it would be easy to calculate, but of course they won't. All we have is some obviously false claims by overenthusiastic supporter violating the laws of physics.
Using a turbine designed for that, efficiency could easily be above 50%, but it wouldn't work as a prop with exceptional efficiency. Using a prop, the efficiency while generating, could be anything between 25% and 1%, and it makes all the difference what the real value is. You see, it's not about how efficient OV is, but how inefficient any prop is while generating that is the problem. There is nothing OV can do about it without inventing new laws of physics, and they know it.
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Old 06-05-2017, 11:49   #802
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Re: Oceanvolt Hybrid Motor

Quote:
Originally Posted by Claude-D View Post
https://youtu.be/NH5IoJIY3MM



I supplied the Oceanvolt motors (and other components) to Noosa Marine and was onboard Kato for the sea-trial. So, I am in a position to answer some of your queries and concerns.

Since the talk is very much focused on hydro-generation at the moment, let me start with this Youtube video on board Kato cruising along at 20 to 25 knots… The hydro-regeneration at these speeds was comfortably above 4-5 kW per motor (up to 9.2kW! per motor) Of course, some speed is lost to the hydro-generation. But it is very hard to guess or measure how much, and frankly - who cares! One thing is sure, it is very much “insignificant", and very much in line with what Oceanvolt claims. (Extract from Oceanvolt FAQ: “Hydro generation creates drag of only 0.1 of a knot at boat speed of 7.0 knots - barely noticeable.”)

I was amused to read some of the comments about the drag of the Hydro-generation being comparable to having a couple of 6hp motor pushing the boat in reverse. What are we talking about here? Are we saying that Kato running in 15-20 knot winds with a triple reef should be sailing at over 30 knots? And that 23 knots is not fast enough? Granted, there is to be some loss of speed, after all “nothing is lost nothing is gained” as Lavoisier was saying… but, the reality is that it is “insignificant” and that Tony on Kato or Conrad on his IMOCA 60 cannot notice or measure it, the same as other Oceanvolt customers using hydro-generation.

Another point for your consideration is that the propellor used on Kato is a stock standard three bladed Gori propeller. So, when the hydro-generation is not in use the propeller is fully closed, just like in any other motor installation. And when the hydro-generation is working the prop is only partially open. So, the hydro-generation should be seen as a bonus. One bonus that you do not have on your diesel motor. Further, you also have the option to use it only when you need too. And the drag from the Oceanvolt SD15 fitted with a Gori propeller is less than the drag of a diesel sail drive equipped with the same Gori propeller. Very much a consideration on Kato.

It is fun to think that for example on Kato at 20 knots, Tony will get more power from the hydro-generation then from his genset, with a lot less noise, vibration and fumes.

And regarding Conrad’s incredible achievement in the Vendee on his old IMOCA 60: considering his budget and the age of his boat, this is an amazing result. He leads the old boat fleet and was in front of many of the new generation boats. So, to read a comment like “yes, but did he win” is leaving me scratching my head… It is also important to note that Oceanvolt was used not only to be green but also in an effort to simplify the onboard system and to REDUCE weight, just like onboard Kato. Traditionally onboard the Vendee Globe boats, diesel gensets and inboard engines are nothing but trouble. And the weight of the fuel that you have to carry is not negligible. To illustrate this, consider that to use your genset an hour a day for 120 days (including a safety margin) you need to have maybe 400 litres of diesel on board. The weight of this fuel is more than the total Oceanvolt SD15 installation (motor, batteries, inverter, controller cables etc).

Another important point to add here is that contrary to what I have read on this forum, the fire on board Conrad’s boat had nothing to do with the Oceanvolt installation. It was the solar controller that failed in a spectacular fashion… This solar regulator was not part of the Oceanvolt installation and was one of the same used in many other solar installations. Same as you may have yourself on your diesel-powered multihull. One more thing; Conrad did lose a lot of his solar energy production, making the hydro-generation function of his Oceanvolt motor even more important. And yes the Oceanvolt handled the trip without a problem, and we can expect to see a lot more of these installations in the 2020 edition of the Vendée Globe.
1) How high revs at propshaft at full power in calm conditions and what boat speed?
2) How high revs at propshaft at 23 knots while regenerating while sailing?
3) If the latter one involves more than double revs, the blades would be practically speeking fully open. Would you agree?
4) If not, the pitch of the partially closed prop must either be substantially higher than when powering, or pitch while motoring is way too much for good efficiency. Unless you can have variable pitch for some other reason, like overdrive function of gori props. Any comments?
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Old 06-05-2017, 12:08   #803
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Re: Oceanvolt Hybrid Motor

Quote:
Originally Posted by BigBeakie View Post
Jim, Sparau;

It seems to me that when folks hear that the OV regen is very efficient and productive, i.e. that it produces alot of power without slowing the boat down MUCH, they are skeptical because they are assuming that the prop is being dragged through the water like a fixed 3 blade. I recall Jim you asked about this in the past.

