Maximizing Bifacial Solar Panel Output: Low vs High Mount Test

[@everydaysolar]

Calculate Solar Cost For Your Home - geni.us/solar_reviews T-Post Black Bracket - geni.us/PtVn Solar Panel Silver Bracket - geni.us/b5pF T-Post Cap - geni.us/WAzb708 DISCLAIMER: This video and description contain affiliate links, which means that if you click on one of the product links, I’ll receive a small commission.

[@markkovelan436]

Studies have shown that the lower edge of the ground mount bifacials should be at least one meter off the ground for back side irradiance. This also helps in winter for shedding snow.

[@JCemusictv]

Great video. Straight to the point and no fluff. Please continue your testing. Thank you for your efforts.

[@rkeantube]

yep and in a snow type weather back will still produce power from light reflected from snow and thus heat up the panel and help clear snow from top and in cold will even be more efficient

[@edwinungerer7989]

very cool

[@gregpochet4812]

I'll add to the Vertical Crowd. Would like to see the performance when they are mounted vertical. I hope you have that in your plans. Great video!

[@everydaysolar]

Thanks for the feedback and that does sound like a great next test. 👍

[@jaspergrosz9653]

There's a guy out there who already tested vertical panels with mirrors on the floor beside them to help cancel out the middle of the day dip in power generation.

[@robertlee6781]

Those brackets look pretty cool. Thank you for sharing the link.

[@ChrisDoesWhat]

Good information. We just got 2 that we are going to mount aft on our sailboat. Really hope the reflection off the water helps.

[@weegieboard8432]

i'm also looking to do so, can you update this comment when you have feedback? i'd imagine the white epoxy paint and water would both provide highly reflective surfaces which could be a game changer for boats specifically. uncertain though...

[@ChrisDoesWhat]

@weegieboard8432 we plan to show the hopefully benefits of the bifacial panels on our sailboat on our channel.. We were forced to change our 2 LG 375 watt panels after Hurricane Milton.

[@weegieboard8432]

@@ChrisDoesWhat im sorry to hear that, hopefully everything is safe and intact. i'll check your channel out, will you be putting the information out soon? sorry if that seems insensitive, just got a young family, moving onnto a boat and at a crucial phase of redesigning infrastructure and i cant find reliable info on it's application specifically on a boat all the best, al

[@ChrisDoesWhat]

@weegieboard8432 I hope to get that info out this week or the next. Right now, we're having a new solar arch built. Love this guy and the info he puts out, but like you, we saw no info for bifacial panels on a boat. We took the plunge and hope the results are worth it.

[@ChrisDoesWhat]

@weegieboard8432 I wish you fare winds on your journey! We lept in a year ago, and we're still trying to get to the Caribbean.

[@Ulbre]

I love this ground mount system. Those brackets make it so simple. You'd be hard pressed doing it cheaper. The video you did on building that ground mount was excellent and it took next to no time. Tbh, If you have an area that gets good hours of sun then I can't see any reason why this couldn't be a permanent solution.

[@arthurhammeke8296]

Yes, if anything I did get out of this video is the no brainer solution to use fence posts and brackets. FYI, these fence posts are designed to prevent cattle from getting out, so should work well in this application.

[@kaf2303]

The high mount is so close to the high mount/ white rock that it is probably also being slightly effected by the white rocks.

[@matthewprather7386]

Affected too.. 🙂

[@cakekomo]

can you try the bifacials vertically? I've heard mounting them vertically N/S where the morning/evening sun hits them is the best mounting. Would like your testing on it if you could!

[@dnlmachine4287]

Snow climates, if you have only a fixed angle option, set it at or near the winter angle. In mid latitude Canada, the winter sun angle is nearly flat. Something like 9 degrees from vertical. In summer, the panels will be saturated anyway. Snow shedding and better winter capture are seriously worth it. Vertical mount on a wall or fence is a great option if racks are not possible. Snow, especially wind drifted snow, is terribly obstructive once it settles on the panels and there is cloudy winter skies. Stay gold.

[@johnzach2057]

Very interesting! So this can really help in the winter.

[@everydaysolar]

Yeah, should give a nice bump!

