I'm interested in what kind of energy has electric current ?. For everything I taught in school should have kinetic energy because electrons are on a certain potential within the electric field when the switch is closed then the electrons move and the electric current is "generated" which then should have the kinetic energy. And so I was thinking all the time until I came across this article http://amasci.com/miscon/energ1.html which actually tells me that everything I know about the electric current is wrong On the other hand, I wonder if so many books from college ,schools, are spoken in the wrong way It's just a little weird that a huge number of scientists and engineers are actually talking nonsense all the time and so I hope that you can help me clarify my dilemma.
thanks in advance.
Best Answer
In electromagnetism energy is stored in form of electrical and magnetical fields.
Energy flow is described by the Poynting vector and Poynting's Theorem, which is similar to the Continuity Equation of other forms of energy, basically saying that change of energy per time inside a volume equals rate of energy going through the surface and rate of energy being lost/generated inside the surface of the volume (e.g. by work done).
The Wikipedia article contains this demonstrative picture illustrating Poynting's vector (blue arrows). They allways point into direction of EM energy flow.
As you can see electrical energy comes out of the battery (where is was created from chemical energy) goes to the right and goes into the resistor (where it is converted to heat). It does NOT go in a circle (like the charge carrier's net movement).
Answering your question from the comment:
Q: Why are currents and voltages still neccessary?
A: Although this picture shows only electrical field (red arrows) and magnetic field (green arrows) currents and voltages play a role: electrical field is caused by nodes of different potential (voltage) and magnetic field is caused by electrical current through a line.