Combined breakwater and wave power generator


#41

Sorry, @Georgeb, but you are pontificating in ignorance.

The entity called surface wave has a specific meaning.

The entity called swell has an entirely different specific meaning.

Don’t be ignorant. Be educated. Read the link I previously posted, google those words, and then study the scientific literature.

Otherwise you will remain confused about the issues and the problems you are trying to address.


#42

@Georgeb -

Start with the simplicity of Wikipedia, learn some accurate definitions, and then start reading some of the scientific referenced included in the Wikipedia articles.


#43

#44

#45

#46

#47

Technically, Einstein, energy and mass are just two different manifestations.

But, no, a “breakwater” exclusively uses the mass inherent in the physical earth upon which it is attached to counteract (“break”) the water. That’s why the breakwater doesn’t float away … because it is ATTACHED.

Otherwise, any floating object you want to name the SS BREAKWATER would need to have more mass than could possibly be moved by the energy contained within surface waves.

And, since entire coastlines are destroyed by surface waves impacting upon the earth, one can assume your SS BREAKWATER would need to be extremely massive if you don’t want the SS BREAKWATER to be pushed around (eventually colliding with land) in the open sea.

If you want to break water on the open sea, either attach your “breakwater” to the earth under the sea OR create such a massive structure that your SS BREAKWATER is effectively considered an “island” in itself … which negates entirely your purpose of creating a “breakwater” to protect the seastead.

Please stop trying to argue to win your point, @Georgeb, and consider the thing you are trying to accomplish.

You want to capture energy from surface waves.

Creating a massive structure (breakwater) merely to capture a lesser amount of energy than is necessary to build and maintain the breakwater is a foolish exercise.

Concentrate on the portion of your proposal that CAPTURES energy by somehow transferring it into your electrical generation plan. THAT has potential.

But transferring the energy contained within a surface wave into your massive structure called “breakwater” is a wasted transfer because, to get energy back from that structure, you’ll need to consume energy by lifting (and then letting gravity drop … so that now “energy capture” can finally create electrical power) a portion of the structure, itself.

You want to create a floating platform to lift water and subsequently create electrical power when gravity pulls the lifted water downward.

THAT is not a “breakwater”.

From an entirely different perspective, there is a need to eliminate swells (created by surface waves) from under a floating seastead. A “breakwater” does not do THAT, unless the mass of the structure is large enough to oppose all of the open-sea forces of surface waves.

But DISSIPATING the energy (aka, surface waves) eliminates the swells, regardless of the dissipation method.

Problem of swells is gone when the surface wave no longer exists. The seastead floats on a smooth surface. Problem solved.

How to BEST deal with the surface wave is the community’s question.

The “Wave Bridge” theoretically might work, but there is no other benefit to the community.

Energy transfer in an electrical generation scheme would work to minimize or eliminate swells … AND it would have the benefit of generated electricity.

But if MASS is first necessary as a platform to capture electrical energy, then some energy transfer is wasted.

The “breakwater” is mass.

However, if virtually ALL of the available energy (aka, surface wave) was dissipated (by electrical generation or some other dissipation mechanism), then there remains no surface wave to produce any swells.

As previously noted, a massive oil slick would do that via gravity.

A very large floating kelp bed or a mangrove forest would also work to dissipate the surface waves, as would a properly designed semi-submerged scaffolding barrier.

And, yes, a very massive SS BREAKWATER the size of a small island would work … but only if its horizontal distance parallel to the surface wave’s direction was large enough to absorb the surface waves peaking underneath it … AND only if that SS BREAKWATER island was structurally sound enough to not be torn apart by that constant pounding.

But simply floating a narrow structure that resembles a coastal breakwater is an idiotic attempt to “break water” on the open seas …

… because coastal breakwaters rely upon the mass of the Earth to oppose the ocean’s energy.

One need not be as smart as Einstein to figure that out. Just go watch a boat crash into a breakwater and observe which one wins.


(George busby) #48

I still think you are confused.
Think of waves in energy terms.
Waves consist of kinetic and potential energy. If you have no barrier the kinetic energy will push water onto the land and smash things onto the coast.
A conventional breakwater is a mound built up from the sea floor. The mound blocks the kinetic energy of the wave and converts the energy into potential energy such as spray and heat through friction. The mound is usually covered by rocks to increase the surface area and increase friction losses. The mound needs to be high enough to stop water with potential energy overflowing it.
The reservoirs when used as a breakwater block the kinetic energy of waves and converts this into potential energy by raising the water level in the reservoir. There will also be some small friction losses. The energy is absorbed by water in the reservoir rather than by the structure itself in conventional breakwaters.
Size is important because small reservoirs would get destroyed by big waves. Stored water is heavy and difficult to move and should give the structures stability.
I think you are very optimistic if you think you can deflect waves under a seastead. Waves can vary greatly in size and come from any direction so how could you deflect them all?


#49

Thanks for your patience. I think I’ve learned something, but let me know if I’m wrong. A seastead in the open ocean will need something to dissipate the energy of surface waves, but a breakwater (which relies on a connection to the ocean bottom) is not a feasible solution in deeper seas.


#50

Correct, @emperorofthesea.


