As an Air Quality/Duct Cleaning specialist I am often consulted upon for my educational experience regarding indoor air quality issues. With the advancements being made in air filtration I am often asked for my opinion on various filtration options one of which are electrostatic furnace filters. As a duct cleaning technician myself, I am a strong advocate of electrostatic air filters.

I have written a brief summary of the benefits of owning such a filter

-Savings: Electrostatic air filters will help keep heating components and A/C coils from being coated with dust particles. Dirt is the #1 cause of heating & cooling system failures, and a cleaner system also operates more efficiently which saves you money on both energy consumption and equipment repairs. Additionally, Electrostatic filters are permanent which save you money on disposable filters.

-Allergy Relief: Asthma, allergy and respiratory symptoms can be significantly reduced when exposure to dust, pollen, mold spores and animal dander is controlled by the electrostatic properties of these filters.

-Housekeeping: Household dust will be collected on the electrostatic media of the filter when the furnace or A/C system is operating. Less frequent dusting will be a welcome benefit to housekeeping.

-Environmentally friendly: Electrostatic filters are a permanent lifetime filter, you will no longer have to toss out disposable filters every month into the landfill (The environment will love you for it)

-Easy to maintain: Instead of replacing your standard throw away filter, an electrostatic filter simply needs to be cleaned periodically to achieve best filtration results and optimum furnace efficiency.

Keeping your Air and Your HVAC system clean:

Having your duct system professionally cleaned is a vital part of dramatically improving the indoor air in your home. The addition of a high performance air filter will provide many benefits and intervals for duct cleaning. Electrostatic high performance efficiency furnace filters removes dust, pollen, mold spores and animal dander as the air circulates through your central system. Clean, filtered air benefits the entire family. Children and the elderly are most effected by indoor air pollution and will benefit greatly from the clean air that exits from this filter.

How does it work?

Electrostatic filters work on the principal of “static electricity” not “electricity”. The filter media has a Negative charge throughout the entire surface which is enhanced by air passing through, Tiny particles such as dust, pollen and mold have a Positive charge and are therefore attracted to the filter like a magnet . These particulates are the culprits of our indoor environmental air pollution. Electrostatic furnace filter is designed to trap these particles and remove them from the air that you breathe

The air that we breathe in our homes can be often saturated with undesirable elements. Some of these pollutants can include viruses, bacteria, dust mites, pet dander, etc. Inhaling these harmful substances and organisms can be detrimental to our health. Some of those ailments include respiratory problems such as pneumonia as well as the development or exacerbation of allergies.

To counter these pollutants in the home or at work there are various air purifying machines that are available to filter the air. One such machine is an electrostatic air purifier. There are many advantages to using an electrostatic air purifier in the home. Some of those advantages include their silent operation, no filters to clean and thorough cleansing of the air.

All of these advantages lead to a healthy environment that enhances the respiratory systems of the family unit residing in that home where the electrostatic air purifier is utilized.

Silent Operation

One of the important features of utilizing an electrostatic air purifier is the ability of the machine to run silently behind the scenes. This quietness is obtained due to the installation of a quiet, but effective fan. Other features of an electrostatic air purifier may include two sensors. One sensor may be adjusted for use in a bedroom. The other sensor adjusts automatically to the noise level in the room in which the electrostatic air purifier is running.

This technology allows for the electrostatic air purifier to operate during the entire length of the day including sleeping hours. This consistent operation allows for the continual filtration of the air within the home.

No Filters

Unlike other air purifying systems, the electrostatic air purifier does not rely on a standard filtration system. Rather than using filters, an electrostatic air purifier utilizes steel rods which act as collection points for the pollutants. These steel rods are very effective in capturing minute pollutants such as pet dander, pollen from flora and other common irritants. These rods can be removed and cleaned when maintenance is required.

Natural Cleansing of Air

Another benefit of utilizing an electrostatic air purifier is the advantage of having fresh smelling air which is an indicator of clean air within the home. The entire purification process leaves the air free from common contaminants in addition to serving as an air freshener.

This freshening of the air is accomplished by removing pollutants and odors and allowing the filtered air to be released back into the home. This revitalization of the air is accomplished naturally without the use of any chemicals or masking deodorizers.

Vacuum Technology & Coating product showcase includes power supplies used in a wide variety of vacuum-based production deposition and coating applications.

Deposition and coating systems require extremely dependable power supplies. Fortunately, a wide array exists to fit virtually any application. With increasingly demanding deposition and coating system requirements, and the ever present cost considerations for industrial and scientific applications, the expectations for power supplies increases.

Power supplies provide outputs of DC or AC in a wide range of power levels. Power supplies can have primary outputs ranging from very low to hundreds of kilowatts with frequencies from DC to 13.56 MHz or beyond. Depending upon the application, voltage or current regulation may be more important. Current ratings also can range from low to very high. These are but a few considerations when selecting a power supply.

Options Abound

How crucial is size and are matching networks and cooling systems needed? What kind of output programming and control are needed and what specific computer or network digital interface needs must be met? There are many choices to meet the user needs.

With DC supplies, there are steady and pulsed outputs. Typical DC power options include high-current, high-voltage and voltage-regulation. Pulsed DC supplies, for example, can improve surface uniformity in applications such as semiconductor wafer copper plating.

For AC supplies, many factors must be considered. High-frequency power sources must deliver reliable power for continuous, demanding use in vacuum applications including vacuum processing such as PVD, RF sputtering, plasma etching or deposition and reactive ion etching.

Very Reliable Power Required

Analytical instrumentation power supply voltage requirements can range from just a few volts to several hundred thousand volts, often with multiple critical voltages in a particular instrument. Standard and custom high voltage power supplies are used in instruments for spectroscopy and many other analytical imaging and process applications. Voltage ripple (or lack thereof), stability over time, repeatability and accuracy are factors to consideration if reliable scientific data are the goal. For analytical instrumentation used in production process control, reliability is very important.

The resonant frequency of this arrangement is determined by the values of the ballast inductance L and the tank capacitance C. The frequency is not affected by the winding resistance R or any resistive ballast added. (Typically the resonant frequency will lie between 10Hz and 500Hz.)
Resonance will occur regardless of whether the transformer is ballasted at the primary or the secondary, but it is easier to understand if we assume the ballast inductance is in series with the secondary side of the transformer. If this assumption is made then we can consider the HV transformer as presenting a stiff HV supply so the circuit can be simplified to get that shown on the left. The values of L and R are derived from an actual 10kv/100mA Neon sign transformer.

It demonstrates four things:-

1.It shows how important it is to use correctly set safety gaps to prevent excessive voltage rise if using a capacitor which is close to “matched” size.
2.It shows that the tank capacitance effectively cancels out the ballast inductance near the resonant frequency. In this example at 50Hz the current is 2A which is the result of current limiting by only the winding resistance. The inductive ballasting effect of the magnetic shunts is eliminated.
3.It shows that current will be drawn from the supply even though no power is being taken from the system yet. (There is no spark gap to discharge the capacitor.) The current flowing is reactive current and represents energy “sloshing” in and out of the tank capacitor as it is charged in opposing directions by the positive and negative cycles of the supply.
4.It shows the “shape” of the LC resonant response before the effect of a spark gap is introduced.
The addition of a correctly set spark gap will limit the amount of voltage rise permitted whilst still getting the benefit of the increased charging current.

Resonant charging can take place with both neon sign transformers and inductively ballasted power transformers. The only difference is that the ballast is built into the neon transformer. Power transformers, however, have much lower internal losses. This results in a higher Q value and causes more intense voltage and current rises around the resonant frequency.

Due to the intensity of the resonant rise effect, it is not always desirable to use a “matched” capacitor which causes resonance at exactly the line frequency. The graph below shows the effect of using “smaller than resonant” and “larger than resonant” capacitors on the same 10kv/100mA neon supply. (The supply still has no spark gap connected, only the tank capacitor.)

Spark gap misfires,

Because resonant voltage rise thrives on time, (time required for the voltage to build-up,) it is worth considering what would happen if our spark gap was to accidentally miss a firing. If a rotary gap misfires, there cannot be another firing until the next time that the electrodes are aligned. This means that when a firing is missed there is twice as long between discharges of the tank capacitor, and this allows the voltage to ring up to a higher voltage.

Computer based simulation packages such as PSpice are ideal for predicting what would actually happen in such circumstances without risking any expensive components.

While attempting to explain sparks and lightning to some friends, I realized that I didn’t have a good gut-level understanding of them myself. As usual, my lack of understanding was an attractive irritant, like a pimple that one can’t help picking at. And so over many months I kept noticing concepts that could be applied to explanations of sparks. Here’s what I’ve come up with.

To get a good understanding of sparks, you need to encounter their behavior in detail. One way to do this would be to magnify a small spark, but sparks happen so quickly that interesting behavior can’t be seen, so in addition to magnifying it, we’d have to slow it down somehow. Here’s a better idea: speed yourself up instead. Imagine that you’ve been exposed to Tholosian water from ‘Old Trek.’ This is the substance which causes you to live many times faster than normal. (TV-show science fiction trivia experts will recall the appearance of a similar drug on The Wild Wild West as well!) And then, instead of magnifying a tiny spark, let’s go outside during a storm and look at the behavior of an already-large spark. Except for its size, the strange behavior of lightning is very similar to the behavior of tiny sparks.

So, we’re standing outside in the time-frozen world of a raging thunderstorm viewed from our 1000X perceptual acceleration. The trees and bushes around us are thrashing frozenly in the stopped wind, and a few torn shingles flying from the nearby roof hang in the air nearby. Higher up we see a tangled, branching network of dimly glowing wiggly purple lines which look something like a tree root. And like a root, all the tips of the branches are lengthening. But this can’t be lightning, it’s dim and purple, not bright blue-white.

