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Home: Electricity: Power Outlet
groundless electricity   (+3, -12)  [vote for, against]

A normal electric circuit has an active wire and a ground wire. Electricity flows from the active wire through the load (i.e. an appliance) and back through the ground wire.

I'm wondering what would happen if you got rid of the ground wire.

In this scheme the active wire carries an alternating voltage. The alternating voltage is split (rectified) into a positive and negative DC component. The load is placed across the positive and negative DC component. (see illustration)

problems: without a ground as reference voltage the appliance could build up a dangerous charge. I'm thinking this could be overcome with simple electronic design that recognises that ground is half-way between the top and bottom of the AC signal.

advantages: In situations where a single wire is more convenient than two wire. Admittedly there aren't many situations where this is the case, except perhaps at the very small scale (I thought this up when pondering another idea of mine - modular neural network).
-- xaviergisz, May 10 2007

illustration http://imgur.com/a/pEIJC
groundless electronics [xaviergisz, May 10 2007, last modified Dec 12 2011]

Ohms Law http://en.wikipedia.org/wiki/Ohm's_law
[jhomrighaus, May 10 2007]

Kirchoff's plumbing laws http://en.wikipedia...ff%27s_circuit_laws
Gotta have a circuit... [Jinbish, May 10 2007]

US 6,104,107 http://patft.uspto....04107&RS=PN/6104107
Method and apparatus for single line electrical transmission [xaviergisz, May 10 2007]

Avramenko one wire circuit http://jnaudin.free...amenko/avramenk.htm
identical circuit to mine (and no, I didn't copy) [xaviergisz, May 10 2007]

some more info supporting my comments. http://www.answers....e-transmission-line
[jhomrighaus, May 11 2007]

US 2005/0173990 http://v3.espacenet...DX=US2005173990&F=0
One wire self referencing circuits for providing power and data [xaviergisz, May 11 2007]

Capacitance http://en.wikipedia.org/wiki/Capacitance
See esp. "self" and "stray." [csea, Jul 27 2008]

AC/DC concurrently?
-- nuclear hobo, May 10 2007


This will not work, you need to have a circuit to allow current to flow. with no ground there is no current in the hot wire, there is electrical potential but no current. In an AC system it is not just a sift from positive to negative but an actual change in the flow direction of the current. Polarity does not equal ability to do work. You need to have current for anything to happen.

your circuit diagram is effectively a wire, if tested the potential across the leads there would be nothing there.

When your upper lead is seeing + the lower lead is seeing nothing at all(lack of ground no current flow) as the diode is blocking the incoming + flow, when the switch occurs the bottom will see - but the top will see nothing as it has only negative to draw from(which again is blocked by the diode).

This just does not do anything and is very clearly bad electronics and physics and science to.
-- jhomrighaus, May 10 2007


hmm, ok jhom.

I thought if you can transfer power wirelessly, power transfer with one wire would be a cinch.

I've edited to remove reference to alternating current and replaced with alternating voltage.

I'll leave the idea up as a punching bag for people to show their physics/electronics prowess.
-- xaviergisz, May 10 2007


Well, I guess I'll take a swing.

As I understand it, electrical circuits have three wires. Two for AC, and one for ground, on which electricity will only flow in the event of some emergency or accident.

That said, I think you might want to examine some of the writings of Tesla. He seems to have come up with some sort of single wire applications that worked for lighting. I can't quite wrap my electrically feeble brain around it, but then again, I've only recently come to accept that the wire is indeed solid, and not some sort of tiny pipeline.
-- ye_river_xiv, May 10 2007


Nope Cant do that either. Current Voltage and Resistance(load) are inextricably linked to each other. Cant have one without the other 2.

I(Current)= V(voltage)/R(resistance)

This is Ohms Law, one of the fundamental laws governing electrical Circuits.(see link)

Actually [ye_river_xiv] looking at wires as little pipes actually can aid in understanding the operation of an electrical circuit. In this case imagining a pipe with a y in it an a set of check valves positioned on each one, facing opposite directions. If you then connect the ends of these 2 arms of the Y to represent the DC portion of the system and include a small turbine that only makes power when the water flows from top to bottom, you will then be able to represent the system very accurately.

Connect a Sliding piston to the other end of the pipe so that when the piston is moving away you would get - or lower presure flowing right to left and when it is moving to the right you get positive pressure flowing left to right.

