Harnessing energy from gravity

In summary: It's really frustrating when I can't understand what's being said because you are not outputting anything. Just summarize the content.
  • #36
I still find that an utter crock of a statement as by some level of abstraction all energy comes from the sun. Which although true is not really very helpful.

So purely from a practical point of view, all we care about is the gpe of the mass of water has, not how it got it in the first place.
 
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  • #37
Really, it is a matter of where you draw your system boundary, so I wouldn't get too worked-up about either statement.
 
  • #38
xxChrisxx said:
I still find that an utter crock of a statement as by some level of abstraction all energy comes from the sun. Which although true is not really very helpful.

All energy comes from the sun? I think your statement is crock. When nuclear power plants split atoms, this power is coming from the sun? Or is it coming from the mass that big bang somehow put here? was the sun responsible for that mass being "here" in the first place?

Does our electricity that a generator produces come from the magnets then - since they have potential being rubbed off em kind of like how gravity pulls things out of place.

Really, I am just being pedantic and posting statements to create heated arguments.
 
  • #39
physical1 said:
Really, I am just being pedantic and posting statements to create heated arguments.
That's the definition of trolling. Please stop.
 
  • #40
physical1 said:
All energy comes from the sun? I think your statement is crock. When nuclear power plants split atoms, this power is coming from the sun? Or is it coming from the mass that big bang somehow put here? was the sun responsible for that mass being "here" in the first place?

Does our electricity that a generator produces come from the magnets then - since they have potential being rubbed off em kind of like how gravity pulls things out of place.

Really, I am just being pedantic and posting statements to create heated arguments.
Not to feed you or anything but, the most important bit of the statement was "...by some level of abstraction...". So in reality you can keep tracing 'how the energy got there' through some bloody tortuous path to get it back to the sun/universe/whatever. As Russ said where do you draw the boundary.

The point was that from a design point of view that is totally useless to know what the energy has done in the past. Making a machine to harness stored gpe, i'll use the practical and simple notion that yes the energy does indeed come from gravity (gpe) as it is the most convenient starting point for a design.
 
  • #41
What about getting the water up through evaporation/boiling and then harnessing the water flow on the way down?
 
  • #42
technically, neither the sun, nor gravity could do it alone, so we can say neither is directly responsible for the process alone.
but, gravity is the force we are worried about for engineering purposes. we can control getting water to the power plant, but not the force exerted upon it.

dr
 
  • #43
In my mind, the problem to focus on is maximizing the capillary action to pull fluids up through gravity. Then condensing the fluid to harness the flow on the way down. A miniature rain machine.
 
  • #44
it would be better to have a big satellite orbiting Earth and harvesting solar power, and sending it wireless to a receptor, that would distribute electricity to the Earth homes...

i think electrity companies donnt want that of course to happen. free energy EHEH noo..
 
  • #45
MiguelQ said:
it would be better to have a big satellite orbiting Earth and harvesting solar power, and sending it wireless to a receptor, that would distribute electricity to the Earth homes...

i think electrity companies donnt want that of course to happen. free energy EHEH noo..

Is that possible? Not a bad idea.

However, I do have a business plan for utility and oil companies that will work with this energy machine. Both types of companies will be very profitable.

Here's the idea in a nutshell:
- intramolecular forces are the root of thermal motion and kinetic theory
- strength of intramolecular forces is a function of temperature
- fluids leveraging natural evaporation/condensation will carry water up against gravity
- harnessing energy from gravity is then possible

This in no way is a perpetual energy machine nor does it break any laws of thermodynamics. With respect to thermodynamics, gravity is frequently ignored in most analyses of kinetic energy.
 
  • #46
andrewbb said:
What about getting the water up through evaporation/boiling and then harnessing the water flow on the way down?
Because of the first law of thermodynamics. It would consume energy to evaporate/boil the water. You could never get more energy out then what is put in. It's easiest to let the sun to the evaporating.

andrewbb said:
In my mind, the problem to focus on is maximizing the capillary action to pull fluids up through gravity. Then condensing the fluid to harness the flow on the way down. A miniature rain machine.
It would take energy to remove the water from the top of the capillary tube.

To paraphrase Homer Simpson: "In this forum, we obey the laws of thermodynamics."
 
  • #47
Redbelly98 said:
Because of the first law of thermodynamics. It would consume energy to evaporate/boil the water. You could never get more energy out then what is put in. It's easiest to let the sun to the evaporating.

It would take energy to remove the water from the top of the capillary tube.

To paraphrase Homer Simpson: "In this forum, we obey the laws of thermodynamics."

The energy to condense water comes from intramolecular forces (hydrogen bonding).

Removing the water from the top of the capillary tube is performed by gravity.

Don't forget about the force of gravity in perceived thermodynamic limitations.

Consider: increasing the condensation rate of water vapor by electrifying a condensation rod. That uses a very slight amount of energy and leverages already existing intramolecular forces (hydrogen bonding). Once a water droplet forms, gravity pulls it off that rod. Imagine that water droplet accelerating as it falls 20m. The energy in that moving water droplet is greater than the tiny current required to attract a few water molecules out of the air. With some intelligent choice of materials (maybe silver iodide) that leverage the pre-existing hydrogen bonding tendencies of water and you wouldn't even require a current.
 
