Sanyo Bifacial Solar Panels

[BlueSovereign]

A while back, there was a thread that mentioned the above (see attached).

Has anyone investigated these or has installed these? What do you see as their pros and cons?

[witzgall]

A couple of things I noticed about these panels:

1. They are quite large
2. They are I think 48v nominal, so your controller options are more limited.
3. The benefits of the dual sides would be only beneficial if they were above some kind of reflective surface, such as hanging over the water. If you have a largearch or davits, they might provide some additional output. I would imagine that you would ahve to careful about blocking the panel's access to the sun from below, as well as from above.

Chris

[Free Lancer]

Originally Posted by witzgall

A couple of things I noticed about these panels:

1. They are quite large

Chris

i dunno if theres any real effective "small" cells commercially available, but having larger panels would be a draw for me

[kimm]

i installed 3 190w sanyo bifacials on my boat... they are wonderful... i picked them up because i wanted to integrate them into the coverage over the cockpit... they look beutiful from the underside and there build quality is very nice... if the size works for you they are the best panels out there and they make the boat look better not the usual eye sore panels can be...

best of luck...

[Endojoe]

Sounds like a really neat and efficient setup!! How did you integrate them into the cover? Custom fabricated frame? Any pictures?

[kimm]

I designed an arch to support 3 of them and am getting a custom bimini cover integrated into the panels (part panel and part canvas)… I will be away from my boat for a week or so… if still interested by then I can take a pic and post it… the canvas will be a month or so till complete, but the panels have been up and working well for about 4 months. with 3 of them there is more power then i can ever use, even with the water maker running for many hours every day...

[witzgall]

Yes, please post photos and as much details as you can - this sounds really cool!

Chris

Originally Posted by kimm

I designed an arch to support 3 of them and am getting a custom bimini cover integrated into the panels (part panel and part canvas)… I will be away from my boat for a week or so… if still interested by then I can take a pic and post it… the canvas will be a month or so till complete, but the panels have been up and working well for about 4 months. with 3 of them there is more power then i can ever use, even with the water maker running for many hours every day...

[GordMay]

See the interesting recent (2009) Engineering thesis, by Raymond Dong:
“Optimizing Reflection and Orientation for Bifacial Photovoltaic Modules”
➥ https://kb.osu.edu/dspace/bitstream/...ond_Thesis.pdf

[camaraderie]

Thanks for that link Gord...that was a most interesting paper.
Aside from the Bifacial panels I think the most surprising point was the amount of loss in a panel due to even MINOR shading.

"The reduction in PV module power output is proportional to the area shaded for any one solar cell or any string of cells (Kyocera Solar, Inc., 2004). As illustrated in Figure 3, shading half of one cell or half of a string of cells reduces the power output by 50%."

This certainly argues against bimini mounts!

[witzgall]

This is so true for Mono or Polycrystalline panels. Some have diodes in-between the cells, which should help reduce this problem. I have seen so many boats with panels put up on arches, and multiple antennas surrounding the panels, ensuring that whatever the sun's direction, the panel will have partial shading. Shrug.

I just mounted our two 120w panels up on our arch. It might not be the prettiest, but there is no shading possible other than from the rig/sails. I have a donated Airx, but before I mount it, I plan on doing some testing on shading by temp mounting it and taking measurements throughout the day with and without the generator in place. I hope there is not much of a drop in output, but I think that will prove to be wishful thinking.


Chris

Originally Posted by camaraderie

Thanks for that link Gord...that was a most interesting paper.
Aside from the Bifacial panels I think the most surprising point was the amount of loss in a panel due to even MINOR shading.

"The reduction in PV module power output is proportional to the area shaded for any one solar cell or any string of cells (Kyocera Solar, Inc., 2004). As illustrated in Figure 3, shading half of one cell or half of a string of cells reduces the power output by 50%."

This certainly argues against bimini mounts!

[MarkJ]

Originally Posted by witzgall

I have a donated Airx, but before I mount it, I plan on doing some testing on shading by temp mounting it
Chris

Hey Chris, If you mount the AirX on someone elses boat then we will come park next to you at an anchorage... otherwise.....
Gotta luv solar because its so quiet... just sits there doing its job.

The funniest thing about wind generators are that the owners can never hear them A couple times folks have said "we turn it off when we have guests". Then we jump on board and they leave it ON! Are they trying to get rid of us that quickly??? Haven't even started drinking their beer yet

We have had our 120 watt monocrystaline for 3 days now and havent used the engine yet Its just resting on the deck, partially shaded at times, waiting till be get it properly mounted. We get the second pannel next week... that one will get its own cabin till mounting.

2x120 watts and we will have more electricity than we know what to do with! YIPPEE! Stuff more junk in the fridge! Or maybe get a freezer!!!! <--- Damn, overshot my dreams



Mark