One branch-tip is about a hundred feet up from where we’re standing. We can see that the wiggly line isn’t moving, it’s only growing at its tip. It takes a tortuous, kinky path as it lengthens, and occasionally a new branch starts growing from the side of the main one at a spot where there is a particularly sharp bend. Then we notice something else: everything on the ground is starting to glow. Bits of dim purple fire are popping into existence on the tops of bushes, the edges of the roof of the nearby house, the tips of the rooftop TV antenna, on the ends of all the tree branches, and even on the flying pieces of roof shingles. As the exploring finger of dim purple lightning comes downward, the purple “fire” on all the objects becomes more and more intense. If you hold your hand in front of you, the tips of all your fingers spout dim purple fire as well.

Now the dim purple lightning from above is about thirty feet away, and the downward growth of its tip seems to be speeding up. Then something really disturbing happens. One of the purple flames coming from your fingers has suddenly started growing upward as a narrow wiggly violet line! You pull your hand down, but it’s too late, the streamer of purple stays attached and grows upward fast, it’s two feet long by now. You notice that this purple streamer from your hand isn’t the only one, there are now jagged purple lines growing upwards from many places which formerly had the little “St. Elmo’s Fire” flames. There’s a ten foot streamer coming from the tree, another from the bush, and a couple from the roof of the house and the TV antenna. They appear to be moving towards the incoming lightning strike. There are even several coming from the wind-blown shingles, but some of these are extending downwards towards the ground while others grow upwards. The one from you’re hand isn’t winning, it apparently had a late start, and the streamers coming from the tree and the shingles are really shooting upwards now ahead of all the others. And the downwards-growing streamer from the shingles has touched the ground and is spreading out into a small disk of purple rootlets on the surface of the ground.

Finally the upward-growing streamer from the shingles approaches the lightning streamer coming from above. The two growing branch-tips race together, and just before they meet they split into several separate branches which all connect. And NOW it suddenly looks like lightning, because the entire streamer from the shingles is glowing brighter and brighter. The little disk of purple filaments where it touches the ground is now several feet across and looks like blazing blue-white tree roots. The whole thing is far too bright to look at, and it’s getting brighter still. And something is happening to you. Your fingers hurt, the muscles in your arm are tensing by themselves, and you feel yourself blacking out. As you lose consciousness, you note that the short, dead-end streamer from your hand is still jutting upwards into the air, glowing bright blue, though nowhere near as brightly as the streamer from the shingles.

—–

What the heck was all that?! Lightning struck an object hanging in the air?! Well, sort of, since the shingles somehow launched their own lightning. And how could lightning be coming from objects on the ground, and from your hand? Why were you knocked unconscious even though you didn’t get struck directly by the main bolt? And isn’t lightning supposed to travel at the speed of light? 1000 times speedup is nothing compared to lightspeed, so why did we see the lightning as a bunch of slowly-growing filaments?

There are some mental tricks you can use to understand some of what went on above. Number one: realize that lightning is not made of electricity. “Lightning is electricity” is a false concept which stands in your way of understanding, and you need to get rid of it before you can figure out what’s going on. The long purple filaments which extended through the air are not electricity, they are actually made of air. They are nitrogen and oxygen which has been converted into plasma. Plasma is vaguely like fire, but it is not necessarily hot. When air is converted to plasma, the electrons of the gas atoms are knocked off the atoms and become able to flow along through the air. Plasma is a conductor, so it’s not too wrong to think of purple plasma filaments as being like wires made of conductive air.

Another mental trick: when you take a conductive object, a metal bar for example, and hold it in a strong electric field, flame-like “St. Elmo’s Fire” sprouts from the ends of the bar. The “fire” is nitrogen/oxygen plasma. And plasma itself IS a conductive object. So, if an electric field is strong enough, and if a tiny bit of air is somehow converted into plasma, it’s as if your conductive rod has grown little conductive pieces on its ends. And next, the “sharp” parts of the plasma globs will themselves sprout extra bits of plasma. And so your metal rod has started “lengthening itself” via fingers of air-plasma. The air can “catch fire” with an outbreak of plasma which grows and grows, with more air turning to plasma as the rods of plasma grow more plasma on their tips.

The plasma takes a particular form: long thin twisty rods. This occurs because “St. Elmo’s Fire” always starts on the sharpest part of an object, and the sharpest part of a rod is the end of the rod. And so a pre- existing rod of plasma will grow more plasma on its tips and lengthen itself. This self-forming plasma conductor is vaguely like a motorized metal antenna on a car which extends upwards. But the plasma-antenna can lengthen itself continuously as long as it’s tip is still in a strong electrostatic field.

If the twisted plasma rod should make a sharp bend as it grows, the bend can behave as a sharp point and more plasma fingers can take off from the bend. In this way a lengthening plasma streamer develops branches as it goes. Growing plasma doesn’t just form twisted rods, it often forms trees, it forms entire complicated systems of rootlets which advance and spread. Whether it forms trees or straight unbent paths depends on the shape of the e-field. in the space around it. A parallel e-field will allow tree-shapes to grow. A spreading, radial-shaped field will tend to force one plasma finger to grow faster than all the others, resulting in a needle-straight spark.

Since plasma is a conductor, what do you think would happen if a piece of air-plasma were to connect itself between two highly-charged objects having opposite charge? ZAP! The opposite charges would be shorted out. An enormous electric current would exist for a moment. This is what happens during a lightning strike, or during the tinyest spark. Long filaments of air-plasma within the clouds extend and explore downwards towards the ground and upwards into the charged raindrops. A system of fine plasma-rootlets develops which connects most of the raindrops to the main conductive plasma tree structure. When the conductive plasma touches the ground, it discharges both the charge on itself and the charge on the the huge number of electrically charged raindrops. The large momentary electric current makes the dim purple plasma explode with light and sound.

So, what about lightning and the speed of light? Why can we see lightning “strike” across the clouds, yet light itself moves so fast that we never see moving light beams? Why can we sometimes see sparks jump from object to object? This is because the growing motion of lightning and sparks is actually the growth of plasma filaments. It is not a movement of light. Lightning can “strike” slow or fast depending on how fast the plasma filament tips are extending themselves. In very large Tesla Coil systems, the giant sparks can lengthen VERY slowly, a human can sometimes outrun them.

In the speed-up story at the top of this page, how come there were plasma filaments appearing on the ground and growing upwards? And why did the wind-blown shingles send plasma filaments both up AND down? This is hard to explain without going into detail about electric fields and atoms. But here’s a similar question: suppose you squeeze a clod of dirt between your thumb and forefinger until it cracks. Would you expect the crack to start at your thumb, or at your finger? Or might it start from a small spot in the dirt and grow outwards in two directions at once? In truth, applying force to the dirtball can cause a crack to start ANYWHERE within the dirt.

Cracks tend to start at defects, and a similar thing is true with lightning and sparks. An invisible field of electric force, if applied to air, can cause plasma filaments to burst into existence anywhere in the part of the air where the field exists. When lightning is advancing towards the ground, there is a strong electric field all through the air around the plasma branch and in the space above the surface of the earth. This strong field can trigger new plasma filaments to grow anywhere. Of course its main effect is to make the main lightning filament lengthen and grow downwards. But those blowing shingles represented a “defect” in the air, they distort the invisible electrostatic field in the air and strengthened it near the shingles, just as a bubble in stressed glass can distort the mechanical forces and initiate a crack in the glass. The electric field present throughout the air caused two plasma dendrites to take off from the shingle and “strike” simultaneously upwards and downwards. The defect in the air caused the air to “crack” electrically, the crack being made of 3D plasma filaments.

The same thing happens when aircraft fly between oppositely charged parts of a thunderstorm: the plane acts as a triggering defect in the air, and plasma fingers launch themselves from two spots on the airplane. Flying a plane near a thunderstorm is like poking a highly-stressed windowpane with a nail: the cracks start where the nail touches. Yes, that’s right, research has shown that aircraft rarely are struck by lightning, instead the aircraft themselves do the striking, since the plasma starts on the wingtips and zips outwards, striking the clouds.

Still Under Construction
Of several electricity concepts, the idea of “voltage” or “electrical potential” is probably the hardest to understand.

It’s also really tough to explain. It’s a headache for both the student and the teacher.      To understand voltage, it helps if you first understand a little about its nearest relative, magnetism.

Most of us are familiar with magnetic fields. Small magnets are surrounded with an invisible “magnetic field” which pulls on iron, and which can attract or repel other magnets. The magnetic field causes oblong magnetic objects (such as iron rods, or iron powder) to twist and align to follow particular directions. Put a bar magnet under a piece of paper, sprinkle on some iron filings, and the filings line up and show the general shape of the invisible field. Obtain a small compass, and you’ll see the little compass pointer twist and align with the magnetic field of the earth. That’s magnetism.

There is another type of invisible field besides magnetism. It is called the “electric field” or “electrostatic field” or “e-field.” This second kind of field is a lot like magnetism: it’s invisible, it has lines of flux, and it can attract and repel objects. However, it is not magnetism, it is something separate. It is voltage.

Most people know about magnetic fields but not about e-fields or “voltage fields.” In part, this is because magnetism is explained in school, but for some reason voltage fields are hidden away under the name “static electricity,” and they’re never mentioned in beginner’s science textbooks. This is odd, since voltage and “static electricity” go together. Whenever a negative charge attracts a positive charge, invisible fields of voltage MUST EXIST between the charges. Voltage causes the attraction between opposite charges; the voltage fields reach across space. In reality, “static” electricity has nothing to do with motion (or with being static), instead it involves high voltage. Scuff across a rug, and you charge your body to several thousand volts. When you take a wool sock out of the clothes dryer and all the fibers stand outwards, the fibers are following the invisible lines of voltage in the air. Fibers are the “iron filings” that make the voltage patterns visible. And whenever charges flow through a wire, they only move because they’re being driven along by a voltage-field which runs through the length of the wire. “Voltage” causes dryer-cling, but it also causes electric currents in wires. Another way to say it: electric current is caused by “static electricity,” and “static electricity” is not necessarily static. The connection between voltage and “static” electricity is not explained in the books, and that’s one main reason why voltage seems so complicated and mysterious.

