Tip up solar panels, real world numbers

[66788]

Today was a good day to conduct a little experiment. The weather here was about 75 degrees and cloudy. I had the ARB compressor fridge running with the solar panel flat on the roof of the van, and the panel was charging at 3.7 amps. I observed this go from 3.6 to 4 amps depending on the sunlight penetrating the cloud cover.

I then tipped up the panel on the tip up mount I designed and the amps went from 3.6 to 5.6 amps. About a 50% increase in usable power just by tipping the panel.

Those of us running less than minimal watts of solar panels would be well advised to devise a tip up system to ensure all of the power possible is being generated by the panels, or have enough extra solar so that you don't have to do that.

 

[akrvbob]

Thanks so much for doing that. I'm impressed it was that much and it kind of changes my mind about the value of tilting!
Bob

 

[66788]

There are a few variable factors in testing a panel for output and let me start out by saying I am no expert. I have been using various solar panels for about 8 years now and I've never seen one produce the stated output, even when new. A new panel will come closer than a used one, but as solar panels age the output diminishes. I think by as much as 20%. They usually do hold at 80% for quite a long time, as much as 30 years.

My Kyocera KC120 is a 120 watt panel and should produce up to 7.9 amps output. I've seen 6.5 but that's all.

Maybe someone who actually knows about this will jump in and educate us all.

 

[LeeRevell]

Can't wait to see your numbers in a summer Southwest setting!

 

[Spaceman Spiff]

Panels are rated at a standardized test condition we are unlikely to see in use: 1000 Watt per square meter, air mass = 1.5, wind = 1 meter/second 10 meters above the ground, ASTM G173-03 standard spectrum, with solar cell temperature (NOT ambient air temp) of 25°C., with new clean glass over cells.

You might see something close with cloud edge effects, but with all the dirt in the air and especially in winter, with the extra atmosphere for the light to go through, getting 1000 watts to cool cells ain't going to happen.

-- Spiff

 

[Optimistic Paranoid]

I think the published output under "Standard Test conditions" merely gives you a way to compare different panels from different manufacturers fairly.

The standard test conditions are actually artificially ideal test conditions, impossible to achieve in the real world, and thus no one should actually expect to see their panels produce that much power.

Regards
John

 

[Zil]

Test conditions are standard only to each individual manufacturer. Comparing different manufacture's data is not valid.

 

[1977dodge]

Today was a good day to conduct a little experiment. The weather here was about 75 degrees and cloudy. I had the ARB compressor fridge running with the solar panel flat on the roof of the van, and the panel was charging at 3.7 amps. I observed this go from 3.6 to 4 amps depending on the sunlight penetrating the cloud cover.

I then tipped up the panel on the tip up mount I designed and the amps went from 3.6 to 5.6 amps. About a 50% increase in usable power just by tipping the panel.

Those of us running less than minimal watts of solar panels would be well advised to devise a tip up system to ensure all of the power possible is being generated by the panels, or have enough extra solar so that you don't have to do that.

Hi
looks good for the increase of course its a small chore to get up and down on the van but probably worthwhile for the gain
do you have any c lose up pix of the mount

 

[66788]

I can adjust the tilt function of the mounts while standing at the open back doors. No ladder needed.

Mount detail in this post:

https://vanlivingforum.com/showthread.php?tid=8918&page=2