Sciencemadness Discussion Board

Free energy Idea, need thoughts

ThoughtsIControl - 15-5-2020 at 12:43

I had a dream where I made free energy. The simplistic idea goes like this..

Perform electrolysis on water. Have the hydrogen and oxygen led to separate, narrow tubes filled with water. Oxygen and hydrogen obviously rise. These gases condense at a height (h) and then fall back to earth the energy is captured from the fall. The water is then electrolyzed again. Here's where my idea comes in..

The higher that the transport tubes extend upwards, the more force that a mole of water falling back down will exert.

This continuous process could theoretically produce more energy than is required to split the hydrogen and oxygen DEPENDING ON the height of the transport tubes. The longer that the water falls, the force gets multiplied by 9.8m/sec (gravity).

MY QUESTION: At what height of the transport tubes (h) will cause me to have enough force to get more energy out than I put in during the process of electrolyzing a mole of water.

PS. I am unaware of how efficiently I could capture the energy of falling water, and that's the problem I'm having.

[Edited on 15-5-2020 by ThoughtsIControl]

Fulmen - 15-5-2020 at 12:54

Son, let me put this as gently as possible: You're so far off you're not even wrong. You're just.... *sigh* ....

There is no such thing as a free lunch. Not in life, nor in physics. Not ever.
These are them rules, deal with it.

karlos³ - 15-5-2020 at 13:00

TINSTAAFL, as Fulmen said :D
Heinlein is great stuff.

Refinery - 15-5-2020 at 13:18

Lol. These perpetual motion concepts are always hilarious. People try to cut the margin so small that "there must be energy created out of nowhere".

It could actually appear so, because the system gets energy from outside. If you make tubings and lead potential into somewhere, it is likely to get thermal energy from the structure, that originates from the surrounding environment, and hence it looks like free energy. Utilizing this energy.. Better just get a solar panel, wind turbine, water turbine, grow plants and use the biomass produced, etc.

If there was "sloppy" energy, it is to be found in nuclear or quantum forms. It was otherworldly question that a gram of fissile material can deliver energy worth 100 tons of crude oil, and was it pure annihilation, it would be 10 times that, at least. Sure, in the future, someone figures out how to rip or fuse quantum particles or even sub-quantum particles, and then we get to another order of magnitude of energy. Though they'll most likely weaponize it first and threat to blow up the whole planet before someone figures it could be used to make actual usable energy.

But not from your gas tubings. Sorry. :D

clearly_not_atara - 15-5-2020 at 13:32

Water electrolysis is extremely lossy in terms of hydrogen production due to Joule heating. It's not even close to reversible.

That's before we get in to the whole "perpetual motion is impossible" thing. Any idea that begins with the electrolysis of water is no good for anything unless the goal is to produce ozone.

[Edited on 15-5-2020 by clearly_not_atara]

Fulmen - 15-5-2020 at 13:45

House rules:
Heads: I win
Tails: You loose

clearly_not_atara - 15-5-2020 at 15:02

Quote: Originally posted by Fulmen  
House rules:
Heads: I win
Tails: You loose
thermodynamics in a nutshell lmao

arkoma - 15-5-2020 at 15:08

Quote: Originally posted by karlos³  
TINSTAAFL, as Fulmen said :D
Heinlein is great stuff.


TANSTAAFL mate. The Moon is a Harsh Mistress

Syn the Sizer - 15-5-2020 at 15:20

I know a few people who have had perpetual energy ideas. One of the biggest thing people forget is the friction of air. Even if you remove every other source of friction there is still air. I agree perpetual motion/energy is a perpetual pipe dream.

Chemetix - 15-5-2020 at 16:19

Free energy thoughts are deliciously fun mind games to play, don't stop dreaming of ways to cheat the system because it's a good way to learn, REALLY learn the interactions of the physics concepts at work. It can lead to deep understanding and masterful use of engineering. Free energy is slightly different to perpetual motion, solar panels or wind turbines are a way of getting free energy if the economics of the endevour is properly accounted for.

