Once again thanks for making these videos. It takes a ton of time to gather data just for a "quick" video. Thanks for all the time that you put in on the backend!
I like the data-driven approach. I know some folks hate to say percentages and relative differences and analysis but I don't like "rule of thumb" statements when you could have data. I also like you have shown clearly how that data was acquired. Kudos to you, good stuff, keep it going
This panel can put out close to 100 watts th-cam.com/users/postUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.
I just read a study on bifacials that showed that the best possible positioning is to align them east/west and perfectly vertical. It produces more total power, and does so over a much wider time period. The trick of course is the wind loading, but it's doable and makes a lot of sense as secondary panels to expand your harvest.
I have had a lot of requests for vertical orientation of bifacial panels, I plan to work on a test setup to try that out, but it will take a long time to get a full season of data.
Great point James! I read a similar article that used bifacial panels in this way; but also used the terrain & weather (foggy) conditions to their advantage! They used water collecting nets above the panels (some also below for comparison) and produced not only more power but also got the efficiency gains of cooler panels!!! Gotta love our innovative minded people coming up with these adaptations!!!
Find More information for this project and others on my website: projectswithdave.com Affiliate links for two great sources for solar panels, thanks for supporting the channel: Great Value Panels from Signature Solar: signaturesolar.com/shop-all/solar-panels/?ref=SALE Clearance Panels from SanTan Solar: www.santansolar.com/product-category/solar-panels/?ref=EverydayDave Current deal while supplies last on $0.57/Watt 460W Bifacial BlueSun: signaturesolar.com/bluesun-460w-half-cell-bifacial-solar-panel-silver/?ref=SALE I have only tested the Canadian Solar Bifacial panels, but they are often out of stock.
I already have some data. It takes a long time to pull it all together into a video. First look at the data says snow is a great reflector! Unfortunately snow doesn't stay on the ground long here.
Big THANKS for this review! I understood the logic, but seeing the performance advantage is fantastic! Now will definitely look at BF! A couple of months ago I was at the Mercedes Benz stadium in Atlanta, GA, its east parking lot is covered with frame-less BF panels. Looked awesome! Took some photos of it.
So excited for the video!! Thanks for the real testing! First thing that comes to mind (even before watching the whole video) thermal coefficiency 🤔 +plus light refraction off structure 🤔. Ahhh data 🌄😁👍
In your prospective tests with your Bi-facial panels, could you test vertical placement? I have seen reports that vertical placement on an East/West orientation produces more energy than panels with tracking.
Thx for all your work and sharing of information. I appreciate any and all accurate information about solar setups. I believe, in the interest of simplicity, the data provided is a good reference. Your/ my mileage may vary. In this example, I believe the rack should be moved up so the white is totally under plus 6-12" or more. The lack of reflection on the lower edger could essentially make the bifacial portion almost useless. Also, ignoring the 3rd panels, skews the data. Averaging power is a start, but individual panel performance is more inclusive. I am waiting on getting a pallet of new bifacial panels. Will be roof mounting most. May update afterwards.
So for this test if you were to lift the bifacial panels a meter or so, and have them on a ground mount preferably, You would absorb a lot more energy from the backside. This is mentioned multiple times in the literature, And I mentioned this in past videos. The temperature coefficient of those bifacials is also different. So more convective air flow helps significantly. A parking structure is fantastic for bifacials. They really need to be lifted up high to see the benefits. In your configuration they will run a bit hotter than they should and they will not absorb much energy from the back.
That's correct, the purpose here was to show what kind of performance could be expected from a standard mount on a white roof. The higher elevation would be much better for all the reasons you mentioned. Ground is a better application for bifacial panels as I show in my ground array results video: th-cam.com/video/1SXNjsSsmq0/w-d-xo.html Also, I have done some testing with snow reflection on my ground array, I hope to post soon. Those results were very good.
Hi Will, would you say mono panels would be a better choice for a flat RV roof? Comparing 2 panels (bifacial 610watts with 2mm glass and 590w mono panels with 3.2mm glass) would the mono be a better choice for more resistance against elements? Basically same price for both. Would be installed on a white painted roof and with just 10-20cm separation from the roof.
for rural consumers like myself, with plenty of white pole barn roof to work with, it sounds like it might be the way to go, especially as the price for bifacials keeps coming down. spread them out a little, mount them up off the roof some, and i want to put mine on angle adjustable bases so i can tweak the angle throughout the year.
i think the fact that they are made in canada ,, they figured out a way to maximize the panels for our winters,, at 60 degrees and snow on the ground , these bifacials will help offgridders in canada during the winter months when we get less sun and need roughly the 60 degrees of angle ,,this allow more light to get behind the panels
For me the comparison between output power and cost is the most important. If the cost of the bi-facials are 120+% greater, you would be better off installing more regular panels, unless you can meet all the added conditions to optimize bi-facials.
Great videos. Thank you. I don’t agree with you though when you calculate paybacks periods and ROI based on the system production. What counts is your actual solar consumption you don’t buy from the utility grid. And both numbers (production and consumption) are usually far from each other.
I have to purchase any power I don't produce from the utility. That cost avoidance is used to calculate the payback period. If I am overproducing, then the values change significantly as does the payback period. It all depends on your specific situation.
this was exactly the video I was looking for. For me, the cost payoff doesn't seem to justify bifacial plus real estate on my roof is precious. I guess Bifacials are not for me!
Great video. Aluminized reflective roof paint. I'm about to put bifacial panels on my black asphalt roof.... they're priced the same or cheaper than similar standard panels now so why not....and plan to paint the roof with aluminized paint that reflects 90%+ of sunlight that hits it. So I'm hoping that 62 dollars in paint will help push my panels into performing similar to yours. Cheers!
I saw a video that said the tiny spacing between cells in a bifacial panel was transparent and light the would strike between cell on a standard panel would hit the roof and be reflected back to the back of the bifacial.
Some panels are transparent and some are not. The Canadian Solar panes in this video have a white band that blocks the light between the cells. I just ordered some panels that are transparent in the space between the cells. I plan to do some testing and see if it makes a difference.
@@ProjectsWithDave I saw a TH-cam video involving an installation in Britain where the transparency was pointed out. Hopefully it can actually increase absorption on the underside.
like your thoughts on bi-facial panel ground mount at 23 degree off due south set at a 40 degree slope in central Ohio and is tall enough for light to be reflected off white steel siding on a building running true east west. your videos are very informative. thank you for making them and the work your doing to gather the data to make them.