But it does not work like a Watt & Sea or other EP systems that do rely on the prop turning from water pressure, in reverse in the case of other EP systems.

I tried to explain this before, obviously not very well. But I'll try again.

If you go to the Oceanvolt website and look at the regen section you will find a video of the 2 blade folder prop spinning underwater. Here is what is happening, and it is not obvious.
1. The motor is put into regen mode at the throttle control at the helm.
2. You add some throttle, and the prop spins at fairly low revs to spread the blades of the prop. You will see the rpm's and power (in watts) on the system display. At this point you will see the power output, in regen mode remember, shows a bit negative value. Why? This is the energy it is taking to spin the prop. In other words it is negative regen.
3. But then when you add just a bit more power at the throttle control, you see the revs go up dramatically and the display changes from negative regen values, to positive regen output. Why? Because now the water flow is spinning the already spinning prop much faster, and the net difference is the regen output.

So basically the regen mode spins the prop just enough to keep the prop "open" ( in the case of the 2 blade folder) so that the water now does not collapse the blades, but instead causes the prop to spin faster from water pressure on the blades. Kind of like peddling a bike and having someone running beside you pushing at the same time you are peddling. You go faster than just your peddling effort.

It is NOT like dragging a fixed 3 blade through the water, OK?

Does that help at all? All I can say is I've spoken to an engineer expert in prop design about it, and he was pretty impressed. There is some clever electronic control going on.

And when you speak to actual owners who are using these things on cruising boats, they report they do not see dramatic changes in speed as they turn regen on.... and off,.... and on,....and off. You don't think you would try it out when you got your OV system installed? Bloody oath you would. And they are not sponsored by "the vendor". Ok?
Quote:
hear that the OV regen is very efficient
No, OV is not even the point, efficiency of the prop (not made by OV, or even any prop by any design) while used as a turbine is.
Quote:
2. You add some throttle, and the prop spins at fairly low revs to spread the blades of the prop.
No, the revs must depend on both pitch and boatspeed. Any other claim is obviously false. The more pitch there is, the less revs are needed, and the more boatspeed, the more revs required. Anything else violates laws of physics.
Quote:
So basically the regen mode spins the prop just enough to keep the prop "open" ( in the case of the 2 blade folder)
No, nothing to do with keeping. Torque from the motor spin the prop at the beginning of the mode, not continuously after that like you falsely claim.

Quote:
so that the water now does not collapse the blades, but instead causes the prop to spin faster from water pressure on the blades.
The only works if the high pressure is only close to the leading edge on the forward side of the blade, not all the way and not on the rear side at all. And it requires very precise matching of revs for the prop pitch and boat speed. Too much revs and torque changes sign, working as a prop again consuming power, too little revs, and prop folds.
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Old 06-05-2017, 13:53   #804
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Re: Oceanvolt Hybrid Motor

[QUOTE=BigBeakie;2386973]

What evidence do you have that OV regen has alot of drag?

[h/QUOTE]

The evidence of logic. It takes a certain amount of power to drive a boat at a given speed. Whether the power comes from sails or motor makes no difference.

If you extract, ie remove power, it MUST result in a reduction of speed. Logic says that extracting large amounts of power will result in large reductions of speed. You can't create energy from nothing.

A practical result of this is that in hybrid and electric vehicles, regen is used for braking. Regen slows the vehicle down.
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Old 06-05-2017, 14:19   #805
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Re: Oceanvolt Hybrid Motor

Quote:
Originally Posted by fabgo View Post
I am guessing the drag from a fixed prop on a diesel sail drive is higher than the spinning prop on an OceanVolt.

