Oceanvolt Hybrid Motor

[cwjohm]

44C is right about the WBB. You certainly don't want to loiter any longer than necessary when bashing into a stiff headwind, the swell, and pushing the incoming tide.

My own view is that this oversimplifies the situation. Most times I come through the WBB heading south I run into a strong SE headwind. If I point starboard I run into land. If I point Port I am virtually headed out to sea and often into more difficult conditions. As such invariably I find I am motoring a good percentage of the time until I get clear seas and winds (at least 2-3 hours and up to 6 hours if having to motor right to Mooloolaba. Further in large swells and chop bringing the boat broadside can generate significant discomfort. Granted Kator has vastly increased pointing performance but I would still think many hours of motoring would be required at times.


Further, Kator will spend a lot of time going to and fro from Boatworks and thus through the waterways on the Gold Coast where sailing is problematic. If you get caught by the tides as I was last week your journey from Peel to Boatworks can be delayed by hours, and this was being pushed by two 55Hp motors at 2200rpm. I will be very interested to see what Tony's response will be once his does this journey a couple of times against up to 2 kn currents.

[valhalla360]

Originally Posted by GaryJones

Any conversation over the success of a system has to be based on the users set of requirements. Trying to argue about a system that doesn't meet your set of requirements or fails in one area that you find important doesn't help if that user doesn't consider that particular point valid or relevant.

This would be great!!!!

This is usually my first question when these threads come up but it always gets shunted aside by the adherents.

If you read thru some of these threads, those questioning the systems typically agree that if all you need is to get in and out of port and then you are willing to live without motoring capability, a pure electric system is viable today.

If you are willing to live with significant reduction in capability at a higher cost for negligible at best fuel consumption reduction (and quite likely increased fuel consumption), it's viable today to do a hybrid system.

It's when the adherents start talking about magic electric HP, that those who understand the physics become dismissive. (example: recent comment about a 66' cat doing 8kts on 8kw which later post by someone else dropped back to 6kt and it's still not clear what the wind, current and sea state was, so it's entirely possible the speed thru the water could have been as little as 3-4kts, which is much more believable.)

[mal_l]

Originally Posted by John Holbrook

How about a hybrid? A yamaha 4JH45 with Sail drive on one side and the Ocean Volt 15kw Sail Drive on the other side.

At 2300rpm the prop on the 4JH45 absorbs 20hp / 15kw. The ocean volt 15kw prop absorbs 15kw at 2200 rpm so pretty evenly matched at that rpm level. Depending on the size of your cat one engine / motor should be able to push it along at say 6kn. You could choose depending on the level of your batteries.

At 2300rpm the Yanmar is capable of 40hp / 30kw at the crank but the prop is absorbing half of that so fitting a 100amp 48v alternator to recharge your batteries would be no issue for the Yanmar. Of course you couldn't run the Yanmar at high rpm with this alternator working or you would overload the engine.


Sent from my iPad using Cruisers Sailing Forum

This has already been done you don't have to mix n match, Graeme Hawksley of Hybrid Marine UK has a Parallel / Serial Hybrid system for Cats (or any twin engine installation). With this system you don't need a generator just one main engine is used for propulsion and/or generating power, and if all else fails (electrics or flat batteries) you still have one diesel motor directly attached to a prop, its a good system and i understand he is reasonable priced too.
The major cost of these other serial hybrid systems like ocean volt seems to be the need for an expensive DC Generator, if you go parallel hybrid the costs (and i believe) the overall efficiency is better.

http://www.hybrid-marine.co.uk/8.html

[Schooner Chandlery]

Originally Posted by mal_l

...
The major cost of these other serial hybrid systems like ocean volt seems to be the need for an expensive DC Generator, if you go parallel hybrid the costs (and i believe) the overall efficiency is better. ...l

Do you think the costs (and prices) of DC generators may come down anytime soon?

[Stumble]

Originally Posted by Schooner Chandlery

Do you think the costs (and prices) of DC generators may come down anytime soon?

I really really doubt it. DC generators are a very mature industrial of field. Short of a revolution in all Diesel engine technology I can't see where the price drop would come from.