Thanks a ton for this, Dave. Can you pls reflect on heating properties/resistance, esp. during the hottest periods and the resulting drop of performance.
I haven't captured the data specifically necessary to analyze the performance relative to temperature. I may do that sometime in the future, meanwhile, there is a lot of generic data out there on the temperature effects if you search for it. Here is one for reference: solarpoweredblog.com/how-does-temperature-affect-solar-panels/
hello good video , Itest different direktion of vertikal bifacial panels on a fens and I think the best result will be south vest diretion becouse the sun will have better angel on the afternoon
I want to install 100kwh bificial topcon module on metal roof of my factory with 125mm clearance. Will it increase heat between module and roof? Will it affect power generation due increase in heat? Should I install on bificial module on metal roof?
a W shaped reflector at twice the width of bifacial panel would give you near full sun both sides. would be nice to see clouldy day output from this setup.
How did you do a comparison with that shade hitting your bottom row? Also, did you even consider temperature coefficients between panel types? That, alone, can produce dramatic difference between two panels with identical DC-STC ratings. Also position in the array can make a difference due to heat (and reflection, which you noted). Best way to do this experiment is with the same panels... matched for output and then do two separate arrays (sans shade) and black out the backside on one array so no reflected light reaches the cells. Comparing different types of panels by the generic category of monofacial vs bifacial is just not going to give you what you're after.
I have two dual axis solar arrays of 3140 watts of panels per tracker. The panels are 390 watts each and are bifacial the ground surrounding them is a white reflective stone in order to maximize the reflective light. The best performance I have seen is around 3372 watts per array which was limited due to my MPPT controller.
Because you don't know what the solar irradiance was at the time of your measurement, and your inverter was clipping, it's hard to judge what the actual benefit is. However, in my experience, conventional panels have to be significantly over 1,000W/m^2 to exceed their rated performance so it sounds like your setup is doing quite well.
I am interested in using vertically mounted bifacials in the winter in south Alaska. But I have been able to find absolutely nothing on the effects of vertically mounted bifacial performanc in or out of snow weather and nothing on their performance in low lighting which seems to be their chief advantage as promoted.
ATTENTION: you missed a major point in conclusion in my opinion cause the bifacial have a better protection and longevity cause both sides are protected by glas. The small white foil will age not so well and once humidity gets in the corrosion will start and production decrease a lot. I had such issues with a trina solar panel field and you could see the progress of holes in the foil than getting bigger over time while also building oxidations on the cells itself. You can even feel them. This can not happen with such bifacial panels and that can be worth a lot. You do not know what not can cause the damage of the foil like cleaning the roof with a Kärcher, also animals running under panels, then wind with sand and what not will have an impact and can damage a single panel and have a huge impact over time cause you will not recognise the slowly decrease over time in a long string. Maybe a year or 2 later you will wonder and compare month to months and start a research what is going on. Many then consider degredation as the cause , I mean degredation of the whole field. And if another year or 2 pass by they might start offcially complaining and learn that it needs a labour intensive investigation on the roof for that string panel by panel cause it could be just 1 panel that has issues and not all of them cause then the solution is usually easy: remove the weak and broken one and shorten the string cause you will not get a replacement of the same size and characteristics as long as you have luck to find one or usually some on the used market over time. Glas Glas is the best you can get and it will pay off for sure but might take some years. The degredation or the likelihood of damages are lot lower than those with a thin foil . But I am from the EU and we might have different products and experiences here due to climate and what not. I do not see it often, but I bet many do not know after 12 years or so that a single of these panels could have caused all the losses what they considered to be caused by degredation of the whole string , not a single panel. They do not even recognice it cause no one investigates the back of these panels in the assumption if a hole in the back of 1 panel could have caused the whole decrease over the past 2 years. But we had repowered a lot of roofs in a small period of time last year and faced a lot of these or similiar issues mainly caused by a single panel - also MC4 connectors that lost its perfect fit and connection. We try to look for that cause if you wanna sell used panels with faith you should know what you are selling and therefore we marked every single panel to later find out if we could see an impact when and where what might have started. We have to check the modules any way but it was the first time that we faced a lot issues with damaged foils no one can explain how that could have happened. Partly while carrying the panels onto the roof, then during mounting, connecting , fixing, adjusting by any kind of accident like a screw driver falling onto the shoes then hitting the panel under the foil. No one had taken care for that. Might also be the case of micro holes or scratches the winter and frozen water increased and what not. The worst panels with a ton of issues were the Trina panels 240 Wp from 2014 or so. 50% with one issue or the other and mostly oxidation under the white foil.
I ran a back to back test between Canadian Solar and Q-Cell Bifacial panels, but unfortunately, The data was lost on the server. I hope to give it another shot this summer then I will have some data between brands to see if there are significant differences. I expect you will be happy with them.
I think those bifacial panels do have another significant advantage: They have half cut cells. Those are by themselves a very awesome innovation in PV technology. Did you factor that in?
@@ProjectsWithDave I don't think it has to be pitched alot. Maybe 10 deg. Enough to allow a bit more light to reflect off of the white roof. You might get some reflected light off of the opposing panel
You could always set up a few panels and try it. Keep in mind the sun changes quite a bit from the winter to summer solstice so you need to run your test for about 6months to get the full result.
excellent video, thanks for posting. How high above the roof are the bifacials mounted? I mean are the bifacials mounted directly to the roof like the regular panels or is there some space between the bifacials and the roof?
Thanks for the video Dave. I really enjoy your stuff. With that said I have a hip roof house light color asphalt roof with a dormer so real estate on the roof is at a premium. So which solar panels have the most watts per square foot output?
What if you layered them? What distance would be detrimental to the one behind the first? Would the second panel reflect enough light onto the back of the first one? Would it even matter at all?
Thank you. Considering the panel is about 10% bigger, we get more or less the same output. For me personally it doesn't make much sense buying these with extra liability.
I'm looking to do a solar set up on my boat and im just now finding out about these. I have a hand rail around the back of the boat i want to have the panels pivot on, like a butterfly, so i can fold them down while underway. My question is, if im comparing a bifacial to a regular panel, does the bifacial NEED exposure on the otherside to get its full output? Or will just the one side produce the same as a regular and the back side is extra? I think my biggest benefit would be water reflection on the back.
