What is the difference between PWM and MPPT solar charge controller

Solar controller

What is the difference between PWM and MPPT solar charge controller

June 3, 2021
4 mins to read

Seeing that solar energy is the new trend these days, I am sure you must be curious about solar charge controller. But before moving to PWM and MPPT Solar charge controller, let me give you a brief idea of what it is meant for.

Solar charge controller, in layman terms, can be thought of as a regulator or a controller that prevents the solar panels from overcharging. These controllers are not anything new in the market. As a matter of fact, they have been here since the very existence of solar panels.

In earlier days, the method was more of a simpler approach. The controller started or stopped the power connectivity between panels and batteries as per requirement. But now we’ve moved into a new era, right? So things were bound to change even for these humble solar charge controllers as well.

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Since we were presented with the mighty PWM and MPPT solar charge controllers, they have dominated the market ever since. Now the question arises: “Which is better of these two?”Let's check out…

PWM stands for pulse width modulator that can be imagined as a switch being turned on or off at certain intervals as per the requirement. Now PWM solar charge controllers work in the same manner. The regulator connects the solar panel and batteries at varied time intervals. Let's see how:

If the solar panel is fully charged, the PWM controller will disconnect the batteries to keep it from overcharging. Also, this method makes sure that the solar panel is always charged at the standard voltage level.

Now coming to MPPT solar charge controllers. MPPT or maximum power point tracking solar charge controller is a more convenient and improved way to regulate the solar panels and batteries’ connectivity.

It uses digital electronic tracking to compare the output level of solar panels with the battery voltage. Henceforth, this gives the optimized voltage level at which the panel should be charged. Let's now summarise which is better for you.

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Cost

The cost of a PWM controller is one-third as compared to MPPT Controller, MPPT Controller is relatively an expensive one-time investment.

Size

PWM controllers are smaller in size going at most till 60 Amps. MPPT controllers are designed specifically to be large supporting bigger solar panels in an efficient manner.

Durability

In terms of their durability, PWM Controllers are more durable. MPPT controllers are more prone to breakage. Although, they come with a longer warranty period.

Market Appearance

PWM has been in the market for a long time and is therefore tried and tested. MPPT is relatively new but a raging trend in the market.

Limitation

It can’t be used with bigger solar panels (>60 panels) by PWM controller.The array voltage has to be at all times higher than the battery voltage with MPPT controller.

quick-guide-to-choose-the-right-charge-controller-for-your-PV-system

As we can see both PWM and MPPT solar charge controllers come with their own set of pros and cons, it varies upon the user and their requirement, which one they should purchase. Ideally, if your solar panel is smaller and to be installed in a low to humid climatic region, you can go for PWM solar charge controllers. Whereas, MPPT solar charge controller would be more effective if the weather is going to be cloudy/rainy and you require flexibility within your system.


It is also proven to be 30% more efficient.

In conclusion, if you have money to spare, go for solar panel with MPPT solar charge controller and you won’t be disappointed. Moreover, the aftercare support for this product is very reliable.