[mal_l]

Originally Posted by Schooner Chandlery

Do you think the costs (and prices) of DC generators may come down anytime soon?

If i was going to get a DC Generator id go with 'Polar Power' very efficient and compact Alternators using Volvo motors so service parts are common, not sure on prices though, the DC Alt is the expensive part to produce but the more common hybrid becomes and the more volume they sell prices should come down, but not for a while as they are making money on the hype right now so the profit margins will be high.

[cameron82]

Could you use capacitors as a battery bank ? I have seen a couple of concepts but not to sure about it ? the logic is that they are light weight and not that expensive

[transmitterdan]

Capacitors have no where near the energy storage density of LIthium-Ion batteries. And capacitors suffer from a linear voltage discharge curve which complicates the power control circuitry. I doubt capacitors will ever be used in place of batteries for high power propulsion.

[cameron82]

Thanks Transmitterdan .

Has anyone seen the cat about to do a circumnavigation .Can't find the video on it but looks very promising

[BigBeakie]

FYI here is link to Multihull World article on the successful use of OceanVolt SD15's on the new 20m/65ft Schionnong G-Force Speciale recently launched.

To quote the builder from the article, referring to motoring on the DC genset using 8kW of power (4kW to each motor), he said:

“We motored to the Gold Coast once the wind died out, under dark rainy skies. We used 3L of fuel per hour at a steady speed of 6kts. With a full crew of nine onboard – including the directors of Southern Spars, North Sails and Everything Marine, we were happy with that.”

G-Force 2000 Speciale

[44'cruisingcat]

For what that propulsion system costs, that's not particularly impressive.

[BigBeakie]

Originally Posted by 44'cruisingcat

For what that propulsion system costs, that's not particularly impressive.

What would impress you?

How about Tony going out of Manly with batteries at 50% SOC, cruising for 3 days and 2 nights, never running the genset, and returning to Manly with batteries full? Would that impress you?

It impressed Tony, but hey, what would he know,eh?

Not a drop of diesel used, all power courtesy of solar and the OceanVolt regeneration while sailing.

[StuM]

Originally Posted by BigBeakie

FYI here is link to Multihull World article on the successful use of OceanVolt SD15's on the new 20m/65ft Schionnong G-Force Speciale recently launched.

To quote the builder from the article, referring to motoring on the DC genset using 8kW of power (4kW to each motor), he said:

“We motored to the Gold Coast once the wind died out, under dark rainy skies. We used 3L of fuel per hour at a steady speed of 6kts. With a full crew of nine onboard – including the directors of Southern Spars, North Sails and Everything Marine, we were happy with that.”

G-Force 2000 Speciale

That's about what I do cruising on one of my Yanmars.

And my boat wasn't designed and built at great expense to be "one of the lightest and fastest cruising multihulls on the water" capable of "easily achieving 25 knots under sail."

[StuM]

Originally Posted by BigBeakie

What would impress you?

How about Tony going out of Manly with batteries at 50% SOC, cruising for 3 days and 2 nights, never running the genset, and returning to Manly with batteries full? Would that impress you?

It impressed Tony, but hey, what would he know,eh?

Not a drop of diesel used, all power courtesy of solar and the OceanVolt regeneration while sailing.

With 1650W of solar power and hydro-generation on a fast sailing boat cruising day and night? I'd be distinctly UNimpressed if that didn't keep the batteries up. What has that got to do with the pros and cons of EP?

[BigBeakie]

Originally Posted by StuM

That's about what I do cruising on one of my Yanmars.

And my boat wasn't designed and built at great expense to be "one of the lightest and fastest cruising multihulls on the water" capable of "easily achieving 25 knots under sail."

And they could have directed all 8kW to one motor for the same result, but there is no need to do that because, unlike your diesels where you want to minimise use to delay maintenance tasks and costs, the electrics have virtually no maintenance for a long, long time, like 10 years or so.

And yes, performance will be better on good sailing boats with slippery hulls and reasonable displacement (Kato cruises at about 12.5 T), but that's no different than diesels either.