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Using the Pressure of Water and Rising Bubbles to Produce Energy

11/04/2019 9:10 PM

SeaPower description

Attached is a diagram that details a new energy generating power source using the expanding rise of air underwater as a lifting force.

This is the same principal that keeps a boat afloat.

In the diagram, there is a linear row of balloons. The lower balloon or inverted umbrella; is injected with 300 cubic feet of air compressed to 18 ATM resulting in a volume of 16.66 cubic feet of air.

When the first balloon rises 99 feet (3 ATM) a second balloon attached to the first one is injected with 300 cubic feet of air compressed to 16.66 cubic feet of air.

In the diagram provided this process is repeated having five (5) balloons rising. The upper balloon at 3 ATM has a lifting force of 6.400 pounds

The next balloon at 6 ATM has a lifting force of 3,200 pounds

The next balloon at 9 ATM has a rising force of 2,133 pounds

The next balloon at 12 ATM has a lifting force of 1,600 pounds

The next balloon at 15 ATM has a lifting force of 1,080 pounds

---------------------------------------------------------------------

Total pulling force is a continuous lifting force of 14,413 pounds

This mechanical process can be converted to electrical output.

If it takes less power to keep the system running than the output created; then this is a positive idea. If not; this is a dead horse with nowhere to go.

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#1

Re: using the pressure of water and rising bubbles to produce energy

11/04/2019 9:50 PM

"This is the same principal that keeps a boat afloat."

No, it isn't.

An object will float if the gravitational (downward) force is less than the buoyancy (upward) force. So, in other words, an object will float if it weighs less than the amount of water it displaces. This explains why a rock will sink while a huge boat will float. The rock is heavy, but it displaces only a little water.

Bubbles won't make boats float. They reduce the density of water.

How Do Boats Float ? | Wonderopolis

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#2

Re: using the pressure of water and rising bubbles to produce energy

11/04/2019 9:52 PM

This concept is completely DOA.

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#3

Re: using the pressure of water and rising bubbles to produce energy

11/04/2019 10:10 PM

I expect most salvage divers are already intuitively aware of how to lift an object with air from a scuba tank.

What you may not realize is a hazard in this process is every balloon has a maximum volume it can achieve before it breaks. One single balloon that breaks before reaching the surface will frequently cause the entire payload to fall back to the lake/ocean floor.

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#4

Re: using the pressure of water and rising bubbles to produce energy

11/04/2019 10:38 PM

If not; this is a dead horse with nowhere to go.

Sorry, I think you will find after a little more examination of this buoyancy idea that your dead horse will just float to the surface.

No free lunch here with this particular conceptual energy proposal.

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#5

Re: using the pressure of water and rising bubbles to produce energy

11/04/2019 11:14 PM

You can't create energy....Energy can be changed from one form to another, but there is always a loss due to lack of efficiency usually in the form of heat, you can never achieve 100% efficiency, and even if you could you are still only trading even, so you must have energy to begin with, and there you go right back to where you started...If you have energy to begin with, you might want to change it to a form better suited to your needs...but if you don't have any energy, well then, you don't have any energy...Placing a balloon apparatus under water requires energy to pump the air down to the balloons, or compressing air to drop down the water column, you have converted energy to potential energy, but you have spent energy in doing so, now all you can do is release it....

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#6

Re: using the pressure of water and rising bubbles to produce energy

11/05/2019 3:07 AM

• Where does the power come from to generate <...300 cubic feet of air compressed to 18 ATM...> (rhetorical question - NNTR)?

The statement <...This is the same principal that keeps a boat afloat...> is nonsense, as well as incorrectly spelled.

"Getting something for nothing" is a fundamentally unavailable concept within this universe. If it weren't, then it would spontaneously explode and cease to exist.

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#22

Re: using the pressure of water and rising bubbles to produce energy

02/25/2020 8:55 PM

The question is; is this possible, do the numbers add up?

It takes (X) amount on energy to fill one balloon with air at 18 ATM

That balloon rises and another balloon attached to the first is injected with (X) amount of air (X1)

That balloon rises and another balloon attached to the first is injected with (X) amount of air (X2)

That balloon rises and another balloon attached to the first is injected with (X) amount of air (X3)

That balloon rises and another balloon attached to the first is injected with (X) amount of air (X4)

That balloon rises and another balloon attached to the first is injected with (X) amount of air (X5)

now you have five (5) balloons attached to each other pulling together creating more lifting force than it took to fill the first one

(X)+(X)+(X)+(X)+(X) has a greater lifting force than (X)

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#23

Re: using the pressure of water and rising bubbles to produce energy

02/25/2020 9:48 PM

Divers use this method to lift objects from the sea floor all the time, so of course there's a calculator for that...

