The previous article, "Basics of the solar electricity" explained the process of generation of the solar electricity when sun light falls upon semi-conductor material. Now going ahead, this article deals with the different types of solar photo-voltaic systems.
These different types of solar PV systems are coined on the basis of the individual's electricity needs, the back required when sun is not available and of course the feasibility of your solar roof based on your needs. Well, in order to use, consume, preserve and store the energy from the solar panels we need other components like solar charge controller, inverter and the batteries for the back up, to make the required configuration. Yes, the diode plays an important role for the smooth functioning of your solar PV system which I am not discussing in this article.
All or some of the above mentioned components are required depending upon the type of the solar PV systems.
There are 4 basic types of solar systems which are as follows:
(1) The Direct system
This is the simplest of all the solar electric systems. This does not have the battery backup. The PV array is connected to the DC load through charge controller and connected to the ac load through inverter. This system produces electricity when the sun shines and stops when sun light is not available. This type of system is generally used in fields to run motors which provide water to the fields.
(2) Off Grid system
The off grid system has a battery back attached to it. The size of the PV array should be large enough to produce electricity to run electric appliances and the same time should be able to charge the batteries, whose power can be used to produce electricity when there is no sun light. These types of system are best suited for locations where there is no grid supply like mountainous region of India.
(3) Grid Tied system with battery backup
This is very much similar to the off grid system but it is also connected to the grid supply. The benefit of this system is that if grid power is down then the electricity can be used from PV array or the battery bank. It is able to produce electricity from PV array without drawing energy from grid supply. This is best suited for the locations where the cost of the electricity from the grid supply is expensive like in metropolitan cities. This system helps in saving units thus saving money.
(4) Grid tied system without battery backup
This system is almost similar to the direct system but it adds grid supply in its configuration.
So,one can design solar PV systems as per one's requirement based on his/her electricity needs, budget, location and the feasibility of the solar roof in that location. The efficiency of your solar roof depends on the quality of solar panels (along with inverter and the solar charge controller) you are using while designing the required configuration. The use of good quality solar components can significantly improve the payback period and the financial feasibility of your solar PV system. Adding of batteries for the backup increases the setup cost of the your solar roof, therefore it is required that one must first calculate the feasibility of the solar roof before implementing it.