outback solar mppt controller

Golden_HVAC wrote:
If I wanted to replace my 415 watt solar system, I would be buying 140 watt solar panels from this place for around $229. SunElec.com

And I would be buying $14 PWM controllers. AliExpress.com and then search for PWM 20 amp controller.

They way I figure it, you are much better off spending the money on solar panels than on a very expensive MPPT controller.

That said, I did buy a Solarbost 50 amp controller back in 1999. Back then, it cost $430 to buy a 120 watt solar panel, and installing more solar panels would have been more expensive than changing to the MPPT controller.

Now MPPT controllers are much less expensive (I think I paid over $300 for mine in 1999). But PWM Controllers are really cheap.

So lets look at two theoretical systems.

Say you pick 3 each 100 watt panels at say $200 each, and a $150 MPPT controller.

Or you could pick 3 each 140 watt panels for $229 each and a pair of $14 controllers. I would guess that the cheap controllers will put more power into the battery for about the same cost.

Good luck with your solar system.

Fred.

for most cases your right on for cost/$$/watt. And any more with the price of panels dropping, PWM controllers really do make a lot of sense, especially when one had to jump from a 15A MPPT to the next step up from morningstar. With the prices coming down on MPPT controllers it's at least something one can contemplate. Especially when the MPPT in question will let one series 3 maybe panels. Some of the earlier inexpensive ones really would only let you series two panels.

In my case, we have portable panels, often needing to place them 100-150 ft away from the trailer. And camp for a week or more and want batteries charged. Now panels aren't exactly light weight, or small, so panel size and weight to lug around has some influence in my case, and minimizing I2R cable loss with the long cables as well. not big, but every amp counts. Now it wasn't worth the price for the morningstar bigger controller in the past, but for $150, something I'd consider. And the morningstar 15A doesn't go to waste since I'd put it on my smaller trailer that doesn't usually need as much solar.


But yes, for most cases I'd agree with you that more panel amps and PWM controller is the better choice.