The Simple Math Behind “Voltage”
To be a bit more specific, Voltage is a way of using numbers to describe an electric field. Electric fields or “E-fields” are measured in volts over a distance; volts per centimeter for example. A stronger e-field has more volts per centimeter than a weaker field. Voltage and e-fields are basically the same thing: if e-fields are like the slope of a mountainside, then the volts are like the various heights of each different spot on the mountain. The slope of a mountainside can make a boulder start rolling. So can the differing heights of the different points on the mountain, it’s just another way to describe the same thing. “Voltage” and “e-fields” are two ways to describe the same basic concept.

When you have e-fields, you have voltage. E-fields can exist in the air, and so can voltage. If you have a high voltage across a short distance, you have strong e-fields. When an e-field is attracting or repelling an object, we instead could say that the object is being driven by the voltage in the space around the object.

How High is my Voltage?
Can an object have a certain voltage? No. Why not?

Well, please tell what my distance is. What is my distance? It’s a ridiculous question, because I didn’t say my distance FROM WHAT. Voltage is a bit like length, it is a measurement made BETWEEN two things. My distance is 300ft above sea level, but is also 1cm from the floor (since I’m not barefoot,) and it’s also 93 million miles from the sun. My voltage might be -250 Volts in relation to the earth, but it also might be billions of volts when compared to the moon. Volts are always measured along the flux lines of electric field, therefore voltage is always measured between two charged objects. If I start at the negative end of my flashlight battery, I can call that end “zero volts”, and so the other end must be positive 1.5 volts. However, if I start at the POSITIVE end instead, then the positive battery terminal is zero volts, and the other terminal is negative 1.5 volts. Or, if I start half way between the battery terminals, then one terminal is -.75 volts, and the other terminal is +.75 volts. OK, what is the REAL voltage of the positive battery terminal: zero, or +1.5, or +.75 volts? Nobody can say. The terminal can have several voltages at the same time. But this is no big deal, because neither can anyone tell you the battery’s distance! We can easily imagine the distance between two points, and we can also imagine the voltage between two points. But single objects don’t “have distance”, and single objects also don’t “have voltage.”

Un-twisting the Terminology
You’ve probably heard of “electromagnetic fields” and “electromagnetism.” In the word Electromagnetism, the term “electro” does not refer to electricity. Instead it refers …to voltage! Electromagnetism is the study of e-fields and magnetic fields: electro/magnetism. Charge flow (electric current) is intimately associated with magnetism, and separated opposite charges are intimately associated with voltage. A flow of electromagnetic energy along a cable is composed half of electric current, and half of voltage. It is “voltagecurrent,” it is electrostatic/magnetostatic, it’s electro-magnetism. Electromagnetism is a two-sided coin, so what is voltage? It’s one side of EM (the other side being magnetism.)

Besides not being found in elementary school science books, Voltage is also missing from our everyday language. If we have no common words to describe something, we tend to never talk about it. We even have trouble believing it exists. For example, we have the word “magnetism”, and most people have heard of magnetic fields. ELECTRIC fields exist too. Unfortunately “electri-cism” is not an English word. Everyone can discuss magnetism, but nobody ever talks about “electricism.” Without the word “electricism,” we have a hard time talking about electric fields and electric attraction/repulsion forces, and we never realize that they are important in electric circuits. Yet there is a word we could use instead of “Electricizm.” We don’t have to coin some weird new term.

If magnetism is “that which involves magnetic fields”, then what is “that which involves electric fields?” Voltage!

Pick up some nails with a magnet, and that’s an example of magnetism, then pick up some bits of paper with a fur-rubbed balloon, and that’s an example of voltage. What are the three kinds of invisible field? Gravity, magnetism… and voltage!

Perhaps we should change the word “Electromagnetism” into “Voltagemagnetism?” (grin!)

VOLTAGE SURROUNDS TWO ELECTRIC CHARGES     MAGNETISM SURROUNDS A MAGNET’S POLES
Electromagnetic Duality
Voltage and magnetism form a pair of twins; they are two halves of a duality. Physicists and engineers even use the word “dual” to describe them: voltage is the “dual” of magnetism, and magnetism is the “dual” of voltage. This duality raises its head in many places in the physical sciences. One small analogy: A spinning flywheel can store energy. So can a compressed spring. In electrical physics, a superconductor ring can store energy in the form of magnetism, and a capacitor can store energy in the form of voltage. A coil of wire and a capacitor are the “duals” of each other, since one involves magnetism, and the other is based on voltage.

Voltage Energy
Voltage is intimately connected with electrical energy. So is magnetism. We can even say that electrical energy is the fundamental object of our study, while voltage and magnetism are the two faces it displays to the outside world. Another analogy: in mechanical physics, both the Kinetic energy (KE) and the Potential energy (PE) are part of matter: relative motion of an object has Kinetic Energy, and stretched or compressed objects (e.g. springs or rubber bands) have Potential Energy. In a similar way, electrical kinetic energy appears whenever positive charges flow through negative charges. We call this “electric current,” and it causes magnetism. Electrical potential energy appears when positive charges are yanked away to a distance from their corresponding negative charges. We call this “net electrostatic charge,” and it causes voltage. Electrical KE is associated with current, and electrical PE is associated with voltage. If electrical energy is the same as Electromagnetism, then maybe we should be more sensible and name it “VoltageCurrent-ism.”

Potential Energy vs. “Potential”
Voltage is also called “electrical potential.”

So… is voltage a type of potential energy? Close, but not totally accurate. Think of it like this. If you roll a big boulder to the top of a hill, you have stored some potential energy. But after the boulder has rolled back down, THE HILL IS STILL THERE. The hill is like voltage: the height of the hill has “Gravitational Potential.” But the hill is not *made* of Potential Energy, since we need both the hill *and* the boulder before we can create potential energy. The situation with voltage is similar. Before we can store any ELECTRICAL potential energy, we need some charges, but we also need some voltage-field through which to push our charges. The charges are like the boulder, while the voltage is like the hill (volts are like height in feet. Well, sort of…) But we wouldn’t say that the Potential Energy is the boulder, or we wouldn’t say the hill is the PE. In the same way, we should not say that electric charges are Potential Energy, neither should we say that voltage is Potential Energy. However, there is a close connection between them. Voltage is “electric potential” in approximately the same way that the height of a hill is connected with “gravitational potential.” You can push an electron up a voltage-hill, and if you let it go it will race back down again.

Currents don’t have Voltage
Voltage is not a characteristic of electric current. It’s a common mistake to believe that a current “has a voltage” (and this mistake is probably associated with the ‘current electricity’ misconception, where people believe that ‘current’ is a kind of substance that flows). Voltage and current are two independent things. It is easy to create a current which lacks a voltage: just short out an electromagnet coil. It is also easy to create a voltage without a current: flashlight batteries maintain their voltage even when they are sitting on the shelf in the store. Water analogy: Think of water pressure without a flow. That’s like voltage alone. Now think of water that’s coasting along; a water flow without a pressure. That’s like electric current alone.
“Kinds” of Electricity?
Grade-school textbooks wrongly teach that electricity comes in two types: static electricity and current electricity. These textbooks would be much closer to the truth if they instead said this:

The two halves of “electricity” are “voltage electricity” and “current electricity.”

Still misleading, since the meaning of the word “electricity” is not clearly defined. It would be better if they said that electrical energy has two main characteristics: voltage and current. But the above statement is not nearly as bad as the stuff they teach about “static vs. current.”

For one thing, the stillness of the charges is not important. “Static” electricity is NOT electricity which is static. Instead, “static charge” really means “separated opposite charges”. We should not be surprised to learn that “static electricity” is able to flow from place to place without losing any of its characteristics. Maybe it’s not “static” anymore, but this doesn’t matter, since a separation of charge can move along. It’s the IMBALANCE between opposite charges that’s important, and their “static-ness” is not.

NOTE: Do you see how K-6 textbook authors could be playing a game of ‘telephone?’ In this game, words are progressively distorted by errors in communication. In K-6 textbooks the science concepts become more and more distorted over the years. Authors are taught from earlier textbooks, and often they get their information directly from modern textbooks. Then they write new ones. If authors make mistakes, what will happen? Start out by saying “electromagnetism has two complimentary halves, voltage and current”. Decades later we end up with books which are teaching kids something like this: “the two forms of electricity are static electricity and current electricity.” Wrong. Yet we can see where the crazy stuff originally came from.

Seeing the Invisible Voltage
Magnetic fields are invisible, and so is voltage. Both can be made visible. Iron filings let us see magnetic fields. To see voltage, suspend some metal or plastic fibers in oil, or sprinkle grass seeds on a pool of glycerine. If we then expose the oil to the strong voltage-field surrounding a charged object, the fibers or grass seeds will line up and show the shape of the field. Rub a balloon on your head, hold it near the suspended fibers, and you’ll “see” the lines of e-field flux.

Measuring Voltage
To measure current, we allow the magnetism around a coil of wire to deflect a compass needle. To measure voltage, we allow the “electricism” between a pair of delicately suspended metal plates to deflect one of those plates. The simplest voltmeter is called a “foil-leaf electroscope.” We find such things in books about “static electricity”, when they really should be in all electronics books. A more complicated version of the foil-leaf electroscope is called a “quadrant electrometer.” These two devices can measure voltage directly, without creating any electric current at all. Besides the moving capacitor plates, there are a few other ways to measure voltage too.

