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Author Topic: Buoyancy-Based Power Generation - Full Disclosure  (Read 44411 times)


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #15 on: August 18, 2010, 12:49:01 AM »
Fighting already? we're on the first page !!!! come on...

The B-Unit is a well tested and well proven device.
It can be scaled to lift any mass, the equation is simply determined by the volume of the fluid displaced by the buoyancy chamber.

Mass of B-Unit + Load = Mass of the displaced fluid.
This is a 0 Force , or Zero-B state. Weightlessness, and the default starting point of the B-Unit. This is controlled by a hydraulic cylinder actuated generally by 2 methods, though others have been applied in differing circumstances.
Method 1: electronic solenoid. This is not very cost efficient, but allows for quicker system response.
Method 2: worm-gear. This is much more cost efficient, in terms of resistive pressure vs energy input, however the buoyancy system takes more time to transition between states, which controls altitude, acceleration, and verticle direction.

The electrical cost of actuating the hydraulic cylinder is directly related to the buoyant force. The proportion does not reduce to an energy equilibrium, as depending on the fluid and depth/pressure, these two values can be equal to, greater than or less than one another.
but by analyzing data, a relationship can be drawn, such that an increase in resistive pressure relates directly to an increase in buoyant force. And inversley, a decrease in resistive pressure, relates directly to a decrease in buoyant force.

The denser the fluid, the greater the resistive presure. This is the force exerted on all sides of the buoyancy chamber (B-Unit).
This force resists the expansion of the chamber, E= f * d
Distance is determined by the desired buoyant force
This is the work done by the hydraulic cylinder.
In the Air, the difference in resistive pressure between an altitude of 0 to 200 ft (the lower limit of FAA aircraft control), is negligible.

The difference in resistive pressure between 0 to 200ft under water, is thousands of times greater. But so is the buoyant force.

The energy available from buoyant force imparted onto the B-Unit is determined by the distance of the 'lift'. Other than the direct proportionality, there is no E = E correlation betwee these two energy values. simply because the distance of the "lift" is determined by the container of the fluid, and or operational parameters set in place by the user. While the energy required to create buoyant force, is determined only by the pressure of the fluid at the start of the "lift".

This system is a complexity of several systems interlinked. Utilizing multiple force-vectors, from completely different systems.
a thermodynamic analysis of this as a whole, is not possible, because it is not a "closed system". Those rules simply don't apply here.

If you look at the B-Unit itself, as a point, lets say 200ft under water.   Now, the energy required to expand the unit is exactly equal to the energy obtainable by allowing the water pressure to collapse the unit. Those two values are thermodynamically equivalent.

This example also applies to the Emergency LifeJackets, used by Divers. Under 200ft of water, the energy required to inflate the life jacket is equal to ( or less than) the energy contained in the tiny CO2 cartridge.  However::  This has nothing to do with the energy gained by the diver as his inflated life jacket jettisons him to the surface.

have the diver hold onto a tension-cable anchored to the ocean floor, and you can measure this energy directly. E = f * d
Distance, in this case being 200 feet.
you can see, that while the energy value in different types of life jackets may vary,
this is only a proportional change to the buoyant force.
the total work ( force over distance) caused by buoyancy is many times greater than the work done by charging while CO2 cartridge or the work done by the compress gas to inflate the life jacket.

The determining factor for wether or not the B-Unit is being unsed in an "overunity" fashion, is simply the distance of the lift.
once you surpass the work-force if the transition, at height-x,
anything higher than that is "free energy".
It doesnt defy any laws of physics, infact the physics supports this entire system. It must be treated as several independent systems. The robotics and hydraulic systems are small, and consume a set ammount of energy per cycle.
The power generation is a completely different system, determined by the height of the "lift" and "fall".
you adjust the height, you adjust the power output.
power input changes proportionately on the "lift" side.
but this hydraulic actuation, is fractionally smaller.
Like the braking system on older cars, before they started using the engine to assist you.
your one foot isnt putting nearly enough energy into that heavy car to STOP it.
but by pushing with a great ammount of hydraulic-leverage you are able to tightly clamp the brake pads onto the rotor causing enough friction to stop the car. These are two completely seperate systems. one system increases and decreases the frictional drag on the rotors. how much energy is consumed by the rotating axle with this increase in friction has nothing to do with the energy required to cause it. the other system, is the car's engine using gasoline to make it move forward. this system is offset by the greatly increased friction of the brakes.
but the energy values (input to the brakes, and output from the engine) have only a factional / proportional relationship, because they are interfaced components of two entirely seperate systems.
If the two were equivalent, you would need a whole other gear-set for yoru transmission, for instance, if you were to link a clutchable "reverse" gear, whos purpose was to fight against the inertia of the car, you could stop just as fast as you accelerate.
but starting and stopping would consume just as much gas.

