This panel can put out close to 100 watts kzfaq.infoUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg 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 love your contact, no shouting no melodrama just quiet information.

Amazing the flat mounted ones even outperform the angled ones

Me and my husband just got a class c he wanted solar but I didn’t want holes in my roof. I just saw your other video of how you installed yours and now I’ve been bing watching you to see how they were doing and down loaded your guide. You won me over with your setup and knowledge. New subscriber thank you for your help and videos

So happy to here this!! LOL We just finished our solar install yesterday following your set up. Your directions and mounting materials worked perfectly. We have an Outdoors RV which came with 170 watt panel on the roof. We already have a Zamp 200 Watt suitcase and just added the two 175 Watt Flexible Renogy solar panels for a total of 720 Watts. Plus we bought two Battle Born Batteries. We are set! Thank-you for all of your videos.

Really appreciate all your videos, you break it down simply, easy to follow and many things I have been able to use. Keep it going please

“Everyone loves Tito” should be the name of your channel❤ great videos!!!

Thanks Brian, glad you did another video on solar output.

Pretty interesting, Brian. I thought for sure the temp on the roof would be much higher. Looks like the insulation you put under the panels are doing a great job. Thanks for the review!

Coming up on that 100K mark. Only 7.5K togo! Good job

I noticed your shadow when you were near the ground panels. Were they not pointed at the sun to approximate the roof panels? My ground panel gets too hot to touch in full sun. I made a very basic Sun Dial (got the idea from the Mars Rovers), that I mounted to the corner of the panel. It really helps in aiming the ground panel directly at the sun and even ahead of the suns travel. Thanks for the video. I appreciate your work.

Impressive results really, i’ve got my flexible panels mounted very similar to yours and they see performing really well too. Considering my roof is black and aluminum the ventilation really makes a big difference. Thanks again!

This was very helpful to me. Correct me if I am wrong, but you do have some differences: You have 70 cells on the ground and 72 on the roof, and the cells on the ground were tilted. The roof should have delivered 36/35 more volts than the ground at the same temp. The roof was hotter so it would deliver less. It was hard to tell the difference. However, if the two sets were at a different angle to the sun, that would add another difference. At 1, I would figure the ones on the roof had the advantage. The real benefit to me is seeing that the MPPT was putting the voltage at 35, so when I use a 60 cell panel, my Vmp will be around 29.1. I have an 8 cell LiFePo4 pack, and thus my voltage will be 26.5-28. So, without a charge controller I will have 3-4 spare cells out of the 60. That seems like a good margin for potentially higher temps and a few years of degradation. If you could pull up one of the roof panels and get us a temp measurement off that roof the moment you lift it, that would tell us whether heat is being transferred to the roof. Or maybe you can put the ground ones on a piece of plywood or something and measure that. My understanding from someone else is that the heat is generally not going through the back like a typical fixed panel.

Thoughtful presentation Brian. I have often wondered whether the lack of ventilation impacted performance; obviously your test shows no, as production & temperature variables were negligible. One needs to also consider the longevity of the array, but that is a different issue. BTW, I love SunPower panels & components as we installed on 2 of our prior homes and now embarking on installs a new system on our née home. As always, well done my friend.

I mounted these guys on aluminum plates with holes, and additionally are able to set up in different angles with supports towards the sun, when my RV is sitting still. So they are perfectly cooled from the back, the aluminum helps a lot with dissipating the heat from the sun.

Brian, thank's for the video. I'd believe that the copper sheet underneath the cells helps provide a better heat sink distribution for longer lifetime, however, power degradation will happen when the panel heats up.

👋 Thanksagain, Tito. I'm LOVING my new Tito Shades !! You're a genius. 🌞 Enjoy Sedona.

athe reason the ones on the roof are putting out more power is less loss in the wires if remember correctly you used larger wire and the shortest run you could do so both combat line losses while your ground array has smaller wire and a longer run of wire hince lowwer performance from line losses in the ground array.

The ones on the roof still have a little ventilation with the corrugated plastic you used to back them. Also with them at a slight angle on the sloped roof allows a little bit of chimney affect to allow that air not to stagnate completely.