[@danielmcardle3476]

the patch of rock was a nice idea, but surely it's a bit small to allow reflections over a wide range of angles for the incident light?

[@RobertHopkinsArt]

Thanks for doing this valuable comparison! When I put my bifacials on my shed, like you, I plan on painting the shingles white. No, there won't be the distance to help out reflecting the light, but every little bit helps. Plus, my shed shingles should last another thirty years!

[@richardhobbs7107]

will also keep the shed interior cooler.

[@RobertHopkinsArt]

You absolutely correct, Richard!

[@danielnicholls6868]

move your mounting 2x4 to the sides of panels and move your reflectors more out front of panels plus a white wall back 8ft for the max output👍👍 plus you can keep bifacials 5 to 10 degrees more vertical for better snow slide and reflection in winter👍👍

[@Dirt-Diggler]

Isn't the rear panel being shaded by the 2x4 running in front of the cells ?

[@FlowFabe]

Definitely will affect the results significantly

[@Senthiuz]

Not as much as you might think. I found a paper on it where they tested a 25cm wide board at various distances. When right up against the cells, it had a significant effect, but pulling the object back a little cut that loss quickly, also painting the board a reflective color also reduced the loss significantly. "To conclude, the measured, large variation in rear irradiance per cell due to real outdoor conditions does not lead to increased risk of hot spots as the current mismatch is too low to cause solar cells to get under reverse bias. Furthermore, the power loss is as small, -2%, as the small reduction in irradiance at about 10% rear irradiance. By replicating these effects indoors at about 17% rear irradiance, it is shown that with decreasing distance the observed drop in current due to indirect light shading increases. For thin objects close to the module, no current drop is observed for cells not directly behind the object, but a small reduction is observed when the object is 10-20 cm from the module. The drop in current is in good quantitative agreement with the measured reductions in rear side irradiance. Finally, we have shown that increasing the reflectance of the near-field object, strongly reduces the drop in current."

[@Meh-2023]

Makes sense. Look at the depth of the shadow cast by the low mount.

[@SergeantSolar]

I think I was the first to think of the tpost idea. I'm was building a home and needed something portable, weather resistant, and cheap. Great video tho bro

[@UserName-q4i5d]

There's something called an 'uplift force' and if you don't have wind-deflectors behind the panels they will be pushed by the wind like a sail.

[@diytwoincollege7079]

We all learn something every day.

[@everydaysolar]

Amen.

[@kszysiu94]

I can see that when people are testing bifacial panels are forgeting about one important factor - shading the backside of panel. bifacials should be mounted the way that there wont be any beams under the panel. They are effectively shading backside of panel which is stealing most of eventual backside earnings. they should be mounted from sides, so there is nothing directly under panel.

[@scottstormcarter9603]

nice experiment

[@bloepje]

I am especially interested in your T-pole setup. Never seen anything like it. What are the wind gusts that you experience in your environment?

[@everydaysolar]

We usually see 1 day of 60-70 mph gusts per year. If I wanted this to last for years I would add posts on each side of the panel and probably some type of cross bracing left to right and front to back.

[@Richard-nb4iv]

Great video! I wonder what the difference would be if the panels could be mounted with no obstructions on the face as well as the face, Kind of like a picture frame .Your giving me ideas! I could make an awning out of bifacial panels over my south facing double white garage doors. Possible 17 feet plus or minus. 😅

[@BrianJense]

The stones provide more benefit if they cover a larger area than just below the panels. For anyone doing this in a real installation going a full panels worth to either side and behind your panels will give you a % or 2 more power.

[@Hansen710]

you would also have to clean the stones to keep them reflective, in many places.. personaly i would go for a flat surface that ca be cleaned without hurting the panels.. it is posible to get white tiles for example or paint concrete (with paint you can also add the perfect white and finish that makes it more reflective) im not going to presure wash those stones right under a panel and im deffently not hand cleaning them 🤣

[@boxster1970]

Thanks Scott - great info. I'm planning a small solar system for my camper van using 100 watt panels. Your videos have been very informative. I noticed that several of the 100 watt vendors are now offering bifacial versions. Wondering how much benefit you would get from a bifacial 100 watt panel on a silver van roof?

