[RE-wrenches] overfeed 7kW gridtie inverter or drop a mod per string?

[Jim MacDonald]

For a straight grid-tie system@ 10 degree tilt, 180 azimuth, zero/little shade, NYC avg 4.29 kWh/m²/day.

Feed an SMA7000 with (3) strings of 11 Suntech STP275's [9.075 kWdc]
Or
Do strings of 10, so itd be 8.250 kWdc into the 7 kWac inverter.

Strings of 11= 491.7 Voc; 386 Vmp
Strings of 10= 447 Voc; 351 Vmp

The tradeoff would be power clipping at/around noon in the sunny months in the 9.075 kW scenario;
Inverter sleeping late every morning and retiring early in the evenings in the lowered voltage scenario.

Trying to figure out which would yield more kWh at the end of the year.

Any ideas appreciated,
thanks




Jim MacDonald
Solar Energy Systems, LLC
Brooklyn, NY 11222
www.solarEsystems.com<http://www.solaresystems.com/>

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