Hi Tito, when using a I-R thermometer, better use your own shadow for blocking sun radiation. The sun’s I-R that wil be reflected by the panel will influence the reading of your instrument. Always measure in a 90 degrees angle to the surface on the exact same spots on all panels will give reliable results.

Thank you Tito, I've stumbled across some of your videos when I'm looking to improve either my Yacht or Class, A and I find them very instructive. And thank you so much for your free book, I'm about to go solar on my Yacht and I have so many question right now, your book will answer some of them I'm sure. My main concern today is the durability and quality of these flexible panels. But on my boat this would be the easier and cheapest option. I already have rigid panel on my RV but they were already installed when I bought it and I have the felling that the power they deliver is not what it's supposed to be.

Brian, thank you! Very informative & exciting to see this latest video!

SUNPOWER for the WiN ! Love those panels. Peacefrom510

I appreciate your approach to the issue of how heat buildup affects solar panel power output, but you need to control for a couple more important variables. First is.the sun angle. Your roof-mounted panels almost certainly were receiving a different amount of sunlight than the ones that were set up on the ground. The intensity of direct beam sunlight (as opposed to diffuse skylight scattered by the atmosphere) is at its maximum when it is directly above the panel. As the sun moves across the sky, the direct beam portion that comprises the vast majority of solar radiation decreases in proportion to the sine of the angle of the sun relative to the surface (in this case, the solar panel). So, the maximum solar power can be achieved when the sun is directly over the panel (sun angle of 90 degrees). It decreases to 0.707 of the max when the sun angle is 45 degrees above the panel, and to 0.5 when the sun angle is 30 degrees above the panel. To do an apples to apples comparison of flush-mounted vs. free-standing panels, orient the free-standing ones horizontally like the ones on the roof of your RV, and ensure that the ground beneath them is shaded. Also, if you want to account for the effect of heat on panel performance, it would be good to see some significant heat differences between the panels. And if your assertion is that there isn't any heat difference between the freestanding and roof-mounted panels, then I'd suggest that you take multiple temperature measurements of the free-standing and roof-mounted panels over the course of a cloud-free day and report the results. Anyway, I love your presentation style and the equipment you used to generate the data you reported. Thanks.

I read somewhere that an RV owner in the Phoenix area had flexible mounted panels on his RV roof. The panels died after about one summer outside in Az's valley heat. I read this shortly after my brother had also installed 2x 200w flexible panels on the roof of his travel trailer. Now, he stores his RV outside in the sun when not in use. They did not make it through the summer either before both died. We think the flexible panel overheats without airflow underneath, but you may not experience this overheating if the ambient air temp is under 100F. Az's summers are brutal where midday summer heat can reach over 120F.

Thanks Brian, I enjoy all you videos. My thought is the ground panels are dissipating the heat faster than roof mounted panels. The roof panels with the insulation backing are holding the heat. I also would be interested in the heat transfer through the roof, into the RV. What is the temp of the roof membrane? Having framed panels mounted above the roof I would think shade those sections of the roof, reducing the heat transfer into the RV. Thanks again for your information and teaching!

The roof panels performed better regardless of temperature, because they are closer to the sun. Thats my theory. 😊

Great video. Answered most of my questions. Thanks!

I would assume with the roof being white and pretty much reflecting light that's the reason why you're getting more wattage from the top ones. It's just a thought I might be wrong

thank you for checking temperature and info 😊👍👍👍👍 Have a nice day

Nice video as usual Brian, I would like to see the temp of a section of roof with no solar panels and test the same sections in the interior.

the ones on the roof are laying flat and the ground ones are angled, so depending on the time of day/sun position the more direct towards the sun should be hotter

Good video, Brian and I would have thought the panels on top would have been hotter. I'm wondering though if there will be a difference in longevity. It would be interesting to see how they hold up over time compared to the ground-mounted ones.

Great test. That was interesting.

You have very good topic videos, many that i am interested in. I have found my flexible panels work very poorly when i attach them to my RV. I assumed it was the heat.

