Solar panel cooling fan?

[JJJJ]

So there is a lot of discussion on panel temperature and winter being a great time for power production due to panel cooling.

Was considering an idea which would not work well on the roof but might be a consideration for a ground mount situation. There is plenty written about solar panel driven cooling fans in attics. Was sipping the second cup of coffee and was pondering an idea. What if one were to string a separate 100w panel to the side and attach it to one or two cooling fans which were positioned underneath a ground array? As the intensity of the sun increased the fans would pull air from the ground and allow air flow at the undersides of the solar panels.

Has anyone tried this?

 

[SeaGal]

What if one were to string a separate 100w panel to the side and attach it to one or two cooling fans which were positioned underneath a ground array?

I'm sure someone with a degree in thermodynamics will come along, but my gut feeling is a cooling fan underneath a ground array will do ***-all to the surface temperature of a 2m^2 of black panel in direct sunlight. (Sorry... it's being so cheerful that keeps me going )

 

[Cmiller17363]

What about a solar powered water pump flushing the surface of the panels on the top? Put gutters on the array, collect rainwater, add plumbing to the top of the array to flush the panels with water, then recollect the water in the gutters and do it all over again. Add a heat exchanger if the water temps rise too much. Could be a fun side project, I would love to see the performance results.

 

[ScrotusGobbleBottom]

What about a solar powered water pump flushing the surface of the panels on the top? Put gutters on the array, collect rainwater, add plumbing to the top of the array to flush the panels with water, then recollect the water in the gutters and do it all over again. Add a heat exchanger if the water temps rise too much. Could be a fun side project, I would love to see the performance results.

You would have to cool the water constantly. My panels love 40 degrees F.

 

[SeaGal]

I would love to see the performance results.

I thought the degradation is specified, typically -0.25% per degree C, so only about 5% gained by reducing surface temperature by 20C. Cheaper and simpler, IMHO, to just buy another panel for the summer

 

[JJJJ]

Just watched an interesting video on vertical bifacial panels. It was proposed that the vertical positioning allowed slightly better airflow and it was the cooler operating temperatures which helped efficiency. They quoted a Dutch study. https://www.pv-magazine.com/2023/11...-higher-energy-yields-in-vertical-pv-systems/

 

[Cmiller17363]

I thought the degradation is specified, typically -0.25% per degree C, so only about 5% gained by reducing surface temperature by 20C. Cheaper and simpler, IMHO, to just buy another panel for the summer

Cheaper and simpler is the goal? I've been doing it all wrong!

 

[timselectric]

The problem is efficiency.
It's hard to add cooling that doesn't take more power than it increases.

 

[hwy17]

Water cooling systems will probably leave deposits, so better off installing an A/C window unit blowing cool air over the panels.

 

[AmpD]

I saw a YouTube experiment using water to cool a panel

 

[LakeHouse]

All of these potential cooling options (except one) have the same problem: You would need to get more extra power than it costs you to run the fan/water pump/ whatever. And that’s not very likely. Are you going to get 10% more power out of a 1000W array with 100W of fan cooling? Not likely. So adding 100W of panels makes more power.
The exception? Vertical panels, or tilting closer to vertical. Convective cooling is free and the difference in convective cooling between a vertical surface and a horizontal surface is quite large because the heat creates vertical airflow, sort of making artificial wind over the panels. The downside might be that less sunlight hits your panels because they aren’t facing the sun. It’s a trade-off that may or may not be worthwhile.