Regards,
- Fabian
You may guess that, but a little study of basics physics and hydrodynamics will tell you that you are wrong.
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Old 06-05-2017, 14:26   #806
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Re: Oceanvolt Hybrid Motor

> I supplied the Oceanvolt motors (and other components)

Yep, obviously a totally unbiased report.
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Old 06-05-2017, 15:12   #807
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Re: Oceanvolt Hybrid Motor

So what have we learned over last 100 posts. The law of conservation of energy still remains inviolate (phew - what relief) but the degree of drag of OV motors on boat performance remains contentious until measured by an independent credible party. May I interrupt this pythonesque argument which will no doubt continue to make a couple of other points.

Quote:
Originally Posted by StuM
That depends entirely on your definition of "fully functional".

Which in turn depends on specified Use Cases.

If one such Use Case is the common cruiser requirement for the ability to motor in adverse condition for hours or days (in a manner similar to a standard diesel engine driven sailboat). then I dispute your assertion.
For any 45-50ft cat I would regard two 40Kw motors with a milspec 60Kw generator as fully functional, and indeed equivalent to 2 55Hp diesels. If anyone is willing to donate them to me I will pay for the installation.


[QUOTE]BB wrote:
Electric hybrid is completely viable for cruising, and may be, in fact, superior to a diesel engine system, DEPENDING on what criteria you value and DEPENDING on what type of cruising is being considered. I'm working on a white paper that examines all that we've learned, and I'll post that when it's finished. It considers cost, total cost of ownership, EP system quality & design considerations ( Serial vs Parallel, reliability, maintainability, performance in adverse conditions, and yes, limitations. There doesn't seem to be such a document or discussion that could have helped us on our journey, so I guess I'll have to do it

Just one comment on your concern about adverse conditions. What I have learned from discussions with some very experienced bluewater voyagers is the consistent message that there are ways to handle adverse wind and sea conditions besides relying on diesels to just power into it. The first rule of seamanship they stress should be "No fixed destination!-No fixed timetable!". It is also the message in Beth & Evans experience as she wrote in the great book The Voyagers Handbook, a must read. So instead of bashing into 45 knot headwinds, maybe put out a parachute and sit tight till it moderates. In other cases maybe bear off and go somewhere else.
[QUOTE]

This form of argument which may be distilled down to "There are other options so the case is not made" may be all well and good in the courts as a defence against "innocence unless absolutely proven guilty" but it becomes a bit tiresome when used day by day in statements like "There are many reasons why the atmosphere is warmed so global warming is bogus", "The bible describes another version of the history of mankind so evolution is bogus". We find similarity here, where the mere fact that there are other options to using your fixed means of propulsion, means that the fixed means of propulsion should remain unused in any situation. I do not know whether anyone sees the irony here but what this amounts to is that we would spend significant amounts of money to incorporate modern propulsion methods so that we can devolve back to the days of Sir Francis Chichester in purposefully NOT using those modern means to take the safest way out of any situation.

Indeed, one imagines a hard days sailing during a passage where winds and sea states have gradually been developing over the day and day has turned to night. Third reef has just been taken down at 35kn and 4m seas with some difficulty so much so that the fit and strong third hand hired especially for the passage sprained his wrist in the effort. The wife is in the head throwing up in a bout of extreme seasickness. I can then imagine in my minds eye BB piping up like Lord Nelson and quoting from Beth and Evans - The Voyagers Handbook "well chaps now is not the time to consider pressing a button and utilising our new fangled modern propulsion - our job is to latch on and venture into the dark and waves and combat Neptune himself by setting a parachute from the bow. I feel confident that once he has been told in no uncertain terms where he can shove his parachute that he may have cause to reconsider his position.

Rob, you state that you are a cruiser, and you may not be as ancient as myself who is in his sixties, but you are no spring chicken. It seems to me that the first rule of sailing is to take a long hard look at your reasonable capabilities in any given situation. Unless you are an experienced sailor with decades of experience or a super athlete like Bear Grills with a finely honed survival experience it behoves you to take a bells and braces approach to all facets of cruising and in my view that applies to the most reasonable availability of propulsion for all situations you may reasonably find. Indeed, in learning I sailed with experts who has hundreds of thousands of nautical miles under their belts, and the same strong message was oft repeated "Remember, we are cruisers, so when in doubt get those motors on, and ensure the boat is under control".