Voltage is affected much more by temperature than current. Current is dependent on irradiation. Because the charge controllers are MPPT type, and will track the IR curve, power is not really a good measurement of the differences. This is what a curve tracer is used for. I have one, however it is not a commonly available tool, as it costs about $4000. Irradiance, cell temp (measured on the back of the panel), azimuth and tilt angles are all factored into the calculations.

The question I have is: What is the temperature being transferred to the RV roof through the plastic spacer?

When the panels get into the 120+ temperature range, doesn't that damage the roof membrane since there is no airflow between the panel and the roof?

Thanks Brian. It would be interesting to see the temperature delta between the actual RV roof and the top of the roof panels. I’m in the process of installing a small solar panel to trickle charge my chassis battery while our RV is in storage for 3 months. The panel is 14”x14” with a hard plastic frame. I decided to mount the panel on painted 1/2” plywood with strips of coroplast between the panel and plywood so it can breath a bit better. I’m hoping a cooler panel will last longer but who really knows. LOL

they are at different angles to the sun

When you live in Arizona you have to accept that everything is hot 🔥 and will fail sometime lol sure you do your best to help but its a one side fight against the sun . But its still better than 300 days of dark and cold rain snow and mowing grass

The ground array is using longer, smaller gauge cable, and is not at the same angle to the midday sun. This would contribute to lower output.

Knowing water is very essential out in the desert especially while boondocking, but it would have been interesting to see how much the performance would increase if you ran some water over the panels

Heat of panel same but the transfer through yhe roof is radically different. Raised panels way better.

Thanks for them info brother. Im still hoping for a nice rig some day soon. Retirement is just around the corner. Thanks for them lift. Lol

It is my understanding that there is a high risk of damage to the fiberglass roof of RVs due to the heat of flexable panels in fact some RV manufacturers have stopped using them altogether and gone to hard mounted panels only. Unfortunately a new rig I am looking at purchasing only uses flexible panels so I may not move forward with the purchase for that reason even though I love the rig itself.

The panels on the roof are closer to the sun Tito!

Just thinking aloud here... maybe under those flex panels you can encourage more airflow by bonding them to a thickness of a boat mattress air underlayment ... and attaching that on the roof... it's a material with almost total air gap making it up... you'd get really high air movement under the thing and possible it would cool off more... someone with a 3d printer could probably make something up for you as well in tiles you could cut to size... then again the heat issues may concentrate in the outermost layer with the cells on it anyway and little improvement... there's stuff on amzn "boat mattress underlay"

you need a 2x ND filter for those full lit shots... :)

Interesting stuff!

The angle on the ground and the way you use the IR temperature meter, makes the measurement incorrect. measure under 45 degrees and block the sun with your own shadow and both set-ups needs the same angle. So it is an interesting test, but you should do it again with the correct set-up 🙂

Was there a difference in the wire lengths from the panels to the charge controllers? My guess the ground mount has more length. Also the input impedance of the two different controllers could make a difference too.

I used the exact same setup as you for mounting the flex panels to the roof and I do have issues. My panel is a Rich Solar 100W panel and it worked great for a while but after 8-9 months the top ETFE layer flaked off completely. It was possible to wash off the residue and I got some power back but now it seems like the panel overheats and I lose power.

I think that “ventilation” is somewhat a misnomer. Underneath of a traditional rigid solar panel is white and roof itself is white and when you mount panels on the roof using brackets... unless its blowing breeze, there “in theory” should be very minimal heat dissipation. This means that underneath of solar panels is probably used as a cooling mechanism because its always in shade so maybe it generates somewhat a cooling bubble, keeping operating panels cool enough to perform. Panels are usually black squares or black sheet which implies they always will get hot in the sun. I have had them so hot in florida sun that when I would wash the panels with a spray bottle, it would evaporate the water before I even had a chance to wipe them, which is why at home I just drag the hose in there at shower everything as I go. Of course that makes roof slippery so it is not a safe thing to do. In my opinion main reason why I want my panels raised is to remove any and all debris trapped under panels like acorns, leaves and such. That is about the only reason that I want them raised. I have never mounted them flush but in the past in one of my other RV’s I had them mounted much lower and have not noticed any difference between then and now. I do not use flexible panels though. I watched “I’m not lost I’m rving” back before they even set sail for the west and they engineered this crazy system and eternabond stuck every panel to the roof. By time they got from central florida to the keys for their first venture into work camping... just about every panel failed. At the time I was in between RVs and was looking to lighten the load on the roof until I saw their issues. I just have never recovered from many people having issues with flexible panels so I stayed with renogy monocrystaline. Mine sit about 3-4 inches off the roof and I have no intent of tilting them but all my mounts are such that when I drive, head wind basically blows everything clean under there, keeping roof tidy and not covered in green algae and stuff.