What happens to various parts of the system as you move the piston, First the pressure in the pipe before the Y will first increase and then decrease, second the pressure at the top check valve(+) will increase same as with the lower valve, at the turbine the same thing happens, then as the piston moves away the reverse will occur and all the pressures will fall. What does not happen in this system is water flowing in any way. If you assume perfect materials(no expansion etc) then the Piston will be unable to move(cant compress the fluid, pipe doesnt expand) so nothing can change the system is static. Only when you open the pipe(connect the system to ground) can the water(current) flow. The amount of pressure applied to the piston represents the Voltage and the size of the hole at the end of the pipe represents resistance.

Sorry [xaviergiz] but your idea does not work because it is fundamentally flawed.
-- jhomrighaus, May 10 2007


OK, the particular schematic I have shown might not work, but are you saying that power transfer with a single wire is impossible?

Normal wireless power systems use the magnetic field produced by an alternating current.

I'm suggesting using the electric field produced by an alternating voltage to transmit power.

I don't see the fundamental flaw in this reasoning.
-- xaviergisz, May 10 2007


I'm fairly sure you could transmit energy this way, but at low voltages and frequencies the power would be miniscule. If you could achieve an RMS charge of one coulomb at 50 Hz, 240V, the power would be 12 KW (I think), but one coulomb is a truly colossal charge.

From Wikipedia: "If two point charges of + 1 C are held one meter away from each other, the repulsive force they will feel is given by Coulomb's Law as 8.988×109 N [1]. This is roughly equal to the gravitational force of 900,000 metric tons of mass at the surface of the Earth; in everyday terms, it's enough force to accelerate an Airbus A380 airplane up to a final speed of 76,857 km/h in 1 second."

The signal from a single wire antenna gets into a battery powered radio reciever in this way, but the frequency is high (RF) and the power extremely small.
-- spidermother, May 10 2007


// but are you saying that power transfer with a single wire is impossible?//

Power transfer through radio waves is not(as was pointed out) But neither is this power transfer through a single wire it is field generation which is a completely different process than current flow(AC or DC)(though is closely related)

As you presented and illustrated this idea is impossible. If you are talking about generating an RF field then that is essentially an antenna and that is not a new idea and you are not proposing anything new(incidentally what you described is not an antenna or an RF generator of any type)

As I read your idea you propose to take a single hot lead out of a electrical outlet(there are three, Hot Neutral and ground) Attach a couple of diodes then connect an LED between them. I posit that such an apparatus will do nothing at all. There will however be a weak electromagntic field surrounding the wire but this will not do anything to make the LED light up.

//Normal wireless power systems use the magnetic field produced by an alternating current.//

Your right they do do this, BUT both sides of the system (transmitter and receiver) are constructed of a Circuit which has a neutral connection. The energy transfer occurs through Magnetic induction but again you can only generate or utilize that field through completed circuit on both sides. YOU CANNOT HAVE CURRENT WITHOUT CLOSING THE CIRCUIT!

If you are now talking about radio or magnetic power transmission then your idea needs to be seriously revised as that is not what it is discussing.
-- jhomrighaus, May 10 2007


There aren't any LEDs in the illustration, just two diodes and a capacitor. I haven't shown the load, but that would be connected across the '+ DC' and '- DC' outputs.

you're right, I'm not talking about transmission by electromagnetic waves, I'm talking about transmission by an electric field.

//both sides of the system [normal wireless power system] (transmitter and receiver) are constructed of a Circuit which has a neutral connection//

do you mean the receiver of a normal wireless power transmission systems must be attached to ground to work? I'm pretty sure this is not the case.
-- xaviergisz, May 10 2007


no I'm saying that the receiver must be a complete circuit(within itself) to work.
-- jhomrighaus, May 10 2007


Ok, I'll take a different approach.

I don't have a power input and output wires. Instead I've got a single wire that acts as an input at one moment in time and an output at another moment.

do you need an input and output wire simultaneously or can you suffice with one wire that acts alternately as both?
-- xaviergisz, May 10 2007


I've worked with electrickery for about 35 years and, every now and then, an idea comes along that completely undermines the fundamental model that I hold in my head of how this tricky stuff works.

