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Alternative to Solar

9K views 62 replies 23 participants last post by  hellosailor 
#1 ·
Dear Community,
My name is Maximilian Allmayer-Beck and I am consulting a start up from Barcelona, which is working on an alternative way of generating energy on sailboats. The newly developed technology allows you to generate energy from the movement of the boat, store it and later on of course use this energy. Furthermore the device is waterproof, salt resistent and very low maintenance is needed. The whole device consists just of a box with two cables coming out. You can store the box for example under a bed and just plug in the cables to your battery.

However, what would really interests me now is how big such a device could be?
a) 100x40x40
b) 75x30x30
c) 50x30x30

How much it could weight?
a) 30 kg
b) 20 kg
c) 15 kg

How much power it should be able to produce?
a) 0,5 A ( = 6 watts)
b) 1 A ( = 12 watts)
c) 1,5 A ( = 18 watts)

Concerning the last point you have to keep in mind that solar power can produce more watts but only for a few hours a day whereas this device can produce power during 24h.
Any other feedback would be also very kind!
Thanks a lot!
 
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#2 ·
I have a high quality bare minimum solar system which peaks out at 2.5 amps and combined with my really low energy needs works out fine on a 29' boat that lives without any shore power on a remote mooring

It also keeps my two battery's very happy even during the winter when the boat is on the hard and NOT moving

The next step for us would be a small Engel drop in refrigeration unit which then raises the energy budget massively at which point I would have to add a bunch of stuff
 
#3 ·
Max, good luck with your project.

You'll find if you search around that many cruisers are using 50 to 200 or more Amp hours per day particularly if they have DC refrigeration (lots of variation around this based on climate and particular systems). Mostly 12 volt systems so you can do the power calculations.

Given the choices, even at 1.5 amps running 24 hours, you'd be making us 36 Amp hours. Not meeting all the needs, but making a good dent.

I don't think the size or weight is an issue if you can find a place to get the system low as to not greatly upset center of gravity. If I'm guessing right about your technology, the thing counts on rocking motion of the boat. If that's so, I think you'll find that most cruisers are sitting in the calmest harbor they can find most of the time, then taking a big trip, then sitting still again. That may be the biggest issue (again, if I'm guessing right about how it works).

Many of us wish there was a way to generate power without a wind generator, plugged into a dock, a solar panel, or some sort of engine running. Appreciate any effort to accomplish this.
 
#4 · (Edited)
It must be perfectly quiet.

The worst sound is one that comes from a rocking motion. You lay in your bunk, the boat rocks, and you hear a loose item go click, or a can roll in the cupboard, or a pot lid make a small bang. Then with every rock you dread what's coming, like the Chinese water torture. You know it's coming... here it comes... click!... then rock the other way... then rock back, here it comes... click!

The click seems loader than it is because you expect it and everything else is quiet. You dread it each time as you try to sleep. Even though it's a small click or bang it's the loudest thing on the boat. And hear it comes... CLICK!... then rock the other way... then rock back, here it comes... CLICK!... then rock the other way... then rock back, here it comes... CLICK!... then rock the other way... then rock back, here it comes... CLICK!... then rock the other way... then rock back, here it comes... CLICK!... then rock the other way... then rock back, here it comes... CLICK!... then rock the other way... then rock back, here it comes... CLICK!... then rock the other way... then rock back, here it comes... CLICK!... then rock the other way... then rock back, here it comes... CLICK!... It's madness I tell you, madness!!

You get the idea.

Regards,
Brad
 
#5 ·
Well I think the obvious answer to how big and how heavy would be, it depends. I'd be willing to put up with a bigger, and heavier, device if it produced more electricity. If it is the size of a box of tissues, weighs little, and costs little, then I won't mind if it produces little electricity. If it takes up the entire space under a berth, weighs a ton, and costs thousands, then it had darned well better produce almost all the electricity that I need!
 
#7 ·
However, what would really interests me now is how big such a device could be?
a) 100x40x40
b) 75x30x30
c) 50x30x30

what are the units of measurement here, inches, centimeters?

