Benefits of Solaredge vs. string inverter for non-shaded

[sensij]

It would be interested to swap the arrays to the inverters and see how identical your two arrays are. How do you know they are identical? Modules generally are -0, +5%. Can you post a photo of your arrays?

Great idea, except you can't swap a SolarEdge inverter with a standard string inverter without handling every panel to remove the optimizers from one array and install them on the other. Solarix has demonstrated a lot of knowledge and experience in this forum... I'd take him at his word that the arrays are identical in the most obvious ways.

[foo1bar]

Who's going to maintain and service the equipment ? Will it happen ?

I'm not anticipating much in maintenance and service.
Any issues that are related to warranty (ex. inverter fails) I expect the installer to handle.
I would guess with 10+ inverters that there will be one infant mortality in the first 2 years.

The only other thing I expect is that occasionally the panels may benefit from being washed. (It often won't rain from May until Oct.)
I expect that to be done by facility staff. (Probably will use a hose and something like the "Mr. Clean AutoDry Car Wash System" for the final rinse)
And at that time I'd expect they'd look for any wires that had slipped out of the cable management.

What other things do you think we should anticipate?

[wes@SH]

Solarix, uou have two identical arrays on the same roof face? If you found identical panels as your original array connected to the xantrex, the older panels would have degraded and not be efficient as the newer ones hooked up to the solaredge inverter. Possibly, you have installed something incorrectly on the newer system, or your original system took the best south facing roof and your newer array is pointed in a different direction.

There is always shading, even if it is only from the sky. If it was a residence, I would want SE even without tree shading. You are looking at $12,200 just in optimizers; a rough comparison might be $kWH x 50,000 x .001 x .02 x 4.5 x 365 x 25, even at .05 it probably doesn't add up with risk of failed components and lost time. Also, are you choosing to do a 160 panel E/W split on flat roof over pure south, or is this a very large gable?

[rsilvers]

On my house I run 2 identical arrays, one with a Solaredge system, one with my old Xantrex inverter. There is no shading. The Xantrex inverter consistently outproduces the SolarEdge by a slight amount every day.

It would be interested to swap the arrays to the inverters and see how identical your two arrays are. How do you know they are identical? Modules generally are -0, +5%. Can you post a photo of your arrays?

[sensij]

I'm a big fan of SolarEdge; I've learned a lot about PV from studying the data that the system provides. I am skeptical of Solarix's claim that the Xantrex inverter actually outproduces the SolarEdge system... the numbers are close enough to be within measurement error of each other, and at that level, there are lots of other factors that could be contributing to the results. Despite that, the point still stands; the difference between the system types in an unshaded array is very small.

Even though I enjoy having my SolarEdge system at home, I am also involved with designing what may be a several hundred kilowatt system for work. It is unshaded, and I've strongly advocated against SolarEdge or any other panel level electronics. At that scale, any data needed to troubleshoot that is not provided by the inverter itself can be inexpensively added by a 3rd party monitoring system. It won't narrow it down to the panel, but in the rare event that a panel or circuit does fail, the problem can be isolated to a small enough area that it can be tracked down quickly.

[J.P.M.]

Who's going to maintain and service the equipment ? Will it happen ?

[azdave]

Totally agree on the "reliability vs efficiency" cautions.

Reminds me of the newer A/C units that use variable speed (ECM) motors to reach the last few tidbits of efficiency.
After having three expensive motor/controller failures in 8 years I've spent far more in repairs than I could have ever expected to save in electricity costs. I should have bought the "inefficient" single speed motor units and saved over $1000 and many nights of sweating it out waiting for repair parts to arrive.

[solarix]

On my house I run 2 identical arrays, one with a Solaredge system, one with my old Xantrex inverter. There is no shading. The Xantrex inverter consistently outproduces the SolarEdge by a slight amount every day. I was a big enthusiast of SolarEdge early on until I did this head to head comparison and discovered that their "up to 2%" here and "up to 2%" there claims did not pan out. Plus I had a horrendous failure rate (this was on their earlier model). My advice with inverters is: Like in real estate, what matters is Reliability, Reliability, Reliability. All the shade mitigation, per-panel-optimization, and panel monitoring is minor compared to getting the expected life out of your equipment. String inverters give good performance, are a lot more serviceable, and are more reliable than electronics on your roof. SMA is the only brand I haven't had reliability problems from.

[foo1bar]

I am part of group reviewing proposals for a ~50kW system.

2 of the reasonable proposals are using Solaredge (For one of them the sales guy says the 20kW inverter - but I don't think that works for a 208V 3-phase system)
The other slightly cheaper proposal uses a string inverter (HiQ inverter - will be mounted on roof)

I would like to use Solaredge - I like the per-panel monitoring. And I like the benefits from per-panel MPPT.
But I'm not sure I could justify the additional cost.
If you were doing the cost-benefit analysis, what benefits would you say there are for a Solaredge system vs. string inverter?
I'm not sure whether it's a 2% additional kwh produced because of per-panel MPPT - or a 5% benefit.
BTW - this will be ~25kW facing East, ~25kW facing West.