victron views on MPPT

[pianotuna]

This seems to be a "good read".

mppt from Victron

And a White Paper from the same source.

[JiminDenver]

So I called the guy with my new panels and asked that since they can make them any color, does a lighter color produce less heat. He said no and the only difference they noticed is the very dark colors like purple or dark green produced less power but that was all. So getting custom white panels will not help with the heat issues.

[SkiSmuggs]

Nice! Hadn't thought of doing series/parallel for the best of both worlds.

[pianotuna]

Hi Ski,

I have four Unisolar US-64 panels wired in series/parallel with a nominal input voltage of 33 to a Blue Sky (not Victron) 3024di controller. Total is 256 watts.

SkiSmuggs wrote:
Pianotuna, what setup did you use?

[ken_white]

This link has some good information as well -> Morningstar

[brulaz]

BFL13 wrote:
PT, they claim exclusivity, but ISTR the other MPPT makers also have current limiting MPPTs, and suggest taking advantage of that by over-panelling to get more AH. The math says the all-day AH haul is greater despite the mid-day clipping.
...

Agree. Fair amount of self-promotion there. Don't think my 30A Rogue will blow up on a sunny day if I boost the panel wattage from 390W to 590W.

Better/more light harvesting (love that word in this context) in low-light conditions is what it's all about.

[SkiSmuggs]

Pianotuna, what setup did you use?

[Shadow_Catcher]

Morningstar has a similar white paper and it bring up the value of a high voltage panel and MPPT controller. Certainly our results bear out the value.

[pianotuna]

Hi,

From what I could glean from reading MPPT goes hand in hand with using higher voltage. If you can't do that then PWM appears to me to be better in small installs.

At the same time my own personal results are outstanding, so I would probably do as I did again.

[BFL13]

Salvo wrote:
Didn't we just go through all of this?

http://forums.woodalls.com/index.cfm/fuseaction/thread/tid/28120645/srt/pa/pging/1/page/1

My memory is good, but it is short. So no harm done. 🙂

[Salvo]

Didn't we just go through all of this?

http://forums.woodalls.com/index.cfm/fuseaction/thread/tid/28120645/srt/pa/pging/1/page/1

[wa8yxm]

Thank you ... Thanks to those documents I now understand the difference in the controllers way better than five minutes ago..Thanks.. Good info to have.

[BFL13]

PT, they claim exclusivity, but ISTR the other MPPT makers also have current limiting MPPTs, and suggest taking advantage of that by over-panelling to get more AH. The math says the all-day AH haul is greater despite the mid-day clipping.

The whole MPPT vs PWM temperature thing drives me crazy because mine follows that trend, but my PWM results exceed the MPPT results at panel 51C, not the 70C claimed in the blurb. They say they just become about equal. I don't understand this. I don't have anybody else's numbers to compare with mine to see if my set-up has a problem, or if they just won't admit that sometimes PWM does better even at 25C ambient! More testing is needed this summer to solve this! 🙂

I don't think Vancouver Island at 25C ambient in July is the Tropics!
(Although it might seem so now in March compared with Back East! 🙂 )