Most bifacial panels are rated by the front side output. The back side is just bonus. Here is a video with more detail: th-cam.com/video/1SXNjsSsmq0/w-d-xo.html
Great details on the data. Looks like you had more issues with the inverters producing power then the panels generating it. It would be interesting to see the same data from you solaredge or getting enphase inverter. A chain is only as strong as the weakest link. Are you going to do more testing with the Sungold IP6048? I have that inverter with eg4 batteries and I'm going to add some bifocal panels in later this year. I'm interested if your going to program the invert with the front panel or the laptop software and if you'll get the phone app working.
It's on my bench, I plan to expand my main array and support the expansion with the SunGold inverter. Will Prose seemed to struggle programing his with the panel, so I'll likely use the software.
Aren't BF panels degrade less overtime? That's what I heard about them and why people chose them. But for me they mostly make sense for ground arrays with some reflective material beneath them
the mixed bifacial and standard panel produced the least? interesting!! i wanna know the data on why because i have mixed panels on mine, a 400 mono and a 300 watts poly. voltage are close together with a 2 amps more on the mono. please make that video possible.
I believe, when the voltage and current ratings don't match the inverter ends up taking the lowest common denominator. I don't recommend having mismatched panels on the same inverter input.
we shuld install bifacials on grnd or on roof and kindly suggest the better one and which tyoe of colored shuld be better for roof installation white or darker one?
I don't think bifacial panels are necessarily larger. The 445W bifacials I just received are slightly smaller than those ones you are using. I think you just have lower binned solar cells.
If you compare equivalent cells, just due the the physical layout of the cells, some area is lost. Notice the large bands of unusable space between each cell and down the middle. It may be less of an impact on some brands than others.
@@ProjectsWithDave Being a solar cell scientist/engineer, I am very surprised about the 10% higher energy, which in your case should be equal to 10% higher energy yield (kWh/kW), is huge. If it’s true, everyone should paint their roof white and put bifi panels.
I have a similar building (larger, but with a similar roof pitch and south facing). We live in Western Washington so I'm thinking that it will help on the cloudy days. Is there a racking system that will get them up higher off the roof to maximize the bifacial efficiency? Or is it that a wind concern?
Iron Ridge has a rack system with standoffs of various lengths. But, the tallest standoff that is engineered for a "sloped" roof is 7" including mount. If youre not concerned with approvals and permits than the skies the limit. At your own risk of course:) I know the bldg dept here pays attention and wants everything spec'd. I have a 4/12 roof and also want to install bifacial raised. The roof is galv metal and very reflective. I may still do it and leave spacing between each row. If, the panel price makes sense.
If the bifacials are on a string inverter, 4 x 3 array, and the middle panels do not get any reflection advantage and the end panels do, dont the middle panels prohibit the end panels from increasing total kw output? In other words, are micro inverters required to take advantage of bifacial gains of the end panels in a 4 x 3 panel array that is installed on a roof similar to the video?
To some extent, yes. The micro inverters are better at taking advantage of small differences in individual panel output. However, I don't think it would be terribly significant in the whole scheme of things.
Hi Dave, vivek here from solar forum. As promised I purchased two 550w bifacial panels which claims for 30% gain, so totals upto 1360 watts. I have to lot to find out, but from solar atlas I figured out I need to install at 26° acc to my latitude. My question is, is that angle is for normal panels and bifacials need to be more tilted as suggested in video? I can install them as higher as possible, but can you give me any figures based on height so I know at how much height I should install them, or is it the highest the best? Third question I have is, from which direction the light reaches to the 2nd face of the panel. Because based on this I can decide at what place in my property I install these panels, does the light enters from the front or from the back?
The front of the panel should face the sun. You can go to ( pvwatts.nrel.gov/ ), and run simulations for different tilt angles and orientations. That will tell you your average production for each month. Then orient your panels to best fit your actual consumption needs. I use the tool in this video on sizing your solar array: th-cam.com/video/rbFnZqA0GCI/w-d-xo.html
@@ProjectsWithDave hey, need a quick help! my installer is insisting on installing those bifacial panels at a very low height due to difficulty in installation at the flat roofs here in India. They says the front will be at around 1.5feet height and at 26 degree tilt, the back part will be at 4.5 feet, do you think this will generate any energy from the back? or should I force him to increase a little bit more? Thankyou
It might consider adding a white colored metal roof over the top of the shingles in the area that you plan to install the panels. However, it’s probably not financially feasible. In my humble opinion you should just stick with the regular panels. I think bifacials are still best in a freestanding array setup to allow maximum reflective light penetration.
Yes, bifacials shine best on a ground array. However, If you have a flat white roof and mount the panels at an angle I think you would see good performance there as well.
It appears that those bifacial panels are flat on the roof and from what I understand they need to be lifted up as a matter of fact a 90° angle is ideal because it gets the Sun from both sides. From the technology of bifacial panels I would think they would not be good on a roof unless you could severely lift them up which I think would be a wind Hazard unless it's a flat roof. Flat on the roof as they are in the picture will cause them to heat up and bifacial panels generate less wattage the hotter they get.
The purpose of this test was to show the performance of the panels when mounted parallel with the roof. They would certainly perform better if mounted at an angle to the roof.
Just out of interest, have you practiced in general/practice for each video the gestures you use while speaking? It feels very deliberate, and I recognise many of the common gestures taught by coaches, just wondering if it's a conscious process to work them out, an acquired and internalised skill, or just a natural thing you do without training of any kind?
😂 That's funny. My wife makes fun of me for my hand gestures. I think it's a result of living in Brazil when I was a child. I had to use a lot of hand motions to get my point across because I didn't speak the language very well. Now it just seems like a necessary part of communication.
I don't understand why someone would mount bifacial panels side by side without a gap. There is not much light coming in onto the white backside to reflect. Leaving gaps would greatly improve that.
I am asking everybody for a solution with no response. I want to charge my 12v 200 amp battery and run 300watt 12v load at the same time. People on TH-cam put panels and load parallel on the battery, which drops the voltage and the battery never gets fully charged. What is the solution to run DC load and charge battery simultaneously.
I built a simple 12V system in this video: th-cam.com/video/OwfGLu8IY_M/w-d-xo.html If you don't need the inverter, you can just eliminate that part of the build. The charge controller can charge the batteries and allow you to run a DC load off the battery at the same time.
Costing at the moment makes rhem worthless. They are 500w panels in market, sold as 650w due to being "30%" better because they are bifacial. A 550w mono-facial at nearly 80% less, it is a no brainer.