What else slows the car down? friction. hmm, we know how to add friction. this costs much less energy than "reversing" the driving process.
lets just give the car a friction-switch. we'll call this the "braking system".

Everyone accepted this system with open arms. Hey thats great! we can stop the car with a simple push of our foot, or a pull of a lever.

What i didnt hear them saying was that the laws of physics were broken, or einsteins would start falling from the sky, or that we were in a state of thermodynamic crisis. Why not? because those laws only apply to a closed system. Not two interfaced, variable, systems.

Now about the Water Leakage comment.

The door between the two tanks is sealed during the generation cycle. no water passes through the bottom.
At the top, there would be minimal 'drippage' from wet units transfering over to the short Side. this water-runn-off is channelled into the recovery tank, and the water-level of the recovery tank drains off to a drainage pipe, above the water-line.

so yes there will be manageble 'water-loss', which should be taken into consideration, but is not prohibitive by any means.

During the Reloading Process, both tanks are completely sealed off from the outside by the Tank Doors on top, and the door between the two is unsealed.
There is minimal water transfer during this phase, because of the pressure-equilibrium formed between the tanks.
The actual ammount of water that is transfered varies on the air-content, and respective compressibility factor of the water in the secondary tank, and the pressure exterted on it by the water in the primary tank. In any case, it is a small, and managable ammount of water transfer.


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #16 on: August 18, 2010, 12:59:29 AM »
Resistive Force on the B-Unit requires us to impart an increased ammount of energy in order to expand the unit, and have a positive B-Value. (negative weight)

In theory, we could store this energy, and extract it out at the end of the "lift", before reaching the top of the buoyant fluid.
This would be Energy in = Energy out, minus losses.

Now,. look down, because you have just increased your potential energy within the gravitational field by a factor of X
and it is about to be converted to kenetic energy as you fall.
(moment of silence)................

Resistive Force is exerted on all sides of the B-Unit, as a function of ambient fluid pressure.
We negate the force on the sides, and consider only the 'effective' radial force vectors that affect input energy.
mostly Top, and Bottom
and from the surface area of the B-Unit, we can determine the work force for a theoretical input energy.
In practice this input energy is greater, due to inefficiencies in the system.


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #17 on: August 18, 2010, 01:27:34 AM »
Potential & Kenetic Energy in Force Vector Power Generation:::

The potential energy at any point in a vector force field, such as a magnetic, gravitational, or buoyant field, is determined by the distance between the start and ending points of its motion through the field. In a gravitational field we call this "height".

E = mgh can also be represented as E = b'ad
b' is the objects "buoyancy factor" within the fluid, which is always taken as an |absolute value|

a is the accelleration factor of the field, this is a dynamic force, this becomes more apparent when working with dense fluids. in air, it is marginal at low altitudes.

d is the distance between two points within the field.

This Kenetic energy cannot be converted 100% without inhibiting motion through the field, except in the unique instance of 'free-fall' impact - which is not considered here.

We therefore, consider the minimumal contraints of required force, necessary to move the B-Unit distance x, over time t.
subtract this from the available field force acceleration (a)
And are left with the available production factor.
This production factor is the interfacing component between the buoyant force and the actual power generation.
which is again completely different system, we'll touch more on that later.

heres a visual of the potential energy scale through a vector force field.

Drawing AppC3:


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #18 on: August 18, 2010, 01:49:15 AM »
If we consider an ideal 'perfect' electromagnet.
   Where input energy, relates exactly to the energy contained within the field.

An object being drawn into the field has a thermodynamic relationship (conservatism) within the force vector. What i mean by this, is it requires just as much energy to pull the object back out of the field as you gained by allowing it to be attracted to the magnet.

Now, when you compare the Force is the field, as it pertains to acceleration imparted upon the object, this is directly proportional to the energy if the field (input).

However, these two values do not relate on thermdynamic grounds. They are seperate systems.
The energy obtained by 'dropping' an object through a small portion of the field is tiny compared to the vast ammounts of electrical energy required to create and sustain an EMF strong enough to move that object.

While in theory, you could drop an infinite number of small objects, covering every point throughout the EM-field, and conserve all of the energy of the field.... This poses mechanical difficulties, which make it impracticle.


