Alternator

Converting mechanical energy into electricity - that is the fundamental energy conversion which occurs in every power plant, regardless of the energy source used (water, wind, fossil fuels or nuclear fuel). This conversion is achieved using a generator. The operation is based on Faraday’s Law of induction (which states that an alternating or moving magnetic field induces an electrical current in a conducting circuit). The magnetic field can be derived from a permanent magnet, but for industrial production purposes, a powerful electromagnet is much more efficient.

Electricity production by means of a generator

In practice, a generator consists of a rotor rotating inside a stator. The rotor is an electromagnet which is "energized" by a direct current. The stator consists of a static cylinder with copper windings, in which a three-phase alternating current is generated as a result of the rotation of the rotor. The rotor rotates at a constant speed, in order to obtain an accurate mains frequency of 50 Hz.

Transformers are used to step up the voltage derived from the output of the generator to 380 kV so that the power losses experienced during the transfer to the consumer are minimized as much as possible. Due to the higher voltage, the amperage will drop correspondingly. The electricity is routed via a high-voltage substation to the interconnected network which links together the major power plants, both nationally and internationally. Finally the power is routed via transformer substations in order to supply the consumer with the required voltage.