I love good Sci-Fi and free energy/perpetual motion ideas can sometimes be really close to the real world, it makes total immersion into the idea believable.

Keep your head in the clouds but feet on the ground.

Johnny Windchimes - 15-5-2020 at 16:52

There is a reason it's not called the 1st Suggestion of Thermodynamics....

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

draculic acid69 - 15-5-2020 at 18:25

U want free energy? Buy solar panels.

UC235 - 15-5-2020 at 20:13

OP's name calls to mind an oft-banned troll that I thought we were rid of.

G-Coupled - 16-5-2020 at 03:52

Quote: Originally posted by UC235  
OP's name calls to mind an oft-banned troll that I thought we were rid of.


Hmm - more hint please, if possible?

j_sum1 - 16-5-2020 at 03:59

Quote: Originally posted by G-Coupled  
Quote: Originally posted by UC235  
OP's name calls to mind an oft-banned troll that I thought we were rid of.


Hmm - more hint please, if possible?


Does not seem a likely hypothesis. And in any case we can afford to give the benefit of doubt.

And if you don't know of whom we refer, that's a good thing. It is nice to have the place free of trolls.

Vomaturge - 16-5-2020 at 06:00

Quote: Originally posted by ThoughtsIControl  

MY QUESTION: At what height of the transport tubes (h) will cause me to have enough force to get more energy out than I put in during the process of electrolyzing a mole of water.


it takes an absolute minimum of 285kj to break up a mole of water (18 gm, more or less.) if you had perfect efficiency, you could get 1 joule of energy out of an 18 gm mass descending 5.66 meters. So the tube would have to be 1,614 kilometers tall for this idea to work, actually taller because gravity gets weaker the higher you go. Assuming the water was incompressible so its density was constant, the pressure from that water column would be 161,400 kgf/cm2 or 158kBar. This may just happen to be the pressure where a 2:1 mixture of oxygen and hydrogen has the same density as H2O.

So that's the answer. It takes the same amount of energy to raise water 1614km, as it does to electrolyze it. I still don't think we will get free energy out of it, but where does the energy go?

I've heard about high pressure electrolysis cells which were designed to feed a high pressure storage system without any compressor. Supposedly that saved the energy needed to compress the gas with an external compressor. I'm not sure where that energy comes from but I suspect that a cubic meter of ideal gas at 1 atmosphere and room temperature has the same internal heat energy in it as a liter of the same ideal gas at the same temperature and 1000 atmospheres. The difference is one has less entropy, so it's possible to use the normal heat energy in it and even use heat energy from the environment. But theres still no free energy. It takes a flow and a waste of energy to even get a gas into a high presure state, even if it doesn't add any internal energy to it.

In the case of electrolysis, we can keep tracing energy and entropy back and find out that anything that splits a mole of water into its separate components must have dissipated a lot more than 285kj in the process of spliting that water. So, if it was energized with a coal fired boiler, maybe it took a megajoule of heat energy to generate enough power to electrolysis a mole of water.

sodium_stearate - 16-5-2020 at 06:16

Right. Except there's this little thing called entropy.

If you want a free lunch, go to the soup kitchen.

But then as you consume your "free" soup, just
remember that it's not really free at all. It was paid for
by working people who pay taxes. It was made by
volunteers who work there from the paid-for ingredients.

Thermodynamics says "There aint no free lunch!"

Free energy? Perpetual Motion? Those are universal things
which just never seem to go away. Just the same as
Doctor Hoekey Poekey's miracle cure which contains 80%
alcohol.

It's all easy money to be extracted from easily manipulated
souls.