Sorry; this isn't one of them. One wire transfer of electrical power requires capacitance for storage and, finally, some kind of load for extracting power from the flow, as well as 'extremely' high voltages. As [spidermother] mentions, the capacitance requirement is rather large. A normal capacitor cannot be used, since it requires two connections.

You have effectively invented 'static' charge.
-- Ling, May 10 2007


Hold on. I may be spectacularly wrong here, but this is how national power grids already work (ie, single-wire).

My understanding is that overhead (or buried) cables are just the "live" side of the circuit - the earth provides the return route. Both the power station and the local substations are "earthed" (ie, they share the earth as a common neutral).

From the local substation, you have both live and neutral ("substation earth") wires for the last leg of the journey. You also have a local earth (the "ground wire" as it is normally thought of) connected to the ground at your house.
-- MaxwellBuchanan, May 10 2007


erm, as I remember it, the earth connection only serves to act as "return" for imbalanced loads: The three phase "live" wires effectively act as each other's neutral, so that as long as they're equally loaded there is no need for return wires, thus halving the need for overhead cables.

This of course relies on there being not just one but THREE wires, all of which count as "live". Less than three and the scheme doesn't work.

However, as I understand it, [Ian], the system would work without a ground, on condition that the loads on the three phases were exactly matched.
-- TheLightsAreOnBut, May 10 2007


// do you need an input and output wire simultaneously or can you suffice with one wire that acts alternately as both?//

Again, you would not have a circuit, thus no current flow and as such no work can be done. There must be continuity in the circuit for anything to happen.

//However, as I understand it, [Ian], the system would work without a ground, on condition that the loads on the three phases were exactly matched.//

3 phase AC power DOES work without a ground. The Local ground or Chassis Ground is connected to metal components of an appliance, it is not connected in any way to the primary electrical circuit in a device(in general at least). This is why old houses and appliances can be hazardous as they can short out and you become the ground path if you touch them. The body of the toaster simply becomes an extension of the wire.
-- jhomrighaus, May 10 2007


Sorry, [xav], but it's all a bit on the wrong side.

As [jhomrighaus] has touched upon, the idea is fundamentally incorrect. In addition to Ohms Law, look up Kirchoff's circuit laws that can be basically linked to 'plumbing'.

If you get rid of the ground wire you break the circuit. So any voltage you apply to your input may provide a potential difference, but without a circuit, there is nowhere for the charge to go. At best you end up with a capacitor that is storing charge, at worst you get hee-haw happening.

If we apply a common ground to your circuit diagram you end up with a kinda half-rectified & sorta smoothed AC current. The prongs won't be DC when compared to ground, and they will not be DC when compared to each other due to the phase shift of the capacitor. Of course, that's all with a ground.
-- Jinbish, May 10 2007


I'd like to vote for this as an idea (completely halfbaked) and quite over my head but in the spirit of hb, just gets you lot all excited...

you are a funny bunch.

btw, love you lots.
-- po, May 10 2007


thanks po, love you too.
-- xaviergisz, May 10 2007


linky
-- xaviergisz, May 10 2007


//which equals 260 degrees - a full circle. //

Cool, New Math!

Youve been Halfbaking to hard there I.T.
-- jhomrighaus, May 11 2007


[po]: Back atcha babe!
-- Jinbish, May 11 2007


interesting link but there is something funny going on there, look close at the patent Application and you will find a notation about a "Conductive Body" #6 in the pictures. This is not mentioned or shown in the article but I think is why this works, this is novel but I think it still falls to the same set of rules as we have been discussing, the difference here is that he is transmitting the electricity in a free loop rather than a ground loop like normal transmission is handled. I need to think on it more but

I don't think this saves your device as presented, you still need some way to get current to flow and your device does not have it, but I think his does, its just unconventional and well hidden, but there none-the-less.
-- jhomrighaus, May 11 2007


I think the article is pretty clear - power is transmitted on a single wire.

The patent is giving detail about how this simple concept is applied to large scale power transmission. Because of the large scale implementation, additional features are added to enable the invention. But the basic concept remains - transmission of power on a single wire.

I am not convinced that single wire power transmission is particularly useful (at least on the large scale), but that should not detract from the fact that it works.
-- xaviergisz, May 11 2007


>transmission of power on a single wire.