How much it could weight?
a) 30 kg
b) 20 kg
c) 15 kg

if the power produced was worth it none of these weights are an issue to me

How much power it should be able to produce?
a) 0,5 A ( = 6 watts)
b) 1 A ( = 12 watts)
c) 1,5 A ( = 18 watts)

at such low output the unit would have be almost free as I could add another panel to my solar at less than $1/watt

Concerning the last point you have to keep in mind that solar power can produce more watts but only for a few hours a day whereas this device can produce power during 24h.

true, but that is why I have batteries to store the power so I don't really care if I'm not making power at night
What happens to power output when it is calm out since it requires movement?
 
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#8 ·
I would really like to see some numbers coming from the little box with wires. There are lots of issues with accelo-generators that have quashed this idea for, oh, the past 150 years.;) The basic idea works -- and it works well on very small scales (self-winding watches) and very large scales (tidal generators). The keys there are minimal output energy requirements (wristwatch) or extremely powerful energy inputs (a few million tons of moving water).

Work is work: a force applied over a distance. To reap watt-hours from an accelo-generator, you need a very heavy weight, or a very large input acceleration, or a really long stroke. Preferably all three. One horsepower (~750W) is equal to lifting 550lbs one vertical foot in one second. Let's say the weight in the box is 15kg (33#), the pendulum stroke is 8", the acceleration under frisky conditions is 0.5g, and the conversion efficiency factor is 50% (that's extremely generous). Back of the envelope calcs suggest 2.75 watts out of such a device., or 0.2A.

Now where do you put it? Boat motion is greatest outboard and at the ends -- but you don't want heavy stuff or accelerated masses on the ends of your boat, or outboard. There's the issue of hysteresis: the device is going to lag behind the phase motion of the boat, esp. in erratic seas, cutting efficiency further. Most boats spend most of their time in a marina or harbor, chosen and designed specifically to minimize motion from waves.

It's a neat idea, I guess; but I'm always deeply suspicious of fractional horsepower electrical generating devices, especially on boats. How about doing what inventors used to do: Build the magic box, put it on a sailboat, show us third-party verified power outputs when attached to an actual load, and then go looking for someone to capitalize & manufacture it? I'll be thrilled if it works, might even buy one, but til then it's just mo' RE vaporware.
 
#9 ·
Since I've got a bigger boat than many on here, size it not much of a concern to me. If this unit is a one time install, requiring no maintenance and removal/repair/re-installation, then weight isn't a big factor either. My daily energy use is probably not that much different from a smaller cruiser, so it comes down to output. If your unit will produce a maximum of 1,5 A ( = 18 watts) underway, what could it possibly produce in a calm anchorage or mooring? For most cruisers, I doubt that 1,5 A ( = 18 watts) 24/7, even at anchor, would be worth a whole lot of money or the space.
Should you be able to get an average of 10 amps of 12 volts in a calm anchorage or mooring, then I think everyone here would scrimp, save and sell their mother in law, to get one aboard.
 
#10 ·
First of all, thank you so much for your quick response and the valuable feedback you gave me so far! In order to quickly response to a few things now:

1.@ Bene55 --> Yes, the device is absolutely quite without making any noise!
2. @capt vimes --> thank you very much for the link!
3. In order to answer the rest of the questions I will talk to my technical team tomorrow and I for sure can provide you with more details by then.

Thanks again for now!
Looking forward to receive more feedback about the idea.
 
#30 ·
That's another RE idea that pops up from time to time: human-powered electrical generation. It's not too bad in some ways, but its primary value is illustrating (in ways we can comprehend) just how freakin' difficult it is to make meaningful amounts of electrical power. A fairly fit athlete -- and most cruisers are not all that ;) -- can produce 1/4 to 1/3 horsepower during vigorous exercise: bicycling, rowing, x-country skiing. Maybe half a horsepower in short bursts, but figure a quarter to a third ongoing.

One horsepower is 746 watts. Pedaling or rowing like the devil, with an efficient direct-drive PM alternator, will produce ~200W. That's real electricity for sure, but it also means you'd need to hold that pace for five hours to generate as much power (1 kWh) as 200W of solar panels on a medium-sunny day. Your refrigeration may use that much juice in a warm climate.:) It's good exercise, mind you; and in the RE world, some Watts is better than no Watts, as long as the means of generating them don't excessively ruin other aspects of the boat, like weight distribution, windage, stowage room, or cruising budget.