The Voltage of Light
Here’s a strange idea: Flowing Electromagnetic energy always has voltage. For example, if you touch the antenna of a powerful radio transmitter, you can receive an electric shock because of the high voltage at the antenna. Radio waves are electromagnetism, and the intense waves surrounding a radio transmitter’s antenna will have a high voltage-field. Radio waves can be measured in terms of voltage. Even the brightness of the light from the sun can be measured in terms of volts per meter. So can the energy which comes from the electric generators and flows along wires to a 120v table lamp. All of these involve electric fields (and voltage), and magnetic fields (and current.)

Expose All Students to High Voltage!
“High voltage.” Might you already know what that is? It’s not just the dangerous devices behind the electric company fence. High voltage is also balloons rubbed upon your hair, and “static electric generators” and their very long sparks. You might be interested to know that ALL voltage does the same things as “High Voltage.” The effects are just weaker. Understand “high voltage,” and you’ll understand voltage itself. High voltage devices are not just toys, they are educational: they let us experience voltage directly. If you want to understand magnetism, then play with electromagnet coils and bar magnets. If you want to understand voltage, then get yourself a VandeGraaff generator.

Voltage has wrongly been hidden within “static electricity” and declared to be an obsolete and useless science, important only for historical reasons. But in a certain sense, “static electricity” *IS* voltage. Static electricity is a high-voltage phenomena. If we stop teaching about “static electricity,” and regard it as ancient and useless “Ben-Franklinish” stuff, then we also stop teaching about voltage. Can you see why voltage has become such a mystery? We’ve nearly eliminated “static electricity” from high school science classes, and so we’ve also throw away our basic voltage concepts.

MISC.
Imagine a waterwheel being turned by a stream of water pouring from above. If the water is like the flowing electric charge, and the waterwheel is like an electric motor, then what is voltage? Voltage is like the height of the stream above the wheel, or like its slope from the top of the wheel to the pool below. Without a height difference, there can be no water current and no work done by the waterwheel. Without a voltage difference across an electric motor, there can be no electric current and no work done by the motor.

voltage is like an electrical pressure or push, it can cause electric charges to flow. Or, if flowing charge is suddenly blocked, this can cause a voltage to appear. But current can exist without voltage, and voltage can exist without current.

voltage exists in space, not just on surfaces. Rub an inflated balloon on your arm hairs, then wave the balloon around so it makes the hairs stand up. You are seeing and feeling voltage in the space between the balloon and your arm. Think about a 9v battery. The 9 volts aren’t on the surface of the battery terminal, they are in the space between the terminals, like the magnetic field between a north and a south pole. A 9v battery is like an “electret”, the electric version of a bar magnet.

An inductor (an electromagnet coil) is an electric current device. A capacitor is an electric voltage device. If energy is stored in a shorted coil, the energy is in the surrounding magnetic field, and there must be an electric current circulating in the coil. If energy is stored in a non-shorted capacitor, the energy is in the voltage field between the plates. If the short is suddenly removed from the inductor, there is a loud bang, and a huge voltage briefly appears. If a short is suddenly connected to a capacitor, there is a loud bang and a huge current briefly appears. Capacitor, coil. Electro, magnetism. “EM” energy.

voltage is the stuff that connects the protons and electrons of atoms to each other, and it connects atoms together to form objects. Pull on your finger, and you are feeling the microscopic voltage between the atoms. Without voltage, there would be no solids or liquids in the universe, just gas. When you break a solid object, you are defeating the attractive microscopic voltages which were binding it’s atoms together.

The bonds between atoms are often associated with a constant voltage. If one atom is positive and the other negative, then there is a voltage between them. If billions of atoms could be line up in parallel, the voltage of the atoms could be easily measured. What would happen if we could align billions of atoms in parallel? We’ve just re-invented the battery. A battery is a couple of metal plates immersed in liquid. At the surface of the liquid where it touches each plate, all the atoms line up in parallel, and a voltage appears between the liquid and the metal. That’s what causes the voltage of any battery: the micro-thin layer of atoms at the surface of the metal plates inside the battery. Everything else in the battery is just there to provide the electrical connections and the chemical fuel supply. Ideally, a flashlight battery could be three atoms thick (a thin film of liquid sandwiched between two thin metal films,) and it would still put out 1.5 volts.

Everyday electric motors operate by magnetic forces surrounding a coil, with electric current in the windings of the coil. Let’s call this sort of device by the name “current motor”. Electric motors in everyday life are invariably “current motors”, but “voltage motors” exist too. They operate because of voltage-forces between charged objects. The microscopic motors used in cutting-edge nanotechnology are voltage motors. The linear chemical-motors inside your muscles are voltage motors. The spinning cilia on the tail ends of bacteria are little voltage motors. The mechanical enzymes which assemble ATP molecules (the ‘energy molecules’ of the cell) are voltage motors. The tiny microscopic parts inside a living cell are like little robots. They all rely on voltage motors, none use magnetic motors.

Potential energy involves stretching, squeezing, pressure and forces. Voltage is associated with electric charge which has been “stretched” or “pressurized.” Spin a flywheel, that’s an analogy for electric current and magnetism. Stretch a rubber band, that’s an analogy for voltage and charge separation.

Is magnetism like a warping of space? Then so is voltage. Voltage and magnetism can be combined to become a traveling wave of warped space. We call these waves “light,” or “radio,” or “electrical energy.” When the Electric Utility Companies sell you some “electricity”, they really are selling you pulses of “space warp” which are guided to you by a pair of copper wires. They are selling you a combination of voltage and current. When voltage and current are there, electromagnetic energy is flowing down the wires.

What is electricity? This question is impossible to answer because the word “Electricity” has several contradictory meanings. These different meanings are incompatible, and the contradictions confuse everyone. If you don’t understand electricity, you’re not alone. Even teachers, engineers, and scientists have a hard time grasping the concept.

Obviously “electricity” cannot be several different things at the same time. Unfortunately we have defined the word Electricity in a crazy way. Because the word “electricity” lacks a distinct meaning, we can never pin down the nature of electricity. In the end we are forced to declare that there’s no such stuff as “electricity” at all! Here’s a quick example to illustrate the problem.

Do generators make electricity? To answer this question, consider the household light bulb. In a lamp cord the charges (electrons) sit in one place and wiggle back and forth. That’s AC or alternating current. At the same time, the waves of electromagnetic field move rapidly forward. The wave energy does not wiggle, instead it races along the wires as it flows from the distant generators and into the light bulb. OK, now ask yourself this: is an electric current a flow of “electricity?” If so, then we MUST say that the “electricity” sits inside the wires and vibrates back and forth. It does not flow forward. Next, ask yourself if electricity is a form of energy. If it’s energy, then “the electricity” DOESN’T wiggle back and forth within the wires, instead it’s made of EM fields and it races forward at high speed. But it cannot do both! Which one is “the electricity”, the wiggling electrons, or the high-speed EM field energy? The reference books give conflicting answers, so there *is* no answer.

If someone asks whether generators make electricity, it exposes a great flaw in the way we talk about “electricity”. If we can repair this flaw, perhaps our explanations will finally make sense.

Below are the most common meanings of the word Electricity. Which one do you think is right? Think about it carefully. If one of these meanings is correct, all the others must be wrong! After all, no “science term” must ever have several conflicting definitions. Unfortunately dictionaries and encyclopedias have all of these contradictions. (Click the links to find out more about each one.)

1. The scientist’s definition: “Electricity” means only one thing: it’s the electrons and protons, the electric charge. Examples: CURRENT OF ELECTRICITY. QUANTITY OF ELECTRICITY. COULOMBS OF ELECTRICITY.

2. The everyday definition: “Electricity” means only one thing: the electromagnetic field energy sent out by batteries and generators. Examples: PRICE OF ELECTRICITY. KILOWATT-HOURS OF ELECTRICITY.

3. The grade-school definition: “Electricity” means only one thing: it refers to the flowing motion of electric charge. Examples: “CURRENT” ELECTRICITY. AMPERES OF ELECTRICITY.

4. “Electricity” means only one thing: it refers to the amount of imbalance between quantities of electrons and protons. Example: “STATIC” ELECTRICITY. DISCHARGE OF ELECTRICITY.

5. “Electricity” is nothing other than the classes of phenomena involving electric charges. Examples: BIOELECTRICITY, PIEZOELECTRICITY, TRIBOELECTRICITY, THERMOELECTRICITY, ATMOSPHERIC ELECTRICITY …ETC.

6. Other less common definitions: “Electricity” refers to the flowing motion of electrical energy (electric power, Watts of electricity) “Electricity” really means the electric potential or e-field (Volts of electricity) “Electricity” only means the glowing nitrogen/oxygen plasma (sparks of electricity) “Electricity” is nothing but a field of science (Basic Electricity, Advanced Electricity)

If we wish to agree on a single correct definition of “electricity,” which definition should we choose? Well, maybe we don’t need to choose just one. Suppose we ignore all these contradictions and instead pretend that ALL of the above definitions are true. Below is the “clear” and “simple” description of electricity that results:

Electricity is a mysterious incomprehensible entity which is invisible AND visible BOTH AT THE SAME TIME. Also, it’s both matter and energy. It’s a type of low-frequency radio wave which is made of protons. It is a mysterious force which looks like blue-white fire, and yet cannot be seen. It moves forward at the speed of light… yet it vibrates in the AC cord without flowing forwards at all. It’s totally weightless, yet it has a small weight. When electricity flows through a light bulb’s filament, it gets changed entirely into light. Yet no electricity is ever used up by the light bulb, and every bit of it flows out of the filament and back down the other wire. College textbooks are full of electricity, yet they have no electric charge! Electricity is a class of phenomena which can be stored in batteries! If you want to measure a quantity of electricity, what units should you use? Why Volts of electricity, of course. And also Coulombs of electricity, Amperes, Watts, and Joules, all at the same time. Yet “electricity” is a class of phenomena; it’s a type of event. Since we can’t have an AMOUNT of an event, we can’t really measure the quantity of electricity at all… right?
Heh heh.

