• Do I need a solar charger controller?

    Smart solar charge controllers are a critical part of solar installations. The only exception to needing a solar charger controller is if you have small panels smaller than five watts. The solar charge controller sits between the energy source and storage and prevents overcharging batteries by limiting the amount and rate of charge to your batteries. solar panel charge controllers also prevent battery drainage by shutting down the system if stored power falls below 50 percent capacity and charging the batteries at the correct voltage level. This helps preserve the life and health of the batteries. They also offer other essential functions, such as overload protection, low voltage disconnects, and block reverse currents.

  • What is the difference between MPPT and PWM charge controllers (MPPT vs. PWM)?

    There are two charge controllers to consider: Pulse Width Modulation controllers (PWM controllers) and Maximum Power Point Tracking controllers (MPPT controllers). PWM controllers are more basic in the sense that they drop the voltage coming from the solar panel(s) to the batteries. This drop in voltage equates to a loss in wattage, which results in 75-80% charging efficiency. MPPT technology “finds” the maximum operating point for the panels’ current and voltage under any given condition. MPPT charge controllers are actually 94-99% efficient with this method. This higher efficiency can help increase the life of your battery bank. MPPT solar controllers perform better in cold, cloudy environments. They are suitable for larger systems where the additional energy production is valuable. They perform best when the battery is in a low state of charge. MPPT solar charge controllers are also ideal for situations where the solar array voltage is higher than the battery voltage. The main drawback of using MPPT solar charge controllers is their cost. They are more expensive than PWM charge controllers. MPPT controllers cost between about $100 to $700.

  • What size charge controller do I need?

    Charge controllers are sized based on the solar array's current and the solar system's voltage. You typically want to make sure you have a charge controller that is large enough to handle the amount of power and current produced by your panels. If your solar system's volts were 12 and your amps were 23, you would need a charge controller with at least 23 amps. However, you need to factor in an additional 25% due to environmental factors. This brings the minimum amps that this charger controller must have to 28.75 amps. In this example, you would need a 12-volt, 30-amp solar charge controller.

  • Can you charge solar batteries without a charge controller?

    You don’t need a charge controller with small 1 to 5 watt solar panels. A charge controller is required if your solar battery system produces more than five watts of solar power or has more than 100 amp-hours of capacity.