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #19 on: August 18, 2010, 01:49:48 AM »

Nope, it won't work. An object is buoyed up by the weight of the fluid
displaced...but to expand an object at depth requires one to lift the
entire weight of the fluid column above it. Fluidics works just like levers.

By the way, I like using a free piston in a cylinder rather than lenticular
metal disks. Vacuum is better than a gas because it has no expansion
coefficients in either pressure or temperature. It makes for easier calcs.
And liquid metal mercury is funner to think about than H2O.



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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #20 on: August 18, 2010, 01:52:54 AM »
The solution to this is to utilize the energy of "static force fields".
These are fields that exist in our environment, which do not require constant energy input to sustain them.

Such fields are:
 permanent magnetic fields, gravitational fields, and buoyant fields.
there are others, but lets just stick to the basics here.

magnetism is not used here, with the exception of motors, which are a well established technology.

The two static fields that are used in the BCG are buoyancy in water (or other fluid), and the earth's gravitational field.


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #21 on: August 19, 2010, 12:54:18 AM »
I just wanna comment the initial ideas in this thread. It will take energy to push the "spheres" of air inside the bottom of the big tank.
Leak of water is just an engeneering problem and cannot be used to deny that this idea will work. If we only focus on the forces step by step in one complete loop it would be seen clearer. The path inside the big tank could also be a sealed plastic membrane, or a very flexible hose (It will be friction, but look away from friction at this point), which alows to freely transform as the spheres rises inside the tank - then the problem of any leak will be solved.

I think however it will not work, but maybe. It will at least take energy to push the spheres the first half way into the bottom of the big tank. You might get free energy provided by the water pressure to push the remaining half sphere into the tank, so hopefully the sum of energy required to completely put the sphere of air inside the tank will be zero. Then the buoyancy effect will take it from there and make an inifinte loop of rotation...

The "spheres" or whatever items used to rise inside the water tank will always be the weight of displaced water lighter than the items that is outside. So these rising items could be made of anything from air to lead - doesnt matter.

I'll make drawings of some ideas that had been interesting to test out.

Try it, it is an interesting idea to explore.



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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #22 on: May 20, 2011, 03:47:56 AM »
I had a similar half baked thought to the original idea of this thread. Putting a pipe with no water straight up and down in it into a tank of water so the buoyancy weight would drop to the bottom using the speed of gravity to allowing it to shoot buoyancy weight out of the air filled pipe. Then somehow have a separate wheel that would capture the buoyant weight to turn the wheel. Then it would need a surface wheel would sweep the buoyancy weight back into the pipe. My original thought was dropping a buoyancy weight down a pipe in water allowing it to shoot out the bottom and it would then float to the surface.   


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #23 on: May 20, 2011, 04:46:59 AM »
lets get something straight, even if you managed to get it right, which you wont, you would have barely enough energy to make it work, you would have little change upon the current power sources. nuclear energy tech alone would rip you a new ass-hole. sometimes you just don't see the full picture.

I am sorry, anyone who plays with more energy than you becomes closer at becoming god like. it is based on how much energy you can play with. I think you need to higher your standards greatly.

you wouldn't want somebody like me to beat you to it would you?

Jerry 8)


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #24 on: May 20, 2011, 04:52:38 AM »
I think if it works even a little it would make a nice novelty item.


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #25 on: May 26, 2011, 07:34:53 AM »
Interesting work. Thanks for sharing it Smokey.

Systems such as the system you propose (using buoyancy and gravity) are fascinating.

I made a modest stab at such a system myself, but abandoned it because the mathematics of the system indicated it could not constitute a useful machine.

Specifically, I once considered using castor oil as a working fluid in two linked tanks (the primary tank containing seawater so essentially buoyancy and gravity as with your invention).

I abandoned the idea because oil was to fall onto a turbine in a mostly empty cylinder, and then float up to the surface of a connected neighbouring cylinder filled with seawater (due to its relatively lower density...961 kg/m3 for castor oil and 1020 kg/m3 for seawater).

However the energy 'gained' through oil floating to the surface of the seawater was 'lost' later on because castor oil (compared to seawater) is a less dense working fluid and therefore the same flow rate provided less Force in Newtons to the turbine.

It all seemed to balance out even before taking into account system inefficiencies and flow rate/viscosity issues, so I abandoned the idea completely.

In passing, I had planned to use compressed air to move castor oil from the turbine tank back into the base of the primary tank where it would float to the surface and be 'siphoned' into the turbine tank.