Leaving, all of this aside, you may well find some degree of frustration with EP in the most mundane of situations. For instance, there is no way you could get into a berth at Mooloolaba marina out of slack tide due to its cross currents, as you need to power the boat in and then slow it up quickly this requiring maximal torque. At Boatworks I found my boat put in a long back finger with clearance to other boats on 1m front and back and I had to get out of there and avoid all the other boats parked in the bays in front. To do this required maximum torque on the motors. Now you will say that patience is the key - just wait for slack tide or just wait for the other boats to go, but you will find that over time the restrictions of less torque will wear you down, as it has done in others who have given up EP for diesels.

So I remain resolute in my view. EP is viable IF an equivalent amount of torque is provided to that of diesel. To do otherwise is simply unsafe. Unfortunately, this requires significant expense, an expense that only the very wealthy can afford.

As to your white paper, this subject may not be in written form but it has been rehashed time and again in these forums and between yacht owners. The argument for TCO cannot be made, as the savings between fuel usage for a generator to drive EP and diesels is no where near enough to justify the initial cost.

There are many good reasons why someone would install EP. Financial justification is not one of them. Why don't you just admit this and stop tilting at windmills.
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Old 06-05-2017, 15:41   #808
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Re: Oceanvolt Hybrid Motor

I challenge any of you to prove there is a significant reduction in speed on any boat you choose that has an Oceanvolt SD15. Any boat at all. I am challenging you to prove your assertions with empirical evidence, instead of just flapping your gums.

YOU define what is significant, if you like. Obviously it will be more than a few tenths of a knot because it has already been acknowledged and stated by those who have been on OV boats and directly observed the regen, that there is speed reduction to this magnitude.

So would you agree on 10% of boatspeed?

If it slows an 8 knot boat by 0.8 of a knot, I will concede defeat.

Because if it is any less than that WHO CARES! Oh, that's too much? Ok let's make it 5%, so that would be 0.4 of a knot. Whatever.

So put up or shut up, as they say. Prove your case with demonstable evidence, and I will be the absolute first to thank you. But I won't be holding my breath, because it is transparently obvious the agenda that is running here.It is always the same old gum flappers that pipe up on any EP thread. It is completely obvious. The CF members previously noted excepted, because they have demonstrated a consistent positive contribution in the spirit of offering well meaning opinions and advice. I certainly do value that, and it is the power of CF. You other guys is why people avoid contributing, which I have been told directly.

I predict there will just be a continuation of flapping gums, because your real agenda is not determining anything factual about EP, it is an agenda to discredit EP in general, and in this case OceanVolt in particular.

IMHO, You are behaving EXACTLY like the climate deniers that are co-ordinated by the Heartland Institute denial campaigns, i.e. the merchants of doubt tactics. Sadly, those tactics work, as we have seen in the tobacco "debate", the climate "debate", and as employed by the Russians to discredit and raise doubt in several political campaigns, think USA and France.

The only antidote to misinformation is...EVIDENCE. Show us your evidence, we can show you the evidence for EP, now you show us your evidence to support your assertions. In this case, the EVIDENCE that OceanVolt regeneration creates enough drag to slow a boat beyond a few tenths of a knot.
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Old 06-05-2017, 15:45   #809
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Re: Oceanvolt Hybrid Motor

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Originally Posted by Just Another Sa View Post
1) How high revs at propshaft at full power in calm conditions and what boat speed?
2) How high revs at propshaft at 23 knots while regenerating while sailing?
3) If the latter one involves more than double revs, the blades would be practically speeking fully open. Would you agree?
4) If not, the pitch of the partially closed prop must either be substantially higher than when powering, or pitch while motoring is way too much for good efficiency. Unless you can have variable pitch for some other reason, like overdrive function of gori props. Any comments?
1) 2250 RPM
2) 1800-1900 RPM You can see this on my Youtube video.
3) No
4) The first propellers fitted to Kato were the three bladed Gori 16.5" X 11" We got a maximum speed of 9.3 Knots. But power used at maximum RPM (2250) was only 10kW per motor. This was an indication that the propellers could use a bit more pitch. So we swapped the propellor for 16.5" X 13" This increased our max speed by a solid one knot at 8.4kW total output (This is the genset output) and also gave us a greater top speed (10 knots) at 2250RPM and the maximum power output of 15kW per motor.
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Old 06-05-2017, 15:49   #810
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Re: Oceanvolt Hybrid Motor

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Originally Posted by StuM View Post
> I supplied the Oceanvolt motors (and other components)

Yep, obviously a totally unbiased report.

Obviously, I am biased... You point is?


You may have a right to your own opinion, but not to your own facts!
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