Let us say you have installed a solar power system at your rooftop and right now you are enjoying the air of a fan, powered by the solar panels.
Have you ever imagined the type of energy conversions going on within the system?
Principle of solar power system
Let me re-iterate the energy law, it states that the energy can neither be created nor destroyed but can be converted from one form to another.
In this particular case, the sunlight is converted into electrical energy by the solar panels and this electrical energy is further converted into mechanical (rotational energy) energy by the motor fitted inside the fans, hence giving you air.
Within the above conversion pattern, one more conversion is going on within electrical energy itself. Its direct current to alternating current and the inverter does this job.
Alternating current vs Direct current
The main reason for this conversion is that our electrical appliances are tuned to alternating current and cannot run on direct current.
Although both are the types of current, the basic difference between the two is that one has constant value and flows in one direction called direct current while another change/reverses its direction periodically, alternating between the minimum to the maximum, called alternating current.
You know our engineers are very intelligent people, they designed a.c. tuned appliances because they have certain advantages over D.C.:
How alternating current is produced?
The teachers told you that current completes the whole circuit to let the lamp glow. She was talking about the direct current then.
Then how does the alternating current make bulb glow because it does not flow in one direction but makes a to-and-fro motion?
The to-and-fro motion of the alternating current vibrates the filament of the bulb resulting in heat production which makes the bulb glow.
But the question is still unanswered that how alternating current is produced?
Let us draw another circuit:
Now if I combine the two wave-forms, it will look like as follows:
The sine wave inverter
If I can switch this arrangement alternately then I am producing alternating current. And if I’m fast enough to switch this arrangement 50-60 times in 1 second then I’m producing an alternating current of 50 Hz- 60 Hz frequency similar to what we get in our households.
The arrangement in the inverter is not different what we have discussed above but it has a more sophisticated design of producing alternating current.
The oscillator converts direct current to alternating current. Now the alternating current produced is of low intensity which cannot drive the main coil. Therefore, this current is needed to be amplified and the amplifier does this job.
The solar panel converts solar energy into direct current and it is the inverter which converts direct current or voltage into alternating current or voltage to run our electrical appliances.
So, the solar power system as a whole produce alternating current as the output.