Turning again to your invention, Low-Q makes an interesting objection that may have traction, namely the idea that work must be done to swing the buoyant objects into the primary tank from beneath. That makes some sense as a candidate objection and I would be most interested in your views on this.

Certainly we must take into account all forces and torques, even forces we may not want to take into account  ;D

Thanks so much for sharing your work.

Interesting and thoughtful.
« Last Edit: May 26, 2011, 08:00:55 AM by quantumtangles »


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #26 on: May 26, 2011, 11:02:24 AM »
ok, we shall now adress the concerns noted during the Reload Phase of the cycle. I have seen mentioned a few times now, the energy requirements to pass the B-unit into the lower portion of the large tank ; this leads me to believe that i was not clear about the state of the device during this phase.

Reload Phase:::

    After all B-units have risen to the top of the bouyancy chamber, generated power on their "rise" and "fall" cycles, and returned to the bottom of the small tank, the B-units are returned to their "0-state".
Meaning, that within the working fluid (water) they are at a state of weightlessness.
This is achieved by depressing the inner solenoid and compressing the halves of the B-unit, such that the verticle bouyant force = 0

Both tank lids are sealed during the reloading phase, therefore the tank pressure is equalized between both large and small tanks, prior to the inner door opening.
With pressure sabalized, the inner door open, and all B-units at their "0-state", the energy required to pass the B-units from the reloading chamber, into their starting position is negligible. There is no resisting force required to move them.

Once the B-units are in place, the inner door is sealed again, and the tank lids are opened - During this stage, as the tank lids are opened the large tank will be at a slightly less-than normal pressure, and "repressurize" to atmospheric pressure. The lower tank will be at a slightly higher than normal pressure, and de-pressurize back to ambient pressure. This is where a small ammount of water is transfered between the two tanks.
This is caused by the compressability of air at the top of the lower tank while the lid is closed, and the inner door opened. (Reload phase)

This takes the system back to the initial "starting" phase.
B-units are at the "0-State", virtual weightlessness.
The first units' solenoid causes the B-unit to expand, becomming bouyant and the generation process begins once again.


So, to clarifiy, there is no significant energy requirements to force the bouyant chambers under the water,
because they are at a zero-bouyancy state during the reloading phase.


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #27 on: May 26, 2011, 06:23:07 PM »
Thanks for explaining the reload phase Smoky.

I would find it easier to understand the reload phase and indeed the entire system if we had a mathematical model.

A hypothetical machine of specified dimensions. This would enable us to calculate all forces acting on the system and also, we would know the power output in watts of the system.

I know comprehensive mathematical models of thermodynamic systems can be difficult to construct, but if you were to provide us with the dimensions (the size of each component), we could have a go at preparing a mathematical model for discussion and analysis.

It is an interesting system and it would be a thousand pities if we failed to examine it carefully using well established equations of motion and fluid dynamics.

So please let us have some system specifications (how big do you want this machine to be) so we can prepare a mathematical model taking into account gravity, buoyancy, viscosity, B unit relative smoothness, temperature, density, air resistance at operating temperature, power output in watts and power input in watts for any parts that require assistance during the power generating cycle.

This is not to say that our mathematical model will be absolutely correct right away (often there are forces one has failed to take into account) but it should be a good starting point for a more detailed analysis of the machine.

Over to you Smoky. Please provide dimensions for your system (simply the size of each component and the materials from which the components are constructed).

For example, water may have various densities in kg/m3. Would you like us to assume it uses fresh water of density 1000 kg/m3 or seawater of density 1020 or 1030 kg/m3?

It can be as big or small as you like, but mathematical focus requires us to have dimensions and materials information.

Thanks for explaining the reload phase of the cycle.

Kind regards,
« Last Edit: May 26, 2011, 07:23:16 PM by quantumtangles »


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #28 on: May 26, 2011, 07:06:54 PM »
By way of example of required specifications, please let me know:

