What's the difference between MPPT and PWM solar charge controllers?

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Understanding MPPT Charge Controllers MPPT charge controllers are designed to extract the maximum amount of power from solar panels by constantly adjusting to the optimal voltage and current. This is achieved through advanced microcontrollers that continuously monitor the solar panel’s performance and adjust the charge controller’s settings to achieve the highest possible efficiency. MPPT charge controllers are ideal for systems with a high voltage difference between the solar panel and battery bank, such as those with 12V or 24V solar panels and a 48V battery bank.
Key Benefits of MPPT Charge Controllers When selecting a charge controller for an RV solar system, consider the following: for systems with a small solar panel array (less than 500W), a PWM charge controller may suffice. However, for larger systems (500W and above), an MPPT charge controller is necessary to ensure maximum energy harvesting. For example, a 500W solar panel array with a 48V battery bank can see a 25-30% increase in energy production with an MPPT charge controller compared to a PWM charge controller.
Technical Considerations When choosing an MPPT charge controller, consider the controller’s efficiency rating. A high-efficiency MPPT charge controller (95% or higher) will ensure that the maximum amount of energy is extracted from the solar panels. Additionally, look for controllers with built-in temperature compensation and high surge current handling capabilities to ensure reliable operation in extreme conditions. A good rule of thumb is to choose a charge controller with a higher surge current rating (at least 50A) to accommodate the high current spikes during charging.