#51

If you mean refract surface waves under a seastead

… the same physics apply, regardless of whether the refracting surface is positioned horizontally or vertically in the water.

Anyone who wants to build a floating vertical wall to “break” the energy of surface waves that “vary greatly in size and come from any direction”

… should consider the foolishness of doubting that those same waves would react differently when refracting off of a horizontal surface.

Refraction is refraction.

Angle of incidence is still angle of incidence.

The problem you refuse to acknowledge, @Georgeb, is that your verticle surface will result in the horizontal displacement of your floating barrier.

A horizontal surface will have vertical displacement … the surface wave will push the horizontal surface upward, and gravity will simply work in the opposite direction. Horizontal displacement is minimized.

Your SS BREAKWATER will need to expend greater energy to remain in place, or risk being quickly pushed back into the seastead you claim it will protect.

@JL_Frusha shared some links for you to read that referenced this problem. That is exactly the problem the theoretical “Wave Bridge” was intended to resolve.

I suspect you are not reading what others write and share, @Georgeb

… choosing, instead, to respond in ignorance.

Read the sources, @Georgeb. Don’t remain ignorant of what is being proposed.

Once again, I repeat …

… your vertical STORAGE idea has some merit, and kudos to you for brainstorming the elements of THAT concept.

But your arguments about floating “breakwaters” aren’t accurate. You are mixing apples and oranges, and claiming they are fruit … but then insisting your apples can make orange juice.

Sorry, but no … a floating vertical barrier - like your SS BREAKWATER - suffers from horizontal displacement, and it will consequently crash into the seastead it is supposed to protect.

You are trying to solve a different problem with the wrong tool.

Separate vertical storage from creating smooth waters for floating seasteads … and deal with those issues separately.


(.) #52

I am trying to post something constructive, but here we are.
French Polynesia: may be good. A bit far for me. But it is
not about me.


(George busby) #53

I am more interested in simple logic than pedantics.
When a wave strikes the side of the reservoir most of it will strike the doors of the openings. These doors will open if the pressure is greater than the pressure inside and water will enter to raise the water level in the reservoir.
Some of the the wave will strike the fixed parts of the structure and so there will be a small net horizontal force on the reservoir.
The reservoirs are fixed to piles in shallow water or secured by anchors in deep water. To move the reservoirs and the massive weight of water inside would require massive forces. I agree this would need testing in wave tanks.


(Navier-Stokes) #54

Hi there,
Please find the attached file with paper regarding an innovative breakwater integrated with a wave energy converter device. A full-scale prototype has been installed last year in Italy.


http://www.sciencedirect.com/science/article/pii/S0378383914000283
http://www.sciencedirect.com/science/article/pii/S0378383917300935

Best,
Enrico


#55

Thanks for the info on OBREC, @Navier-Stokes.

In ref to previous comments …

Land-based breakwaters, like OBREC, work because they are firmly attached to land.

Floating systems … float.

The opening and closing of “doors” or “gates” on a land-base system work ONLY because the land-based openings do not rise and fall relative to the water surface.

Once again … a floating ANYTHING cannot function as a breakwater because it cannot “break” the water.

Because it floats. Period.

It floats. As in … rises and falls with the water.


(Navier-Stokes) #56

You are welcome @BobDohse!


(.) #57

Research Platform FLIP (FLoating Instrument Platform)
https://scripps.ucsd.edu/ships/flip

My understanding of the flip ship is that it floats without being effected by the waves.
"… uniquely stable and resistant to wave motion …"
This is necessary, I guess, for its function to avoid the Doppler effect during detection of submarines.


#58

FLIP typically uses a 3-point tension mooring, to minimize motion. The anchors and chain are usually left behind, in deepwater moorings…

OPERATIONAL CAPABILITIES
FLIP can be used in either a drifting or moored mode, based on the science
requirements, and can remain on station in the vertical position for substantial periods
of time. For research requiring a stationary rather than drifting platform, a deep
moor capability has been developed. The first mooring made from a single moor
was in 5,500-meter waters north of Hawaii in 1969. Subsequently, a multiple anchor
capability evolved. It is now possible to place FLIP in a three-anchor mooring in
virtually any depth of water; in September 2001, FLIP was moored in a water depth of
4,242 meters, 250 miles southwest of Oahu, Hawaii.
Deep-water moorings usually take one day, from first light to past dusk, in waters
4,000-5,000 meters deep. A deep mooring requires about 80 tons of gear aboard
the tow vessel. Moorings in 4,000-meter water with a mooring scope of 1.5 have had
watch circles in the range of 80-200 meters, depending on currents. The mooring
lines are recovered and reused whereas the anchor and anchor chain (10 tons per
leg) are left on the bottom. Three-point moorings in the deep ocean are routine
operations, especially for deployment of acoustic arrays in which flow noise must be
minimized and acoustic navigation of array elements is required. The transponder
system for Array Element Location (AEL) can be surveyed in and tied to the GPS
navigation system with the GPS receiver aboard FLIP.


(.) #59

There you go. And twenty more characters.


(Chad Wiginton) #60

I glanced at superconductor levitation and wondered if it could be applied to solve that problem. Floating seastead tank?