I did like you with cardboard under. Had 2 fail without.

You must have done this before you switched to the 170 watt panels. I wonder if the new fastening system will be cooler.

Beyond not having anything on the back, the movable panels can be aimed toward the sun through the day to maximize power, don't have to tilt the RV different directions all the time.

Any chance you can do a test with bougerv CIGS directly on the roof with a meat thermometer probe between the CIGS and the roof?

Good information

Great stuff.

my experience with small solar panel set ups it that the angle to the sun makes a real difference. your roof panels seem to be oriented more perpendicular to the sun than the ground set up i have found with my rich solar 100w panels that even a small angle will show different outputs. but then in the real world clouds have more of an effect than anything so my answer was to get two more panels.....ha ha ha.

It's not insulation you're putting under the panels. In fact, it's the complete opposite, and for good reason. The layer you're putting under the flexible solar modules is actually a thermally conductive layer. Its purpose is not to insulate, but to actually increase thermal conductivity between the module and the roof of your RV so that your panel can more effectively transfer heat to the roof of your RV in order to stay relatively cool. Also, out of curiosity, why did you connect your panels in series?

I should have gone back a few comments.....ago.

You might not want to hear this...but I am being honest. I had 6 different flex panels ( Slow Learner). After you leave them out in the sun ( DUH ) they become VERY BRITTLE. That means if you pick them up without first saying a lengthy prayer, the panels will crack. When theY crack the infinitesimal ribbons inside of the panels will crease to conduct electricity. And you now have an expensive piece of fiberglass to draw pictures on. The first ones I bought were TWO HUNDRED DOLLARS apiece. Get the salt and pepper ready.

I have two traditional 200 watt glass panels on my Class A, but given the extra weight compared with flexible panels, considering using flex panels going forward. I only wish they came in 200w configuration.

Hi Tito, very good videos you do, my compliments! One question; in another Video you mounted glass panels, out off your long experience what would you suggest to mount, flexible or glass panels? Lot’s of people say with the newest EPFE and new cells like Renogy or so it makes no difference anymore, What do you think?

Would love to know what the roof temperature was on same day and what the temperature on the back side of the panel was?

There will also be wire loss if your wires aren't the same length. At lower voltages this can make a huge difference in net output.

Interesting

I have no idea where to start I have one solar panel on top of my trailer I know it's going to to the batteries that are here at Scott some yellow device that I think it's regulating that power into the batteries but again I have nowhere that I know please direct message me I really need some help on what to do I am very limited on money and I'd like to be able to be more off-grid and be able to keep my refrigerator going and the power going without being plugged into Shore power

why not flat mount the air gapped panels as well. doesnt the angle affect the results as well?

I may have missed it, did you insulate the panels on your roof? I have a 24’ LTV that came with 4-100-watt, Go Power, flat panels. After 3 years they were delaminated, & very hazy, never saw anything close to 400 watts production from them! Late last year replaced with 8-framed panels. Hoping that they will help to shade roof, keeping inside a bit cooler. I think that for your temp comparisons to be accurate both sets need to be completely same flat positions!

Hello interesting to see how hot the panels are. but I wonder how much energy the panel delivers when the measurement is performed. affects the temperature a lot why flex panels poor durability and expensive

What about the temperature on your white roof section? Are you adding to the heat inside the rig by having flexible solar panels mounted on your roof?

