Agree entirely except for MPPT efficiencies (isn't that a maximum efficiency rating? what's a typical range and what conditions do you need to stay near that max?) and the "not CC" ... DSSR20 simply passes amps from your panels (a CC source). Do the DSSRs regulate that current? No. Think that's all I was trying to say in reponse to the "not PWM-ish" reply.OK, so not CC
I was going to make a few more observations, but I see that Dacian has already made them in the comments in that youtube clip.
The only thing that I disagree with is his statement that a MPPT charger throws out 6% to 8% of the input power as heat. Unless you buy bottom shelf products that simply doesn't hold true. That could easily be over 80 watts. You'd need a really big heatsink to cope with that passively, but yet the heatsink on my passively cooled MPPT controllers does not become burning hot, which it most certainly would under that sort of power load.
Victron rates their SCCs as 98% efficient, ie dropping 2% as heat. Given the temperature rise I see with them, that is quite believable. The couple of Renogy (SRNE OEM) SCCs I have been testing lately fall into the same category.
Is it a revelation that MPPTs like a bit of headroom to charge a battery? No. It's stated in the manuals for decent ones, along with voltages required to start charging, and maintain charging once started. It's certainly something that has been mentioned on this forum several times. MPPT controllers really make the life of the system designer much easier and systems more flexible by removing the necessity to keep the array Vmp near battery voltage.
This is not to say there is anything wrong with Dacian's approach, it's just another option for people to consider, and that has to be a good thing.
So what's the point of all this heated agreement? I certainly didn't start this thread to convince anyone that one product is better than another. I started it because we've been dying for this kind of side-by-side. Why? Because I think there's a misconception that you need MPPT to sop up all the power you can out of your solar panels. In some cases you do, as the scenarios described above attest, but not all! You can absolutely design a system and get near or even better-than MPPT performance without having to buy one (or find a place to put it). Up to now, it's only been theoretical for a lot of us. Starting to get RW test results that bear it out is pretty damn cool.
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