ThoughtsIControl - 16-5-2020 at 06:45

Thank you all for your comments.
I understand all the laws, and as an undergraduate student I felt more comfortable questioning things on this platform rather than asking a teacher.
I guess it must be true that you can’t get a free lunch out of nothing.. damn because I’m starving.
Also, those that are saying my name is similar to an older member that was banned -
My name is derived from something I learned from Zen meditation. You feel the way you think, I control the way I feel

Vomaturge - 16-5-2020 at 06:54

Umm...
Quote: Originally posted by Vomaturge  
I...'m not sure where that energy comes from but I suspect that a cubic meter of ideal gas at 1 atmosphere and room temperature has the same internal heat energy in it as a liter of the same ideal gas at the same temperature and 1000 atmospheres. The difference is one has less entropy, so it's possible to use the normal heat energy in it and even use heat energy from the environment. But theres still no free energy. It takes a flow and a waste of energy to even get a gas into a high presure state, even if it doesn't add any internal energy to it.

In the case of electrolysis, we can keep tracing energy and entropy back and find out that anything that splits a mole of water into its separate components must have dissipated a lot more than 285kj in the process of spliting that water. So, if it was energized with a coal fired boiler, maybe it took a megajoule of heat energy to generate enough power to electrolysis a mole of water.


Yeah, I'm aware of entropy. I'm aware that its one of the things preventing free energy. I'm also aware that the OP is likely the troll who initially used the username "phdChemist." But these discussions are worth having. If you can't figure out *where* exactly, the the "free energy machine" will run out of power, people will keep thinking they've found a loophole. Also, it doesn't hurt to examine how thermodynamic rules apply to something like this. It's a great way to learn how to apply them to practical engineering problems.

Edit: I was writing this reply to sodium stearate, and didn't realize thoughtsIcontrol had replied in the mean time.

[Edited on 16-5-2020 by Vomaturge]

ThoughtsIControl - 16-5-2020 at 07:11

As I said in a previous comment, and this is the last time I’ll mention it.
I am not a troll who has used this platform before. I’m a freshman In college in the US that has a newfound passion for chemistry.
I just want to learn. I apologize if my question posted in “beginnings” seems as if I’m trolling to some of you. I’m a smart kid who doesn’t know all the rules to the game of chemistry just yet.

I’m sure it’s a question that you guys have had run through your head at a point. My reason for posting this was to get a reply such as the one from Vomaturge on the mathematics for a theoretical.

Anyway, to keep the thread alive:

Are there any crazy free energy ideas you guys have heard of that youd like to share?

mayko - 16-5-2020 at 10:39

Quote: Originally posted by Chemetix  
Free energy thoughts are deliciously fun mind games to play, don't stop dreaming of ways to cheat the system because it's a good way to learn, REALLY learn the interactions of the physics concepts at work.


Yes! Maxwell and his Demon are a famous example. When I was in high school, I went through a heavy perpetual motion/overunity phase, not because I didn't understand or accept thermodynamics, but because I could learn more about lunches, by figuring out where my apparent free lunches were disappearing to.

One of my favorites was a siphon which would draw oil off of an upper layer in a tank of oil and water, into a lower tank. This one has a pipe connected to the bottom of the first tank, such that oil rises back up through the water, turning a paddle wheel on the way before returning to the upper layer. I couldn't figure out the breakdown for the longest time, until my (very patient) shop teacher asked me: How are you going to keep water from flowing back out the bottom pipe and filling the second, lower tank?

No matter how I wriggled, I couldn't dream up a passive way to keep this from happening, or to return the water to the first tank. After trying and trying, it struck me: For a volume of oil to rise, an equal volume of denser water must fall, and there's no getting around it. *Full Metal Alchemist Theme plays*

SWIM - 16-5-2020 at 16:20



This gas you generate is less dense than the water, so it rises, but that also means when it is produced it takes up more space than the water it was made from, so it lifts the entire 1670 meter column of water above it before it rises through the column allowing all that water to settle back where it was.

Wouldn't that be happening with every bubble?

Where does that energy come from?

I'm not asking this for didactic purposes, I really don't know if this means water under great pressure takes more energy to split into component gases, and perhaps even more if its in a really long vertical tube.

