real word test on my roof, 12 Sunpower 327 e-20 and 12 LG Neon 2 330w panels

[Floydturbo]

On 2/1/18 a local company in Sacramento installed 12 Sunpower e20-327-ac panels on my roof. Today on 3/3/18 I installed 12 LG Neon 2 LG330E1C-A5 on the my roof. The location and angle are essentially identical. This will be a good test of two of the best panels out there. The first day was rainy with on and off again sun. The Sunpower group produced 8.9kwhr and the LGs made 8.98 kwhr. Pretty amazing that the output is so close. I used Enlighten and Monitor.us.sunpower to determine the output.

[J.P.M.]

On 2/1/18 a local company in Sacramento installed 12 Sunpower e20-327-ac panels on my roof. Today on 3/3/18 I installed 12 LG Neon 2 LG330E1C-A5 on the my roof. The location and angle are essentially identical. This will be a good test of two of the best panels out there. The first day was rainy with on and off again sun. The Sunpower group produced 8.9kwhr and the LGs made 8.98 kwhr. Pretty amazing that the output is so close. I used Enlighten and Monitor.us.sunpower to determine the output.

This is going to be fun.

Although 1 cloudy day is certainly no smoking gun, after 4+ years of data gathering and comparison with other arrays around my neighborhood, I've been singing the mantra that Sunpower, while good stuff, will produce about the same annual output per installed STC kW as any panel of reasonable quality that's professionally installed by a knowledgeable vendor. If the inverter tech. is reasonably similar for your two systems, seems like you've got a decent method to compare a S.P. system to a non S.P. system. Any chance at folks here getting a look at daily or better output ?

FWIW, The 5 minute S.P. monitoring is usually pretty good, but mine is about 5 to 20 minutes or so off (behind) in timestep from actual clock time.

Given what I have from my S.P. array and lots of data from local PVOutput in addition to my neighborhood comparison stuff, and finding little difference in output per STC kW from any of them once adjusted for orientation from one array to the next, or to mine, yours will be a comparison I look forward to.

[solarix]

I've got the same thing going as I split my array of 20 Trina panels in two (four years ago) and one half is on the old Xantrex inverter and one half got a new SolarEdge inverter with optimizers. The SolarEdge does better starting in the morning, but the Xantrex consistently wins slightly by day's end. The panels are tilt rack mounted on a flat roof and there is no shade except the rows do shade each other a bit morning and evening.

[J.P.M.]

I've got the same thing going as I split my array of 20 Trina panels in two (four years ago) and one half is on the old Xantrex inverter and one half got a new SolarEdge inverter with optimizers. The SolarEdge does better starting in the morning, but the Xantrex consistently wins slightly by day's end. The panels are tilt rack mounted on a flat roof and there is no shade except the rows do shade each other a bit morning and evening.

With nothing different except inverters, any thoughts/SWAGs on why the inverters seem to be producing differently ? What's the approx. % diff. in production over a year ?

Thanx.

[ButchDeal]

With nothing different except inverters, any thoughts/SWAGs on why the inverters seem to be producing differently ? What's the approx. % diff. in production over a year ?

Thanx.

the rows shade each other.
The inverters are not only different but different tech with one having batteries to maintain and the other not
Also where is the monitoring coming from? there likely is also differences in the accuracy of the monitoring due to the multiple equipment on the bimodal side.

[littleharbor]

[QUOTE=ButchDeal;n372268]


The inverters are not only different but different tech with one having batteries to maintain and the other not


Xantrex has made grid only inverters for a long time, starting with simple 48 volt inverters, moving on to their GT models. Which Xantrex inverter are we talking about?

[J.P.M.]

the rows shade each other.
The inverters are not only different but different tech with one having batteries to maintain and the other not
Also where is the monitoring coming from? there likely is also differences in the accuracy of the monitoring due to the multiple equipment on the bimodal side.

I can understand inaccuracies or differences in monitoring, but neither Floydturbo's or Solarix' systems or posts have any mention of batteries. Sounds like they don't have any. Or are you writing that the inverters have batteries ?

The way I read it Floydturbo's systems were not shaded or perhaps - although very unlikely - shaded in the same way.

Maybe my assumption of no shading is incorrect for Floydturbo's systems and shame on me for a bad one with respect to Floydturbo's system(s), but I'm assuming that as an installer with what seems a fair amount of experience, Solarix knows the effects of shading and wouldn't waste his time or anyone else's time B.S.ing about it, particularly for the small differences he seems to be reporting or at least implying. A bit of morning and afternoon shading are probably not grossly significant and, as sounds to me from: "The rows do shade each other", are side/side and mostly south facing, the shading may tend to reduce output somewhat equally.

Maybe a bit more from Solarix on orientation and shading would help.