1. The diameter and height in metres of the primary tank and lower vessels.
2. The density in kg/m3 of the water in the primary/lower vessels. Also the flow rate in m3/s of any water lost from the unit (during phase transition) which will have to be replaced.
3. The material from which the B units are made (particularly the density and elasticity of the material) as well as their dimensions when 'inflated' and 'deflated', so we can calculate area in square metres and volume in cubic metres during each phase and the pressure in Pascals (= Newtons per square metre) and therefore the force in Newtons required to 'inflate' them.
4. The precise specifications of the motor powering the robot arm (power consumption in watts, angular velocity in radians per second or RPM, high torque or low torque, stepper motor, conventional motor etc).
5. The material from which the robot arm is manufactured so as to calculate forces applied to the robot arm motor during operation when moving B units and when repositioning itself to move other B units when not under full load. By what mechanism is the inner door opened and closed?
6. The speed in m/s of the B units during their up and down cycles.
7. The materials from which the connecting track (the track on which the B units travel) is made and the dimensions of the connecting track (to calculate weight when in and out of the water).
8. The total length of the track on which the B units will travel.
9. The mechanism by which the B units will be attached to the track on which they travel (eg are there any metal parts whose weight must be taken into account).
10. If the B units travel at different speeds (during the up and down cycles) how is this achieved by way of a single connecting track to which the B units are attached? Is there more than one track, in which event what are the specifications of the second track.
11. If the track is a loop, what is the estimated angular velocity of the loop (or in RPM how many times does the circuit of B units complete a full rotation in one minute?).
11. How is the motive force of the B units transferred to a shaft, pulley or other power transfer mechanism?
12. For the dimensions of the machine you will select, what type of alternator motor would you like to connect to the system (in terms of operating RPM, required torque in N.m and output in kW?

There will be other questions, but this is a preliminary list to give an idea of the information we will need to calculate the power output in watts of the machine.

The power output can then be compared with power consumed by the robot arm motor, air resistance, water resistance, other friction etc to check whether we can make a net gain in energy output (which is the whole point of the machine).

With full disclosure this may be calculated and discussed. If you can only provide some of this information, please provide as much as you can and I will do the calculations based on the information provided and best estimates for the missing parameters.

Kind regards,
« Last Edit: May 26, 2011, 10:12:44 PM by quantumtangles »


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Re: Buoyancy-Based Power Generation - Full Disclosure
« Reply #29 on: May 27, 2011, 02:19:56 AM »
Nicely said QT,

i will do my best to define as many of those things as possible.

The "test unit" B-Units have all been roughly the same
the interior low-pressure chamber has a volume of
~0.07 Cubic Meters - this is based solely on test units, which have been constructed with a set parameter of low-pressure chamber-seals and inner hydraulic cylinders
The exterior size of the B-unit affects its mass, but not its relative bouyancy. The reason for this, is that the working fluid acts directly on the low-pressure chamber by design. This allows for an unrestricted freedom when choosing an exterior housing.

The most promising of these housings, will be composed of 3 layers of hexagon-plates, that interlock in a way that the entire casing becomes smaller as the B-Unit contracts, and becomes larger as it expands. i'll post the info on that as it progresses.

The size and dimensions of the Two tanks are determined by several system requirements, but are completely variable to suit the needs of the system.

There are certain perameters that must be met. The tank lids must seal at or below the specified water level, to minimize water transfer.
and the tank lids and inner door must meet the safety standards of the pressure imparted onto the lower tank when the inner door is opened.

The individual B-units ride along guide-rails that form a track through the system. the top of these rails are disengaged to accomodate the tank sealing. - this action can be a part of the tank-lid closing.

the interface for power generation might take one of several different forms.
a Coil / Magnet interface would allow for direct power generation, or possibly a geared mechanism to drive a rotary generator, connectimg arms that could attach to the B-Units during their entire cycle or at selected times for power generation. There are advantages and disadvantages to each or other approaches, depending on the needs of the system, and each will have its own associated energy costs and electrical production rates.

The phsycal force available, from gravity should be a simple calculation.
the Bouyant force, however, is completely variable, and user defined.

Displacement of the low-pressure chamber is roughly 85% of the ideal state under tap-water, and 82% in air.
giving us an underwater displacement of 0.0595 cubic meters at full expansion.
this may vary slightly with the density of the working fluid.
and potentially increase with technological advancement, such as the aforementioned exterior casing changes.

the inner pressure of the chamber can be calculated by the force to mass ratio that was used to determine the "effective displacement" .
essentially, even though the B-unit takes up more volume,. it is only displacing 0.0595 m^3 of water-mass. if that makes sense....
this is due to the design, that allows the exterior of the low-pressure chanber to "breathe", regardless of the exterior casing design.

even in the flying-hovercraft models, the B-unit still must breathe in this manner for the displaced-mass-bouyancy mechanics to function as intended.