  • #48
Redbelly98 said:
Because of the first law of thermodynamics. It would consume energy to evaporate/boil the water. You could never get more energy out then what is put in. It's easiest to let the sun to the evaporating.

It seems to me that people constantly confuse 'free energy' that breaks the laws of thermodynamics, and energy that costs nowt. (ie is 'free')
 
  • #49
xxChrisxx said:
It seems to me that people constantly confuse 'free energy' that breaks the laws of thermodynamics, and energy that costs nowt. (ie is 'free')
Yes, perhaps I was misunderstanding what was being said/meant earlier.

andrewbb said:
The energy to condense water comes from intramolecular forces (hydrogen bonding).

Removing the water from the top of the capillary tube is performed by gravity.
Here is my problem with that: if the force drawing the water into the capillary is stronger than gravity, then gravity is too weak to remove the water from the tube. And if the capillary force is weaker, then the water will not move up the tube in the first place.

Don't forget about the force of gravity in perceived thermodynamic limitations.

Consider: increasing the condensation rate of water vapor by electrifying a condensation rod. That uses a very slight amount of energy and leverages already existing intramolecular forces (hydrogen bonding). Once a water droplet forms, gravity pulls it off that rod. Imagine that water droplet accelerating as it falls 20m. The energy in that moving water droplet is greater than the tiny current required to attract a few water molecules out of the air. With some intelligent choice of materials (maybe silver iodide) that leverage the pre-existing hydrogen bonding tendencies of water and you wouldn't even require a current.
I have never heard of doing this. Do you have any references, or a link showing an actual working demonstration of this? Also, does "electrifying" mean applying a voltage & creating an electric field, or passing a current through the rod, or something else?
 
  • #50
Redbelly98 said:
Here is my problem with that: if the force drawing the water into the capillary is stronger than gravity, then gravity is too weak to remove the water from the tube. And if the capillary force is weaker, then the water will not move up the tube in the first place.

Capillary force is determined by the electromagnetic charges of the molecules. Different molecules have different strengths, so you could have a 2 material tube. Strong at first that pulls up, slope down on the weaker strength tube and gravity will overcome the cohesion.


Redbelly98 said:
I have never heard of doing this. Do you have any references, or a link showing an actual working demonstration of this? Also, does "electrifying" mean applying a voltage & creating an electric field, or passing a current through the rod, or something else?

No references. It's an idea I had about 4 weeks ago and am researching now. Given that hydrogen bonds are essentially a magnet, this seems doable. FYI, I do consider hydrogen bonds as the same force governing "capillary action". Just on the molecular level.
 
  • #51
andrewbb said:
Capillary force is determined by the electromagnetic charges of the molecules. Different molecules have different strengths, so you could have a 2 material tube. Strong at first that pulls up, slope down on the weaker strength tube and gravity will overcome the cohesion.

No references. It's an idea I had about 4 weeks ago and am researching now. Given that hydrogen bonds are essentially a magnet, this seems doable. FYI, I do consider hydrogen bonds as the same force governing "capillary action". Just on the molecular level.

I really mean no offence by this but... what utter crap.

The single biggest overriding factor that governs capillary action is having a very narrow tube and the relative pressures at either end.

Water isn't attracted by 'magnets' like you are thinking becuse it has a dipole, the attraction has to be induced and water has extremely low permeability. (Ie it doesn't magenetise well.)There is much much more interesting (similar) thing being done like this already. It uses a membrane and salt and fresh water. Due to the different concentrations the water crosses the membrane by osmosis raising the levels and forcing the water up and through a nozzle that drives a turbine.

Only really any good if you live next to a river and the sea but, it's pretty cool.
http://news.bbc.co.uk/1/hi/world/europe/8377186.stm
I'm trying to find the video I saw of it.
 
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  • #52
andrewbb said:
Capillary force is determined by the electromagnetic charges of the molecules. Different molecules have different strengths, so you could have a 2 material tube. Strong at first that pulls up, slope down on the weaker strength tube and gravity will overcome the cohesion.
Where gravity overcomes the capillary force, the water will stop rising in the tube. It won't make it to the top.
No references. It's an idea I had about 4 weeks ago and am researching now. Given that hydrogen bonds are essentially a magnet, this seems doable. FYI, I do consider hydrogen bonds as the same force governing "capillary action". Just on the molecular level.
Hydrogen bonds are not "essentially a magnet", they are electrostatic in nature.

To put things nicely but honestly, it sounds like you do not actually understand the science behind what you are proposing.
 
  • #53
Um... what do you think "dipole" and "electrostatic" are? They are forms of ELECTROMAGNETISM.

Why do you think water molecules form hydrogen bonds? The negative charge of the O is attracted to the positive charge in the H. That's essentially a magnet my friends.

