inexpensive panels

SJ-Chris wrote:

Tom_M wrote:
That controller is a PWM. You need an MPPT controller.

Is it truly REQUIRED? Or is it just a preference?

I understand that the MPPT controllers might be a little more efficient. But the system I'm creating is probably an overkill anyways for my needs so I'm not worried too much about squeezing out every bit of efficiency.

-Chris

MPPT is required if you are planning to use any panel over 17V with a 12V battery system.

Pretty much every cheap or low cost solar controller is PWM (Pulse Width Modulated) which are not designed to drop that 30V output of the panel to 12V..

MPPT controllers are much more expensive that PWM and GOOD MPPT controllers are even more expensive yet.

Hence a lot of your savings on that 250W 30V panel goes right out the door..

HERE is a Amazon search of MPPT controllers.

And looks like entry level MPPT starts at the $100 level.

I noticed one that was insanely cheap price, yeah, that one IS NOT MPPT once you start reading the information and reviews.

You have to shovel through a lot of marketing double speak and sometimes the lies to figure out if it is MPPT or not.

If you can find the manuals, read them before purchasing, you will need to make sure that the controller is able to take a higher voltage like 30V or even 60V and output 12V for a 12V battery.

So the reality is you spend $50 on a that panel, $100 on MPPT and we haven't even discussed the shipping which will be most likely better than $50 and if you are lucky the panel arrives in tact and working..

You can buy 2 100W 12V panels plus PWM controller at Amazon for around $200 and if you have Prime, might even be eligible for free shipping on top of that.. Pretty much makes that used panel a lot less of a "deal".