Pardon my ignorance, but what's the "bimodal side" ? And, in what ways would different characteristics of such a side affect the accuracy (and/ or I'd guess the precision ?) of what a monitoring system reports ?

Thanx.

[ButchDeal]

I can understand inaccuracies or differences in monitoring, but neither Floydturbo's or Solarix' systems or posts have any mention of batteries. Sounds like they don't have any. Or are you writing that the inverters have batteries ?

The way I read it Floydturbo's systems were not shaded or perhaps - although very unlikely - shaded in the same way.

Maybe my assumption of no shading is incorrect for Floydturbo's systems and shame on me for a bad one with respect to Floydturbo's system(s), but I'm assuming that as an installer with what seems a fair amount of experience, Solarix knows the effects of shading and wouldn't waste his time or anyone else's time B.S.ing about it, particularly for the small differences he seems to be reporting or at least implying. A bit of morning and afternoon shading are probably not grossly significant and, as sounds to me from: "The rows do shade each other", are side/side and mostly south facing, the shading may tend to reduce output somewhat equally.

Maybe a bit more from Solarix on orientation and shading would help.

Pardon my ignorance, but what's the "bimodal side" ? And, in what ways would different characteristics of such a side affect the accuracy (and/ or I'd guess the precision ?) of what a monitoring system reports ?

Thanx.

I guess a possibly bad assumption as xantrex makes primarily bimodal inverters now, so batteries would be involved there.
he did not specify how they were devised but my assumption would be that the optimized system would be used for the most shaded ( partially) rows and leave the least shaded rows on the unoptimized inverter.

[J.P.M.]

I guess a possibly bad assumption as xantrex makes primarily bimodal inverters now, so batteries would be involved there.
he did not specify how they were devised but my assumption would be that the optimized system would be used for the most shaded ( partially) rows and leave the least shaded rows on the unoptimized inverter.

I think we (or I at least) need some direction and info from Solarix as to orientation(s). If an array was split, I'd tend toward thinking (and perhaps incorrectly so) that the former single array was at one orientation or similar orientations, particularly with the as stated similar output. I see no compelling reason from what I read of Solarix' posts to think that one half of the original array is shaded more than the other half as you seem to be writing or implying.

I also see that I need some clarification from Solarix as to any storage capabilities in either current system and how such capabilities would affect array production.

Seeing as how Solarix stated the Xantrex inverter is 4 yrs. old, if Xantrex makes primarily bimodal inverters "now", I kind of wonder if that affects your thinking about batteries being involved.

[ButchDeal]

I think we (or I at least) need some direction and info from Solarix as to orientation(s). If an array was split, I'd tend toward thinking (and perhaps incorrectly so) that the former single array was at one orientation or similar orientations, particularly with the as stated similar output. I see no compelling reason from what I read of Solarix' posts to think that one half of the original array is shaded more than the other half as you seem to be writing or implying.

I also see that I need some clarification from Solarix as to any storage capabilities in either current system and how such capabilities would affect array production.

Seeing as how Solarix stated the Xantrex inverter is 4 yrs. old, if Xantrex makes primarily bimodal inverters "now", I kind of wonder if that affects your thinking about batteries being involved.

Well he said roof mount, tilted with partial shade from rows. So the first row would not be shaded by any other row.

I agree I (very possibly incorrectly) assumed the Xantrex (no Schneider) was bimodal so yes some more details would help.
Xantrex has made bimodal and off grid since formed.

[J.P.M.]

Well he said roof mount, tilted with partial shade from rows. So the first row would not be shaded by any other row.

I agree I (very possibly incorrectly) assumed the Xantrex (no Schneider) was bimodal so yes some more details would help.
Xantrex has made bimodal and off grid since formed.

I propose we wait for Solarix to provide some resolution and stop sniping at one another.

Solarix ?

[solarix]

Sorry, been busy. The Xantrex is the circa 2010 GT type. No batteries. The difference in production is small enough to be a statistical dead heat. But my conclusion is that all the SolarEdge promises about "up to 2% gain because of panel mismatch, up to 2% gain because of cloud lensing, up to 2% gain because of ...." is a bunch of "up to" B.S.

[ButchDeal]

Sorry, been busy. The Xantrex is the circa 2010 GT type. No batteries. The difference in production is small enough to be a statistical dead heat. But my conclusion is that all the SolarEdge promises about "up to 2% gain because of panel mismatch, up to 2% gain because of cloud lensing, up to 2% gain because of ...." is a bunch of "up to" B.S.

which inverter is the first row connected to? (assuming first row is unshadowed from other rows)

[solarix]

Actually, the best, front row is connected to the SolarEdge... Collins.jpg
24 - 230w Trina panels, 6 rows of 4, 12 on each inverter. Panels were purchased together all from same pallet.

[littleharbor]

If you have a problem with a panel, even on the Xantrex GT, you should be able to spot it, with such close readings.