[@bobswanson8464]

I think the "High Mount w White Rocks" benefited more from the "Off White" Garage more then the "White Rocks". Lots of light will be reflected off the Door and Cement.

[@freddurstedgebono6029]

Love this cuz I was looking at the Trina 415 watt or 425 watt for 20 bucks more per panel

[@SALiving101]

If you put a plastic mulching that use in farm for the ground of bifacial panels it is more effecient because of the reflection from its silver ground facing to the bifacial PV.

[@obinnaelviso]

Can you try using a more reflective surface than just a plain white cloth. Something that reflects like a mirror

[@Hansen710]

if you take a sufficiently white surface it will reflect 100 % light but if you compare it with a household mirror that reflects only 80% a cloth is probetly just as good as a mirror

[@casemodder89]

​@@Hansen710thats the biggest BS i heard in a long time... headlights would have a cloth hanging around the bulb instead of a chromed reflector.... 🤦‍♀️🤦‍♀️🤦‍♀️ some people are just not the brightest candle...

[@obinnaelviso]

@@Hansen710 Why don't you do an experiment with your phone torch. Flash the light to a mirror and to a white cloth and see what reflects more

[@frankthies221]

One of the issues with a mirror is the fact that the light bounces off the mirror at a specific angle. That means you need to aim your mirrors, not easy with the sun moving across the sky. Bi-facial panels harvest more energy on overcast days than mono-facial panels because the light is diffused and coming from the entire sky. White stone is a good choice when you look at the cost/benefit of something more complex and expensive.

[@QB2ERS]

Mirrored is better but more difficult to keep at the correct angle thru the day.

[@darknetworld]

Well you did the solar power panel stand straight up? study found it reduce heat. Did found some video on testing. Meaning not on angle 45 but standing like the pole. There are people testing about it in the field.

[@everydaysolar]

That is worth a test, seems like that would take a lot of abuse in the wind.

[@jeffheiner]

Thank you!

[@efx245precor3]

Try the vertical mounting

[@davidbruce3632]

I'm thinking that closer to the white building has an effect on the white rocks panel as well.

[@velianlodestone1249]

do you reckon that you're peaking at roughly the same levels on the sunny days because the high mount panels is getting hotter?

[@Teslavangelist]

What is the bracket holding the 2x4 on the field fence post?

[@Teslavangelist]

Oh, it's linked. Nm!

[@jcadult101]

Should hang something between the panels, the rocks will reflect some additional light onto the other panel as well, skewing your results.

[@grounded7362]

I am wondering how much loss/gain, you might have between two bifacial mounted high but with one laying flat or near flat might be.

[@swpatech69]

You should try this with a white panel a foot or so behind the solar panels. I would think that you should be able to double those gains.

[@lv_m7026]

It's interesting if set up of white surface at the same angle as solar panel will increase efficiency?

[@everydaysolar]

I showed some improvement 👍 You can see the numbers at the end of the video. I would say it is worth the add.

[@QB2ERS]

I think u are correct

[@Hansen710]

9%-12% up in reflection is not bad, when the back of the panel only produces 1/5 of what the panel is capable of

[@QB2ERS]

Sunlight directed on the front of the panel is 20% of the direct son value i read. So the rear is the same then? Interesting

[@janmessek1826]

Those wattmeter look like ones I tried and found to be very inaccurate for measuring watthours.

[@plinble]

Depending on your rock, it might not stay white forever. I've had some limestone around the house for over 25 years, and it's now more of a grey. Also changes colour when wet, but it is a natural weed surpressant which is nice. White granite might be good, but there are other considerations like lawnmower blade damage. Limestone shouldn't damage mild steel as much.

[@davidorcutt9246]

Awesome! Now low mount with white background :-)

I would like to see what a bi-facial would do standing on edge with white on either side.. If the main face is pointing south southeast where the sun goes over the top edge and the white surface lights up both sides the panel might do even better..

[@MyWasteOfTime]

In my county we can't ground mount panels higher than 6' off the ground :(

[@everydaysolar]

Really? That is a county-wide code?

[@imacmacnerd]

A good use of T-Post. I wonder what the weight limit could be?

