Solar edge vs enphase

[bonaire]

Thanks for the advice.

Yes we have different shading throughout the day and also different roof spaces. The west roof area is far smaller than the north. The shading comes from tall trees to the North East to East and then trees in the West in the afternoon (but the west ones I can prune to stop their shading).

And sorry for my ignorance but why micro's over optimizers?

You really don't need micro-inverters. Shading is a big problem with the value of solar entirely. How bad is it? enough to cover a few modules for many hours? One hour?

I suppose shading is primarily a problem with low sun in the winter but not in the summer?

I want to show you how to use multi-MPPT string inverters for a similar benefit. If you have two arrays you can get two smaller inverters. I use PowerOne Aurora inverters. Each has two MPPT controllers within each. I have 32 modules making up two arrays (both facing South in the northern hemisphere). In your case, your two arrays could be mounted on separate roof angles, using two 3.6 inverters, you could endure shading if wiring was done such that the lower modules and upper modules in each array plugged into each separate MPPT controller in each inverter. The price would be roughly the same or lower than micro-inverters.

Once you have shading over a small part of all the lower level modules, neither micro-inverter nor string inverter is going to win-out. The group of cells will just produce a lowly amount. You might get a few more Wh a day with micro-inverters as the early part of the shading comes in. But that is pennies per day.

Micro-inverters do not really "draw in the sun" when shaded. they produce very little of course when the module is obscured by shade from trees.

Talk to a local installer who can show the variations between installation methods. A 290W or 300W module can perhaps fully produce using a string inverter during peak sun but would be clipped at 250W with some of the micro-inverters. Except for the PowerOne 300W micro-inverter.

My system is much like this:

XXXXXXXX - - inverter 1 mppt 1 \ .
YYYYYYYY - - inverter 1 mppt 2 / \ ....... LINE OUT
XXXXXXXX - - inverter 2 mppt 1 \ ./
YYYYYYYY - - inverter 2 mppt 2 /

If Module set Y on either inverter is shaded, the X line of modules is producing fully and the minor output from Y is still collected. Unlike a single inverter with one large input and merged strings.

[perch]

Thanks for the advice.

Yes we have different shading throughout the day and also different roof spaces. The west roof area is far smaller than the north. The shading comes from tall trees to the North East to East and then trees in the West in the afternoon (but the west ones I can prune to stop their shading).

And sorry for my ignorance but why micro's over optimizers?

[inetdog]

Hi Guys,

New hear and trying to learn as much as possible before committing to a system. So thanks for any advice or info.

Basically I am in the same boat with shading. Over here in Australia we don't have the Enphase M250's yet. Apparently they won't be here for 3-4 months at the earliest which will be winter for us.

We want to install a 7.25kw system with two arrays of approximately 13-14 x North roof and 11-12 West roof. We are thinking of using either LG 300 or 290 Mono X Neons.

Basically what I am hoping is the people can give me some advice on whether to wait for the Enphase M250's or go the SolarEdge optimizer route.

I have done as much research as I can but cannot find any definitive answer on whether

a) microinverters are better than optimizers or vice versa or

b) Would the Optimizers be a better choice over M250 on the LG panels? or would the Enphase inverters be a better choice?

Thanks

If your biggest concern it the North versus West array, without any partial shading within each array, then you could even put the same number of panels on each roof and parallel them into one MPPT input.
But if you have partial shading, varying throughout even the parts of the day near noon, then micros would probably be the better way to go. And at a minimum you would need two MPPT inputs worth of string inverter.

If all of the panels in each array are in series, then shading will not be as overwhelming a problem. But if you have two or more strings in parallel, you need to look harder at the timing and effect of shade.

[perch]

Hi Guys,

New hear and trying to learn as much as possible before committing to a system. So thanks for any advice or info.

Basically I am in the same boat with shading. Over here in Australia we don't have the Enphase M250's yet. Apparently they won't be here for 3-4 months at the earliest which will be winter for us.

We want to install a 7.25kw system with two arrays of approximately 13-14 x North roof and 11-12 West roof. We are thinking of using either LG 300 or 290 Mono X Neons.

Basically what I am hoping is the people can give me some advice on whether to wait for the Enphase M250's or go the SolarEdge optimizer route.

I have done as much research as I can but cannot find any definitive answer on whether

a) microinverters are better than optimizers or vice versa or

b) Would the Optimizers be a better choice over M250 on the LG panels? or would the Enphase inverters be a better choice?