Speaking or ruining the budget ... a Watt&Sea tow generator will produce that same 1 kWh in about four hours sailing at 6kts. It also only works while under way. And a high-output aux generator or engine alternator will take just about an hour to bank the same. No surprise that, faced with depleted batteries and set of bicycle pedals, most sailors would reach for the ignition key.;)
 
#31 ·
I would be curious to know if the startups have considered the size of their target market(s) verus the size and capacity of the product.

On a 45' boat there's plenty of room for a large suitcase. On a 28' boat, there's hardly room for a shoebox. The power needs of the two will be radically different, and the market is also very different. 90% of the sailboats sold in the US (a market which may differ from the EU) are something like 26' and under. And the total number of recreational sailboats sold in a good year will still be in the low 4-figures. Very low, IIRC.

Which means there may or may not be a market for 100 of these boxes, in the EU or the EU, in any given year, if they can gain a 10% market capture. Even if these numbers are off considerably...You'd need a very small box with very high output power, to be able to cover both ends of the tiny marine market with it.

Have they given consideration to that? Not "how much power, what size" but "how much power, what size, for which of the tiny markets?" And at what cost, for a complex(?) device compared to a simpler solar panel?
 
#33 ·
I'm a big fan of Edison batteries. They last forever. And as long as you don't overcharge them, are perfectly safe. (IIRC, you can overcharge them 25% - and some people do, on purpose -- but more then that is dangerous.)

Regards,
Brad
 
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#35 ·
I have two 100w panels, mounted on completely adjustable pivots. Combined with a small Isotherm SP fridge unit and all LED lighting, they supply more than enough wattage for everything, including the SSB and computer. These last two units are the biggest draw and have to be rationed but that has not been a problem. Even on cloudy days they produce a surprising amount of energy. IMO, this system would be hard to beat. It is virtually maintenance free, completely quiet, and effective. To me, the whirlibird wind units are totally obnoxious and an infringement on everyone's "sound space."

As there is almost always current running at anchorages, it would be nice to see someone invent some sort of collapsible water wheel to take advantage of it.
 
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#37 ·
As there is almost always current running at anchorages, it would be nice to see someone invent some sort of collapsible water wheel to take advantage of it.
Once again, we're stuck with the physics of the thing. Lets imagine a 3kt tidal current at anchorage (that's quite a lot) and pretend our collapsible water wheel is 3' in diameter and perfectly efficient at capturing the moving water's energy. 3kts=5 ft/sec; circumference of wheel is 9.4ft; wheel turns about 30 rpm. Ain't no alternator under 5,000# produces meaningful amps at 30rpm. A 16" axial flux unit with rare earth magnets starts producing well around 300 rpm, tends to hit its peak around 500rpm. You need lifting blades that can spin faster than the fluid to get that sort of hub speed -- and no, you can't use gearboxes or pulleys with a fractional horsepower generator.;) You're not producing enuf torque for that, and you'll lose over half your output to friction.

Wind turbines don't need to be noisy, but the only way to get decent amps out of small ones is to spin them very fast; that's the root cause of the noise. When you have 2' blades and only 13 sqft of swept area, plus a small (light) alternator, there's very little power or torque to draw from. You need to design your blades to spool the alternator up to peak speed very quickly -- tip speed ratios of 13 are normal on units like the AirX. You gain output in lower winds that way, but you also reach blade overspeed at about 14kts. Then they start to hammer. Units with more, fatter blades (like the Ampair or smallest Kestrel) run slower, produce more torque, and are generally quieter, but their light air output is poor.
 
#40 ·
All the calculations done in earlier posts are great - thanks - I learned something today.

Here's the first calculation I would have done:

1) Amp hours drawn per day all systems = Approx 120
2) No. of hours spent on anchor = 24
3) No. of hours spent trying to make sure we have total peace and quiet in the anchorage = 24
4) Resultant movement of vessel in any given direction: If No. 3 is done to any level of success = Zero (assuming tidal rise over 6 hours is ignored)
5) Energy produced at any output and from any location you choose to mention = Zero.

