Types of Solar Modules
Classified by its manufacturing technology and the semiconductor, the solar modules are divided into three major types. They are Crystalline Silicon PV Module, Amorphous Silicon PV Module, and Hybrid Silicon PV Module.
Let’s learn in details about each type of silicon module.
Crystalline Silicon PV Module
- In order to produce this type of PV module, the two types of crystalline silicon (c – Si) are used.
- The two types of crystalline silicon are single crystalline silicon or monocrystalline silicon and multi-crystalline silicon or polycrystalline silicon.
- The multi-crystalline silicon PV module has a lower conversion efficiency than the single crystalline silicon PV module.
- But both types of crystalline PV modules have higher conversion efficiencies that average about 10-12%.
Amorphous Silicon PV Module
- The Amorphous silicon PV module is also called as thin-film silicon PV module.
- This thin-film PV module can absorb the light more effectively than the crystalline silicon PV module.
- It makes the best choice in the applications where high efficiency is not a concern but low cost is important.
- The typical efficiency of an amorphous silicon PV module can be around 6%.
Hybrid Silicon PV Module
- The Hybrid Silicon PV module is the combination of single crystalline silicon that is surrounded by thin layers of amorphous silicon.
- The combination of single crystalline silicon and amorphous silicon provides excellent sensitivity to indirect light or lower light levels.
- This type of silicon PV module has the highest level of the conversion efficiency of about 17%.
How solar module works
A standard solar module consists of a layer of silicon cells, a glass casing, a metal frame, and wiring to allow the current flow from the silicon cells. The Silicon has conductive properties that allow it to absorb the sunlight and convert it into electricity.
When the light comes into contact with the silicon cell, it sets electrons into motion and initiates the flow of electricity. It is called “Photovoltaic effect” and describes the general functionality of solar module technology.
The working of a Solar module can be described in the below step-by-step procedure.
Step 1 – The Silicon cells absorb solar radiation, which is sunlight.
Step 2 – The electrons begin to move when the sun rays interact with silicon cells.
Step 3 – these moving electrons cause the flow of electric current that is captured by the nodes and wiring in the solar panel.
Step 4 – The wires then feed this direct current to a solar inverter in order to convert it into the alternating current electricity.
Components of Solar Module
The solar module consists of various components
Module Mounting Systems
The energy output of the solar panel depends on the mounting structure. The PV cells must be mounted on a stable and durable structure in order to support the array and withstand the extreme weather conditions.
One of the most used methods to install is the rack mounting method. It is an easy, durable and versatile method.
It is one of the most essential parts of solar panels. The combiner box is the electrical enclosure that allows multiple panels to be combined in parallel.
From the combiner box, you can run one positive and one negative wire to the charge controller. The combiner box also houses series string fuses or circuit breakers.
Solar charge controllers
Every solar panel with batteries should have a charge controller. The charge controller regulates the amount of current the photovoltaic modules feed into a battery bank. The main function of solar charge controllers is to prevent overcharging of batteries.
The two main types of charge controllers are Pulse Width Modulated (PWM) and MPPT.
The PWM technology is commonly used on the smaller solar arrays and is one of the older technologies. The MPPT charge controllers are capable of tracking the maximum power point of a solar array and can deliver 10-25% more power than the PWM controller could deliver for the same array.
The MPPT charge controllers also have the ability to accept higher voltage from the solar array.
Batteries for solar panels
The batteries for solar panels store the electrical energy. There are three types of batteries that are most commonly used. They are:
- Flooded Lead-Acid Batteries
- Sealed Absorbed Glass Mat Batteries
- Sealed Gel Cell Batteries
The solar inverters convert the direct current generated by the solar modules into the alternating current that is the electricity, which is used by the households.
There are generally two types of inverters, they are:
- One inverter for all modules
- Each inverter for each module
Dc and AC disconnects
The AC and DC disconnects of the solar panel are the manual switches that hold the capability of cutting off the power to and from the inverter. Some of the modules have these disconnect switches integrated into the structure.
These switches are used by service personnel or authorized person to stop power from a renewable energy system from reaching the inverter. The disconnection prevents the current from going beyond the disconnected point to a utility grid or damaged component.
The solar module includes various other components as well that connects all parts of the system safely and securely. The other components are cables, connectors, conduit, and brackets. All these are the essential parts and tools that are involved in the proper installation of a safe and effective solar panel.