Sp120 panels under powered

I’ve had my panels for over a year. They work pretty decently. I rarely see over 175 watts with two in series. Ive seen 200 watts for a biref second but not consistently. I have used the panels in temps ranging from 55 to 95 degrees and the results are about the same. Just watched a youtube video and a guys sp120 was putting out over 110watts in the winter. Also watch a video of bouge rv and renogy rigid panels producing 95%+ of rated wattage. I’m wondering why my bluetti panels don’t ever produce their rated wattage. Any suggestions?

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I’ve seen 110 watts out of my Bluetti PV120’s for a few minutes when they were just out of the garage and cool but once warmed up they drop down to about 90-95w (75%). My Bluetti SP200’s and Renogy 200’s are about the same at 70-80% when hot.

But without a calibrated in line watt meter who knows what the real numbers are.

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What’s your elevation?
I’ve tested these from 700feet to 7000k feet above sea level at different times of the year. Pretty consistent accross the board and higher elevation was definitely better by a little.

400 feet and near the salt water so we can have some moisture in the air even on a perfectly clear day.

Moisture will play a big part in filtering out the solar energy reaching your panels. I live several miles from the beach in SW floriday and even on a clear day I can only get around 60 % or so of the rated capacity in humidity.


Exactly, my best solar results are when the breeze is off shore. I’m about a mile from the water.

Almost no panel would produce rated power. Panels are rated at standard test condition which is 25c junction temp at 1000w/sq meter, clear transparent sky. In those condition, junction temp would rise quickly beyond 25c and power will decrease. It is pretty much tropical sun in subarctic temp. Not happening.

I would be happy to get 85% rated power under real conditions. I once hit 90% on a cold April day, but that was exceptional.

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When looking at panels (any panel) i just calculate 80% (most probable) of the rated declared wattage when working out my array stats.