Does my description above sound stupid and impossible? You’re right. It is. The word “electricity” has contradictory meanings, and I’m trying to show what happens when we accept more than one meaning. Electricity is not both slow and fast at the same time. It is not both visible and invisible.

Instead, approximately ten separate things have the name “electricity.” There is no single stuff called “electricity.” ELECTRICITY DOES NOT EXIST. Franklin, Edison, Thompson, and millions of science teachers should’ve had a long talk with Mrs. McCave before they decided to give a variety of independent science concepts just one single name.

Mrs. McCave was invented by Dr. Seuss. She had twenty three sons. She named them all “Dave.”

Whenever we ask “WHAT IS ELECTRICITY,” that’s just like asking Mrs. McCave “WHO IS DAVE?” How can she describe her son? There can be no answer since the question itself is wrong. It’s wrong to ask “who is Dave?” because we are assuming that there is only one Dave, when actually there are many different people. They all just happen to be named Dave. Who is Dave? Mrs. McCave cannot answer us until she first corrects our misunderstanding.

For the same reason, we will never find a simple answer to the question “what is electricity?” because the question itself is wrong. First we must realize that “electricity” does not exist. There is no single thing named “electricity.” We must learn that, while several different things exist in wires, people wrongly all of them by a single name.

So never ask “WHAT IS ELECTRICITY”. Instead, discard the word “electricity” and instead use the correct names for all the separate phenomena. Here are a few of them:

* What is electric charge?
* What is electrical energy?
* What are electrons?
* What is electric current?
* What is an imbalance of charge?
* What is an electric field?
* What is voltage?
* What is electric power?
* What is a spark?
* What is electromagnetism?
* What is electrical science?
* What is electrodynamics?
* What is electrostatics?
* What are electrical phenomena?

The above questions all have sensible answers. But if you ask WHAT IS ELECTRICITY?, then all of the answers you’ll find will just confuse you, and you’ll never stop asking that question.

Electricity and water do not mix? Wrong! This device creates electrical energy by slowing down water droplets as they fall. It separates the positive and negative charges naturally present in all substances. It gives a high voltage DC output at a current of microamperes. The water exiting the bottom is uncharged, and you could easily feed it to another complete unit stacked in series.

The diagram below depicts a version built from funnels and aluminum jello molds or bundt pans (the ring-shaped kind with the large opening in the center.) However, you could build an enormous version if you were to replace the jello molds with large wooden barrels or 55gal drums with their bottoms cut out. ** bzZAP! **

This thing looks like some sort of particle accelerator. Actually, it is just the opposite. It decelerates charged particles and provides electrical energy, rather than using up electrical energy in order to accelerate particles.

WARNING: Note that this project is an advanced version of the classic Kelvin Thunderstorm device outlined in amasci.com/emotor/kelvin.html. If you’re a beginner, then to get the hang of these devices…

…I STRONGLY SUGGEST THAT YOU BUILD THE OTHER, SIMPLER ONE FIRST.

Also, the other article gives hints on making the generator blink a little neon bulb, or make clicks in an AM radio, deflect tissue strips, etc.

Optional rain collector?
|____                _____|
\______________/
\    /
\  /        Metal              | SIDE VIEW     |
||         Funnel             |               |
||                            | BILL B’s      |
| WATERDROP     |
__________     Jello Mold         | ELECTROSTATIC |
/ \      / \   (positive inducer)  | GENERATOR     |
|___|____|___|                      | (Connecting   |
| wires not     |
__________                        | shown)        |
/ \……/ \    Jello Mold with
|___|____|___|   metal screen (negative
charge collector)
______
\    /
\  /       Metal
||        Funnel
||
__________
/ \      / \    Jello Mold
|___|____|___|  (negative inducer)

__________
/ \……/ \    Jello Mold with
|___|____|___|   metal screen
(positive collector)

\               /  Bowl to catch
\             /   water
\___________/

The diagrams to the left and right show an ‘indoors’ version. I used plastic Tupperware bowls as the water sources. I drilled a circle of tiny holes in the bottom of each, using a #64 drill bit. This creates a “shower head” effect and greatly increases the output current. Ideally you should connect the water in the two bowls to ground, but since they each supply opposite charge, you can just connect them to each other. Drop the metal end of an alligator cliplead into each.

Note: actual polarity of charges is spontaneously chosen at start-up. The above “positive” and “negative” labels are for convenience, and will end up backwards half the time.

PARTS:

* 4 - Metal bundt pans or jello molds ( $0.50 each at garage sales!)
* 2 - Metal funnels, or plastic bowls w/holes poked in the bottom
* 2 - Cones made from metal window screen
* 3 - lengths of thin plastic tubing or fishing line, about 3ft long, used to hang the parts of the device from the ceiling.
* misc - Tape or glue for the screen and the fish line, alligator clipleads to connect the pans together, old scissors to cut the metal screen.

THE SCREENS
You should shape the metal screens in the collectors to make them either bowl-shaped or funnel-shaped. This will force the water to fall from the center of the screen rather than running down the edge of the charge collector pan. If water drips from the edge of the charge collector rather than from the screen, it will remove charge from the collector. And if the water from the screen forms a long solid stream whose tip extends vertically past the bottom edge of the pan, it will discharge the collector pan and the device will stop working. Only droplets, not streams, should leave the collector ring’s central hole.

If you use a simple, pointed, cone-shaped screen, and if all the water falls from the tip in a solid stream, the collector ring discharges itself and the device stops working. I’ve found that a good shape for the screen is a shallow cone with the tip punched inside-out like this (cross section):

_
\         / \         /
\     /     \     /
\_/         \_/

The water falls as droplets from the bottom edge. Make the screen cones fairly shallow, so no parts of them extend vertically outside the central hole of the ring pan. The pan acts as an electrostatic shield, and when water touches the inner, shielded part of the pan, *all* of its excess charge will travel to the metal. If the screen is within the sheilded volume, it will extract all the excess charge from each water drop. The screen must remain down inside the donut-hole of the pan.

_____                           _____
/     \                         /     \
|       |           _           |       |   Bundt pan with
|       |\         / \         /|       |   cone of screen
|       |  \     /     \     /  |       |   within its hole.
|         |   \_/         \_/   |         |
|         |                     |         |
|- - - - -|                     |- - - - -|

I used black electrical tape on the edges of the screen to hold it in place in the pans. You could tack it with silicone caulk for a more permanent design. Don’t forget, the metal screens must make electrical connection to the metal pans. Keep each screen and pan touching together in at least one spot; don’t accidentally break their connection with insulating silicone caulk.

CONSTRUCTION:
The entire assembly of bundt pans and funnels can be suspended by fishlines from a hook on the ceiling, or instead you could build some sort of plastic structure to hold the parts.

The upper rain collector can be plastic or metal, or possibly use the downspout from a convenient roof, or a hose, etc. The water supply should be small enough that the funnels don’t fill to overflowing.

Whether you use a funnel or a bowl with small holes, you must somehow limit the amount of water flow so that it either comes from the bowl or funnel as single drops, or as a short stream that breaks into drops inside the inducer ring. If the stream is too long and the drops break loose below the inducer ring, the inducer ring won’t charge the drops and the device won’t work

You can increase the electric output current by fitting some sort of metal “shower head” assemblies onto the ends of the metal funnels. These are sold in garden stores as adapters for watering-can spouts.

If metal funnels are too expensive, you can also try using Tupperware bowls with numerous small holes drilled in their centers. I put six holes in mine, spaced in a circle about 2cm apart to prevent the water streams from sticking together. To connect the plastic bowls to ground, stick a piece of aluminum foil in the water in the bowl and clip your alligator clipleads to the foil. “Ground” can be a water faucet, the screw on an electric outlet, a big sheet of aluminum foil laid on the floor, or even your body if the humidity is high.

The rings and funnels should be one or two inches apart. It’s OK to let the end of each funnel extend within the hole of each inducer ring below, as long as the droplets break free of the stream before the stream exits bottom edge of the inducer ring.

To suspend the rings and bowls, I glued three small Plexiglas “ears” on all the rings and funnels. Then I ran three lengths of #20 plastic insulation “spagetti” tubing up the sides, tying it to each “ear,” then tying the whole thing to a hook in the ceiling. I could have used fishing line instead. Don’t use wire to support the rings, not even if it’s insulated wire. The support must be a very good insulator. To speed things up you might try simply tying knots in the right places in the fishline, then glue the knots to the pans with gobs of silicone caulk. (Use tape to hold the lines in place while the caulk sets.) Hang the whole thing from a ceiling hook.

ELECTRICAL CONNECTIONS:

______
\    /  Grounded
_____\  /   Funnel
|      ||    w/shower head
V      ||
/\
__________
__ / \      / \ _________________o
|  |___|____|___|
|                                    Output leads
|                       __________o
|    __________        |
|   / \……/ \ ______|
|  |___|____|___|      |
|                      |
|                      |
|      ______          |
|      \    / Grounded |
|   ____\  /  Funnel   |  Connect the bundt pans
|  |     ||            |  together using bare wires
|  V     ||            |  and tape, or using alligator
|        /\            |  clipleads found at Radio
|                      |  Shack stores
|    __________        |
|   / \      / \ ______|
|  |___|____|___|
|
|    __________
|__ / \……/ \
|___|____|___|

This device seems to work even in extremely high humidity. Apparently the electrical leakage along the surfaces of the thin plastic fishline is small enough that the device can still work even with that leakage present. Thinner fishing line might work even better, since the thinner the support lines, the less their surface area. The less their surface area, the less the electrical leakage during high humidity.