[@everydaysolar]

I would just add T-posts between each panel and string them out as far as you want.

[@UserName-q4i5d]

Aluminium has like 90% reflectivity, here's an idea: get some video screen paint (reflective silver) or a movie theater screen fabric, put it under the panel so that it covers 2x the area of the panel, see what the result is then.

[@scottbinder6656]

Just my observation... but, because of the proximity of the two HIGH MOUNTED arrays to each other, the array WITHOUT the white rock would have received some benefit from the white rocks. It would (again, my opinion) have been better if you had made sure that those two arrays were more isolated from each other.

[@ngk330]

Can I use those meters on panels that aren't hooked up to anything?

[@casemodder89]

sure. as long as the open circuit voltage does not exceed the 100V. but you will just measure the OCV without any load. you need a load (mppt charger) to A: drag the voltage down to the usable one and B: produce some actual yield. how else would you compare setups ?

[@rnkustomz]

@@casemodder89I literally just want to compare 3 panels for how many watt hours they would pull in the same day, I don’t have enough power stations to plug all 3 in

[@casemodder89]

@@rnkustomz like i said, you need a load to draw actual current from the panel. otherwise it was like running a car in idle for 5h and then telling it consumed 4 liters of fuel. but that 4L is not what is consumed while doing some actual work. and without 3 identical loads you could never compare anything. doing 3 different days screws the results just like different loads would.

[@rnkustomz]

@@casemodder89 dang okay. Thanks for the help

[@terrylfluckiger9113]

@@rnkustomz Replying late, but hopefully better than never. You could connect one meter to each of your 3 panels, and then parallel all 3 panels together and connect them to the same load. You would need at least one load, and like @rnkustomz said, it should be something with an mppt charger. One power station should be good enough, if it can take the full input of all 3 panels. You may also need to draw power from it during the test so it isn't full. I have a couple of those meters, they are fairly cheap and do work well. Check them with a multi-meter first, mine tend to measure the current differently than my meter, so they are not very accurate in low light conditions.

[@rockys7726]

What about low mounting on a reflective roof with galvanized metal?

[@ColoradoTodd]

I thought the idea with bifacial panels was to mount them vertically, facing east/west

[@guillermomaguire5394]

The cloudy day results seem off. Any thoughts on why the big difference?

[@velianlodestone1249]

The temperature of the panels on a cloudy day are going to be substantially lower (minor reason), major reason: the sunny side produces a whole lot less on a cloudy day, whereas the back side is going to produce roughly the same as on a sunny day (shadow side vs. shadow side, the back does not care about sun and is still producing 6-8% of the sunny side. On the overcast day that 6-8% rises a lot relatively because the sunny side produces less.

[@guillermomaguire5394]

@@velianlodestone1249 okay, thanks for the reply

[@thedindon]

Sorry I have a non-related question: I bought a River 2 Pro and I’m having difficulty choosing a wire brand to connect to my solar panels (2x 100W). Do you recommend any specific brand?

[@dyslectische]

Ans if you set some alluminium foil on the ground or roof ? Or a mirror?

[@cybernoid001]

people have done that and it does increase output, but you also run the risk of the panel overheating.

[@american7169]

Arent bifacials supposed to be mounted at 90 degrees for best output?

[@everydaysolar]

That is kind of a recent trend, I am concerned about wind but I think a test is in order 🤔

[@juustjoshin]

Curious about bifacial along a fence - I know it’s not as efficient as raised or angled but realistically it’s the only possibility in my yard. Do you think an average suburban home with a fence could power their needs in this scenario?

[@QB2ERS]

Checkout solar balcony fencing - it works.

[@QB2ERS]

@@juustjoshin a solar panel balcony "safety fence" with white painted building behind, perhaps 2 or 3 mtrs does work, but i don't have data.

[@philippserrin8268]

If the question starts out as “Do you get more electricity by raising the panels off the ground and putting reflective material underneath”; and the answer is clearly Yes; the new question should be is it more cheaper to get this extra production by spending extra money on more expensive mounting and white rock -- or simply buying one or two or three more panels ? I am thinking that the later is probably going to give you more bang for the buck.

[@MasterChief4U]

I never seen someone talk some much. How about show results for each setup..