Do you have any plans to try out a mirror below a bifacial panel? Particularly for roof mounted. A video was recently posted about scientists doing this with perovskite cells to boost efficiency: th-cam.com/video/BtOSAOaAmUM/w-d-xo.html
Adding a physical mirror below the panels would be a completely different phenomenon than the one described in the video above. However, I do hope to do some mirror experiments when I find some time.
@@ProjectsWithDave When I first commented I hadn't thought to ask if the bi-facial panels are opaque or semi-transparent? I remembered you said they had a glass backing, is that lined so light has to be shone on the back, or can it pass through the panel? Thanks for your comprehensive videos
A little bit of Googling revealed the liner is not present in bifacial panels, just a glass sandwich. I wondered if mounting mirrors below on roof panels would amplify the output, giving it a second bite of the cherry so to speak, with the reflected light. Keen to see your results, thx.
I don't think mirrors directly behind the panels would be a significant improvement. In a roof setup not much light reaches behind the panels to be reflected. That's why they work best in a ground array.
👍 Thanks, that was enlightening. Maybe you can get some help with your runaway hands someday, very distracting, especially when you insisted on sticking a full shot of yourself over to the side when showing panel results. Try to get some help with that narcissism while you're at it.
Thanks for the feedback. I lived in Brazil for a while as a child. Since I didn't know the language very well, I got used to using my hands to augment what I was trying to say. Sorry it's distracting for you.
I think ground mount would be best. But not off the ground. Simplify. Its supposed to be green, so why are we using tons of steel or aluminum (NOT GREEN) to mount the panels??? Take a square section. Plot rows for the panels, make square or rectangular area into a gravel pad. Use white gravel for bifacial, or something like it. I think white lava rock would be so cool but not cheap. Limestone? Probably crushed marble would be most effective. Put down just a weed barrier, you can use roof water seal tyvek or the like. And then just fill with nice amounts of rock. Marble white rock to be precise. Make a harness for your arrays from legit solar wire, solder silicone and heatshrink the splices its EASY. And it works great. Anchor the front panels with a type of stake, like drive in long rods, use whatever works, rebar probably ok for the front low edges. And maybe even rebar for the rear. I would go with 1 inch galavnized pipe from a trampoline or tent or something like that. Salvaged smartly. Easy to clean and maintain. Risk of fire is low. Risk of panel damage is lower because you can actually cover them easy. WIth big tarp, the center panels always have the tarp draped to protect. Risk of panels flying off is low when you install correct. You could even do small concrete mortar infill to be legit. I would use a barbed driven spike. Stainless wire tie them down. If its good enough for an airplane... Then trench just to the edge of the gravel and have the plugs right to your disconnect. Nothing expensive or demanding. Plus the bifacial, AND white gravel reflectivity could actually increase the advantage by 35 percent, comparing to standard black roof vs white gravel, vented, bifacial. Long term cleaning is easier, so more output. And lifespan increases because they are coolest, with just about the max possible amount of air circulation and light reflectivity. Also a white driveway works this way too, I think car port bifacial solar installs would be another great standard model. A bit more material demand, but, if its just 2 inch galvanized pipe, its fairly cheap. I would do it either way personaly if I had the need.
Once again thanks for making these videos. It takes a ton of time to gather data just for a "quick" video. Thanks for all the time that you put in on the backend!
Yes, months of data and hours of analysis. Thanks for noticing!
Yes, thank you so much! This was so valuable!
Thank You for supporting Solar and for All that you are doing for our Planet Earth....
Peace.. Shalom.. Salam.. Namaste 🙏🏻 😊 🌈 ✌ ☮ ❤
I like the data-driven approach. I know some folks hate to say percentages and relative differences and analysis but I don't like "rule of thumb" statements when you could have data. I also like you have shown clearly how that data was acquired. Kudos to you, good stuff, keep it going
Well balanced data and review on BF panels, thank you for sharing both sides (pun intended)!
This panel can put out close to 100 watts th-cam.com/users/postUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.
I just read a study on bifacials that showed that the best possible positioning is to align them east/west and perfectly vertical. It produces more total power, and does so over a much wider time period. The trick of course is the wind loading, but it's doable and makes a lot of sense as secondary panels to expand your harvest.
I have had a lot of requests for vertical orientation of bifacial panels, I plan to work on a test setup to try that out, but it will take a long time to get a full season of data.
Great point James!
I read a similar article that used bifacial panels in this way; but also used the terrain & weather (foggy) conditions to their advantage! They used water collecting nets above the panels (some also below for comparison) and produced not only more power but also got the efficiency gains of cooler panels!!!
Gotta love our innovative minded people coming up with these adaptations!!!
@@ProjectsWithDave That would be very interesting! I've thought about doing a BF panel fence line if I ever feel the need to expand my system.
Ya, I was was wondering why this guy had them set up wrong. This guy wasted his own time and everyone's who watched this by laying them down.
Find More information for this project and others on my website: projectswithdave.com
Affiliate links for two great sources for solar panels, thanks for supporting the channel:
Great Value Panels from Signature Solar: signaturesolar.com/shop-all/solar-panels/?ref=SALE
Clearance Panels from SanTan Solar: www.santansolar.com/product-category/solar-panels/?ref=EverydayDave
Current deal while supplies last on $0.57/Watt 460W Bifacial BlueSun: signaturesolar.com/bluesun-460w-half-cell-bifacial-solar-panel-silver/?ref=SALE
I have only tested the Canadian Solar Bifacial panels, but they are often out of stock.
Probably the best series of videos on the topic thank you.
Great video, thanks. I was expecting the results, but it is great to have them backed up by data.
I have been looking forward to these results. Can’t wait to see the results of the freestanding solar array with a snow reflection!
I already have some data. It takes a long time to pull it all together into a video. First look at the data says snow is a great reflector! Unfortunately snow doesn't stay on the ground long here.
@@ProjectsWithDave thanks for the countless hrs that you put in to share these videos and data with us!
Thanks from sunny Baghdad :)
Great analysis and really like how you present the problem and data, very helpful.
Thanks! Glad it was helpful!
Big THANKS for this review! I understood the logic, but seeing the performance advantage is fantastic! Now will definitely look at BF!
A couple of months ago I was at the Mercedes Benz stadium in Atlanta, GA, its east parking lot is covered with frame-less BF panels. Looked awesome! Took some photos of it.
Glad it was helpful!
Wow just started your videos.. your data is exactly what I’m looking for.
So excited for the video!! Thanks for the real testing!