The low-pressure chamber is not a true "vacuum". and the inner pressure is a function of the change in inner volume, and the elasticity of the low-pressure chamber seal. (rubber is used currently)

As far as the function of the opening/closing of the tanks and inner door, these can be the physical operation of the last B-unit during its'  ascent, or decent, or a portion of the energy generated can be used for these functions.

the total power generated will be a function of the bouyancy force used in the b=units, and the height of the large tank.
the height of the small tank is a fuction of the total number of B-units being used, and the space requirements needed to accomodate them.

The B-units will be at a Full-Negative Bouyant State during their descent, and thus gravity has its maximum acceleration force available, dissapated as a function of the downward power generation aperatus and linking mechanism.

To increase the speed and/or power of the upwards generation, you simple raise the B-unit to a higher bouyant state.

The aperatus to move B-units from the smaller chamber to the larger one, while the tanks are sealed (reload), has not been defined yet. But as a comparative example, we could use the stepper motor and arm mechanism found in a commercial Dishwashing Machine (resturant)
although our actual power requirements to move the B-units may be somewhat less than those standards.

The parameters of the actual system, are likely to be defined after selecting the power generation system and linking mechanisms.

from there you can determine your power requirements on the up and down strokes, and well as any additional moving track components that may add more drain  on the system.

from there you can determine the bouyant force required with the given working-fluid, and subsequent Positive-Bouyant-State that you must program the B-unit to change to during the start of the "rise" cycle.

Also, the physical size of the B-unit can be scaled to meet virtualy any requirements.
hovercraft will carry a much larger B-unit than the test models.

the energy available vs the energy required to initiate a bouyant state are two entirely different systems.

Examine the mass of a diver, fully strapped with gear, soaking wet, submerged under 80 feet of ocean water. and how much energy it would require to launch this diver to the surface at ~12 feet per second. This can be easily converted into a value of "displaced mass" needed to accomplish this task.

This value is then used to determine the size of the emergency life-vest, and its associated standard-pressure CO2 cartridge.
now,. compare the energy-value of the CO2 cartridge, to the energy of lifting the diver you just calculated a minute ago....

I understand the importance of hammering out all of the known energy values at each stage of this type of system,
but you must know what values you are attempting to compare.
because just like the diver and his pull-chord vest, that he hopes he never has to use....
The Bouyancy-Based Power Generation technology uses this vast difference in energy to produce a positive gain.
Heres another example, place a rubber-bulbed eyedropped full of air into a plastic bottle full of water and screw on the cap.
now set-up a lever system to push on te side of the bottle with equal force each time.
and you push and the eye dropped sinks, not just sinks, but sinks with force, kerklunk on the bottom.
release the pressure and it shoots up to the top, again with force.

you are pressing lightly and only for a short time, after that you just hold the lever still and it maintains the pressure change in the bottle.

but the eye-dropper is able to produce usable energy both down and up, hitting the bottom with force, and bobbing at the top with force.

plus the pressure in the bottle returns your input energy back through the lever when you release it.

This shows that the two energy systems are not related, although they are interlinked.

one changes the pressure, and thereby the displacement
and the other is the bouyant result of that displacement.

Two entirely different systems. energy in and out does not correlate.


Now with this in mind,. we can select arbitrary dimensions, fluid densities, Generator resistances, ect.
 the mass of the B-unit can be defined as needed, the only restraint is that its mass must correspond to the range of B-states.
meaning the from the  Zero-B-state to the Maximum displacement, within the given fluid pressures. If the total-mass of the B-unit exceeds the displaced mass, it will not reach a Zero-B-State.

Height of the lower tank, number of B-units, ect. will determine maximum system capabilities, but the for calculations, one B-unit will suffice.

physics implies that the linear translation of the B-unit costs no energy, but in practice we must account for water-resistance, gravitational effects of its bouyant-state as friction on the track-rails.
so through the reloading process, as well as the linear-translation necessary at the top of the track, we must account for this as resistance (load) on our robotic arms, this will define the parameters of the motors needed, ect.

to make it simple, you could theorize a 5-volt generation system, that directly drives all the components in the system, the small motors, the controller circuits, any meters, sensors, timers, ect.

energy costs to move, seal, and lock the upper tank lids is a big unknown... there are not many systems like this in use to use as an example. i have seem some that use this principle, but the only one that comes to mind, is an aquatic reserve, that has an upper-pool linked to a lower pool. and to transfer animals from one to another the tanks must be sealed.

theres the weight of the lids, thickness, tensil-strength, ect. and rubber seal? pressurized locking mechanisms??
friction, resistance from the water.. so many unknowns there..

we can start with just defining the outlying parametres and requirements, then build this thing from there, adding / altering each component in the system and its energy drain on the total generating power available to us.