EDIT: If you just have a 1670 meter high tube for the hydrogen gas, and burn it at the top to get water it'll give you the same result in terms of water at an altitude with fewer complications.
Not that it'll give you free energy. of course, but it will cost less to set up.

[Edited on 17-5-2020 by SWIM]

Did I miss where we try to also catch the energy released at the top when we burn the hydrogen gas?
Every little bit helps.

And if you're burning the Hydrogen up there with atmospheric oxygen then the oxygen made by the Hoffman apparatus down on the ground is available as a byproduct.

Yes, I realize this still must not work.
But pointless engineering refinements can be fun.

Hey, instead of that hard to build 1670 meter high tube how about the burner for the hydrogen at ground level and the Hoffman apparatus at the bottom of a disused oil well?

Or South African gold mine? I believe they also get that deep.

[Edited on 17-5-2020 by SWIM]

Vomaturge - 16-5-2020 at 20:41

I don't know that electrolysis at the bottom of a high water column actually takes more energy. Half a mol of 50C air floating through the inside of a warm running computer should have the same internal energy as half a mol of 50C air confined inside an old wine bottle. But the latter has less entropy, meaning it's in a good position to convert its internal energy into kinetic energy, all while suddenly, drastically, lowering its own temperature.

What does that have to do with electrolysis? Well, if we electrolysed a mol of water without letting the gases expand, we might have a hope of getting back the 285kj of potential energy we gave them, at least in theory. But if we let the gases expand, in order to form a bubble against atmospheric pressure, or displace a water column, etc, now the gases are in a high entropy state and theres no way we can ever get anything close to as much energy out as we put in. If they ignite, they will expand more, but their pressure will equalize with atmospheric long before they have cooled to room temperature. The remaining heat energy can't really be salvaged.

In the initial idea we have a water column tall enough that a mol of water descending releases the same energy as it takes to electrolyse it. Thats not 1600 meters, but 1600 kilometers tall. The pressure at the bottom is 158kbar, several times the pressure used to convert graphite to diamond, and similar to what you'd get inside a dense solid "energetic material" if you set it off in a tight fitting infinitely strong container that didn't let the gases cool or expand at all. So in this case,chances are the water electrolyses, but the pressure is so severe, the hydrogen and oxygen don't expand. They don't gain entropy, but they don't displace any surrounding water either. They just pool in the water like another liquid, and slowly dissolve and difuse into the water.

That's my prediction. But I'm such a n00b when it comes to thermodynamics that I'm probably missing some key points.

j_sum1 - 16-5-2020 at 21:52

Don't forget the matter of nucleating and growing a bubble of gas. That will be higher in a high pressure liquid.

That fact alone will eliminate any gains you might get through deep electrolysis.

This seems to me to be one of the least viable perpetual energy designs. Worse than marginal as soon as you mention electrolysis. Then apparently 1600 vertical km of tubing to take advantage of a gravitational force field. And all that is before considering frictional effects and heat losses.
I think you would be lucky to get single digit percentage recovery of the energy you put in.

wg48temp9 - 17-5-2020 at 00:02

Initially I was unable to get the sums correct and balance but I think I have it now.

There is an electrolysis overvoltage caused by pressure. That over voltage must supply sufficient energy (via compression) to rise the hydrogen and oxygen through a column of water of sufficient height such that its increase in gravitational potential energy is equal to the enthalpy of formation of water.

So ignoring inefficiencies and compression problems the electrolysis must supply twice the energy required to split the water, half will be returned when the hydrogen oxygen burn and half when the resulting water returns to the start height. Absolute maximum efficiency 50% no over unity and no free lunches.

brubei - 17-5-2020 at 00:06

In a simple way to understand your problem

If a falling droplet have more energy than the same quantity of energy to break the chemical bonds of all the molecule inside, the impact of your droplet on your rotor would be devastating.

SWIM - 17-5-2020 at 19:08

Okay, kilometers, not meters.

Can't believe I missed that.

@wg48temp9: Holy crap!

Some of that actually made sense?

I was mostly posting because I'd had too many espressos.