Enphase vs SolarEdge

[miimura]

The ~23kW system I'm currently working on is using 15.4kW of string inverters with some panels facing East and some facing West. Can't split inverter capacity like that with micros. The inverters will also be saturated from 11am - 4pm so any increased efficiency offered by optimizers would be lost.

When you do the East/West arrays, do you purposely put East panels on one MPPT channel and West panels on another MPPT channel on the same inverter to further broaden the output curve and increase inverter utilization? If you had two inverters and two equal arrays facing different directions, I would think the natural thing would be to put all of one array on one inverter. When overprovisioning the panels, it would seem that the mixed approach should work better.

 

[nwdiver]

When you do the East/West arrays, do you purposely put East panels on one MPPT channel and West panels on another MPPT channel on the same inverter to further broaden the output curve and increase inverter utilization? If you had two inverters and two equal arrays facing different directions, I would think the natural thing would be to put all of one array on one inverter. When overprovisioning the panels, it would seem that the mixed approach should work better.

The new SMA inverters actually have 3 MPPTs each. So between the 2 inverters there are 6 MPPTs total. Each string will be able to operate independently. Each inverter will have 2 West facing strings and 1 East facing string. Having one east and two west facing strings on each inverter should provide a flatter production curve with less clipping.

 

[Toumal]

I can't really say anything about Enphase, though my installer also advised against using per-panel microinverters. They are fully exposed to the heat and even though they are fully sealed, their lifespan is limited and they have to replace them much more often than they replace optimizers.

I'm running an SE7K with P300 optimizers, we have three systems in the family and nobody has had any issues yet. I'm also running 3 Victron Multigrid and 3 x 10 kWh BYD B-Box LV for storage, which works "mostly". I have a long history of back and forths with Victron and while they were able to fix one issue with a firmware update, I still have a problem causing around 20% of the energy being wasted in pointless charge/discharge oscillations.

So Solaredge I can recommend so far. Victron, not happy yet. Still hoping they'll fix it, alternatively I might try and replace their regulation logic with my own.

 

[ai4px]

When you do the East/West arrays, do you purposely put East panels on one MPPT channel and West panels on another MPPT channel on the same inverter to further broaden the output curve and increase inverter utilization? If you had two inverters and two equal arrays facing different directions, I would think the natural thing would be to put all of one array on one inverter. When overprovisioning the panels, it would seem that the mixed approach should work better.

I think it best for shading to keep each array on one MPPT input. SMA's have 3 MPPT inputs, South, West, and East.... no need for North, eh?

 

[winfield100]

I think it best for shading to keep each array on one MPPT input. SMA's have 3 MPPT inputs, South, West, and East.... no need for North, eh?

how about 5 sides?
".. 11.1-kW photovoltaic (PV) system made of 40 single-crystal silicon panels on the roof and about 250 thin-film copper indium gallium diselenide (CIGS) panels on the sides .." i recall abt 19kW (Washington, DC, USA mall) (800sq ft living space i think)
The louvers on the windows all had small PV panels individually wired ("it's great to have free labor grad students")
DOE Solar Decathlon: 2009 Team Germany

 

[nwdiver]

I think it best for shading to keep each array on one MPPT input. SMA's have 3 MPPT inputs, South, West, and East.... no need for North, eh?

The primary benefit to having a MPPT per string is that you can have an array with any number of panels so the design is MUCH more flexible. With 1 MPPT all strings need to be the same length. A friend has a 13kW array with 44 panels but his shop could fit 9x5. So one is there just for aesthetics . The next big benefit is shading. With 4 strings on 1 MPPT you can lose ~10% production by shading 1 panel (~3%). You also eliminate the need for a combiner box or fuses. IMO string level MPP is the optimal cost-benefit arrangement.

 

[Hank42]

I have two proposals from the same company. One uses SolarEdge with optimizers, at $2.50 per watt, and another uses Enphase IQ7 microinverters, at $2.80 per watt.

The installer says that Enphase IQ7 is more efficient and generally produces more power than SolarEdge. They also have a better warranty. And they might release the new IQ8 microinverter which may allow the system operate during the day without a battery.

Do you have any experiance with Enphase vs. SolarEdge? Is it true that one produces more energy than the other? Is there any other pros/cons?

I use Enphase brand microinverters (IQ6) - they have a neat web app that lets you view detailed statistics such as energy usage /produciton as well as lifetime output per panel - useful for warranty etc.. Also, the time-lapse feature is pretty neat - helps identify un-anticipated shading.

It's not really all that useful, but it's included in the cost.

I've been happy with Enphase, but from what I hear about SolarEdge, I don't think you can go wrong with either.

 

[Toumal]

Heh... this looks almost exactly the same on Solaredge. They seem to be taking "inspiration" from each other

 

[supratachophobia]

Heh... this looks almost exactly the same on Solaredge. They seem to be taking "inspiration" from each other

View attachment 372324

SolarEdge with consumption monitoring is amazing. Great info, great interface

 

[ai4px]

The primary benefit to having a MPPT per string is that you can have an array with any number of panels so the design is MUCH more flexible. With 1 MPPT all strings need to be the same length. A friend has a 13kW array with 44 panels but his shop could fit 9x5. So one is there just for aesthetics . The next big benefit is shading. With 4 strings on 1 MPPT you can lose ~10% production by shading 1 panel (~3%). You also eliminate the need for a combiner box or fuses. IMO string level MPP is the optimal cost-benefit arrangement.

I’m puzzled.... 45 would be 15 panels times 3 MPPT strings.... why only 44? At first I thought it might be a VOC thing, but again, 44 not divisible by 3.... 44 into 2 MPPT strings seems too much, around 880v per string. 15 x 40v is 600 per string.... granted you should stay around 525v, but OK.... So why 44 panels and one for aesthetics?

 

[nwdiver]

I’m puzzled.... 45 would be 15 panels times 3 MPPT strings.... why only 44? At first I thought it might be a VOC thing, but again, 44 not divisible by 3.... 44 into 2 MPPT strings seems too much, around 880v per string. 15 x 40v is 600 per string.... granted you should stay around 525v, but OK.... So why 44 panels and one for aesthetics?

That system has an older inverter with 1 MPPT so all strings had to be of equal length. 15 would exceed 600voc (45v panels). 9 and voltage would be too low. So it's 4 strings of 11. If it had 4 independent MPPTs we could have done 11,11,11,12.