This works to some extent on earth, as the return current (coupled by capacitance) is carried by "ground" i.e. the earth itself.

My uncle demonstrated the ability to power a 1/3hp (roughly 250W) motor on a farm with a single wire, with the return current carried by 6' stakes in the (fairly wet) ground at both ends. Apparently, this was commonplace in rural America when copper wire was expensive.

Unless you perform this demonstration in the vacuum of space, with no significant conductors nearby, there is always a "ground", and it can possibly serve as a return path.

The idea as presented, while not "groundless" as claimed, is bunk. -
-- csea, May 11 2007


look, if you think the "Avramenko one wire circuit" is a hoax just say so. I doubt that this company would waste several years and a tens of thousands of dollars (and commiting fraud in several countries while they're at it) pursuing patents on a hoax.

It's good to be sceptical, but not dogmatic.

I think it's quite uplifting to learn of a surprising new result in a well established field.
-- xaviergisz, May 11 2007


It is interesting but it does not work the way you think it does. It is not Groundless, its just a unique way to transmit power, you still need a current to do work and that is what is covered in the patent, that is the ground that you are planning to eliminate. Recall that your idea is not called "single wire power transmission", but rather "groundless electricity"
-- jhomrighaus, May 11 2007


//I think it's quite uplifting to learn of a surprising new result in a well established field.//

Alternative field, perhaps.
-- Ling, May 11 2007


Why don't you try it, xaviergisz? All you need is a couple of diodes, and you'd find it a good lesson in basic circuits.
-- ldischler, May 11 2007


just be careful with the 3000 volts, they will do a number on you if they get out of control.
-- jhomrighaus, May 11 2007


I'd love to do the experiment ldischler, but I don't have the equipment. Also, I think there's more to it than just sticking two diodes and any capacitor to any AC voltage (i.e. the components need to be choosen carefully). I think I'll leave it to the experts (in fact I just posted this as a suggestion on the Mythbuster website).
-- xaviergisz, May 12 2007


At high frequencies, you can treat capacitors like a short circuit... so the voltage between the two 'DC' terminals will be negligible (mainly due to any small phase difference).
-- Jinbish, May 12 2007


hence why you'd need to choose your capacitor and frequency carefully.
-- xaviergisz, May 12 2007


There's quite a story behind the frequency selection for the main power distribution system. As far as I remember, 30Hz used to be popular for trams. Frequency was not too high because of inductive voltage drop, and most areas settles at around 40-100Hz. When all the individual power stations started to link together, obviously they had to choose a common frequency, and most settled on a common 50 or 60 Hz, only for mathematical purposes. Unfortunately, for some reason, Japan decided to have both, so in one part of the country it is different from the other! From a Japanese colleague: one city it is different frequencies on different sides. I suspect that the Japanese were the first to make multi-input voltage and frequency power supplies.

It just happens to be that the mains frequency, that we have now, is pretty much the most dangerous for electric shock effect.

To reduce inductive volt drop, one technique is to group the conductors as close together as possible. If they are apart even by a couple of feet, it can make a large volt drop over transmission distances. Look at the 3 phase lines running down the road: sometimes they periodically swap centre and one outer line to balance the volt drops.

Assuming it would work, a single wire would need to consider 1. Low frequency 2. Conductor grouping for low inductance; both of which seem to contradict the requirements of single wire system. A ground return system would also need to consider reliability and resistance of the ground.
-- Ling, May 12 2007


Having a groundless circuit is like having a flattened waterfall. Without the difference in potential energy, the waterfall is merely a puddle. The puddle can be at sea level or at the top of the Andes Mountains, but it doesn't flow without a difference. The ground is the "low" end of the electric potential difference. You can't have energy transfer without there being a difference in the level of energy from one place to another. It just doesn't work. Current is a motion in static charges (or the energy which they carry to be more precise) and without a difference in energy levels there is no flow. It's water stuck in the pipe. I think you ought to just concede the web-scientists the point on this one.
-- WhereYouAt, Jul 22 2008


How I imagine this - If the puddle is shaken (AC potential change)- There will be localised volumes in the puddle that have a different potentials with respect to others . Linking those volumes will produce a current .

Problems - the localised current will be tiny with respect to the overal AC shake . - The materials needed to make the temporal change to potential so that there is a gradient between the two diodes (xaviergisz circuit) hasn't been factualised .