Why is water attracted to its glass container? Well.. take a look at the structure of a molecule of glass. Lots of H's my friends. What is attracted to those H's? Why that would be the O's in the water molecules.

Why does water evaporate most quickly in butane? Again... take a look at a butane molecule. A few C's surrounded by a bunch of H's. What is attracted to those H's? Well a bunch of O's in water molecules.

It is YOU that doesn't understand the science. Why don't YOU explain water cohesion and its attraction to glass? If you use "dipole" or "electrostatic", please look up the words first.
 
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  • #54
andrewbb said:
Um... what do you think "dipole" and "electrostatic" are? They are forms of ELECTROMAGNETISM.

Why do you think water molecules form hydrogen bonds? The negative charge of the O is attracted to the positive charge in the H. That's essentially a magnet my friends.

'Essentially' a magnet. Do you know what permeability is? Water has a similar permeability to air and aluminium. They don't respond to regular strength magnets, and neither does water.
 
  • #55
xxChrisxx said:
'Essentially' a magnet. Do you know what permeability is? Water has a similar permeability to air and aluminium. They don't respond to regular strength magnets, and neither does water.

Individual molecules act as tiny magnets with each other, but the effect is not additive across chains of hydrogen-bonded molecules.

EDIT: water molecules are affected by electromagnetic fields. EG. microwaves will spin the molecules.
 
  • #56
andrewbb said:
Why is water attracted to its glass container? Well.. take a look at the structure of a molecule of glass. Lots of H's my friends. What is attracted to those H's? Why that would be the O's in the water molecules.

Why does water evaporate most quickly in butane? Again... take a look at a butane molecule. A few C's surrounded by a bunch of H's. What is attracted to those H's? Well a bunch of O's in water molecules.
Did you learn this chemistry in school or are you going on your own deductions?
 
  • #57
andrewbb said:
Individual molecules act as tiny magnets with each other, but the effect is not additive across chains of hydrogen-bonded molecules.

EDIT: water molecules are affected by electromagnetic fields. EG. microwaves will spin the molecules.

This is all just mental masturbation. You try to 'suck' water up using a magnetic field it WILL fail. Water just doesn't magnetise, that is really as simple as it gets. You can use magnets to polarise molecules (a la NMR machines), but this is a very far cry from acutally moving molecules with them.

Applying a strong magnetic field does have a very small effect on the surface tension. By stong I mean on the order of 100000's gauss to give small percentage changes in surface tension.

Top marks for creative thinking. However like all things, creative thinking and pratical useage are worlds apart.
 
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  • #58
xxChrisxx said:
This is all just mental masturbation. You try to 'suck' water up using a magnetic field it WILL fail. Water just doesn't magnetise, that is really as simple as it gets. You can use magnets to polarise molecules (a la NMR machines), but this is a very far cry from acutally moving molecules with them.

Top marks for creative thinking. However like all things, creative thinking and pratical useage are worlds apart.

I agree. You won't suck up water using magnetism. But individual molecules do respond to electrical charge.

The strength of the charge of a single molecule is a function of where the electrons are in relation to the protons. On water, the hydrogen atoms' electrons are covalently bonded to the Oxygen so the Hydrogen's protons' positive charge is exposed. Since there are 2 un-bonded electrons on the Oxygen, that side is negatively charged and can attract the Hydrogen side of another water molecule. That attraction is electromagnetic, but the effect is certainly not additive, so hydrogen-bonded water molecules are not going to form a magnet.

At high temperatures, the above is not a huge effect because hydrogen bonds are weakened, however at room temperatures, this effect is important. I am trying to find ways to accelerate condensation of water vapor at room temperature.
 
  • #59
look water is magnetized like matter is.. just check those videos on youtube with high power magnets and you will se water foating like zero-G
 
  • #60
and we all know no one fakes stuff on utube
like the cell phone popcorn thing
somehow the idea of a magnet that strong brings the image to mind of the coyote road runner cartoons, where the coyote shallows the magnet, then everything magnetic comes chasing after him

dr
 
  • #61
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  • #62
Erazman said:
Theres already methods of harnessing energy from gravity (like from the flow of water), but not in very massive amounts.

The highest capacity power plant in the world is the Three Gorges complex currently above 20,000 MW of hydroelectric power.

The water mass of the complex is so great that it has bent the Earth's crust.
 
  • #63
thats from its mass, not its magnetism

dr
 
  • #64
Redbelly98 said:
Water's relative permeability, according to http://en.wikipedia.org/wiki/Permeability_(electromagnetism)#Values_for_some_common_materials", is only μ/μ0=0.999992

If you're going to make fantastic claims, at least post a link to "those videos" so we have something to critique.

He's going to link the levetating frog. Not realising that it's BECAUSE water has a low permeability (ie it's a diamagnet) that it levetates which isn't the same as magnetising it. It also required enormous field strengths.On a different note, I believe I misread what andrewbb was talking about (just reread the thread). The talk of capillary action made me thing he was trying to increase that effect by magnetism :redface:. Not that just a charged rod would encourage condenstation. Which I've never head of, but don't know enough about to comment.
 
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