Alternating current is actually a form of direct current (DC) that comes directly from electric generators to electrical motors. A DC current (alternating) alternator basically has a constant current going in both directions, i.e. when the engine starts, the current goes up and when it slows down, it drops down. AC appliances are connected in a similar way. They run on an electric current when they are turned on and turn off when they are turned off.
In simple terms alternating current flows in only one direction, in a single cycle. The maximum amount of electricity that can be generated by these generators is about 45 watts. Because of this power generation capacity, electricity is sent over long distances. One example of this type of power is the transfer over long distances over telephone lines. Another example is the movement of trains over long distances.
AC electric power is useful in many applications. It is used for air conditioning, refrigeration, telecommunication, lighting, heating and many other electrical applications. It has been a major help in the production of gasoline, diesel and other fossil fuels. The high level of efficiency as well as reliability of AC currents have made them highly favored by most industries.
There are three different kinds of alternating current: the magnetic field induced, the alternating current caused by an alternating magnetic field and the electrostatic field induced. Most of us are not familiar with the first one – induced currents. These can be more dangerous than beneficial. This is because they tend to create more of a magnetic charge at low temperatures than higher temperatures, which can cause harmful problems.
If you were to hook up a copper cable in a negative magnetic field, the flow of current would be very low. But, if the wire is placed in a positive magnetic field, there will be a huge current. Thus, both types have different purposes. Magnetic induction is best suited for low temperature operations while electrostatic induction is best suited for long term use. However, it can also produce a hybrid effect wherein the positive charge produced by the induction is opposite to the one produced by the conductors.
A recent discovery has brought about the beauty of the world of electricity by making use of direct current flows. When high frequency alternating currents are placed on a thin metallic layer, some of its conductors are bound to become energized. In turn, these conductors generate an opposite current in the opposite direction that is called a skin effect. By the skin effect, current flowing through a thin metal layer can become faster and stronger.
Such an effect can be harnessed in many ways. One of them is the application of an electric energy into mechanical pumps that can pump water uphill. In addition, it can also be applied to generate electric energy for electronic motors to run continuously. This way, we do not need to convert electrical energy into mechanical energy for pumps or for motors to run continuously. Instead, we just need to reverse the polarity of the incoming stream of electrical current and convert it into a flowing current. Such phenomenon can also be applied to generators to give electrical energy to a spinning fan or to a small turbine to generate power for an electrical appliance such as a refrigerator.
Such devices can be made to run on batteries that contain small amounts of energy that can power up the device for a long period. The amount of energy needed for such a device is not very large. Further, such devices can be made to run on free electrical energy that is acquired from the earth’s crust. Such an application may be applicable in space where there is no need to power up anything. Such an application may also prove successful in remote villages where most electrical appliances are electrical so there is no need to use electrical currents.