Hybrid sailing trimaran with electric outboard and regenerative capability

[powerabout]

I am interested to hear about the Gunboat that cat sailor mentions had a blackout in the gulf stream late last year
anyone?

 

[sparky_wap]

Go pure battery...

The A123 prismatic cells are now becoming more available. For they run about $32 US and have a 20 AH rating. For the weight of the two optimas, you can run about 400 AH @12v and use almost 100% Discharge. They are 0.5 Kg each and 80 cells would give you about 4.5kWh usuable energy. The cost would be around $2500 US and figure another $1500 for a battery management system, wiring, charger and seaworthy enclosure. The whole system would weight less than 75kg.

You could even configure the cells for 48 volts (100 AH)for an electric outboard and run an dc-dc converter for the mixer and house loads. If you need more energy, put more cells in parallel.


I recently converter my push mower to electric with these cells and can cut my whole lawn (1 hour)and have juice left. Trust me, push mowers when you cut hilly terrain are as sensitive to weight as boats.

Automotive rear axles which most are hypoids are about 92-95% efficient and it depends on load. I got that from a drivetrain engineer at Ford. I doubt the right angle drives in outboards are much different. Back driving might be a different story.

 

[blisspacket]

The term "Hybrid" evokes the efficiencies of Prius and Honda and Hyandai, where inertia is readily converted to energy when you're bringing 2500 lbs to a halt at the stoplight ahead.

Boats in water don't have a surplus inertia to create reserve energy . Even going down a long swell a hull is pushing aside masses of water. Yes there's surplus momentum to be tapped, regenerated, but the returns on investment when pushing in viscous water are nowhere as rewarding as the "Hybrids" we enjoy on land.

Asking a propeller to provide thrust up a swell and then asking that same prop to provide drive to a motor-generator going down the next swell is a different mix than the Hybrid car engineers get to play with.

Asking a propeller to drive a motor-generator while the boat is driven under sail is a worthwhile consideration. The merits of that exercise have to be scrutinized diligently: there are plenty of vendors who'll invite you to invest in batteries and motorgenerators and controllers.

Torqeedo outboards are intelligent, quiet alternatives for outboard power. For inshore-offshore power, it's hard to beat diesel power.

Boats

 

[powerabout]

I believe the Gunboats computer lowers a drive when it knows it is sailing fast enough to generate power?

 

[blisspacket]

emf and ergs and joules...

I have less than 5 miles on the water with Nissan Leaf modules; about 30 hours in the shop. I'm a tyro. But I am impressed with the stamina and the good behavior of the Leaf modules---AND their availability from wrecking yards and eBay. Too many details to cover here; if you're into battery power, the Leaf modules warrant your attention.

 

[UNCIVILIZED]

Not trying to be a wet blanket, but the following is just a reality check based on my experiences. If you do figure out a viable setup, I'd surely be curious to know about it.
Warm beer sucks! Though room temp. lemonade or lime juice, mixed with rum's fairly tolerable ;-)

One thing to think on is that if you're trying to use the hardware from the propulsion setup to generate electricity, it's going to be massively overbuilt for the task. And getting all of the weight of a shaft & gearing designed to handle horse power by the dozen up to speed, may eat up most of what a spinning prop designed for propulsion will generate. By comparison, a towed prop, trailed from a piece of spectra has a miniscule inertia moment.

On racing boats, it's common practice to lock the propeller in place so that it's vertical, and behind the strut or keel, in order to minimize it's drag. And thinking on it, it rarely takes much force to stop it from spinning, in order to get it lined up right, prior to locking it off. Nothing more than a gloved hand or boot can't handle. This is with the engine in neutral mind you.

It used to be a lot more common than now, to have a dedicated propeller on some cruising mono's, hooked up directly to stand alone generating systems. But I think that as other methods of generating electricity have become more efficient, those kinds of setups have to a large degree fallen by the wayside.
Though recently I did see a lowerable power generating system which looked kind of like a trolling motor on an ORMA 60, Mirabaud perhaps. If I run across it, I'll post it up.
But I think that for the last couple of decades, towable props attached to dedicated generators have ruled the roost. Along with solar & wind that is.

When I lived on the hook several years back, a 2sqft solar panel put out enough juice to let me watch 2 hours of TV a day, & read all night if I so chose. Ditto on the stereo time. And I only put up my old Redwing (wind generator) about once a week in the winter, when there was less sun.
Running it much more than that, & I had more juice than I could use. And this was pre LED lighting, & computer optimized battery charging regulators.

 

[Yobarnacle]

I like dedicated systems. less efficient, but redundant. And often very inexpensive. Example: intead of running lights off house battery, just buy a string of solar powered garden lights and install them where you like.. Includes the solar panel. About $10.
Bilge pump? Buy a solar powered fountain pump. Includes solar panel. about $10.
Ventilation? Buy the self-contained solar powered dome vents with the fan inside and solar panel on top.
https://www.youtube.com/watch?v=9C5H2gacSLM
About $100 to $150.

