MPPT solar charge controller: An overview of the incredible technology

Just like any other system that stores energy in a battery, a solar panel system also uses a device that manages and controls the energy flow.

11:23 29 March 2021

This device is called the solar charge controller. Despite choosing the best batteries, there is always a chance of overcharging. For that reason, solar charge controlled is imperative for these systems. A Victron Solar Controller at Offroad Living effectively regulates the charging and discharging cycle of the solar batteries.

 

Two variants of solar charge controllers are available in the market, each having its pros and cons. Here we provide a detailed description of the MPPT charge controller to help you make an informed decision while choosing one for your system.

 

• Introduction to MPPT solar charge controller

 

MPPT is also called the Maximum Power Point Tracking controller. As the name suggests, these controllers are known to track the power to the maximum point. It quickly charges the battery and ensures that the load is provided with the maximum current. It tracks the power for maximum power-point. In simple terms, it ensures that regulates the voltage to its ideal value at which the load receives the maximum power with minimal voltage loss.

 

Oftentimes, it is observed that the maximum power point varies due to factors such as temperature, the workmanship of the device, and light conditions. MPPT allows to regulate the device resistance and maintain peak power voltage of the solar device despite these factors.

 

• How does it work?

 

The basic property of charging and discharging a battery states that the voltage of the battery changes with the current content it has. When the current flows from high to low potential, you can increase the flow of current by varying the voltage by greater differences. Meaning, the higher gradient in the change of voltage results in an increased flow of current and thus leads to a higher voltage of the battery.

 

The same principle is used by MPPT to achieve the peak power voltage. This is accomplished in solar batteries in two ways, using increased panel voltage and using battery voltage.

 

• Delivering maximum power using increased panel voltage

 

The charging of a battery depends upon the output voltage of a solar panel which varies with several external factors including weather. The output voltage would be more on sunny days and lesser on cloudy days. Unlike other controllers, MTTP controllers can adjust the voltage to current ratio and deliver a boost of current during the charging of the battery.

 

• Delivering maximum power using battery voltage

 

MTTP controllers are capable of introducing some resistance in the path of current thereby lowering the flow of current. This results in a boost of the battery voltage which is called maximum power point tracking. It can effectively deliver a boost of nearly 25% to 30%.

 

• Optimum battery charging by combining techniques

 

Ideally, MPPT utilizes both of the aforementioned principles to deliver maximum power. These are pre-programmed for the set-points which are also adjustable and can be altered and reset according to your needs. Given its merits of a standard controller, most people choose to invest a little more and go for MPPT controllers for solar panels.