This is an example of air volume needed to lift an object 1000 lbs in weight and 6 cu ft in volume from the seabed 180 ft below......

..."Object in Salt water at 180 ft, weighing 1000 lbs with a volume of 6 cu ft.

A lift capacity of 616.4 lbs or 9.6 cu ft is required.
The lift bag will use 62.2 cu ft of air at 180 ft."...

https://www.divebuddy.com/calculator/liftbag.aspx

So you would need a standard 80 cu ft scuba tank roughly speaking to lift 1000 lbs....cost about \$5 for each fill up...doing it yourself with a surface pump and long hose probably cheaper...

https://www.divegearexpress.com/library/articles/calculating-scuba-cylinder-capacities

Now if you could produce a gas at that depth from the seawater itself that would be a way to go...

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#24

Re: using the pressure of water and rising bubbles to produce energy

02/26/2020 1:54 PM

"Now if you could produce a gas at that depth from the seawater itself that "would be a way to go...

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#26

Re: using the pressure of water and rising bubbles to produce energy

02/26/2020 2:22 PM

Geothermal vents are generally very deep in the ocean....

https://en.wikipedia.org/wiki/Hydrothermal_vent

But a reliable source of heat....where there is heat there is a potential for energy production...

http://www.halfbakery.com/idea/Geothermal_20Power_20from_20Hydrothermal_20Vents

It seems to me to be something that would be prohibitively expensive and problematic, but could in theory be done....

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#7

Re: using the pressure of water and rising bubbles to produce energy

11/05/2019 3:10 AM

You will always require more energy to "inject" and "compress" the air, then the system will give you back.

"If it takes less power to keep the system running than the output created; then this is a positive idea. If not; this is a dead horse with nowhere to go."

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#8

Re: using the pressure of water and rising bubbles to produce energy

11/05/2019 3:46 AM

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#25

Re: using the pressure of water and rising bubbles to produce energy

02/26/2020 2:05 PM

There are four (4) horses pulling this wagon

Why not just use one horse, when it tires hitch up another, letting the first rest; repeating this process as each horse tires.

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#30

Re: using the pressure of water and rising bubbles to produce energy

02/27/2020 4:39 PM

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#9

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/05/2019 10:06 AM

In short, it may be a way of storing energy, but not of creating energy. Any energy that is released belongs to the guy that compressed the air, which, of course, requires energy.

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#14

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/10/2019 1:29 PM

Correct of course. It got me thinking where this might be useful for energy storage. Ship locks or lifts, dry docks, marina cranes, movable sea wall, movable bridges, flood control gates on dams. A small wind turbine could slowly, freely compress air to keep an underwater lifting chamber topped up. That very large lifting force is then available all at once(some very strong trigger) on a low frequency basis. It could be a primary source of operational force in very remote areas, or as a zero electricity failsafe backup for critical systems. This would be too expensive to implement completely independent and redundant of a traditional setup, but traditional compressors(reciprocating electric, natural gas, steam turbine) could be added to this to increase the cycle frequency.

Tangentially related day dreaming follows:
At a dam structure, imagine a uniform string of air filled steel spheres connected in a loop. The upper end of the loop goes over the dam, the lower end goes through a lock mechanism in the wall of the dam. The half of the string in water(upstream of dam) wants to rise, the half in air(downstream of dam) wants to fall under gravity.

On the surface of it this looks like a perpetual motion machine, so I would like help identifying the losses. Would it ever start, or would it run for a while and achieve equilibrium? The lock mechanism where the downstream spheres pass through the dam to the upstream side must be the major source of loss, but I don't know how to quantify it. As the string of spheres gets doubled in length, the force available increases on both sides of the dam, and the lock also gets deeper by half the increased length. The lock must leak some water which runs counter to the direction of loop rotation, but I have no idea how to approximate the amount. That leaking water comes out at higher kinetic energy and less potential energy than water flowing over the top. Not sure if that factors in either. Would the principles change if instead of a string of spheres, it were a single large toroid? Internally segmented toroid?

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#15

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/10/2019 10:17 PM

None of that would work...but you could employ a water wheel as the source of power...

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#16

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/11/2019 12:44 PM

There was a lot of different things in that post. Are you sure NONE of it would work? Maybe provide a single reason? A water wheel only works where you have flowing water, not the situation here.