As a magician would say 'Anything is possible' {if you slightly change the goal and/or the path} .
-- wjt, Jul 23 2008


So you see the whole electric field as the ocean and differences in potential being like the waves that constructively and destructively interfere in it. Sometimes the waves are higher than the average sea level and some lower. I really don't see a way to link up those potential differences at all without contradicting the original thought of a current along a single wire.
-- WhereYouAt, Jul 24 2008


This would indeed work, it was already baked completely by Tesla. However, like most of his high voltage high frequency ideas, it suffered tremendously from losses and inefficiency.

He used a single wire to power a fluorescent type light bulb. The "return path" was capacitively coupled to the surounding walls, floors, etc..
-- ServoMan314, Jul 25 2008


I like this idea, and think it would work with limited efficiency. I've never taken a course on AC power electronics so I'm not going to try the math here.

My analogy for the proposed rectified system is a bathtub (wire) with water sloshing back and forth in it (AC current), someone's hand doing the sloshing in one end (power supply), two one-way valves at the top and bottom of the other end of the bathtub (diodes or something), a tube connecting the top and bottom valves, and a little waterwheel that spins as water flows through the tube.
-- sninctown, Jul 25 2008


Are old vacuum valves really analogus to taps. A diode will let the potential drop back to zero because the potential stays the correct side of the diode . Maybe that friction static generator is the early development of a true electronic valve .
-- wjt, Jul 27 2008


static electricity is an inconvenient way to do work. Information can be moved nicely but herding enough electrons back an forth to do work is going to be hopelessly inefficient. Resistance and inductance are still factors. Can anyone speak to the properties of non solid state capacitors as components for no-return signaling?
-- WcW, Jul 27 2008


See [link] especially on "stray capacitance" and "self capacitance."

A simple capacitor consists of two parallel plates separated by a distance. The capacitance is directly related to the area of the plates, and inversely related to the distance between the plates.

The earth can serve fairly well as one plate of a capacitor, and essentially any conductor can serve as the second plate. For smallish secondary plates (such as each part of [x'z]'s circut) the capacitance is extremely small beyond very small distances between plates.

So in addition to the fixed capacitor shown in the circut, there are "stray capacitances" between each of the circuit elements, the Earth, and any other conductor in the vicinity.

At high frequencies, capacitors serve as shorts, at low frequencies (dc) they can be considered "open circuits."

So the geometry, as well as the freqency of operation of the circuit must be considered relative to the Earth to determine how it will operate.

I'm not sure what is meant by "non solid state capacitor."
-- csea, Jul 27 2008


The junction of a plasma state transistor exhibits a relatively high capacitance for the number of molecules involved (if i remember correctly) and thus indicates that it might participate effectively in a system that uses static charge and discharge. Just thought i would see if that got any nibbles.
-- WcW, Jul 28 2008


Can one of the capacitor's plates be charged up and then sealed ? Then these static capacitors could be used to change a conductor's properties .
-- wjt, Jul 28 2008


//At microwave frequencies you only need a single wire (or tube). Just rectify it to get the power back out. You can prove this at home quite easily by ripping the core wire out of some of your tv cable - you'll still get a picture.//

Even at low frequencies it's possible to get a tiny bit of energy through a one-wire connection; to demonstrate this, connect one end of a neon bulb to a somewhat long straight piece of wire (e.g. five fieet)and connect the other to the 'hot' wire of an outlet. In many homes, the bulb will glow enough to be visible in a completely dark room. There are commercially-available circuit testers that operate on this principle.

Even though this approach works somewhat at low frequencies, it works much better at high frequencies. One major problem with it, though: most of the energy that you feed into the wire is going to go into the air, rather than into the intended load.
-- supercat, Jul 30 2008


"could be overcome with simple electronic design that recognises that ground is half-way between the top and bottom of the AC signal"

Read about why PID controllers have an "I" component as well as their "P" and "D" components. It can drift over time.
-- kevinthenerd, May 08 2017


[+] This is half bakery, so I'm not going to hold you for how impractical the capacitor would be. It's worth noting that this idea was precisely the sort of mental experiment that led to Maxwell's equations.
-- kevinthenerd, May 08 2017


No, [Ian] that's "maddening", not "mental" ...
-- 8th of 7, May 09 2017



random, halfbakery