[@bobnomura2068]

You didn't try vertical mounting. For best results I think they should be completely vertical, oriented north-south, and surrounded by white rock. Morning to mid-day, sunshine on one side, and vice-versa for the afternoon. Otherwise, not worth it to get bifacial panels.

[@talpolano4549]

Try east to west then north to south :)

[@fabulousoffroaddesigns5080]

More gravel would have gotten you more gain. A white fence 41 inches behind the system would have doubled that gain.

[@Tryp-j9d]

He’s NEVER in the SUN for the ENTIRE VIDEO!!!!

[@everydaysolar]

For this testingI limited the data Collection for 9:30 am - 1:30 pm each day to ensure each of the 3 panels had full sun during the test.

[@Tryp-j9d]

@@everydaysolar 9:30am to 1:30pm…WHEN IT’s SUNNY!!!!!!

[@ChristmasEve777]

"Classic" DIY is leaning a solar panel on the ground or against something? Do people really do that? I've been a solar enthusiast for four decades and I find that surprising. I would think a wooden ground mount or wood/Unistruct would be a classic DIY setup. I only lean them against something when testing a panel.

[@jimthvac100]

You are messing up your test by having those 2x4's going across the back of those panels like you have it. When you have bifacial panels you have to treat the bottom of the panels the same as the top and not have anything shadow reflected light to the bottom of the panel. You would not run a 2x4 across the top of your solar panel would you? well you don't want to do it to the bottom either. What ever cell is covered up underneath and has the least light no other cell will be able to pass any more current than that cell same as on top. You get the most of bifacial panels when you have panel supports that are thinner and only attach to the the edges of the panel NOT like you have it. You are not the only one that have made this mistake. I am sure this is why you are getting so little extra current from panels being up high vs laying on the ground.

[@davefroman4700]

I do not understand why American's are so worried about their "Return on Investment" these days. The point is it WILL pay for itself LONG before you need to replace it. And when you do want to replace it? It will be far cheaper than it is already today.

[@avypath]

a lot of people are motivated to do solar to save money. you have to weigh continuing to pay $100/month forever vs paying $40k right now and paying nothing for electricity in 400 months. the less you pay upfront, the quicker you get to actually being better off

[@davefroman4700]

@@avypath You can get solar for a LOT less than $40k today. The nice thing about solar? Is its modular. You can add to it as you go. And you do not need to be a rocket scientist or a structural engineer to do it. I started with a small 3600w worth of solar, but a inverter big enough to handle all my loads. Working with the DC side of things is easy. As is building your own ground mounts. I've added 24kw worth of solar to my system, after they left. And where I live? There is no net metering. They will not pay for any power I export, so I did everything off-grid. The added incentive was they wanted $22k just to pull wire less than 3/4 of a mile into my property to start with.

[@SarahStuff-p5u]

High panel with rock is by garage, just saying.

[@MrX-f5f]

Biracial is supposed to be vertical not at 45 and south facing

[@thefooshisloose]

That is a myth bro, unless you are doing something super niche and not trying to get the maximum out of your array LOL. This has been beaten to death and always proven to be wrong. Good try though.

[@priestesslucy]

Autocorrect did you dirty 😂

[@YouLookinAtMe-Bro]

​@@priestesslucy I've seen that same mistake several times.😅

[@Hansen710]

then you would need bifacial that produces the same on the front as on the back its simple math, how will you get the same from both sides when a normal 400w bifacial only produces 100w on the backside the chap bifacial that does not produce the same on both sides goes south for best production, simple math and not vertical, they have to face in the most direct angle to the sun. if you want sun to reflect on the backside, you have to make sure you are not blocking it all. for example with gaps between the panels yes you can switch the direction on the panels, (1 west 1 east 1 west and so on) but that still doesent make them do best in a verical position facing east west

[@Hansen710]

@@thefooshisloose then explain how the dutch university study got more out of placing the panels in vertical east west ??? because youtubers think all cheap bifacial panels can do the same as expensive, it does not mean it is beaten to death ofcourse they get bad reasulat when they all are using 400w panels that produces 100w on the backside they are not even going for the 550w that produces 200w on the backside youtube science is not allways real science