First thing that comes to mind (even before watching the whole video) thermal coefficiency 🤔 +plus light refraction off structure 🤔.
Ahhh data 🌄😁👍
Thanks!
I just found your channel and wanted to thank you for this excellent content... subscribed.
Awesome, thank you!
In your prospective tests with your Bi-facial panels, could you test vertical placement? I have seen reports that vertical placement on an East/West orientation produces more energy than panels with tracking.
And no snow covering the panels either
Thx for all your work and sharing of information.
I appreciate any and all accurate information about solar setups.
I believe, in the interest of simplicity, the data provided is a good reference. Your/ my mileage may vary.
In this example, I believe the rack should be moved up so the white is totally under plus 6-12" or more.
The lack of reflection on the lower edger could essentially make the bifacial portion almost useless.
Also, ignoring the 3rd panels, skews the data.
Averaging power is a start, but individual panel performance is more inclusive.
I am waiting on getting a pallet of new bifacial panels. Will be roof mounting most. May update afterwards.
Let me know how it goes.
So for this test if you were to lift the bifacial panels a meter or so, and have them on a ground mount preferably, You would absorb a lot more energy from the backside. This is mentioned multiple times in the literature, And I mentioned this in past videos. The temperature coefficient of those bifacials is also different. So more convective air flow helps significantly. A parking structure is fantastic for bifacials. They really need to be lifted up high to see the benefits. In your configuration they will run a bit hotter than they should and they will not absorb much energy from the back.
That's correct, the purpose here was to show what kind of performance could be expected from a standard mount on a white roof. The higher elevation would be much better for all the reasons you mentioned. Ground is a better application for bifacial panels as I show in my ground array results video: th-cam.com/video/1SXNjsSsmq0/w-d-xo.html
Also, I have done some testing with snow reflection on my ground array, I hope to post soon. Those results were very good.
Is there a roof racking system that will raise them higher or is that a wind concern?
Hi Will, would you say mono panels would be a better choice for a flat RV roof? Comparing 2 panels (bifacial 610watts with 2mm glass and 590w mono panels with 3.2mm glass) would the mono be a better choice for more resistance against elements? Basically same price for both. Would be installed on a white painted roof and with just 10-20cm separation from the roof.
This was nerdy. Thanks alot. Subscribed
for rural consumers like myself, with plenty of white pole barn roof to work with, it sounds like it might be the way to go, especially as the price for bifacials keeps coming down. spread them out a little, mount them up off the roof some, and i want to put mine on angle adjustable bases so i can tweak the angle throughout the year.
i think the fact that they are made in canada ,, they figured out a way to maximize the panels for our winters,, at 60 degrees and snow on the ground , these bifacials will help offgridders in canada during the winter months when we get less sun and need roughly the 60 degrees of angle ,,this allow more light to get behind the panels
I think bifacial panels are the best improvement in solar panels since half cut cells.
For me the comparison between output power and cost is the most important. If the cost of the bi-facials are 120+% greater, you would be better off installing more regular panels, unless you can meet all the added conditions to optimize bi-facials.
Great videos. Thank you.
I don’t agree with you though when you calculate paybacks periods and ROI based on the system production. What counts is your actual solar consumption you don’t buy from the utility grid. And both numbers (production and consumption) are usually far from each other.
I have to purchase any power I don't produce from the utility. That cost avoidance is used to calculate the payback period. If I am overproducing, then the values change significantly as does the payback period. It all depends on your specific situation.
this was exactly the video I was looking for. For me, the cost payoff doesn't seem to justify bifacial plus real estate on my roof is precious. I guess Bifacials are not for me!
Great video. Aluminized reflective roof paint. I'm about to put bifacial panels on my black asphalt roof.... they're priced the same or cheaper than similar standard panels now so why not....and plan to paint the roof with aluminized paint that reflects 90%+ of sunlight that hits it. So I'm hoping that 62 dollars in paint will help push my panels into performing similar to yours. Cheers!
Leave a gap between the panels for the light to shine through!
@@noneofyourbusiness7651 exactly what my thought was.
I saw a video that said the tiny spacing between cells in a bifacial panel was transparent and light the would strike between cell on a standard panel would hit the roof and be reflected back to the back of the bifacial.
Some panels are transparent and some are not. The Canadian Solar panes in this video have a white band that blocks the light between the cells. I just ordered some panels that are transparent in the space between the cells. I plan to do some testing and see if it makes a difference.
@@ProjectsWithDave I saw a TH-cam video involving an installation in Britain where the transparency was pointed out. Hopefully it can actually increase absorption on the underside.
like your thoughts on bi-facial panel ground mount at 23 degree off due south set at a 40 degree slope in central Ohio and is tall enough for light to be reflected off white steel siding on a building running true east west.
your videos are very informative. thank you for making them and the work your doing to gather the data to make them.
Thanks! I'm glad the data has been useful for you.
Thanks a ton for this, Dave.
Can you pls reflect on heating properties/resistance, esp. during the hottest periods and the resulting drop of performance.
I haven't captured the data specifically necessary to analyze the performance relative to temperature. I may do that sometime in the future, meanwhile, there is a lot of generic data out there on the temperature effects if you search for it. Here is one for reference: solarpoweredblog.com/how-does-temperature-affect-solar-panels/
hello good video , Itest different direktion of vertikal bifacial panels on a fens and I think the best result will be south vest diretion becouse the sun will have better angel on the afternoon
I want to install 100kwh bificial topcon module on metal roof of my factory with 125mm clearance.
Will it increase heat between module and roof?
Will it affect power generation due increase in heat?
Should I install on bificial module on metal roof?
If the roof is white, or a very light color you will see some benefit. If it is a dark color I wouldn't bother.
@@ProjectsWithDave will any heating issue on module bcoz of both side glass?
In U.S. which Module is more popular for metal rooftop Mono perc half cult bificial or n-type topcon
I don't think you will see a significant heat increase with bifacial over standard panels, the sun exposure is almost the same.
a W shaped reflector at twice the width of bifacial panel would give you near full sun both sides. would be nice to see clouldy day output from this setup.
These results are an average of both cloudy and sunny days.
How did you do a comparison with that shade hitting your bottom row? Also, did you even consider temperature coefficients between panel types? That, alone, can produce dramatic difference between two panels with identical DC-STC ratings. Also position in the array can make a difference due to heat (and reflection, which you noted). Best way to do this experiment is with the same panels... matched for output and then do two separate arrays (sans shade) and black out the backside on one array so no reflected light reaches the cells. Comparing different types of panels by the generic category of monofacial vs bifacial is just not going to give you what you're after.
