It's Pollen Season - What is the Cut in Your Solar Production?

MrM1

I noticed yesterday on a perfectly clear day ... and the longest amount of daylight we have had all year,  that my solar production was not what it was a few weeks ago.  Hmmmm ??  What could it be?   I debated with myself,  perhaps it was warmer temps,  or just that my loads were not as demanding.  So I cranked everything up and all that did was start to draw off the battery.  The most I could get from my array was 1900 Watts give or take.  Yet a few weeks ago,  I saw Watt numbers sore to 2303 Watts from this little 2565 Watt array.  

What could it be?   Then a few nights ago on what seemed to have been a clear night,  we got a freak quick shower.   The next morning,  the car I had detailed to a mirror like finish was all spotted ... AND covered in pollen that had stuck to the rain thru the night.  And by the after noon, and another day of lack luster production in clear conditions, I wondered how much pollen might have collected on the array nearly 2 stories up on the roof.  A quick gander from the neighbors carport gave me the answer,  they looked like a sea of yellow.  

So I armed myself with a hose and sprayer, soft brush on a pole and ladder.  Up to the roof I go.  Pollen, literally stuck on the panels,  so much so that spraying alone would not break it loose.  The brush came in handy.  A light scrubbing and the panels were clean again.  Tomorrow is another perfectly clear day.  So I expect to see higher numbers again.  To the best of my guess,  this Pollen Haze accounted for about a 10-15% drop in production.   The bad news ... the season is not over yet.  Good news,  it only took 15 minutes to clean them including setting up and putting away the ladder. 

Yes it is that time of year in Sunny North Florida. Pine,  Oak ... pick your poison.

mike95490

Just be sure to do the scrubbing when the panels are cool, pre dawn.  cold water on hot glass, wont hurt the first few dozen times.....

MrM1

mike95490 said:

Just be sure to do the scrubbing when the panels are cool, pre dawn.  cold water on hot glass, wont hurt the first few dozen times.....

ha ha ha ha ... yes true that.  Did it at dusk on a 65* hi day.  It was about 55* when cleaning.  But good point. 

Estragon

Pollen season usually runs with a fair bit of rain at the cabin, so I've never had to clean panels just on account of that. I hope they aren't all that prone to cracking if hit with cold water when hot though. It's not at all unusual for the panels to be in full June sun when a squall rolls through hitting them with cold rain and sometimes hail.

mcgivor

The production output is dependent on various factors including panel temperature, battery voltage, winds cooling effect and of course dirt or pollen buildup. As an experiment I recorded the output of each of 2 strings similltaniously, then washed one string leaving the other dirty, the output which were almost identical before were significantly different, strangely the dirty ones were producing more than the clean ones, the dirt was a thin film of black dust due to lcoal bush fires. My findings in this case were opposite when there was light brown soil dust, once washed the production rose, so it would appear different dirt affects output differently, the possible reason my be how much light reflected. Pollen being a lighter color may reflect more, it will be interesting to see your results. The side by side comparison of identical strings at the same plane was the best method I could think of, because the variables from one day to the next could skewer results.

mike95490

Freshly iced panels, slushy snow sliding off, and cold temps, have my production way up, even in semi-cloudy skys

Raj174

It's heavily coating panels and cars here in north Florida. I'm having to spray them off 3 times a week. Average power production is down 7%.  

Rick

MrM1

I saw power production up over 2100 Watts consistent today with clean panels.  Day before with almost the exact same conditions and battery DOD I could only get the panels to consistently run at 1850 Watts.    AND today was the largest production day of my little arrays short life ... 10.7 kWh.