Bi-facial Panels

[Charles Godwin]

I installed 4 LG NeON 2 LG380N2T-A5 panels this summer. I selected them because of their density. I have a roof mounted system and wanted about 1,500 watts. I did not have the width for six shorter, 60 cell, units. I did not buy them for their supposed extra, bi-facial output, but wondered if I would see anything from the feature.

I have software to log inputs and outputs to/from my charge controller so I can compare charging performance day by day. After just 3 weeks operating in the Laurentians north-east of Ottawa I notice that early morning and late afternoon performance is interesting. If it's cloudy or even raining I get much more output than if its a clear sunny day. I suspect this is because of the ability of the bi-facial panels to pick up cloud dispersed solar radiation from both faces.

Would I buy these expecting the extra bi-facial output? Probably not, I'd spend the money on more regular panels. But my case was different because of space issues.

[Joe Blake]

Hi Charles,

For what it's worth, I don't have bi-facial panels and I still experience the increased generation effect of cloudy skies. Several theories are put around to explain it, one of which is the "Cloud Edge Effect" which sounds like what you are saying. Another theory is that the clouds can create a "bigger" area of light. Anyway, it's a very real effect (perhaps Google "Cloud Edge Effect") that, at least in my experience, doesn't need bi-facial panels to harness it.

Joe

[Charles Godwin]

Joe

I agree, it's probably the cloud effect. I'll keep watching my charts and see if I can spot any useful data to support bi-facial bonus power.

[Rob Beckers]

I have 118kW of panels on the roof here, and notice this too (they are regular single-face panels). One reason is temperature: On a nice sunny (cloudless) day in summer the panels won't quite produce 100kW AC because they simply get too hot. With ambient temp at 25 - 30C, and the sun on the panels, they easily reach 60C, which costs about 20% in power output.

One a cloudy day, even if it is 25 - 30C outside, the panels stay MUCH cooler. The moment the sun peaks out behind a cloud they are still relatively cold, and will instantly produce 101 kW AC (the max of my inverters).

Now, overall a sunny day will produce more energy of course, even if the panels never get near rated output.

-RoB-

[Charles Godwin]

Wow, I assume that's the array on top of your store. A few more panels than mine;)

Maybe you should develop a water or air cooling system. Joking

I installed these panels at the beginning of August but since they are more than adequate for charging my batteries I am never stressing the panels to produce peak output. i'm normally into absorption mode late morning before I get peak sunshine. good for my batteries but not good for my research. I think i'll learn more more next summer since in July my occupant count jumps from just 2 to a more load draining 10 when the whole family visits. I'm paying attention to the early and late day events.

[Drake Ramore]

How you think can I install same bi-facial panels in townhouse..? I just installed a new A/C and furnace, so I am not looking to change anything in my current town house, but, given the need to find alternative sources of energy I want do something what economed my budget.

[Charles Godwin]

I'm not convinced that the extra cost of the bi-facial units is justified. I bought them as the panels were larger capacity for the same square footage and I had a space constraint. If I had more space I'd just use regular, much cheaper, panes.

[Drake Ramore]

I bought a single panel installation with a 245W module and a 260W micro-inverter, installed on my balcony and directly hooked up to an outdoor power outlet. It includes a monitoring hub and software that didn't work initially. Learned a lot from this review [Admin: Gratuitous back-link removed.]

[Drake Ramore]

I bought a single panel installation with a 245W module and a 260W micro-inverter, installed on my balcony and directly hooked up to an outdoor power outlet. It includes a monitoring hub and software that didn't work initially. Learned a lot from this review [Admin: link removed]
I decided to reconsider.