SolarEdge Optimizer Difference in Capped Output

[SoCalGal2]

Installing 34 MONO panels LG model # LG260S1C-G2 with SolarEdge Optimizers. One vendor (A) has in stock the Op-250-LV optimizers and another vendor (B) insists I should be using the OP-300-LV optimizers because the 300's are for panels above 250 watts (mine are 260) and he says there is potential the OP-250-LV could cap off at 250 watts as they are not capable above 250 watts. The vendor who wants to use the OP-250s says that panels "rarely" perform to peak, but he primarily installs lesser panels - not mono.

I live in high desert at 2250 feet above sea level and get peak performance up here. I don't want to sacrifice one iota of production.

The problem? I need to know what potential production I could be losing if I have 260 watt quality mono panels and use optimizers that cap off at 250 watts. Is there anyone technical out there than can quantify this for me in some way?
Thanks for your time - truly appreciated.

[carultch]

Installing 34 MONO panels LG model # LG260S1C-G2 with SolarEdge Optimizers. One vendor (A) has in stock the Op-250-LV optimizers and another vendor (B) insists I should be using the OP-300-LV optimizers because the 300's are for panels above 250 watts (mine are 260) and he says there is potential the OP-250-LV could cap off at 250 watts as they are not capable above 250 watts. The vendor who wants to use the OP-250s says that panels "rarely" perform to peak, but he primarily installs lesser panels - not mono.

I live in high desert at 2250 feet above sea level and get peak performance up here. I don't want to sacrifice one iota of production.

The problem? I need to know what potential production I could be losing if I have 260 watt quality mono panels and use optimizers that cap off at 250 watts. Is there anyone technical out there than can quantify this for me in some way?
Thanks for your time - truly appreciated.

I recommend running a PV Watts calculation, at a well-representative weather data site, at your tilt and azimuth, with all derates set as close to unity as the program permits.

The justification for this, is that we are analyzing at the module level, so there is no applicable mismatch or inverter, or wiring loss.

Now save the hourly data to Excel, and count how many hours exceed the total kW worth of optimizers you have installed, taking note of the wattage difference. Compare this to the annual sum, and that will be proportionally how much you can expect to loose.

[Ian S]

Installing 34 MONO panels LG model # LG260S1C-G2 with SolarEdge Optimizers. One vendor (A) has in stock the Op-250-LV optimizers and another vendor (B) insists I should be using the OP-300-LV optimizers because the 300's are for panels above 250 watts (mine are 260) and he says there is potential the OP-250-LV could cap off at 250 watts as they are not capable above 250 watts. The vendor who wants to use the OP-250s says that panels "rarely" perform to peak, but he primarily installs lesser panels - not mono.

I live in high desert at 2250 feet above sea level and get peak performance up here. I don't want to sacrifice one iota of production.

The problem? I need to know what potential production I could be losing if I have 260 watt quality mono panels and use optimizers that cap off at 250 watts. Is there anyone technical out there than can quantify this for me in some way?
Thanks for your time - truly appreciated.

Vendor A is correct in stating that panels rarely will output the nameplate power but let's say there are days when they do. Assuming your power curve during the day is shaped similarly to mine, then for every day your peak panel power just barely reaches the full 260 watts, I estimate that the 250 watt optimizer limit would cap off for a period of about 2.5 hours roughly around the noon hour. You could integrate the power curve over time to get the actual amount of energy lost due to the cap but the lost part of the curve we are interested in is roughly triangular with a base of 2.5 hr and a height of 10 watts. Area of a triangle is 1/2 x base x height, so the energy lost per panel is 0.5 x 2.5 x 10 watt-hr = 12.5 watt-hr or 0.0125 kWh. Multiply that by the number of panels - 34 - and you wind up with about 0.425 kWh. Even in the high desert, conditions where you'll see the nameplate power will actually be rare but for sake of argument, let's say it happens once a week. Total lost kWh annually would then be 52 x .425 = ~22 kWh. IMHO that's negligible.

[HX_Guy]

Installing 34 MONO panels LG model # LG260S1C-G2 with SolarEdge Optimizers. One vendor (A) has in stock the Op-250-LV optimizers and another vendor (B) insists I should be using the OP-300-LV optimizers because the 300's are for panels above 250 watts (mine are 260) and he says there is potential the OP-250-LV could cap off at 250 watts as they are not capable above 250 watts. The vendor who wants to use the OP-250s says that panels "rarely" perform to peak, but he primarily installs lesser panels - not mono.

I live in high desert at 2250 feet above sea level and get peak performance up here. I don't want to sacrifice one iota of production.

The problem? I need to know what potential production I could be losing if I have 260 watt quality mono panels and use optimizers that cap off at 250 watts. Is there anyone technical out there than can quantify this for me in some way?
Thanks for your time - truly appreciated.

The "correct" optimizer would be the OP-300, that is what SolarEdge would recommend. I recently talked to them and asked if I could use the P300 with a 305W panel and they said I would need the P350 since the P300 is for 300W and lower.

Having said that, I think you'll be fine using the OP-250, I really doubt you've ever see the panel product that much, usually you'll see 85%-90% of rated power, so 221W - 234W would be realistic.

One other thing though, the OP line has been discontinued and replaced by the P Series, with the P300 being the smallest available module. I don't know of any performance differences, but the P Series has a simpler install with integrated grounding and could have better, upgraded internals.

[bcroe]

The "correct" optimizer would be the OP-300, that is what SolarEdge would recommend. I recently talked to them and asked if I could use the P300 with a 305W panel and they said I would need the P350 since the P300 is for 300W and lower.

I have a friend at 11,000 feet (Alma, CO). His array gets intense sun most days. In winter
it's cold, the array is tipped up, and the snow reflects more sun to the panels. He eventually
decided to up the inverter size 10%, to cover the power. However, most will not have
conditions this good. Bruce Roe