6Kw going in soon in Aliso Viejo

[OftheSeven]

That is an awesome output. Base on Enphase white paper that undersize inverter yield higher overall production. I understand you have 24 M215 microinverters pairing with 270W panel. I was wondering what would be your max instantaneous output? 230W AC X 24?

Thanks Bob! Your output does look great. My main concern was whether a higher elevation west facing roof location was better/worse than a lower elevation south facing roof with late afternoon shading?

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We may be able to fit more than the two on the East roof facing South, or I could just leave the ones on the higher West facing roof. My wife would prefer more in the back yard for aesthetic reasons.

[silversaver]

Thanks Bob! Your output does look great. My main concern was whether a higher elevation west facing roof location was better/worse than a lower elevation south facing roof with late afternoon shading?

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We may be able to fit more than the two on the East roof facing South, or I could just leave the ones on the higher West facing roof. My wife would prefer more in the back yard for aesthetic reasons.

Depends on when the shading starts. Any shadow before 9am or later than 4pm and 6pm (Summer) you don't really need to worry about it.

I have chimney shadow after 6pm in Summer, it aint too bad.

PS. I'll put the panels on the back yard roofs instead of facing the street. I don't like panels on front of the house. You can add few more panels to make up the difference if needed since you have the space on the roof.

[Alisobob]

I was wondering what would be your max instantaneous output? 230W AC X 24?

My "Peak Output". so far.. if thats close to the same thing your asking.. is 5.25 KW AC ( off a 6.48 KW DC nameplate system)

Your equation would equal 5.52 KW AC output.

Maybe in a few more months, as the sun gets higher...

[silversaver]

My "Peak Output". so far.. if thats close to the same thing your asking.. is 5.25 KW AC ( off a 6.48 KW DC nameplate system)

Your equation would equal 5.52 KW AC output.

Maybe in a few more months, as the sun gets higher...

I think you will see that next month!!

[Alisobob]

Any shadow before 9am or later than 4pm and 6pm (Summer) you don't really need to worry about it.

I'll agree with that, and add that some of my neighbors have some East facing panels that seem kinds useless.

Even without "shading" from a chimney or tree... they seldom get full sun due to cloud cover or fog, that burns off after 10am of so... right about the time my South facing panels start to crank out the juice.

I'm no expert on this, but stick as many as you can facing South, then add as many facing West as you need to hit your numbers.

East facing seems like a real waste, as least in my area.

[bcroe]

I'll agree with that, and add that some of my neighbors have some East facing panels that seem kinds useless.

Even without "shading" from a chimney or tree... they seldom get full sun due to cloud cover or fog, that burns off after 10am of so... right about the time my South facing panels start to crank out the juice.

I'm no expert on this, but stick as many as you can facing South, then add as many facing West as you need to hit your numbers.

East facing seems like a real waste, as least in my area.

This will vary. Here we often get good morning sun, followed by clouding in the afternoon.
East facing panels put me at 100% by 9am, for half the year if the sun is out. Bruce Roe

[J.P.M.]

I'll agree with that, and add that some of my neighbors have some East facing panels that seem kinds useless.

Even without "shading" from a chimney or tree... they seldom get full sun due to cloud cover or fog, that burns off after 10am of so... right about the time my South facing panels start to crank out the juice.

I'm no expert on this, but stick as many as you can facing South, then add as many facing West as you need to hit your numbers.

East facing seems like a real waste, as least in my area.

Where you are, east facing is not a real waste, but surely not as productive as mostly south facing. Your sort of westerly facing ( if I recall correctly) is better than east, but not as good as probably something like 10-20 deg. west of south, or mostly south facing.

[OftheSeven]

Depends on when the shading starts. Any shadow before 9am or later than 4pm and 6pm (Summer) you don't really need to worry about it.

I have chimney shadow after 6pm in Summer, it aint too bad.

PS. I'll put the panels on the back yard roofs instead of facing the street. I don't like panels on front of the house. You can add few more panels to make up the difference if needed since you have the space on the roof.

Thanks for the info. I checked today and the shading (this time of year) didn't occur until 4PM on the back south roof, so I think I'll go that route.

Sorry, Bob. Didn't mean to hijack your thread.

[Alisobob]

No worries.... Info is info... might help someone in the same boat. as you.

[Alisobob]

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Feb was a good month. At one stretch, I had 19 days in a row over 30 KWH's...

856 KWH's generated vs a projected 625...

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37 KWH's off 6.4 KV nameplate... not too bad for Feb.

Onwards into March, and hopefully sunny days...

[bcroe]

Here in cloud land, the Feb output per day was 2.3 times the Jan output per day. Bruce Roe

[Alisobob]

Sun has to come out sooner of later... hang in there Bruce.

[silversaver]

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Feb was a good month. At one stretch, I had 19 days in a row over 30 KWH's...

856 KWH's generated vs a projected 625...

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37 KWH's off 6.4 KV nameplate... not too bad for Feb.

Onwards into March, and hopefully sunny days...

try SAM, better tool. you can watch the video there

https://sam.nrel.gov/content/downloads

[J.P.M.]

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Feb was a good month. At one stretch, I had 19 days in a row over 30 KWH's...

856 KWH's generated vs a projected 625...

[ATTACH=CONFIG]5945[/ATTACH]

37 KWH's off 6.4 KV nameplate... not too bad for Feb.

Onwards into March, and hopefully sunny days...

PVWatts and other tools are estimators of long term performance. What you are actually comparing is estimated performance based on some prior year's Feb. weather to your actual performance based on the weather for the Feb. just ended, which may or may bear any resemblance to the weather for the month PVWatts used for it's long term estimate. To say you beat PVWatts or any estimating tool is about equivalent to comparing the weather for some Feb. in the past to the Feb. just ended. It says nothing about the accuracy of PVWatts or the possible performance of your system. Next Feb. you could be a goat. Who's off then ? Would that mean your system is malfunctioning ?

Suit yourself, but I'd respectfully suggest a reading of the PVWatts help/info screens and a reading of the NREL TMY information would clear u a lot of confusion.

Take what you want of the above. Scrap the rest.

[Alisobob]

To say you beat PVWattsor any estimating tool is about equivalent to comparing the weather for some Feb. in the past to the Feb. just ended. It says nothing about the accuracy of PVWatts or the possible performance of your system. Next Feb. you could be a goat. Who's off then ? Would that mean your system is malfunctioning ?

I was careful not to use the "beat" word in my post. I understand that numbers the PVWatts site generates are purely hypothetical, and may vary widely, month to month and year to year.

Thats why I posted this... While Feb 2015 appears to be abnormally good, what comes in March .... remains to be seen.