# MPPT vs PWM charge controllers

## Question always comes up, is MPPT better than PWM?

Here is why...
(assuming perfect conditions)

### PWM

When you connect a PWM charge controller to a 250W solar panel charging a 12V battery, the controller puts out the maximum current the panel produces out, 8A in this case, but only takes 12V from the panel to charge the battery.

12V x 8A = 96W is what the controller puts out to charge the battery, while the panel is capable of 250W.

### MPPT

In this case the controller looks for the best power point from the 250W panel by sweeping the Voltage and Current lines from 0 to MAX and once it has found it, it starts to convert the MAX power into charging the 12V battery. 250W panel puts 30V and ~8A current out.

250W / 12V = 20A

MPPT controller will put out 12V and 20A of current into charging the battery, it takes 30V and 8A from the panel.

### At \$180 for a basic TS45A PWM charge controller, your charge current is 8A At \$350 for a Phocos MPPT controller your charge current is 20A

This means:

• You will spend ~3 times less time to charge the battery with an MPPT controller.
• You are spending less than 2 times on the MPPT controller.

You decide which one is the right controller for you.

# MPPT vs PWM charge controllers

## Question always comes up, is MPPT better than PWM?

Here is why...
(assuming perfect conditions)

### PWM

When you connect a PWM charge controller to a 250W solar panel charging a 12V battery, the controller puts out the maximum current the panel produces out, 8A in this case, but only takes 12V from the panel to charge the battery.

12V x 8A = 96W is what the controller puts out to charge the battery, while the panel is capable of 250W.

### MPPT

In this case the controller looks for the best power point from the 250W panel by sweeping the Voltage and Current lines from 0 to MAX and once it has found it, it starts to convert the MAX power into charging the 12V battery. 250W panel puts 30V and ~8A current out.

250W / 12V = 20A

MPPT controller will put out 12V and 20A of current into charging the battery, it takes 30V and 8A from the panel.

### At \$180 for a basic TS45A PWM charge controller, your charge current is 8A At \$350 for a Phocos MPPT controller your charge current is 20A

This means:

• You will spend ~3 times less time to charge the battery with an MPPT controller.
• You are spending less than 2 times on the MPPT controller.

You decide which one is the right controller for you.