Get Extra Output from Your Solar Panels

Back in March & April when the skies were partly cloudy most days, I noticed my 10 PV200 were putting out 2.2kw for 4 hours, but when skies were clear they only peaked at 1.5kw. A forum user educated me on the Lens Effect being responsible, where clouds redirected more light towards the panels. It really intrigued me & I decided to see if I could reproduce it. I laid out some large white foam sheets next to my ground mounted panels to see how the output would be affected.

My six 200w panel’s output jumped anywhere from 100 to 400w more than not having the white sheets.

The 380w output was without any foam sheets & the others are from different configurations of the foam sheets. I was impressed at the increase. I also apologize for selecting some screenshots that were taken hours later. My selection screen cut off the tops of my images & I couldn’t tell what time they were taken until after I attached them. The actual one I was trying to get was one that I took 1 minute after the 390w reading which was 785w. Next I’m ordering a reflective mylar sheet with a diamond aluminum coating, which I’m going to glue down onto a 1/4 in. sheet of plywood & see how much more output I get. In a way this is kinda pointless. I’m going to make 2 separate solar tracking mounts before summer is over, so I won’t need any reflective sheets. I just did this project to satisfy my curiosity.


Being able to “aim” your array at the sun will always give you the biggest boost. People have come up with various designs that you can find on youtube. One guy had real time computerized sun tracking, but it could only hold a few large panels.
I have 15 100-watt panels that I can “see-saw” east/west. The night before, I tilt the array eastward and start catching a few hundred watts around 7am.
I’ve seen a 200 watt increase tilting the array from it’s Noon position to the sun’s 3pm position. From there I leave it tilted west the rest of the day. Unfortunately there’s a block wall that will cast a shadow by 6-7pm, but a 100 watts or so still trickle in.

I could use an antenna rotor to do the tilting, but the cheap ones on Amazon don’t last because the gears are plastic. I’ve been looking at small but heavily geared 12V reversible motors that might work. Mount the motor on the ground, wrap a cord around the motor’s pully, and the ends of the cord to each end of the array, forming a “V.” As it pulls down on one side the other side goes up.

The white sheets are a very good idea !
If combined with bifacial panels which have the ability to capture sunlight from both sides, you can have a lot more energy compared to traditional solar panels.

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New tier-1 panels are usually much more resistant to heat, but all panels experience a drop in power output when the sun’s too strong;

The more sunlight they receive, the more power they can generate. Counterintuitively, if the panels become too hot, they will actually produce less electricity. Overheating reduces solar panel efficiency, impacting the percentage of sunlight the panel can transform into power

One can expect a drop of about 0.5% per °C in average panels.

I noticed that too when I used a hose to clean bird droppings. I then sprayed all my other panels and got a short term boost. Of course, here in Vegas we’re having a water shortage so I gave up any thoughts of having a “misting” system for the panels.

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If you’ve reached the max inputs for the Bluetti’s PV inputs, you can plug more panels directly into the B300s batteries using the provided cables. Just stay within the input limits of 60 volts, 500 watts, 10 amps.
Each of my 4 batteries has it’s own panels in addition to the main arrays.
The added power won’t show up on the APP or touch screen, but a clamp ammeter will show amps are being pulled. And of course a voltmeter will show voltage from the panels (and to make sure it’s below 60 volts.


So you mean the battery’s MPPT isn’t limited to 200W like the spec says?

Sorry, I was referring to the “S” version, B300s. I didn’t notice he had the AC300 instead of the AC500.

So yeah, 200 Watts, but it’s still 60volts/10a input limit. You could add a pair of those Renogy 100W panels on Amazon for $149. Wired in Series would give you 48.6V at 5.21A. As always, you never get the rated wattage from a solar panel, so you might get 180 watts total.

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Well I’ll try a Trina or Longi 405, I have a few spares and will use a multimeter in series to see how much amps are flowing. I suppose if there’s a limit to 200W in B300 then it must come from the MPPT and/or charge controller that’s likely to be a 60/8 … and that’s 8amps of output at 24Volts if the internals are similar to Victron SmartSolar and the likes.

I’ll post when I’ve done the test!

BTW. do you get good results with Renogy? I’ve had poor results with Jingyang as described in my post below. I’m not very confident buying more portable panels. I’d rather leave a few roof panels on that offgrid piece of land. Portable panels are like 4 to 8 times as expensive as rooftop panels per Watt.

I only buy regular panels, not flexible. Those are obviously for camping.

I have 15 of those 100 watt Renogy panels, (3 strings of 5 panels, in parallel to keep the Voc below 150Volts), as they’re the best bang for the buck. I started with 10 and saw the need to buy more as I bought more B300s batteries. I have other panels, some off Craigslist.

So I figured out how to mount all 15 to one “aim” able array, that seesaws east west to get the most sun. The 1500 theoretical watts gives me on average 1300 watts. I did see a spike of 1380 watts during a cloud lensing effect.
My current system recharges 4 B300s batteries by around 3-4pm everyday, while maintaining a load of other things.
The excessive summer heat in Vegas has been cutting into my solar power, dropping my array down into the 1100-1200 Watt range. We’re talking some 118 degrees during the day, with some nights almost at 100. I’m kind of used to it, but there were times when the air itself at night smelled burnt. On the other hand, we have a whole lot of blue sky cloudless days to collect solar power for air conditioners :sunglasses: And when the rest of the country is in negative freezing temps, we’re usually in the 70s.

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Be mindful that most voltmeters have a 10 Amp limit, including my moderately expensive Fluke meter, but it is fuse protected.
Most common individual panels will be below 10 Amps, but in parallel the Amps will add up.

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