Sales Engineer from Boulder, CO

[Sunking]

The 130 numbers are off of Walt's array as what it is producing right now using some 230 watt panels among other wattage rated panels in Colorado. Ironically all the panels regardless of rated wattage are very close in output,

Probable not as close as you think. This is why you should never mix panels.

[trbizwiz]

Probable not as close as you think. This is why you should never mix panels.

Even with their individual inverters?
Do you think if these were arrays of 10 panels each, that one array would have significantly different numbers than another other than the factor of 5 (currently 2 panels changing to 10 panels makes the factor of 5)
Or , would you think this would illustrate the weakness of the enphase single inverter for single panel design as opposed to mounting panels in a string and connecting to a central inverter? I have been under the impression that enphases design was more efficient than the other, maybe this disproves that??

[Sunking]

Maybe I am late in the game and have not read all the post. If you use an enphase inverter for each panel, then mixing panels should not be a problem. It is the mixing of panels in strings and parallels is where the problem occurs.

OK with that said if you have a 230 watt panel, and the most you have ever seen it produce is 130 watts something is wrong. 230 watts is likely the STC rating which is not real. However the PTC or real world power should be around 80 to 90% of the STC rating. So if you have a 230 watt panel. I would expect to see 185 to 200 watts at solar noon on a bright sunny day.

[trbizwiz]

Maybe I am late in the game and have not read all the post. If you use an enphase inverter for each panel, then mixing panels should not be a problem. It is the mixing of panels in strings and parallels is where the problem occurs.

OK with that said if you have a 230 watt panel, and the most you have ever seen it produce is 130 watts something is wrong. 230 watts is likely the STC rating which is not real. However the PTC or real world power should be around 80 to 90% of the STC rating. So if you have a 230 watt panel. I would expect to see 185 to 200 watts at solar noon on a bright sunny day.

The 130 watt number comes from walts post above. If you click on the link it takes you to the enphase website. The 10 panels ranged from 127 to 131 at around noon mountain time.

@Walt are these in a shady area? Are they dirty?, Do they not point true south, or is the angle wrong? Why would you suspect the output is lower than the projected 180 watts?

[Mike90250]

.....

@Walt are these in a shady area? Are they dirty?, Do they not point true south, or is the angle wrong? Why would you suspect the output is lower than the projected 180 watts?

They are roof mounted I suspect. And you get the sun angle that the roof is at.
For fixed arrays, there will be about a 15 minute "sweet spot" daily, as the sun is most perpendecular to the array. You can't change the roof angle/pitch, or the house orientation, so the panel's sweet spot may be at 2:30 pm or 11:45am

My west faceing GT array peaked about 3pm. I have max power for about 6 days each June, then it degrades.

[Walt_Solartown]

Hey there - just wanted to let you know my array is CSI 230s, and I do see outputs of 199 watts from the Enphase M190 micro-inverters. It's been cloudy and hot this week along our area of the Front Range. I am wondering if my panels are a bit dusty but I think the lessened output is a result of the clouds and heat. Perhaps in September the numbers will inch back up.

[trbizwiz]

Hey there - just wanted to let you know my array is CSI 230s, and I do see outputs of 199 watts from the Enphase M190 micro-inverters. It's been cloudy and hot this week along our area of the Front Range. I am wondering if my panels are a bit dusty but I think the lessened output is a result of the clouds and heat. Perhaps in September the numbers will inch back up.

Csi is Canadian solar right?

[crxvfr]

Enphase ....

Every time I turn around I hear of a new gadget. Can you use these microinverters on more than one panel so long as you don't go past voltage or amperage limits? Say you have an array of 42 panels that are in columns of 3. 14 columns. Can you have a microinverter for each column? If you have MPPT microinverters, can you use them with a charge controller? ...or are they only for net metering.

EDIT ADD: Nevermind, found out via google.