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#17

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/11/2019 1:21 PM

Sure, give a sketch of the your most promising idea...

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#18

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/11/2019 2:51 PM

The water behind the dam is already stored energy, and that energy can be converted to other forms, such as to electric energy via turbines and generators/alternators. If anyone can find a more efficient method of converting the potential energy of the water into some other useful form of energy, they should be very rich very quickly.

The air filled steel spheres are way worse than the balloons, since the enclosed air is not allowed to expand as it rises. You'd be slightly better off evacuating the spheres.

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#19

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/11/2019 4:31 PM

You could split the water into hydrogen and oxygen, if you have enough demand to support profits....or you could purify the water and sell it in bottles...The monetizing of the water to pay for the energy can take many forms....

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#20

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/11/2019 4:39 PM

Understood. In fact the air filled steel spheres are made from neurons at this point. I'm not expecting to get rich, or for it to even work. Its a "what if" that has gotten under my skin. This is what's bugging me.

1. What is a specific mechanical reason it wont work?

2. Even though it has a prerequisite of dammed water, it does not appear to consume (enough)potential energy to produce kinetic in the amounts suggested by the masses. Yes, I understand that #2 could be considered an answer to #1.

3. I can visualize it working as a string of beads but cannot visualize it working as a toroid. Like a long balloon with the ends joined together. But I cannot identify the principles that make them fundamentally different. I see this as a failure of my imagination, which I guess is my real motivation.

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#21

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/12/2019 12:05 AM

1. The energy required to operate that sealing device at the bottom of the dam, where the balls or toroid enter the water, would (I suspect) be greater than the energy available from the slowly rising balls or toroid.

2. "Even though it has a prerequisite of dammed water..." Sort of... the chain of balls could just as well be rising through a vertical tube of water. As long as the tube is large enough to minimize turbulence of the water flowing down past the rising balls, it would be equivalent to the balls rising through the much larger volume of water behind the dam. Whether a tube filled with water is "dammed water" is a matter of semantics.

3. I too have greater difficulty visualizing the forces acting on the toroid. But the action is the same: each ball will have a net upward force due to the greater pressure pushing up on the bottom half of the ball and the lesser pressure pushing down on the top half of the ball. The underwater half of the toroid will likewise have a net upward force due to the greater pressure pushing up on the bottom quarter of the toroid and the lesser pressure pushing down on the top quarter of the toroid.

If you've ever seen the water rushing out of the turbines at the bottom of a dam, or through a valve at the bottom of a dam, you should realize that forming any kind of seal that would allow free movement of the chain of balls or the toroid would be essentially impossible. Likewise, although I've not done any math on it, I suspect that the outward force (due to the pressure of the water at that depth) on whichever ball is trying to enter the bottom of the loop, would be greater than the total buoyant force on the balls.

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#29

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/27/2020 4:37 PM

In order to quantify your design; I would need a drawing of it.

Can you provide it-?

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#27

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/27/2020 3:53 PM

At least the mods here have not banned me for gibberish.

On another talk board my fantasy drawing got this response--

"You have been banned for the following reason:

No impossible machines - you still do not understand basic physics of conservation of energy.

Date the ban will be lifted: Never"

Engineers Edge - Reference Data for Engineers | GD&T ASME Training | GD&T Training | DFM DFA Training | Engineering Supplies Store | Engineering Tools for productivity

All I can say is thank you mods for letting me talk no myself here.

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#34

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/28/2020 12:06 AM

Kudos to Engineers Edge. Some forums don't even ban or delete outright lies, imputations of mental illness, or improper ad hominem attacks/fallacies.

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#31

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/27/2020 5:31 PM

I’m in such a knee jerk mode I didn’t even read your entire response expecting it to be just another attack, my bad.

I have not looked at this as a means to store energy.

I see it as rather a way to multiply the kinetic force of matter, being the displaced water.

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#43

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

03/26/2020 8:51 AM

It’s not an attack, it only feels that way...

And since there’s no convincing you on your ‘dream’,... heres a challenge, prove us wrong.

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#10

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/06/2019 4:09 AM

Now that is a thought. Replace the balloons with recently dead horses which as they decompose generate gas internally and raise the conveyor to generate. Of course once they reach the surface they need to be disposed of and replaced with freshly culled horses at the bottom.

I expect the animal liberationists to picket my blogs but that is ok for they be used to remove the spent horses.

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#11

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/06/2019 10:48 AM

Basically a description of a perpetual motion machine. In the end, it takes more energy to inject the air into the bottom balloon than you get back when it rises.

