Solar panels produce direct current (DC) which can conveniently charge a battery since batteries are charged with DC. But it is not advisable to connect solar panels directly to the batteries because when the batteries are fully charged, the solar panel will not know so it kept charging the batteries, thereby damaging the batteries.
Without a charge controller, the DC generated by the solar panels is continuously passed on to the batteries. If this conditions continuous at in the case without the charge controller, the batteries swells due to over-charging and eventually end up damaged.
So to avoid this, we make use of the solar charge controller. The solar charge controller is a very smart device which knows when the batteries are fully charged and cut off charging current to the batteries thereby protecting the batteries.
Also in the case of a Maximum power point tracking (MPPT) charge controller, it performs a dual purpose apart from protecting the batteries from overcharging; it also protects the batteries from undercharging when the DC from the solar panels is not sufficient to charge the batteries as fast as expected.
A solar charge controller is fundamentally a voltage or current controller to charge the battery and keep electric cells from overcharging. It directs the voltage and current hailing from the solar panels setting off to the electric cell.
Generally, 12V boards/panels put out in the ballpark of 16 to 20V, so if there is no regulation the electric cells will be damaged from overcharging. Generally, electric storage devices require around 14 to 14.5V to get completely charged. The solar charge controllers are available in all features, costs and sizes. The range of charge controllers are from 4.5A and up to 60 to 80A.
Types of solar charger controllers:
There are two different types of solar charge controllers, they are:
- PWM (pulse width modulated)
- Maximum power point tracking (MPPT)
PWM (Pulse width modulated): The pulse width modulated (PWM) charge controller is a type of solar charge controller that slowly reduces the charging current to avoid overheating the battery after it has reached the regulation setpoint. At the same time, the system continues to send the highest amount of energy over the shortest period of time, which results in rapid charge and high efficiency. Essentially, a PWM charge controller helps to increase charge acceptance of the battery while maintaining high battery capacity for a longer period of time.
Maximum power point tracking (MPPT): The MPPT solar charge controller is the most sought after in the industry today. These controllers truly identify the best working voltage and amperage of the solar panel exhibit and match that with the electric cell bank. The outcome is extra 10-30% more power out of the sun when compared with the PWM controller.
In general, the importance of a charge controller in the generation of electricity through the sun cannot be over emphasized. Selecting the best charge controller for your installations is very important as this can make or mar the entire system. Join Wavetra Energy Academy today to update yourself on how to select the best charge controller for your installations.