Any liquid can be used as long as it is slightly conductive. In theory oil will not work because it’s an insulator. Too bad liquid mercury is poisonous, mercury would work fine. Tapwater works OK, since impurities make it conductive enough. I doubt that salt water would work better, but it would be something to experiment with. Ultra-pure de-ionized water might not work because it’s almost an insulator. For a science fair project you could even try fruit juice. When people ask you why, just say “because acids create mobile ions, leading to higher conductivity, and also because I wanted to make a big, sticky, disgusting mess!”

DEBUGGING

Did you build the “classic” Kelvin generator first? If not, then I can’t help you. This “in-line” version is an advanced project. It’s much more flakey and difficult to make operate. Beginners should go back and try the “four coffee cans” version first.

For further info, debugging, references, and “how it works,” see my other article,

NOTE: avoid using wood to support metal parts! See “debugging” notes at the end. See FURTHER INFO at end too.

It is possible to build a very simple high-voltage generator which has no moving parts and is powered by the energy of falling water. By dribbling water through some old soup cans, several thousand volts magically appear. The magic lies in the fact that water (as well as everything else!) is made of vast quantities of positive and negative electric charge in perfect balance. It’s not too hard to cause an imbalance. Water normally has zero net electrical charge because it contains equal and opposite charges. “Kelvin’s Thunderstorm” is a gravity-powered charge un-canceller.

+  + +
+|||||| +
||||||
||||||   Water
||||||   Dripper
||||||
Negative charge   ||||||
is ‘induced’ at    \  /
tip of dripper    - || -
- _ -

_           + + + + + + +
-o-        + ————– +
-        + |     A        | +
+ |  Positively  | +
_        + |  Electrified | +
-o-       + |  Object      | +
-        + |              | +
+ |              | +
Negatively               + ————– +
electrified     _           + + + + + + +
water          -o-
droplets        -

-             -
- |               | -
|               |    Collector Can
- |–__—-____—| -  becomes Negative
|               |
- |               | -
|               |
- |_______________| -
-    -     -

Fig 1. WATER DROPLETS BEING ELECTRIFIED BY “INDUCTION”

THE BASIC THEORY

Even though water has no overall electric charge, it is full of movable electric charges (called ions). Half of the water’s charges are positive and half are negative. It is not hard to separate these charges; simply hold an electrified object near the water. The electrified object will attract the “unlike” charges to the water’s surface. It will also repel the “alike” charges away deeper into the water.

In the above diagram, the positive object attracts the water’s negative ions and repels the positive ions. This draws an excess of negative ions into the tip of the water dripper, while repelling an equal amount of positive ions off to the other end of the dripper. When the water drop detaches from the tip of the dripper, an overall negative electric charge is still trapped in the droplet. The falling water droplet carries away negative charge, leaving the dripper slightly positive. If we catch the falling droplets in a container, the container will become negatively charged.

In the above diagram, negative water droplets will be continuously created forever as long as the water flows. However, this process does not exhaust the imbalanced charge on the positive object. Sounds like perpetual motion, eh? Actually no. The electrical energy is being created by the work that gravity does in pulling the negative droplet away from the grounded dripper, and away against the attraction of the positive object. The electrical attraction force from the positively-charged object keeps the tip of the dripper charged negatively, but the positively charged object does not supply energy. YOU supply the energy, since you LIFT the water to a height to fill the dripper. It’s like the generator in a hydroelectric dam, but without the turbine or the spinning coils or magnets. The water itself becomes the moving parts of an electric generator.

(Note: the charge polarities can easily be reversed. If the above “object” is made negative, the droplets would come out positive.)

BUILDING A GENERATOR
If we can make a positively-charged object somehow, then we can make negative water droplets. But where can we get a positive object? If there was some way to CHANGE the negative charge on the water into a positive charge, then we could use the water to charge up it’s own “positive object”. We would then have a a self-sustaining generator. There’s a simple way to do this: build TWO water-drop devices like the one in figure one! See the trick? The device in figure one uses a positive object to create negative water. It uses positive to create negative. If we build a second device, we could use the negative to create positive. We could hook the two devices in a loop. The first one would create an imbalance of negative charge, which could be fed to the second one which would create an imbalance of positive charge, which would be fed back to the first one again. It might sound crazy, but it really works.

We will build two of the drippers in Fig. 1, set them side by side, then collect the electrified water droplets from one side and use them to electrify the “charged object” on the other side, and vice versa. We’ll cross-connect the lower and upper parts with wires. One side will have a positive “object” and will make negative droplets, while the other side will have a negative “object” and will make positive droplets. We’ll also connect the drippers together so they remain neutral. Then we will have a self-sustaining electrical reaction.

_______________________
_   __________________  \  Water Supply
\ \                   \ \
\ \                   \ \
\ \                   \ \ Drippers (metal,plastic,glass)
||                    ||
||                    ||
||                    ||  Connect the water supply to a
||                    ||  metal faucet using a wire, or
||                    ||  to the screw on an electric
||  Wire not shown,   ||  outlet or wall switch.
see next diagram
(below)
|    |                 |    | Bottomless metal coffee cans,
|    |                 |    | or wire rings, or bundt pans,
|    |                 |    | or metal disks with large holes
|    |                 |    | (supported by insulating rods.)
|    |                 |    | Called “Inducers.”  These
act as the “charged object.”

|    |                 |    |  Metal cans on insulators
|    |                 |    |  (styrofoam? insulating rods?)
|    |                 |    |  The “Collectors.”
|    |                 |    |
|____|                 |____|
|  |                   |  |   The “inducers” and “collectors”
|  |                   |  |   should be separated from each
|__|                   |__|   other by several inches

Fig. 2 TWO DROPLET-CHARGERS PLACED NEAR EACH OTHER (see below for wires)

See Fig. 3 below. Wires connect the two sides together. The negative droplets touch the lower Collector-can of the first side. The collector can is electrically connected to the upper negative Inducer of the second side. The negative Inducer will cause the second side to make some positive droplets. The positive droplets of the second side will touch the second lower collector can, and this will charge the upper Inducer can of the first side positively. (This makes the first side produce negative droplets.) The grounded drippers must be connected to each other and to ground. See Fig. 3 below to see how the wires connect things together.

Highly recommended: ELECTROSTATICS by A. D. Moore (lots of projects), also others

SELF-STARTING

But where does the first charge come from? In fact, if you build such a device, it will usually create voltage all by itself, spontaneously, without being pre-charged. During dry conditions everything near the generator ends up with a tiny electric charge just from being handled. If one of the upper cans is slightly negative, it will cause the water to have imbalanced positive, which will start up the other side of the generator, which will make the charge on the negative side become larger, etc., over and over.

It’s like balancing a penny on edge: it’s hard to start out with a perfect balance, and usually it falls one way or the other. Same with this generator. If there’s a tiny electrical imbalance at the start, the generator will amplify it over and over, and the voltage will “fall over” to either one polarity or the other. A high voltage will magically appear from nowhere. (But nobody knows which side will start out positive and which will be negative.)

CONSTRUCTION

The metal parts of the generator must be supported with insulating materials. A large vertical sheet of acrylic plastic works well. So does styrofoam plastic. Don’t use wood for the supports, it’s too conductive. Fasten the collectors and inducers to the plastic sheet with screws or silicone caulk, or make holes in the sheet and tie them to the sheet with string or wire. Some people have used plastic rods or plastic strips to support things. Other people use plastic water pipes. The plastic must be clean and dry. The inducers and collector cans must be spaced away from each other by several inches horizontally and vertically. The lower collectors must be kept away from the table surface.

Bare wires are used to cross-connect the four cans. These two diagonal wires must be far from any other conductive object, and the wires must not touch together. Use bare wire, this will let you create sparks between the wires, or to later flash a NE-2 neon bulb.

Connect the ends of the diagonal wires directly to the metal of the cans. If you use plastic-covered wire, strip off the plastic coating from an inch of each end of the wire. You can use tape to hold the wire against the metal, as long as the wire touches the bare metal directly (not, for example against the painted part of a coffee can.) Alligator clipleads (bought from Radio Shack stores) work well for this. Or poke a hole in the metal near the edge of the can, stick the wire through the hole, and bend it and tape it so it doesn’t fall out.

___________________________
_   _______________________ \
\ \                       \ \
\ \                       \ \
\ \                       \ \
||                        ||
||                        ||
||                        ||
||                        ||

|  o |                     | o  |
|    |                     |    |
|  o |+    +         -   - | o  |
+ |    |—-\            /—|    |  -
|  o |  +   \ +    - /  -  | o  |    (no connection
+ \    /                  between the
o            C/           o        crossed wires!)
- |    | -       / \       + |    | +
- |  o | -   - /   + \     + | o  | +
|    |_____/         \_____|    |
- |—-|   -             +   |—-| +
|____|                     |____|
|  |                       |  |
|  |                       |  |
|__|                       |__|

Fig. 3 LORD KELVIN’S THUNDERSTORM, W/WIRES SHOWN

The upper rings (or cans) must be positioned near the place where the water droplets break from the rest of the water. If the droplets break away right at the tip of the nozzle, then put the nozzles within the upper cans. If a solid stream of water comes from the nozzle and breaks up further down, then move the nozzels up, so that the water-break spot is inside the upper inducer cans.

For the Drippers, you can use glass or plastic “pipettes”. You want to have a very small hole, so that the dripper makes lots of tiny droplets. If you cannot get a pipette, try poking holes in a plastic container. See below.

Adjust the water flow so it drips VERY fast. The faster, the better. Even better, use lots of drippers instead of just one.

OPERATION

Once you have the water dripping, you can expect high voltage to immediately appear. After the device runs for a minute, touch one of the coffee cans gently with a finger and listen for the tiny snap of a “static” spark. If you don’t hear a spark, the machine is running weakly or not al all. See the “debugging”" section near the end of this article.