I have two questions: how do you store the flexible solar you had deployed on the ground? I was going to do that, but opted not to because it seemed to me the flexible panels would break too easily if moved all the time. Please do a video on that some time! Next: your antenna mast, I assume that is for WiFi, are you running omnidirectional or yogi? How far are you from the cell tower, what type of signal are you getting from your phone verse WiFi?

Different angles ??????

different angles different solar input that's all I have to say

The panels on the roof are nearer the sun... :D

You might be getting reflect off the roof onto the panels. Get a sheet of stainless and reflect light onto your panel. Then the output should go up.

This is somewhat related to this post. We want to do a lot of dispersed camping this year with our 28' Class C. We can't find where dispersed camping is legal on state or federal land. We've checked with the forest service in Colorado where we want to camp. BLM, Barnes and Noble. Nowhere can we find these maps. I remember years ago seeing maps with little circles that marked where boondocking was allowed. Do you know how to find these maps ?

@rvwithtitodiy hey there, i have a 160w flexible panel on my van and recently my voltage has dropped to about 8.6-8.7 volts.. (unuseable..) . I tried swapping diodes but no fix.. any ideas what the issue is? Is it toast?

Your performance increase is likely due to the increased irradiance due to the reflective white roof. This will create more current and therefore offset the reduction in voltage due to the higher temperatures. Full disclosure...I used to be a technical trainer for SunPower.

A number of comments had possible reasons for the differences. I wonder if the white roof reflection, compared to the darker environment for the ground panels makes any difference. Just a thought.

Great review. I wonder how much heat is getting through the polycarbonate board?? As you recall we installed ours the same way on the roof and they are still holding up!

Hi m8 what were the measurements of the t track you used plz ?

Thanks.

I have a high top van and the roof is far from flat so I will be limited to two panels up there; the highest output I can afford. By connecting in series will I get more power to use to charge my batteries?

Brian - why did you set up your panels in a series creating 24v instead of parallel w 12 v to your controller - with the 24 v input to the controller wheres the conversion back to 12v to the battery -or did i miss something again

I think pannels on roof are totally horizontal so collect more Electric at mid of day

Isn't that RV roof made of aluminum? If so why not use it as a heat radiator?

The bigger question is hot hot is the ceiling on the inside of the camper under the panels. I am going to guess 20-30 degrees hotter Then comparing the old beat up panels on the ground????? You can't draw any conclusion from this mess

Brian, I’m going to do a setup similar to yours. Two 110 watt panels in series and a movable two 50 watt panels in series, connected in parallel to the 110 watt setup and then into a Victron 100 V, 30 A controller. Will this work? Does this system fully charge your lithium batteries? Thanks for your videos.

Any roof gets hot from the sun, even under a solar panel, from the conductive heat that travels through the entire roof. But if you were to add a layer of styrofoam under the coroplast, i think there would be even less heat transfer from underneath to the panel. Would you ever try that?🤔

It seems like the roof mounted surface panels would add a significant amount of heat to your coach. I am wondering how much difference it would make if you had ventilation on the roof panels, i.e. the one inch of separation or so? Wondering what the overall comfort factor is on the internal temperature of your coach may be?

Well its been two years how are the flexible panels holding up?

I'm going to be designing a new solar system for my new imagine 17MKE. I have two 100 watt flexible panels from my old system. Knowing what you know now, would you opt for flexible panels still or convert to glass if you had it to do over again? I'm leaning towards making my own glass suitcase to go along with my 200 watts of portable. Thoughts. I've watched all your videos as you have evolved through your mounting options and you have really helped a lot. Thank you

Tito, thanks for the videos. I’m a new RV'er and I really appreciate your advice. One question... what was the temperature of the RV roof next to the panels? Was the fiberglass much different than the panel?

I just finished removing my two 100w flex 'Sunpower' panel off my RV roof that were glued and screwed down directly to the roof. My two year old panels discolored the gel coat. I am replacing with mono crystalline rigid panels mounted to standoff brackets that will allow air flow under them. I wonder how bad the damage to the roof would have been if I left them on long term?

How about lifespan as compared to rigid panels mounted on the rv roof ?

Thanks Brian. Like 48