Solis v Solar Edge for 8KwP System

2nd_time_buyer

loofer said:

Screwdriva said:

I've just had to deal with my first inverter failure (my uncle's home, not mine) this past week. SolarEdge inverter failed the day after installation. SolarEdge were suspicious of incorrect installation but once that was proven not to be the case, they dispatched a spare inverter to us (despite having a national backorder of several hundred units) via Fedex from their factory in the EU. Installation takes place next week at no cost to us. 

I have never received any semblance of customer service from Chinese brands when it comes to warranty replacements, so thought I'd share this example for your consideration. I only recommend Enphase, SolarEdge, Fronius, Fimer or SMA inverters. 

Apparently they pay favourable rate to their approved installers to go out and reinstall/fix their kit under warranty.
Can see another reason why they push it.

I would recommend anyone thinking about installing Solaredge have a look at their Trustpilot Reviews and also the MC Electrical article and the comments underneath.

Obviously, these will tend to be biased towards people with bad experiences. But there do seen to be underlying issues.

ispookie666

You could consider Enphase micro inverters.  Only a few us on here who peddle them.  
I am a repeat customer, my original system was installed in 2015.  

On a long enough time line all inverters fail!

jcontest

I would opt for a simple string inverter personally. (The Solis, SMA if possible)

I would think your not likely to see any extra real output from microinverters or the optimisers. (read, perhaps 1-2%)

My system is 11 years old and has the original string inverter, Sunways (was German, now China, I wouldn't buy said brand now).

This is all my take but...

String Inverter

(-)Expensive to replace, (-)Single point of failure for whole system, (-)No Panel Level Monitoring

(+)Readily Available to purchase, (+)Located somewhere easy to get to if you do need to replace it

Microinverters

(-) More expensive to install, (-)Difficult to replace as it will be located under the panel, this could make it expensive in the long run

(+)Panel level monitoring, (+)Single panel failure may not hinder output - not likely a issue, (+)Future upgrades or Mismatching of panels are not going to be a issue

SolarEdge Optimiser + SolarEdge String Inverter

(-)Possitle high Downtime-you may need to wait for RMA product to get back up and going, (-) Possible single point of failure for whole system, (-) More expensive to install, (-)Difficult to replace as some will be located under the panel.

(+) Panel Level Monitoring.

I may just be old and grumpy.  But I would avoid SE unless you have a shady or mixed (more than one install direction) design.

Personally I Love the idea if Microinverters (and perhaps to that point SE) but scaffolding and RMA times to get something fixed/changed vs my inverter going dead and having someone go into the loft and just put a new one on the wall.. For me the choice is simple.  If it was a ground-based install I would probably go the extra just for the Panel Monitoring.

Exiled_Tyke

jcontest said:

I would opt for a simple string inverter personally. (The Solis, SMA if possible)

I would think your not likely to see any extra real output from microinverters or the optimisers. (read, perhaps 1-2%)

My system is 11 years old and has the original string inverter, Sunways (was German, now China, I wouldn't buy said brand now).

This is all my take but...

String Inverter

(-)Expensive to replace, (-)Single point of failure for whole system, (-)No Panel Level Monitoring

(+)Readily Available to purchase, (+)Located somewhere easy to get to if you do need to replace it

Microinverters

(-) More expensive to install, (-)Difficult to replace as it will be located under the panel, this could make it expensive in the long run

(+)Panel level monitoring, (+)Single panel failure may not hinder output - not likely a issue, (+)Future upgrades or Mismatching of panels are not going to be a issue

SolarEdge Optimiser + SolarEdge String Inverter

(-)Possitle high Downtime-you may need to wait for RMA product to get back up and going, (-) Possible single point of failure for whole system, (-) More expensive to install, (-)Difficult to replace as some will be located under the panel.

(+) Panel Level Monitoring.

I may just be old and grumpy.  But I would avoid SE unless you have a shady or mixed (more than one install direction) design.

Personally I Love the idea if Microinverters (and perhaps to that point SE) but scaffolding and RMA times to get something fixed/changed vs my inverter going dead and having someone go into the loft and just put a new one on the wall.. For me the choice is simple.  If it was a ground-based install I would probably go the extra just for the Panel Monitoring.

I'm very happy with my SE system.  But have to agree with you all the way on this.  Unless you really need it, it really isn't worth it.  

I have panels on 3 different orientations and have 2 different pitches on one orientation.  There really was no other option for me. 

elrao

Have had a price with micro inverters, was actually cheaper than the price with the Solis (different installer and smaller 385w panels, so about 4% less rated power).

Same people have come in cheaper with the Solis though too.

Unfortunately they are £1k more on the Tesla battery, so all levels out.

It's all one roof, facing same direction with minimal shading.  So minimal benefit in that respect.  The Enphase peddler mentioned they are better in winter, as the Solis might not even "kick in"

jcontest

Been a while since I have looked at it all from a technical perspective.

I would say if it's all in the same direction with the same or no shading then expect no real difference.

If the panel isn't producing enough for the Solis then I am unsure why the salesperson would feel the panel would produce enough for a Enphase "edge" Microinverter + Enphase Inverter.

There was a time when non-working panels could become a energy drain, but (again, been a while for me) I think the bypass and blocking diodes make this a non-issue these days.

At the end of the day your getting something that is more efficent (It is, I will not lie) by (usually) dumping more money on it (long term and install usually).  Odd that a quote for Panels+Micro Inverters (£ per Watt) would be cheaper (£ per Watt) than Panels+String Inverter.  If I was being quoted a higher price for a lower capacity string system then I would likely go with the SolarEdge and take the maintenance cost risk, caveat emptor.

If you do go with something like Enphase or SolarEdge then I would offer this bit of advice, use the monitoring tools to check all the panels are working and do it regularly (If software doesn't do that automatically).  If my export light stops flashing I know my system is dead (single string) but a Microinverter or Enphase system would still show generation even if a large chunk of the panels have no output.

The other consideration is IF you plan on putting panels on other sectons of your roof down the road.  If that is the case then the string is likely not ideal - BUT - the SolarEdge can be a bad idea as they still connect in "strings" to the central inverter and there can't be huge differences between string outputs!