If you can’t hear any spark, you can try detecting sparks electronically with an AM radio. Place a radio a foot away from your generator, tune it between AM stations (or tune it to a very weak station), and turn the volume up. Run your Kelvin machine. Touch one of the cans with your finger and listen to the radio. You should hear a “snap” noise as your finger touches the metal. Touch one upper can, then the other, then the first one again. You should hear a “snap” each time. Even when sparks are too small to hear or see, a radio will sometimes still detect them.

FLASHING A NEON BULB

Once your machine is able to produce sparks, you can also make it flash a small neon lightbulb. Normal flashlight bulbs won’t work, you need a small neon “pilot light” bulb instead. Obtain an “NE-2″ or other similar neon light, the kind which looks like a short glass tube with two parallel wires inside and two bare wires sticking out of the glass. Hold the bulb by one wire, look at the tube, then use the other wire to touch one of the cans of your Kelvin device. You should see a dim orange flash inside the bulb. (It might help to turn off the lights and work in a dimly lit room.) Hold one bulb wire, then use the other wire to touch the positive can, then the negative can, then the positive, and you should see a tiny orange flash each time.

CONTINUOUSLY FLASHING BULB

Don’t connect the NE-2 bulb directly across the two generator wires. It will short out the generator and prevent high voltage buildup. You can make the generator automatically flash the neon bulb by making a “spark gap”. First twist one wire from the neon bulb around one of the generator’s diagonal wires, then bend the wires so other short wire from the neon bulb is very close to the other generator wire ( but not touching). Small sparks will occasionally jump across the small gap and flash the neon. The smaller the gap, the faster (and dimmer) the flashing. Try a 1/16 inch gap (1 mm) at first. If it works, increase the distance to get slow, bright flashes. Bend the sharp tip of the wire over to form a little ring, this sometimes lets the voltage rise higher before a spark jumps, which lets the bulb flash more brightly.

FLAPPING KLEENEX

To “see” the high voltage surrounding the cans, tape some strips of tissue paper to the cans. Put tape only at the top of each strip of tissue so the strip hangs down against the side of the can. When the can charges up, the strips should lift slightly outwards. The higher the voltage, the farther the strips move. When a spark jumps, the strips jerk because the repulsion force suddenly becomes less.

SLOW-FALLING WATER

The energy that builds up between the cans comes from the falling of the water. As the stored energy grows, the water has to do more and more work every time it adds a bit more imbalanced charge to the cans. The electrified droplets feel a repulsion force as they fall towards the alike-charged lower cans. As the voltage increases, the droplets will fall more and more slowly. The sound of the splashing water will change. The droplets may even start bending their paths, even occasionally falling upwards!

EMPTYING THE LOWER CANS

If the device is run for very long, the lower cans fill up. How to get the water out of the cans without discharging them? Here’s my addition to the classic Kelvin Waterdropper: use the “faraday ice pail” effect, where a conductive hollow object always has no charge imbalance on its inside. To do this, connect an exit tube inside each lower can as below, so the water DRIPS out (if it falls in a solid stream, the cans will discharge and the generator will stop working.)

||                 ||
||                 ||
||                 ||
||                 ||
||/\/\/\/\/\/\/\/\/||
||                 ||   For best results, no
||                 ||   sharp edges or burrs
||     WATER       ||   anywhere.  Or, cover
||                 ||   sharp edges with thick
||     __   __     ||   bead of RTV silicone
||    |  | |  |    ||   caulk
||    |  | |  |    ||
||    |   U   |    ||
||    |   O   |    ||
======       ======
O
Uncharged droplets
O  exit from bottom

Fig. 4 REMOVING THE WATER FROM THE LOWER CANS

Or, even simpler, install a cone-shaped piece of metal window screen inside a bottomless can, so the water droplets touch the screen and continue through. Make sure the screen is centered vertically within the can, so that the point of the cone doesn’t extend past the lower lip of the can. Don’t let the water drip from the edge of the can, otherwise it will carry charge away with each drop.

With a little catcher-tray and a fountain pump, you can make the system recirculate. Or, you can stack all four parts of one Kelvin device in a single row, for an in-line waterdropper generator. See my article on “Inline Kelvin Thunderstorm Device” found on my site at

http://amasci.com/emotor/ikelv.html.

Note that the Inline version is more tricky to make work. Build the above device first before attempting the one below.

\ \
\ \
\ \
||
Grounded     ||
Dripper     ||
||
o
o
|   |
Neg     |   |
can     | o |
|   |

Pos      |   |
can      |…|
w/screen  |   |     Connecting wires not shown, see
|   |     ikelv.html article for more info

\    /    Connect pos to pos, neg to neg
Grounded     \  /
Funnel        ||
o
|   |     Note that this is a more advanced
Pos     |   |     project, and is more difficult to
can     | o |     debug than the side-by-side version.
|   |

Neg      |   |
can      |…|
w/screen  |   |
|   |
o

Fig. 5 IN-LINE VERSION (wires not shown)

The water supply need not be a “dripper”, it can be a high velocity spray, as long as the water jet divides into droplets, not a contiguous stream. And multiple jets can be used, sort of like a shower head. The faster the flow and the larger the number of separate streams, the higher the total output current. (Higher current gives faster recharge rate after a spark, and it lets the generator self-start more reliably when humidity is high.)

GIGANTIC VERSION

I’ve always wanted to build a gigantic version like the one below, with hollow metal toroids. (Use halves of VandeGraff spheres, the halves with the holes). Or maybe use metal 55-gal drums. But the drums have sharp edges, and we can’t attain millions of volts if the edges are sharp. A foil-covered truck innertube should support about a million volts before air-corona leakage stops the voltage from rising any higher.

Four tori
\\                           \\     (shown cross-
\\                           \\    sectional)
\\                           \\
||                           ||
||                           ||   water
||                           ||   spray
||                           ||
___           ___             ___           ___
/   \         /   \           /   \         /   \
|     |       |     |         |     |       |     |
\___/         \___/           \___/         \___/

___           ___             ___           ___
/   \         /   \           /   \         /   \
|     |\     /|     |         |     |\     /|     |
\___/   \_/   \___/           \___/   \_/   \___/

conical screens in lower torii touch droplets and
release, discharging them.  Entire screens must be
deep within the “hole” of each donut so the torus can
shield the departing water droplets from the electrical
fields on the outside.

Fig. 6 GIANT KELVIN DEVICE BUILT FROM SPUN-METAL DONUTS (or tire inner tubes covered with aluminum foil!)

High-velocity shower heads and cross-connecting conductors made from large-diameter pipes will complete the scene above: a “VandeGraaff Generator” version of Kelvin’s Thunderstorm apparatus!

NEWS: I suspended a bundt-pan by fishlines, then sprayed water through the center, so that the water did not touch the metal. I used a garden hose with a “water breaker” (a sort of shower head attachment.) I charged up the bundt pan with a 10KV power supply, and then measured the electric current between a collector pot and ground. It was 2.5 microamps! This doesn’t sound like much, but it’s as much as some VandeGraaff generators can put out.

I found that if I disconnected the power supply from the bundt pan, the current did not vanish. The charge on the bundt pan stayed the same as I watched for about 30sec. And this was in high humidity conditions! Fishing line makes a VERY GOOD insulator. The system kept working until I touched the bundt pan with my finger, then the electric current coming from the collector can went to zero.

RUNNING A MOTOR

The above generators can be used to run a motor, if the motor is my Pop Bottle Electrostatic Motor at:

http://amasci.com/emotor/emotor.html

I find that these small Kelvin Waterdrop Generators are a little too feeble to keep the motor going continuously. Instead they make it slowly pulse. They build up a charge imbalance, then the motor starts turning and rotates a few times. This exhausts the charge imbalance, the motor stops, then it builds up again and repeats. This happens a couple of times per minute. A bigger waterdrop generator is needed if you want to run the bottle-motor continuously.

MULTIPLE DRIPPERS

I put multiple drippers on my waterdrop generator and this improved things considerably. The best generator uses lots and lots of tiny drops, with the drops being made as fast as possible. If we use a cluster of dripper nozzles, the inner ones probably act as electrical shields for the outer ones. This is bad, since this will prevent the inner ones “seeing” the charged inducer cans, and they won’t make any electrified water. Therefor a CIRCLE of nozzles is probably best.

I drilled a circle of eight tiny holes in a plastic bowl (using #64 drill bit), and this gave good results. A crude version of multiple-dripper: use a soup can, and punch a bunch of holes in the bottom by using a tiny nail. I’ve also seen a shower-head thing called a “water breaker” in the garden supply section of hardware stores. If a circle of tape was stuck to the center of one of these, it would plug up the middle holes and form a ring of about 100 tiny water jets.

SPEEDING UP THE RECHARGE

Whenever a spark discharges the generator, it also discharges the inducer rings. As a result, the generator takes quite a while to “ramp up” to full voltage again. This is exponential growth, and it’s quite slow at first. There are several possible ways to solve this problem (I haven’t tried them, you be first!) One solution is to insert very large resistors in series with the wires to the inducer rings (large = thousands of megohms). Then always discharge only the collectors, not the inducers. The resistors will keep the inducers from instantly discharging. If the inducers remain charged, then the generator will quickly recharge with a fast linear voltage curve rather than a slow exponential curve. High-value resistors are expensive, so perhaps try making your own resistors. Use strips of paper with fine lines of india ink (india ink is conductive carbon.)

Another possibility: rather than using resistors, instead insert high voltage diodes. For example, use several 7,000-volt microwave oven diodes in series, available from Allied Electronics. Orient the polarity of diodes to allow the Inducers to charge but not to discharge. Diodes in one conductor should point upwards, and in the other conductor should point downwards. This way the collectors will charge up the inducer rings, but when you discharge the collectors, the diodes will turn off and become nonconductors. The excess charge on the inducer rings will remain high. Also, if you use diodes, the generator polarity would always be predictable, since the generator would not function if the polarity became reversed.