Thanks for sharing.
I have two dual axis solar arrays of 3140 watts of panels per tracker. The panels are 390 watts each and are bifacial the ground surrounding them is a white reflective stone in order to maximize the reflective light. The best performance I have seen is around 3372 watts per array which was limited due to my MPPT controller.
Because you don't know what the solar irradiance was at the time of your measurement, and your inverter was clipping, it's hard to judge what the actual benefit is. However, in my experience, conventional panels have to be significantly over 1,000W/m^2 to exceed their rated performance so it sounds like your setup is doing quite well.
I am interested in using vertically mounted bifacials in the winter in south Alaska. But I have been able to find absolutely nothing on the effects of vertically mounted bifacial performanc in or out of snow weather and nothing on their performance in low lighting which seems to be their chief advantage as promoted.
I've had a lot of requests to do some vertically mounted bifacial panels. When I get some time I'll run some tests on the concept.
@@ProjectsWithDave Awesome! Thanks!
ATTENTION: you missed a major point in conclusion in my opinion cause the bifacial have a better protection and longevity cause both sides are protected by glas. The small white foil will age not so well and once humidity gets in the corrosion will start and production decrease a lot. I had such issues with a trina solar panel field and you could see the progress of holes in the foil than getting bigger over time while also building oxidations on the cells itself. You can even feel them.
This can not happen with such bifacial panels and that can be worth a lot. You do not know what not can cause the damage of the foil like cleaning the roof with a Kärcher, also animals running under panels, then wind with sand and what not will have an impact and can damage a single panel and have a huge impact over time cause you will not recognise the slowly decrease over time in a long string. Maybe a year or 2 later you will wonder and compare month to months and start a research what is going on. Many then consider degredation as the cause , I mean degredation of the whole field. And if another year or 2 pass by they might start offcially complaining and learn that it needs a labour intensive investigation on the roof for that string panel by panel cause it could be just 1 panel that has issues and not all of them cause then the solution is usually easy: remove the weak and broken one and shorten the string cause you will not get a replacement of the same size and characteristics as long as you have luck to find one or usually some on the used market over time.
Glas Glas is the best you can get and it will pay off for sure but might take some years. The degredation or the likelihood of damages are lot lower than those with a thin foil . But I am from the EU and we might have different products and experiences here due to climate and what not. I do not see it often, but I bet many do not know after 12 years or so that a single of these panels could have caused all the losses what they considered to be caused by degredation of the whole string , not a single panel. They do not even recognice it cause no one investigates the back of these panels in the assumption if a hole in the back of 1 panel could have caused the whole decrease over the past 2 years.
But we had repowered a lot of roofs in a small period of time last year and faced a lot of these or similiar issues mainly caused by a single panel - also MC4 connectors that lost its perfect fit and connection. We try to look for that cause if you wanna sell used panels with faith you should know what you are selling and therefore we marked every single panel to later find out if we could see an impact when and where what might have started. We have to check the modules any way but it was the first time that we faced a lot issues with damaged foils no one can explain how that could have happened. Partly while carrying the panels onto the roof, then during mounting, connecting , fixing, adjusting by any kind of accident like a screw driver falling onto the shoes then hitting the panel under the foil. No one had taken care for that. Might also be the case of micro holes or scratches the winter and frozen water increased and what not.
The worst panels with a ton of issues were the Trina panels 240 Wp from 2014 or so. 50% with one issue or the other and mostly oxidation under the white foil.
Another great video, Dave!
I just bought VIKRAM SOLAR 540 WATT SOLAR PANEL Bifacial for $277 on sale normal 330 from AltE i hope they work as good as yours.
I ran a back to back test between Canadian Solar and Q-Cell Bifacial panels, but unfortunately, The data was lost on the server. I hope to give it another shot this summer then I will have some data between brands to see if there are significant differences. I expect you will be happy with them.
I think those bifacial panels do have another significant advantage: They have half cut cells. Those are by themselves a very awesome innovation in PV technology. Did you factor that in?
Not directly. That should not make much difference if there is no shading.
Great info! I wonder if a slightly corrugated layout would increase the bifacial output?
What do you mean by corrugated layout?
@@ProjectsWithDave Collapse the panels like an accordion with the ends and middle seam in the up position. Also spray the roof with reflective mica
If I'm picturing that correctly, you would end up with the panels shading each other and that would reduce output.
@@ProjectsWithDave I don't think it has to be pitched alot. Maybe 10 deg. Enough to allow a bit more light to reflect off of the white roof. You might get some reflected light off of the opposing panel
You could always set up a few panels and try it. Keep in mind the sun changes quite a bit from the winter to summer solstice so you need to run your test for about 6months to get the full result.
Thanks, Dave now I know that my next roof will be metal and White.
😀
excellent video, thanks for posting. How high above the roof are the bifacials mounted? I mean are the bifacials mounted directly to the roof like the regular panels or is there some space between the bifacials and the roof?
There's about 4" to 5".
Thanks for the video Dave. I really enjoy your stuff. With that said I have a hip roof house light color asphalt roof with a dormer so real estate on the roof is at a premium. So which solar panels have the most watts per square foot output?
Thanks! You will probably have to make a simple spreadsheet, input the output and dimensions of your top panels to calculate the comparison.
What if you layered them? What distance would be detrimental to the one behind the first? Would the second panel reflect enough light onto the back of the first one? Would it even matter at all?
Layering them would almost completely eliminate the output from the shaded panel.
Thanks. Very informative.
Glad it was helpful!
Thank you. Considering the panel is about 10% bigger, we get more or less the same output. For me personally it doesn't make much sense buying these with extra liability.
Awesome video! Very helpful. Thanks!
I'm looking to do a solar set up on my boat and im just now finding out about these. I have a hand rail around the back of the boat i want to have the panels pivot on, like a butterfly, so i can fold them down while underway. My question is, if im comparing a bifacial to a regular panel, does the bifacial NEED exposure on the otherside to get its full output? Or will just the one side produce the same as a regular and the back side is extra? I think my biggest benefit would be water reflection on the back.
Most bifacial panels are rated by the front side output. The back side is just bonus. Here is a video with more detail: th-cam.com/video/1SXNjsSsmq0/w-d-xo.html
What is the degree tilting for that set up?
Great details on the data. Looks like you had more issues with the inverters producing power then the panels generating it.
