Charging a battery free by static electricity

[fredericponcet]

Bonjour.

I find it hard to believe that the radio waves are enough to make a spark on a vouture candle, it seemed to me that the voltage developed between a wire antenna and the earth are of the order of a few volts.

Static, I would like to believe, since somewhere, static electricity is the source of lightning.

I'd be curious to know what voltage it takes to pop an arc on a car spark plug

I agree. Besides, electromagnetic waves induce an alternating current which could not charge the capacitor.
This assembly has everything of a machine to accumulate static charges, but without moving parts thanks to the spark plug which plays the role of spark gap.

I believe that the voltage at the terminals of a car coil is counted in KV (I have in mind 15 KV but I am not very sure anymore) but that does not mean that such a voltage is necessary to initiate. In fact, it also depends on the humidity of the air (the drier it is, the easier it starts).

[moinsdewatt]

be careful it would seem that this system
neither picks up lightning nor static electricity !!!!
but many radio waves

the candle will play the role of capacitor (not very effective)
the transformer auto coil

the goal is to transform radio waves (also called ELECTRO-magnetic) of the order of 110mili-Volts into 12V


here it is
A+

Yan

Gné?

The TV waves received by the antennas give microVolts. That's why there are antenna amplifiers.

[dedeleco]

amusing:
This thread seems to be 7 years old:
https://www.econologie.com/forums/post1215.html#1215
and has not evolved a bit considering the clear explanation given by gegyx at the time:
https://www.econologie.com/forums/post9655.html#9655


The length of the spark indicates the voltage approximately with 30000V per cm and therefore 1 mm of candle corresponds to approximately 3000V !!
Sparks can be seen over a few tenths of a millimeter, or a few hundred volts.

The radio waves are not strong enough, except a few meters from a powerful transmitter (KW), as done first by Hertz who discovered them in 1886 when he saw small sparks on his receiver:
http://fr.wikipedia.org/wiki/Heinrich_Rudolf_Hertz
http://en.wikipedia.org/wiki/Heinrich_Hertz
http://de.wikipedia.org/wiki/Hertzscher_Dipol

This radio or microwave voltage decreases as the square of the distance.

There is another phenomenon however at the origin of atmospheric electricity, the friction of air on objects which electrifies them !!
Between the drops of water from a thunderstorm, it gives lightning.

On a rolling car, a real capacitor C of a few hundred PicoFarad, this gives the spark that shakes when you grab the car handle !!

The collecting wire or plate (better) in this system thus collects the charges of friction and those of the atmosphere, especially since dry and insulating air passes over it quickly, like before a thunderstorm by giving tension, exactly like on a car that shakes you when you touch it, electrified after driving !!
This voltage can reach tens of thousands of volts, like when you rub glass on a cat's skin !!

Normally, in the atmosphere, we have 100v per m with a very weak current, but that goes up to thousands of volts per meter, at the approach of lightning.

We cannot measure this voltage with an ordinary commercial voltmeter with an internal resistance typical of a few megaOhms, because the very very small capacitor is discharged well before having given something detected by the voltmeter, which observed vinzman with zero !!! !!

So it can work, in hot weather with dry air, which charges your car with electricity, at the rate of a few thousand volts per km of air which passes over your wire or collecting plate well insulated from the ground (but metal touching the air) and the discharge of C = a few hundred PicoFarads into the coil, (your car mounted on insulation or any similar capacitor, Leyden jar, or metal plates separated by a good insulation of at least 0,5mm, without leaks), gives, with each blow, an energy of 1 / 2CV ^ 2 in Joules !!
C = 10 ^ -10F V = 3 to 10KV (1mm gives 3000V) or 0,45 to 5 milliJoule per spark.
At best we have one per minute and to charge a 12v and 1Ah battery or 43200Joules it will take 8,6 million discharges or about 6000 days or 16 years of good weather in airc close to a storm !!!

[fredericponcet]

AT(...)
The length of the spark indicates the voltage approximately with 30000V per cm and therefore 1 mm of candle corresponds to approximately 3000V !!

I think there is an error.

http://fr.wikipedia.org/wiki/Champ_disruptif#Le_champ_disruptif_de_l.27air

[dedeleco]

Public chat
http://fr.wikipedia.org/wiki/Champ_disr ... de_l.27air

This interpretation is better known as the “30 V per cm rule

We can interpret this formula in a very simple way, saying that in dry air, it takes a potential difference of 36 volts to make a spark between 000 points separated by 2 centimeter, or 3600 Volts to spark between 2 points 1 mm apart.

gives for 1mm = 1, 3000cm 2500V approximately between 3600 and XNUMXV since the shape of the electrodes change this non-uniform electric field a lot by peak effect which can trigger the spark at much less average voltage over the interval. !!!

[fredericponcet]

My mistake.

[moinsdewatt]

Good post above by Dedeleco. I don't have much to add.

With a small solar panel of nothing at all and a little sun you will charge your battery much more surely and efficiently.

[dedeleco]

Even while pedaling on your bike to exercise !!

[fredericponcet]

A few remarks about the above demonstration:

1) the friction of air on an insulating material (such as the paint of an automobile body) produces an accumulation of static charges. On a conductive material connected to earth, this produces a current;

2) the spark-ignition frequency in the proposed assembly depends on the capacitance of the capacitor. Q = C. U, therefore U is all the higher, for a given charge, that C is small. With a low capacity, the ignition voltage is reached faster and discharges are more frequent (but the transmitted electric charge is independent of C. It depends, a priori, only on the dimensions of the sensor and on leaks due to the humidity). The ideal is undoubtedly to vary C to optimize the charging current according to the atmospheric conditions of the moment.

3) a photovoltaic panel certainly produces a much higher current. But experimentation on photovoltaics is no longer within the reach of amateurs and the subject of this thread related to electricity of atmospheric origin.
Atmospheric electricity represents a large quantity of energy, of which thunderstorms (a physicist roughly estimated the energy dissipated by thunderstorms over France at 20 MW) are undoubtedly only the "overflow". Considering its principle of formation, one could call it diffuse wind energy. Unfortunately, it is difficult to collect, like everything that is diffuse. But that's exactly what is exciting.

[moinsdewatt]

...
Atmospheric electricity represents a large quantity of energy, of which thunderstorms (a physicist roughly estimated the energy dissipated by thunderstorms over France at 20 MW) are undoubtedly only the "overflow". Considering its principle of formation, one could call it diffuse wind energy. Unfortunately, it is difficult to collect, like everything that is diffuse. But that's exactly what is exciting.

20 MW is not an energy. But a power.