This idea was posted here on Friday, January 29, 2010.

Many years ago, probably about 1968 or 1969, while I was attending classes at Texas A&M University, I took a class in electric motor theory.  It's been a long time and I don't remember most of what I learned in the class.  However, one idea stuck with me.  To the best of my memory, it was called a tuned circuit.  If that's the wrong name for it then, hopefully, one of my readers will so inform me and I'll be able to print a correction in a later issue of this newsletter.

The instructor taught us that, if a capacitor and an inductor are placed in parallel across an incoming AC line, and if the inductance and the capacitance are correct, then the two devices will form a tuned circuit.  The distinguishing feature of a tuned circuit is that there will be an alternating current flowing in the loop that's represented by the inductor and the capacitor but without any current at all flowing in the incoming AC line.

I immediately had an idea.  Sadly, back then I was too insecure and too bashful to raise my hand in class.  Indeed, I doubt if during my entire seven years in college I ever raised my hand in class more than about six times.  I'm not exaggerating.  I was that bashful.

The next weekend that I went home, I proposed my idea to Poppa.  He was an electronics technician by training and by trade.  He knew more about electric theory than most of the professors at A&M did.  I suggested that, if a tuned circuit was arranged so that the inductor was actually the primary winding of a transformer, then you should be able to run a load on the secondary winding of the transformer without drawing any current from the AC line.  That would be free electricity.

He said that, indeed, it would work.  The catch, he told me, was that the load had to be constant.  If the load varied even a little then that variation would be transferred to the primary winding of the transformer as a change in the inductance of the inductor.  That would cause the circuit to no longer be a tuned circuit.  I pressed the issue, asking why it wouldn't work with a constant load.  He said that, with the correct inductance and capacitance and with a constant load, it would work.  I asked him why people didn't use the idea.  He didn't have a complete answer but he said that he thought that maybe, sometimes, people did use tuned circuits in the way that I'd suggested.

Today, my questions remain.  A transformer and a capacitor don't cost much.  A tuned circuit could be designed into the input line of, say, an air conditioner.  The air conditioner would be a constant load.  I don't see any reason why a person would have to pay for electricity to run the air conditioner.  It ought to run constantly, for free.  The addition of a tuned circuit to the equipment would add slightly to the original cost of the equipment, but not much.  The increase in cost ought to be recovered during the lifetime of the equipment.

If any of you know of a reason why it wouldn't work, then I'd be interested in knowing the reason.  If any of you have the skills to build and test such a device, then I'd be interested in knowing the results.