It would be interesting to see the same data from you solaredge or getting enphase inverter.
A chain is only as strong as the weakest link.
Are you going to do more testing with the Sungold IP6048? I have that inverter with eg4 batteries and I'm going to add some bifocal panels in later this year. I'm interested if your going to program the invert with the front panel or the laptop software and if you'll get the phone app working.
It's on my bench, I plan to expand my main array and support the expansion with the SunGold inverter. Will Prose seemed to struggle programing his with the panel, so I'll likely use the software.
Aren't BF panels degrade less overtime? That's what I heard about them and why people chose them. But for me they mostly make sense for ground arrays with some reflective material beneath them
I haven't compared the degradation relative to standard panels, but they have an advantage in just about every consideration.
Im going to install some either side of my sailboat.
They will have 1.7m between the back of the panel and the water line.
Should he interesting
That's a great application for bifacial panels. The water will provide significant reflection to the back side of the panels.
Well done, very informative
Hello Dave! What happend if you put this bifacial panel on red roof? My roof is with red tile, and i think to put bifacial panels on it. Thanks!
It would not be as good as the white roof. I can't say by how much.
the mixed bifacial and standard panel produced the least? interesting!! i wanna know the data on why because i have mixed panels on mine, a 400 mono and a 300 watts poly. voltage are close together with a 2 amps more on the mono. please make that video possible.
I believe, when the voltage and current ratings don't match the inverter ends up taking the lowest common denominator. I don't recommend having mismatched panels on the same inverter input.
we shuld install bifacials on grnd or on roof and kindly suggest the better one and which tyoe of colored shuld be better for roof installation white or darker one?
Bifacial panels perform best on the ground. If you have to put them on the roof, a white roof will perform the best.
@@ProjectsWithDave kindly suggest the position of panel for instal?
Hello, did you use a galvanized steel structure and bolts to assemble the PV panels?
It is an aluminum rail system.
The Bifacial panels are geared more for tilt mounting. Then the cost benefit is worth it.
I don't think bifacial panels are necessarily larger. The 445W bifacials I just received are slightly smaller than those ones you are using. I think you just have lower binned solar cells.
If you compare equivalent cells, just due the the physical layout of the cells, some area is lost. Notice the large bands of unusable space between each cell and down the middle. It may be less of an impact on some brands than others.
What about the temperature coefficient of the two panels? Are they identical?
Very similar.
@@ProjectsWithDave Being a solar cell scientist/engineer, I am very surprised about the 10% higher energy, which in your case should be equal to 10% higher energy yield (kWh/kW), is huge. If it’s true, everyone should paint their roof white and put bifi panels.
I have a similar building (larger, but with a similar roof pitch and south facing). We live in Western Washington so I'm thinking that it will help on the cloudy days. Is there a racking system that will get them up higher off the roof to maximize the bifacial efficiency? Or is it that a wind concern?
There are systems that can raise it up a but, and they are designed to handle the wind loads, but they usually are engineered for a flat roof.
Iron Ridge has a rack system with standoffs of various lengths. But, the tallest standoff that is engineered for a "sloped" roof is 7" including mount. If youre not concerned with approvals and permits than the skies the limit. At your own risk of course:) I know the bldg dept here pays attention and wants everything spec'd. I have a 4/12 roof and also want to install bifacial raised. The roof is galv metal and very reflective. I may still do it and leave spacing between each row. If, the panel price makes sense.
Have you tried reflective foil sheet under the bi-facial panels instead of white roof?
Sorry, not at this time.
awesome information thank you
Glad it was helpful!
If the bifacials are on a string inverter, 4 x 3 array, and the middle panels do not get any reflection advantage and the end panels do, dont the middle panels prohibit the end panels from increasing total kw output? In other words, are micro inverters required to take advantage of bifacial gains of the end panels in a 4 x 3 panel array that is installed on a roof similar to the video?
To some extent, yes. The micro inverters are better at taking advantage of small differences in individual panel output. However, I don't think it would be terribly significant in the whole scheme of things.
Hi Dave, vivek here from solar forum.
As promised I purchased two 550w bifacial panels which claims for 30% gain, so totals upto 1360 watts.
I have to lot to find out, but from solar atlas I figured out I need to install at 26° acc to my latitude.
My question is, is that angle is for normal panels and bifacials need to be more tilted as suggested in video?
I can install them as higher as possible, but can you give me any figures based on height so I know at how much height I should install them, or is it the highest the best?
Third question I have is, from which direction the light reaches to the 2nd face of the panel. Because based on this I can decide at what place in my property I install these panels, does the light enters from the front or from the back?
The front of the panel should face the sun. You can go to ( pvwatts.nrel.gov/ ), and run simulations for different tilt angles and orientations. That will tell you your average production for each month. Then orient your panels to best fit your actual consumption needs. I use the tool in this video on sizing your solar array: th-cam.com/video/rbFnZqA0GCI/w-d-xo.html
@@ProjectsWithDave hey, need a quick help!
my installer is insisting on installing those bifacial panels at a very low height due to difficulty in installation at the flat roofs here in India.
They says the front will be at around 1.5feet height and at 26 degree tilt, the back part will be at 4.5 feet,
do you think this will generate any energy from the back? or should I force him to increase a little bit more? Thankyou
You will still get reflection at that angle, maybe 10% to 15% depending on conditions.
The temperature has more too do with output....The cooler you keep them the more you get out of them..
Great citizen science. Thanks.
So if you have a darker asphalt roof, are there white/light coatings or overlays you can put down before the panels to help reflect light?
I can't imagine something you could apply to an asphalt roof to make it more reflective that would be durable.
It might consider adding a white colored metal roof over the top of the shingles in the area that you plan to install the panels. However, it’s probably not financially feasible. In my humble opinion you should just stick with the regular panels. I think bifacials are still best in a freestanding array setup to allow maximum reflective light penetration.
Yes, bifacials shine best on a ground array. However, If you have a flat white roof and mount the panels at an angle I think you would see good performance there as well.
@@ProjectsWithDavethinking about that just not sure about drilling into my pto roof
It appears that those bifacial panels are flat on the roof and from what I understand they need to be lifted up as a matter of fact a 90° angle is ideal because it gets the Sun from both sides. From the technology of bifacial panels I would think they would not be good on a roof unless you could severely lift them up which I think would be a wind Hazard unless it's a flat roof. Flat on the roof as they are in the picture will cause them to heat up and bifacial panels generate less wattage the hotter they get.