Thanks but my solar array at least works for half the day and the wind gen for the other half and that's good enough for me.

Sorry if I'm a bit of a pessimist in this debate.
 
#41 ·
Considering the fact of being at anchor, I wonder if the pull of the boat against the anchor could somehow be harnessed as a boat continually swings in the wind. Considering the tremendous current that runs through some spots like the Ft. Matanzas anchorage and others on the ICW or on the Hudson River makes me think that there must be a way to convert some of that energy while anchored.
 
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#42 ·
O-
Why be a pessimist, when the mechanical problem was solved some 60 years ago (self-winding wristwatches) and updated more than a decade ago with Seiko's "Kinetic" series, which use a small dynamo to generate electricity to power their watches the same way?

Bobbing, rocking, rolling, all could easily turn a dynamo and generate electricity. How much motion, how much bulk, how much cost, how much output, these are all trivial variables compared to the larger question of a tiny niche market.

There are much larger projects to use ocean tidal/wave motions to turn dynamos in a similar way. of course, they're on a much larger scale and unlike boats, those locations are chosen to be in motion rather than at calm rest.
 
#45 ·
Yes maybe you're right but the fact is that a kinetic watch uses absolutely minute amounts of electricity. Multiply the generated power by 1000 and that technology will probably provide enough power to run one LED but you have a device that won't fit into your boat. And Seiko Kinetic holds as minute a portion of the watch market - if they were that good we'd all be wearing one.

Also, the first generator that was designed to use wave action was done over a century ago and still very few have lasted or keep working anywhere in the world. The list of inventions is long, the money poured into it is immense, the list of successful installations is pitiful.

And then of course I believe the point of my post went by you - I make a considerable science out of finding places to anchor were my boat will not bob, rock or roll. The harder I try and the better I get at it, the less any such device will deliver. I can't see any sailor choosing a rolly anchorage just get back 10 amp hours over a night. It's a contradiction in terms.

And finally, my pessimism lies in the fact that energy world wide is a trillion dollar industry and hundreds of millions of dollars of R&D have not yielded a system like this and now someone is developing one in their garage? Especially for yachts?? Yes of course they are. I can't wait.:rolleyes:
 
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#43 ·
I've always wondered why the East River around Hell Gate or Woods Hole have not been harnessed somehow to generate electricity. Wind blows sometimes, tide always runs. In Woods, it would seem better than the hairbrained idea of constructing wind turbines in Buzzard's Bay.
 
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#47 ·
I'd heard about that years ago. Every time I look at one of those GIGANTIC container ships, it occurs to me that if the energy in their displacement being moved up and down by the rise and fall of tide, could be somehow converted to mechanical rotation, it'd have to be a lot of ergs.
 
#46 ·
It's true that we try to find the calmest spot to anchor but in my experience, those spots are quite often not in the plan. Unfortunately when traveling longer distances, it's a case of choosing the best of the worst. If I remember correctly, Bill Gates did something of some importance in a garage:) The sailboat and cruising market is miniscule. I think there are probably many, many useful inventions yet to be discovered.
 
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#48 ·
smurph-
The Hell Gate is comparatively shallow. About a hundred year ago the government tunneled under the river bottom, set off one of the biggest explosions in history, and dropped acres of the bottom down about ten feet in order to gain some depth. (Incredible project, very interesting reading.) So obstructing that passage with anything in the water would be a fast no-go.

The project in the East River, to the west of Welfare Island, was supplying power IIRC to the supermarket on the island but they've spent years trying to get it to work consistently and to study environmental issues like fish kills. Apparently putting windmills underwater just hasn't been working out very well, which is one reason folks are trying "motion" shakers and other concepts.
 
#49 ·
Yeah, it's always seemed like a bad idea to try to put any kind of turbine underwater except in small applications such as small stream generators designed for individual use. Those can just be cleaned out by hand and they really don't produce a whole lot of power for the cost. There's so much stuff like old pilings, etc. around NY Harbor that anything underwater I'd think would be constantly at risk of clogging. There's probably not much elevation change along the E. River to get a decent head of water in either direction such as with a typical river flowing downhill.
 
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