Thanks

[russ]

Agree, but if I do have shade, I assume they are worth looking at? A guy on my roof said I have a couple of good spots where shade value are 92-95%, but others down into the 80s.

You don't have a small shade problem - you have a major shade problem.

[Naptown]

Agree, but if I do have shade, I assume they are worth looking at? A guy on my roof said I have a couple of good spots where shade value are 92-95%, but others down into the 80s.

in your case it is worth your while to look at both types.

[lalaw]

If you don't have a shade problem they are a waste.

Agree, but if I do have shade, I assume they are worth looking at? A guy on my roof said I have a couple of good spots where shade value are 92-95%, but others down into the 80s.

[russ]

+1, I have been looking at both of these products. Seems like the folks on the forums have some disdain for enphase due to some changed terms on their warranty (not covering labor) and slow responsiveness to replacing failed units.

re: Solaredge, seems like not enough history for people to speak confidently (although the handful of people I've read comments from seem to like them)

Anything I'm missing?

If you don't have a shade problem they are a waste.

[lalaw]

Would love to get any update from this topic especially with respect to enphase M250 vs. Solaredge

+1, I have been looking at both of these products. Seems like the folks on the forums have some disdain for enphase due to some changed terms on their warranty (not covering labor) and slow responsiveness to replacing failed units.

re: Solaredge, seems like not enough history for people to speak confidently (although the handful of people I've read comments from seem to like them)

Anything I'm missing?

[grkmec]

Would love to get any update from this topic especially with respect to enphase M250 vs. Solaredge

[chrissilich]

Go for 50% of each and let us know !

Ha! Anyone volunteering to fund this experiment?

*crickets*

*crickets*

[vtkahns]

Good luck

So it sounds like they're pretty neck-a-neck on output for the 235-260w panel range. In that case, I'd say Enphase wins on ease of install (no string sizing) and warranty. Thanks for your input SoCalsolar and vtkahns.

I just wish the new Helios Solsimple all-in-one panels had a more competitive price, because that seems like a real winner.

Not aware of any string sizing issue with solaredge.. .. think it takes up to 28 or something ( i have only 18 so it was no issue ) .. as long as the inverter you mate up to has >= the capacity of those panels... No need to throw away power.

My configuration rarely gets me 240W out of my panels.. only in a very crisp.. sun / cloud situation and those spikes are short lived. They can go as high as 5000W where my inverter will stop them... but my system at STC only does 4300 W.

If I get to 4000W, I'm happy.. usually more in the 3-3.3K range all summer long due to heat..

I wish there was a head to head system split down the middle. 1/2 with one type.. 1/2 with another type.. so one could really see if there is a long term difference one way or another.. Go for 50% of each and let us know !

Vtkahns

[chrissilich]

So it sounds like they're pretty neck-a-neck on output for the 235-260w panel range. In that case, I'd say Enphase wins on ease of install (no string sizing) and warranty. Thanks for your input SoCalsolar and vtkahns.

I just wish the new Helios Solsimple all-in-one panels had a more competitive price, because that seems like a real winner.

[SoCalsolar]

1 consideration is the PTC rating

PTC rating plays a part here and it varies from panel to panel. A 250w panel will produce 250w in a laboratory (STC rating) but outside on a roof top a more accurate measurement would be PTC. PTC regularly runs about 87-92% of STC. 250w panel would almost always have a top end production at 218-230w and less as the years pass. A 240w panel would usually be between 209-221 less as the years pass. Can laboratory conditions exist on your rooftop? Sure but it will not only have to be the correct temp but right time of day/season for the sun angle etc. In my opinion a 240w panel is the highest I will combine with micro inverters. If you are basing your decision on cost/production then it gets a bit more murky.

[chrissilich]

People I know with the Enphase 215s see them clip at 225W.. The argument is that .. sure.. they clip now.. but as panels degrade.. will less so.. plus.. only clip on cold days when your output can get above 225. Their power curves are broader approaching that clipping so its not like the panels higher than 225 are completely wasted.

So would I be correct in saying that a 250w panel connected to an enphase 215 on a perfect day would generate 225w, while a 250w panel as part of a SolarEdge system would generate about 250w? In my future 24 panel system that would be a difference of about 600w. I'm still torn.