The purpose of this test was to show the performance of the panels when mounted parallel with the roof. They would certainly perform better if mounted at an angle to the roof.
Does the Flexible Bifacial Solar Panel Exist?
I haven't seen any.
Just out of interest, have you practiced in general/practice for each video the gestures you use while speaking? It feels very deliberate, and I recognise many of the common gestures taught by coaches, just wondering if it's a conscious process to work them out, an acquired and internalised skill, or just a natural thing you do without training of any kind?
😂 That's funny. My wife makes fun of me for my hand gestures. I think it's a result of living in Brazil when I was a child. I had to use a lot of hand motions to get my point across because I didn't speak the language very well. Now it just seems like a necessary part of communication.
You should trim that small tree in front of the panels though to make a better comparison.
It’s an awesome job but most homeowners don’t want their panels sticking up off their roof as opposed to flat
I don't understand why someone would mount bifacial panels side by side without a gap. There is not much light coming in onto the white backside to reflect. Leaving gaps would greatly improve that.
Gaps significantly increase the cost of racking and install.
I'm in SE Ohio, what part are you in?
Central
New sub to help you out. Great info
how many people have white a white roof? not many I would hazard to guess.
A white metal roof...just like what the shop has! 🐺🔧
"Shed some light"
I am asking everybody for a solution with no response.
I want to charge my 12v 200 amp battery and run 300watt 12v load at the same time. People on TH-cam put panels and load parallel on the battery, which drops the voltage and the battery never gets fully charged. What is the solution to run DC load and charge battery simultaneously.
I built a simple 12V system in this video: th-cam.com/video/OwfGLu8IY_M/w-d-xo.html
If you don't need the inverter, you can just eliminate that part of the build. The charge controller can charge the batteries and allow you to run a DC load off the battery at the same time.
Bi-facial panels on a roof have to be elevated minimum of 8” 12-14” better. Looks like yours are mounted lower.
Have you had any bird nesting problems.?..the British seem to always add mesh screens..to perimeters...thx for video...
Not birds, but I do get hornets sometimes.
TLDW: In ideal conditions you'll get a few percent more power production.
Best for 2023 Pro
If you're going to put space between the panels you'd be better off just using standard panels with no gaps.
HOWdy P-W-E-D-D, ...
Thanks for the NUMBERS
COOP
the WiSeNhEiMeR from Richmond, INDIANA
...
Obfuscation strategy seldom fools consumers. Hope it works out for you.
damn its heavy too.
Costing at the moment makes rhem worthless. They are 500w panels in market, sold as 650w due to being "30%" better because they are bifacial. A 550w mono-facial at nearly 80% less, it is a no brainer.
You can get some good deals on bifacial panels from Signature Solar: signaturesolar.com/shop-all/solar-panels/?ref=SALE
Costing?? You mean pricing?
Do you have any plans to try out a mirror below a bifacial panel? Particularly for roof mounted. A video was recently posted about scientists doing this with perovskite cells to boost efficiency: th-cam.com/video/BtOSAOaAmUM/w-d-xo.html
Adding a physical mirror below the panels would be a completely different phenomenon than the one described in the video above. However, I do hope to do some mirror experiments when I find some time.
@@ProjectsWithDave When I first commented I hadn't thought to ask if the bi-facial panels are opaque or semi-transparent? I remembered you said they had a glass backing, is that lined so light has to be shone on the back, or can it pass through the panel? Thanks for your comprehensive videos
A little bit of Googling revealed the liner is not present in bifacial panels, just a glass sandwich. I wondered if mounting mirrors below on roof panels would amplify the output, giving it a second bite of the cherry so to speak, with the reflected light. Keen to see your results, thx.
I don't think mirrors directly behind the panels would be a significant improvement. In a roof setup not much light reaches behind the panels to be reflected. That's why they work best in a ground array.
Make no sense to put one side facing the sun and the other one facing the roof with no space and angle to let light affect it...
Don't get it.
Researching how to get a mirrored roof...
Hmmm that doesn't sound great in a hail storm....
Btw average = avg.
If only you could raise them 4' off the roof.
Decent information, but how many people have or will ever have a white roof? So it's far from actual real world data.
The point was to show a best case scenario for bifacial panels on a roof.
Many people have metal roofs and could paint them white and then install the panels.
👍 Thanks, that was enlightening. Maybe you can get some help with your runaway hands someday, very distracting, especially when you insisted on sticking a full shot of yourself over to the side when showing panel results. Try to get some help with that narcissism while you're at it.
Thanks for the feedback. I lived in Brazil for a while as a child. Since I didn't know the language very well, I got used to using my hands to augment what I was trying to say. Sorry it's distracting for you.
ad shill
I think ground mount would be best. But not off the ground.
Simplify.
Its supposed to be green, so why are we using tons of steel or aluminum (NOT GREEN) to mount the panels???
Take a square section. Plot rows for the panels, make square or rectangular area into a gravel pad. Use white gravel for bifacial, or something like it. I think white lava rock would be so cool but not cheap. Limestone? Probably crushed marble would be most effective.
Put down just a weed barrier, you can use roof water seal tyvek or the like.
And then just fill with nice amounts of rock. Marble white rock to be precise.
Make a harness for your arrays from legit solar wire, solder silicone and heatshrink the splices its EASY. And it works great.
Anchor the front panels with a type of stake, like drive in long rods, use whatever works, rebar probably ok for the front low edges. And maybe even rebar for the rear. I would go with 1 inch galavnized pipe from a trampoline or tent or something like that. Salvaged smartly.
Easy to clean and maintain.
Risk of fire is low.
Risk of panel damage is lower because you can actually cover them easy. WIth big tarp, the center panels always have the tarp draped to protect.
Risk of panels flying off is low when you install correct. You could even do small concrete mortar infill to be legit. I would use a barbed driven spike.
Stainless wire tie them down. If its good enough for an airplane...
Then trench just to the edge of the gravel and have the plugs right to your disconnect.
Nothing expensive or demanding.
Plus the bifacial, AND white gravel reflectivity could actually increase the advantage by 35 percent, comparing to standard black roof vs white gravel, vented, bifacial.
Long term cleaning is easier, so more output. And lifespan increases because they are coolest, with just about the max possible amount of air circulation and light reflectivity.
Also a white driveway works this way too, I think car port bifacial solar installs would be another great standard model.
A bit more material demand, but, if its just 2 inch galvanized pipe, its fairly cheap. I would do it either way personaly if I had the need.