tide/current energy

[beau]

I came across an article of a system which uses a float with a line attached to a pump attached to the ocean floor.
The concept uses the movement of waves and turbulance to pull on and activate a simple pump, producing high pressure sea water (800psi) which is then used as a desalinator before being used to drive a pelton wheel to produce energy.

The concept (in operation) is being used /developed as a commercial operation.
I was wondering if a smaller system could be developed for use on a yacht. The technology is pretty basic.
Any comments
Beau

[David M]

The concept is simple but I think the mechanics and the practicality would be difficult. I think having a solar cell or wind vane or both on deck makes a little more sense.

[Therapy]

Originally Posted by David M

The concept is simple but I think the mechanics and the practicality would be difficult. I think having a solar cell or wind vane or both on deck makes a little more sense.

Unless one could mount the pump arms on the bow and/or stern in such a way that they do not induce too much drag.

Maybe one to drop over the side while at anchor?

800psi....hmmm.

[scotty]

there have been two systems i have heard of the first tried basic impellers in tubes built into breaker walls, it was a total fallure, the second was more of a squirrel cage type unit that worked better but the total cost per watt was huge, something along the line of 20 times normal electric cost. this was a few years ago so the cost per watt might be down to 10 times or lower.

i also did read about a system to pump water miles inshore that worked well, i think the problem with the systems is its lots of power but spread out over time, which could be perfect for a desalinization system but bad for electrical generation.

i do think a system could be made using the up and down motion of a boat, heck they have the tow behind water makers, why not one set up to spin when the boat pulls it up. the only problem is it could not be a high flow system, but if its a 2 gallon a day unit that is basicly free to run who would complain

[beau]

In regards to David M, the problem with wind and solar is that sometimes there is no wind or no sun and then you have to gave a separate generator.

Tides and current are reliable.
Basically you are harnessing wind, tides and currents at the same time.
The power available is enormous if sized right, which on a boat should not be too difficult.
I agree it may be difficult to get the 800psi for desalination, but by using a piston type pump, not impossible for the low volumes required, considering the unit will operate 24/7.

Remember a japanese guy developed a boat propelled by the pitching motion of waves/boat.

[shadow]

I'm with Therapy, if you can get a unit that can be dropped while at anchor then that would be the best scenario. If it does work and generates adequate power/energy, combined with solar and wind, then you should be extremely self sustainable!! I'm all for it!! Hopefully, these technologies will be fine tuned and affordable enough to work with an electric engine by the time I purchase my boat.

Would love to be nearly 98% fossil fuel resistant. One could dream I guess!!

[Zanshin]

A Japanese inventor has harnessed the power of waves to propel his boat.

See World’s First Wave Powered Boat »» MetaEfficient Reviews

[Eleven]

Tempting indeed. As electric boats now tow their own generators we are not far from battery chargers that can be thrown over the side at anchor. UK has many boats 'moored alone' in tidal estuaries. 2knots, 2 amps at 12 volts.
There's the challenge. Just add weed and theft resitance to make it difficult.

[Ex-Calif]

There are a lot of wondeerful articles about Hories wave powered boat. What people don't talk about much is that he covered 3400 miles in 110 days. That works out to about 1.3 knots on average.

Some would say you can drift this fast.

Call me a non-greenie guarded skeptic regarding wave powered boats...

[denverd0n]

Originally Posted by Ex-Calif

That works out to about 1.3 knots on average.
Some would say you can drift this fast.

Exactly. The problem is that on this small of a scale wave power just cannot generate much energy.

I suppose that some sort of a wave-powered device that you can toss over the side while you're anchored may someday be a reality, but it is going to be EXTREMELY limited. We would all do better to hope for more efficient solar panels. At present the very best solar panels are only able to harvest about 20% or so of the solar energy that strikes them. There is a lot of room for improvement there! Imagine if your solar panels could generate three or four times as much energy per square foot--wouldn't that be nice?