A third method: build a big generator, but don’t connect the collectors to the inducers. Then build a second tiny water-drop generator, and use it to charge up the inducers of the big generator. Then always discharge only the collectors of the big generator, and leave the other metal parts alone.

If you want to use your generator to power a pop-bottle electrostatic motor, the above idea is the way to go. Build a separate generator to power the inducers of the larger generator, that way the motor cannot “short out” the inducer voltage and make everything stop.

Now that I’m thinking about it, here’s another type of generator to build: a half-kelvin device with only two cans. How can it ever work? Simple: use the screen of a TV set to charge the inducer! I bet that this would even work when the humidity is really high. A TV set normally cannot produce constant electrostatic energy output unless you keep turning it off and on. But it should be able to supply enough energy to power the inducer ring on half of a Kelvin’s Thunderstorm device.

WEIRDNESS: antigravity?

If your generator really works well, you will see water droplets slow down and their paths curve upwards! No, this is not antigravity, this is just electrostatic repulsion. Alike charges repel.

WEIRDNESS: really really gigantic generators

In a private conversation someone told me that there were patents on a wind generator based upon the Kelvin Generator. Build two big parallel vertical metal screens the size of outdoor movie theater screens (or larger). The upwind screen has coarse mesh, the downwind screen has fine mesh to gather water droplets. Suspend them on insulators which are good for millions of volts. Charge the upwind screen with a power supply. Spray a fine mist of water into the screens upwind, and let the wind push the spray through the screens. The upwind screen will attract imbalanced charges into the sprayer tips, and the water droplets will have an imbalanced charge of opposite polarity. The wind takes the place of gravity in the classic Lord Kelvin device. Wind pushes charged water to the second, fine-mesh screen. Water droplets touch this screen and deliver their charge. The wind is slowed by repulsion of the water mist, the upwind screen uses no current, and the downwind screen puts out amperes at millions of volts of electrical potential (amps times megavolts equals megawatts). Simply step down the megavolts of DC, then convert it to AC. Ta-da, a wind generator with no moving parts! An artificial thunderstorm, harnessed as a commercial generator, powered by the wind.

DEBUGGING:

If your project will not work, it may be because the humidity is high and your device is having trouble “deciding” which side should be positive and which side negative. See my hints about humidity, found at http://amasci.com/emotor/statelec.html. With Kevin generators it takes voltage to make voltage. If your device starts totally at zero, it may take a minute or two to build up to maximum. Therefors give it a “goose” by holding an electrified object briefly near one of the cans while the water is running (for example: a balloon, a 2liter pop bottle, or some styrofoam, each rubbed on hair to electrify them.) This gives the generator a “kick start.”

The two drippers must be neutral, so they need to be connected together electrically. To make certain they’re neutral, connect a grounded wire to their water supply. These drippers should drip FAST. Many droplets per second. If your drippers are very slow, then your machine will charge up very slowly or not at all. To produce a fast drip rate, usually you need a tiny hole at the end of your water tubes. Plastic or glass pipettes are the usual way to accomplish this. Also, your machine will work better if you have many drippers.

If you really cannot get your generator to work, here’s a way to “cheat.” Put a piece of aluminum foil on a TV screen, connect this foil to one of the inducer cans on your generator, and then turn on the TV. This will make your generator run, at least temporarily. Don’t let any water get near the TV set!!!

AVOID WOOD

Kelvin Generators usually can tolerate fairly high humidity. Watch out though. Materials with large internal surface area, such as wood, cloth, masonite, etc., usually absorb moisture from the air and become slightly conductive. Therefor, assume that these materials are the same as metal, and avoid using them as supports or framework when you build this device. Wood provides a leakage path and shorts out the high voltage. One experimenter even found that problems were caused by supporting their cans with insulating blocks glued to a wooden panel. The short lengths of plastic must not have been sufficiently insulating, and there must have been a leakage path across the plastic and through the wood. Switching to all-plastic supports solved their problem.

If acrylic sheets such as plexiglas(tm) or perspex(tm) are not available, large styrofoam blocks work well as supports. Avoid using solvent-based glues with styrofoam, it makes it dissolve. The plastic MUST BE CLEAN. Use new plastic if you can. If you wash the plastic, don’t use much soap, since soap can form a conductive coating. Rinse it and scrub it with lots of clean water to remove all the soap. If you wash the plastic, then afterwards dry it thoroughly with an electric hair-dryer gun (but be careful, don’t melt the plastic with too much heat!)

Nylon fishing line makes a good insulating support, especially during high humidity conditions. Long, very thin supports such as fishing line have small surfaces and therefor give less surface-current leakage than short, fat supports or flat panels. Don’t use twine or string as supports, of course, since these materials become too conductive when the humidity is high.

If humidity is very high, even plastic can become slightly conductive. This can be temporarily fixed by using an electric hair-dryer gun to dry the plastic surfaces. Bathe the plastic in hot air for several minutes, taking care not to heat it so much that it softens! Try testing your generator again, and it may begin to work.

The water droplets must not touch the inducers. The droplets should pass through the inducers. The droplets should break free from the water while they are still inside the inducers. If continuous streams of water (not droplets) shoot out of the drippers, then move the drippers upwards to make certain that the droplets break away from the continuous streams while the droplets are inside the inducer cans.

The water droplets MUST touch the collectors. To start, simply let the collectors fill up with water. Once you have succeeded in getting sparks from your machine, then later you can try the trick with the cones of window screen (see far below.)

To detect the tiniest charge imbalance, build the RIDICOLOUSLY SENSITIVE CHARGE DETECTOR shown elsewhere on my web pages. (http://amasci.com/emotor/chargdet.html) This device will detect a few hundred volts of electrostatic potential at a great distance from the cans. It is extremely sensitive. The tiniest sparks won’t begin until the cans reach about 1,000v potential, yet the sensor responds to about ten times less. A sparking Kelvin generator can make the Charge Detector flash even if it is many feet away.

Don’t neglect the balloon trick. If your device doesn’t self-start, then momentarily hold a charged balloon near one of the cans while the water is running. (Verify that the balloon is really electrified, see if it raises your arm-hair when rubbed. Sometimes humidity is so high that the balloon will not aquire an imbalanced charge by rubbing on hair.)

A simple way to detect static charging: place a portable AM radio near the device, tune it to a blank station, then touch one of the cans with a finger. If your device is just barely working, there will be an imperceptible spark. But this will make a loud click on the radio! If you wear an AM Walkman headphone radio, it will extend your senses so that you can hear the electromagnetic pulses given off by the tiniest spark. Become a “Borg” from Star Trek, with the ability to hear electromagnetic impulses via a biointerface to electronic circuitry (Walkman headphones). Try spending the day wearing AM radio headphones tuned to an empty spot on the dial, and you will encounter all sorts of interesting electromagnetic “sounds” in the environment. You’ll hear the “crack” noises of distant lightning even when the thunderstorms are too far away to hear the thunder. Electric fences in countryside farms make a periodic clicking. The overhead wires from electric city buses make all sorts of musical tones.

The Electrophorus

Cut out a disk of cardboard about 8″ to 12″ in diameter. Cover one side with aluminum foil, and fold the foil up over the other side so it partially covers it. Attach some sort of insulating handle to the center of the remaining cardboard area (tape a plastic or styrofoam cup to the cardboard, or glue a small block of styrofoam) When holding the disk by its handle, the far side of the disk should be entirely covered with foil, and your fingers on the handle should be some distance away from the foil.

_
| | Handle
| |
=================== Foil-covered cardboard

Next, get an easily-charged object such as a balloon, or a thick plastic sheet, plastic cutting board, styrofoam packing block, etc. Also get something that can be used to electrically charge this object through rubbing, such as a piece of (artificial) fur, a wool sweater, a wig, your hairy head or arms, etc.

You need a low-humidity day to operate the Electrophorus successfully. To test humidity, rub your plastic object with the fur or sweater and see if it becomes charged and makes the fur stand on end when it’s held close to the charged area on the plastic. If you can’t get the plastic object to raise the fur, wait for a less moist day. Or go into an airconditioned building and try again. (Or sometimes a warm sweater fresh from the clothes-dryer will work. But don’t use anti-static fabric softener!)

To operate the electrophorus, place your plastic object on a table and rub its surface with fur or wool to charge it well. Or if your hair is clean and without grease, try rubbing the object on your head to charge it up.) Place the cardboard/foil disk upon the charged surface, foil side down. With the disk still on the plastic, touch the foil to allow it to steal charge from your body. You’ll feel a tiny spark.

\  \ finger
\_ \
__\ \ \            _
\\\\_\\\         | | Handle
\\       | |          Foil-covered cardboard
>TOUCH!<    ===================
|_____________|
Styrofoam block

Now, while holding the disk only by the insulating handle, lift it from the charged surface. The disk is now charged, and it can be used to blink a small NE-2 neon bulb, or to create small sparks, to deflect an electroscope leaf, pick up lint, charge a Leyden Jar capacitor, etc.

Even though it has been used to charged the foil, the plastic object still remains fully charged. It need not be rubbed for a while and can be used to charge the foil plate again and again, since the charging of the foil DID NOT remove any charge from the plastic. This seems impossible? The charged plastic in this generator acts more like a magnet than like a source of energy, and it does not lose its strength when it attracts charge into the foil. But from where does the electrical energy come? It comes from the work your arm did in pulling the foildisk away from the plastic surface.

The electrophorus WILL run the Soda Bottle motor very slowly. (If humidity is high it will not work.) Connect the foil of one of the motor’s bottles to ground. (water faucets connect to ground, or connect to the screw on a wall switch cover plate.) Charge the electrophorus disk and touch it to the foil on the OTHER, non-grounded motor bottle. Do this over and over fairly fast, and the motor will slowly turn.