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#12

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/06/2019 11:30 AM

First, I hate "Not to Scale" drawings. For anyone who uses drawing regularly, such drawings are always misleading. As a minimum, show your bubbles getting larger as they rise, according to your numbers (which I did not bother to verify).

Second, compressing air is an inherently inefficient process, with large losses to heat. That heat kills your horse!

Third, a bubble of any size can only rise when the water above it flows around and then underneath it. That flow wastes more energy, flogging the already dead horse.

Fourth, due to the above flow, bubbles only rise very slowly. Converting that slow motion into any usable form of energy is very difficult, unless perhaps you are dredging the sea floor.

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#13

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

11/06/2019 12:59 PM

I wonder if the OP has left out some detail or is leaving it to us to apply the concept to something useful or doesn't fully understand the idea he/she has? To me what the OP has done is quantify the mechanics of a float system, nothing more.

If you have this apparatus with 14,4k pounds of buoyancy at a fixed depth tethered to the sea floor somewhere near the coast where there is regular wave action you could take advantage of the rise and fall to harvest wave energy. If the energy needed to maintain constant internal pressure and depth is less than the harvested energy you might have something useful. What is needed is the counter buoyancy mechanism and device for converting the excess energy into electricity.

Alas - none of this is new. Not even the basic idea of using pneumatic balloons. Wave energy harvesting has been around for quite a while.

So - kudos for doing the math and diagram, demerits for not researching prior work. Double demerits if it was researched and copied from prior work.

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#28

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/27/2020 4:07 PM

You are more than welcome to expand on that idea, start a thread.

A gas bubble will expand proportional to the water pressure applied upon it.

The lower the pressure, the larger the bubble expands. This expansion displaces the seawater. For every cubic foot of water replaced with air (gas) the bubble will have a lifting force of 64 pounds.

As the bubble expands its lifting force increases proportionally.

(Y) or (N)

.

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#32

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/27/2020 9:49 PM

No...

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#33

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/27/2020 11:46 PM

Proportionally to what? Diameter, height, area, volume, or something else?

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#35

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/29/2020 1:52 PM

proportional to the pressure of the seawater. The air bubble expands as the pressure gets less. As the bubble expands the lifting force of the bubble increases.

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#36

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/29/2020 3:01 PM

Compare the weight of a cubic foot of water at 1000 ft altitude with a cubic ft of water at sea level....Does the water weight the same?

https://www.nytimes.com/2003/12/23/science/q-a-altitude-and-weight.html

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#37

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

02/29/2020 11:20 PM

The standard gas equation is PV=NRT, so V=NRT/P. T is likely to rise slowly as the bubble rises. For a given bubble, NR is a very close to constant.

Thus, assuming that the lifting force of the bubble is proportional to the volume of the bubble, and that the pressure is linearly proportional to depth, the liftng force is close to inversely proportional to depth.

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#38

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

03/01/2020 1:00 AM

Object in Salt water at 90 ft, weighing 1000 lbs with a volume of 6 cu ft.
A lift capacity of 616.4 lbs or 9.6 cu ft is required.
The lift bag will use 35.9 cu ft of air at 90 ft.

Object in Salt water at 180 ft, weighing 1000 lbs with a volume of 6 cu ft.
A lift capacity of 616.4 lbs or 9.6 cu ft is required.
The lift bag will use 62.2 cu ft of air at 180 ft.

As the volume of the air increases so does the drag potentially, the rising rate might hit as high as 100 ft per minute near the surface....nearly doubling in speed...

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#39

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

03/01/2020 8:20 AM

Increasing or decreasing lifting force (buoyancy) depends on the unstated reference. In other words, is the position (depth) measured from sea floor or surface level.

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#40

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

03/01/2020 2:06 PM

Proportional

Bubble expands as pressure decreases

Upward force increases as bubbles expand

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#41

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

03/01/2020 2:38 PM

In my last post, I said: "...the lifting force is close to inversely proportional to depth." (underline added in this post).

You say: "Bubble expands as pressure decreases

Upward force increases as bubbles expand"

Those statements are both correct, and pressure decreases as depth decreases, so Upward Force increases as depth decreases. That's an inverse proportion.

You can make it a direct proportion if you use distance from the bottom, rather than depth.

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#42

Re: Using the Pressure of Water and Rising Bubbles to Produce Energy

03/01/2020 10:04 PM

When divers use this lifting technique they use an open bottom bag to prevent the expanding bubble from rupturing a container. The excess gas during ascent just leaves the bottom of the bag.

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