There are car window fans, solar powered, around $10. might adapt to boat.

 

[UNCIVILIZED]

CORRECTION: I found the unit of which I spoke, and it turns out that it is on the boat S/V Mirabaud, amongst others in that class. And when I went to do a search online for pictures of it, I did run across some rather interesting information. Not all of which I've had a chance to look at as yet. But here are a couple of places to start (your research) if you care to do so.
And it appears that there's a company marketing 2 separate models of hydro power generators; one for racers, & the other for cruisers.
http://www.bing.com/search?q=Mirabaud+hydro+power+generator&go=Submit+Query&qs=ds&form=QBLH
http://www.wattandsea.com/en

The catch(es) are of course the usual ones, like how long will the company stay in business. As the maritime market is a tough one to make a profit in, given that the operating environment's so hard on gear. And of course, all of the other usual ones.
Not trying to be a cynic, or an ***. It's just that I've (sadly) seen some GREAT gear, come & go in relatively short order. Due to the above. Including some I'd planned on buying.

 

[yves]

Hello there,
Bringing this thread up as I have the same idea ...
(electric outboard with hydro generation capability for a small trimaran, dragonfly 28 or 32 type)
Since the time of the thread Torqeedo now have the cruise 4.0 and 10.0 outboards, and they mention hydrogeneration capability for their pod cruise versions (but without production data).
Anybody knows whether their "big" outboards also have hydro-generation capability ?

 

[popobowa]

to genrrate power from PM brushless motor one probably has to modify/change the controller. I believe it must be possible to make a dual purpose controller too. If its a brushed PM motor it would work both ways.... like a bicycle dynamo of old.
The problem is that a propulsion prop will give you only a small yield compared to the created thrust at same speed. Max 1/3 , or app 10%-20% of power flow through the actuator disc:
Swept area of prop -area hub diam. * spec. weight of water/2 * boatspeed³

or
P actuator *Betz constant (.59)* prop efficiency( .4 to .7)

 

[Yobarnacle]

The shape of propellers and turbines is different. The adjustable pitch propeller wouldn't be adequate. to change into the efficient turbine. I wonder if a quick change prop could be employed on a tilt-up electric outboard. . Use the outboard with prop for in harbor propulsion. Offshore, use the turbine blade for producing electricity under sail. Not elegant, not good for emergency power unless the turbine blade produced some thrust, but the notion overcomes the dissimilarity in blade types.

 

[SolGato]

EPropulsions new line of Evo electric outboards have Hydrogenation capability.

For example, their 1KW motor can provide up to 330W at 10knt, their 3KW 660W, and their 6KW 1010W.

Brushless, PWM controlled, and they have a secondary power input for solar or axillery battery bank.

 

[Yobarnacle]

The props pictured in the ePropulsion advertisement below appear to be or resemble standard trolling motor type props. I wonder if a turbine bladed prop I post below would improve hydro-generation? Even if a loss in propulsion efficiency resulted, would the priority of generation warrant the change?

ePropulsion Introduces Seven New EVO Series Motors and Industry-First Hydrogeneration Capacities https://www.epropulsion.com/post/epropulsion-introduces-evo-series/

Kaplan/Propeller hydro turbine generator https://www.gmdu.net/product-55198.html

 

[SolGato]

The props pictured in the ePropulsion advertisement below appear to be or resemble standard trolling motor type props. I wonder if a turbine bladed prop I post below would improve hydro-generation? Even if a loss in propulsion efficiency resulted, would the priority of generation warrant the change?

ePropulsion Introduces Seven New EVO Series Motors and Industry-First Hydrogeneration Capacities https://www.epropulsion.com/post/epropulsion-introduces-evo-series/

View attachment 168426

Kaplan/Propeller hydro turbine generator https://www.gmdu.net/product-55198.html

You can’t change the prop on something like a electronically controlled motor without serious risk of damage as the motor controller has been designed specifically for the power and loads of that prop.

You can see that they have limited the hydrogen power to 10 knots.

It’s possible this is a limitation due to the controllers charging circuitry and the small battery.

Lithium batteries are designed to only be able to charge and discharge at a max current, so even if the motor was capable of more power at higher speeds, it might not be able to move that much into the battery, hence the limitation.

If you crunch the numbers, on the 1KW motor at 10kn the Hydrogenation can provide a max 330W. To figure out current, divide the 330 by the system voltage of 48V and you get almost 7 Amps which is about what you’d expect a typical plug in Lithium battery charger to provide.

When you look at the pricing difference between the standard Plus motor offering and the Evo offering with the Hydrogenation feature, you are paying about $500 for the Hydrogenation feature.

 

[Yobarnacle]

All true. However if the design priority was hydrogeneration, and propulsion only a secondary function, a reverse of the current priorities, then the controls would be set up accordingly in favor of hydrogeneration. Motor propulsion is most needed in crowded ports and low seeds are appropriate for maneuvering around other vessels.