expiredwwglen posted Dec 24, 2024 08:55 PM
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Item 1 of 2
expiredwwglen posted Dec 24, 2024 08:55 PM
Massimo 300W Folding Solar Panels $99
$99
$134
26% offAmazon
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I found this deal while searching for a different solar panel. Looks like a good deal.
Reviews aren't the greatest, mainly people complaining about getting 70% of the rated output on the 100 watt unit.
https://www.amazon.com/Massimo-10...B09XGYQYPM
New Amazon Link:
Massimo 100W - 300W Solar Panels of Camping Outdoor Sports (300W) https://www.amazon.com/dp/B09XGYQYPM
Also available from Walmart for the same price.
https://www.walmart.com/ip/Massim.../978329269
New Walmart Link
https://www.walmart.com/ip/978329269
Edit:
Was sold by Costco about 2 years ago. $300
Here's a YouTube review where they got 291 watts.
https://youtu.be/vYp06kyA99k
New unboxing video from Yesterday where they paid $99
https://youtu.be/sTLENlePql8
Reviews aren't the greatest, mainly people complaining about getting 70% of the rated output on the 100 watt unit.
https://www.amazon.com/Massimo-10...B09XGYQYPM
New Amazon Link:
Massimo 100W - 300W Solar Panels of Camping Outdoor Sports (300W) https://www.amazon.com/dp/B09XGYQYPM
Also available from Walmart for the same price.
https://www.walmart.com/ip/Massim.../978329269
New Walmart Link
https://www.walmart.com/ip/978329269
Edit:
Was sold by Costco about 2 years ago. $300
Here's a YouTube review where they got 291 watts.
https://youtu.be/vYp06kyA99k
New unboxing video from Yesterday where they paid $99
https://youtu.be/sTLENlePql8
Product Info
Community Notes
About the Poster
Deal Details
Product Info
Community Notes
About the Poster
I found this deal while searching for a different solar panel. Looks like a good deal.
Reviews aren't the greatest, mainly people complaining about getting 70% of the rated output on the 100 watt unit.
https://www.amazon.com/Massimo-10...B09XGYQYPM
New Amazon Link:
Massimo 100W - 300W Solar Panels of Camping Outdoor Sports (300W) https://www.amazon.com/dp/B09XGYQYPM
Also available from Walmart for the same price.
https://www.walmart.com/ip/Massim.../978329269
New Walmart Link
https://www.walmart.com/ip/978329269
Edit:
Was sold by Costco about 2 years ago. $300
Here's a YouTube review where they got 291 watts.
https://youtu.be/vYp06kyA99k
New unboxing video from Yesterday where they paid $99
https://youtu.be/sTLENlePql8
Reviews aren't the greatest, mainly people complaining about getting 70% of the rated output on the 100 watt unit.
https://www.amazon.com/Massimo-10...B09XGYQYPM
New Amazon Link:
Massimo 100W - 300W Solar Panels of Camping Outdoor Sports (300W) https://www.amazon.com/dp/B09XGYQYPM
Also available from Walmart for the same price.
https://www.walmart.com/ip/Massim.../978329269
New Walmart Link
https://www.walmart.com/ip/978329269
Edit:
Was sold by Costco about 2 years ago. $300
Here's a YouTube review where they got 291 watts.
https://youtu.be/vYp06kyA99k
New unboxing video from Yesterday where they paid $99
https://youtu.be/sTLENlePql8
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With the panel completely unfolded flat (i.e. not angled using the legs) at about 1pm CST (so sun past the meridian) I measured 32V on the XT60 output. Same voltage on the barrel connector. So I'm really not sure how Massimo gets away with claiming "~24" Voc (on their web site) for these.
I was able to find a discussion on an ecoflow Facebook group with a similar situation (although their portable battery had an even lower 25V max voltage on the MPPT input). https://www.facebook.co
There wasn't much in the way of conclusions there other than that these panels are quite a bit higher than 24V Voc.
The only other factor I'm not sure about (again, brand new to solar) is that apparently Voc increases as temperature decreases. It's in the mid 20s F outside right now. Apparently, manufacturers quote Voc in "ideal" conditions, which is probably 70-80 deg F. So maybe that could account for why the voltage I'm seeing is so much higher than stated?
I did take the gamble and try connecting my EB3A. It stayed at 0W (due to overvoltage) unless I left only two of the panels exposed and partially shaded them. That likely got the voltage down to around 28V. I was getting about 40W that way after I unshaded the two panels. I found I could then expose the 3rd panel and the charging rate would go up to about 70W, and then finally the 4th and 5th panels at which point I got about 135W. I then tried slightly angling the panels more towards the sun. I saw it go to 170W and then back 0 with the overvoltage message at which point I unplugged it. Nothing fried though, as I was able to fold it back up to only partially expose two panels. Then I plugged it back in and it started charging again at about 40W.
My EB3A was also already at 93% SOC, so it's possible the charging rate was being limited because the battery was almost at capacity. I need to run it down to 50% or so and then I can do some more testing.
But either way, I'm annoyed that Massimo lists these as ~24V Voc when they exceed that by over 30% (or that tilde is doing a LOT of work). Is this common in the solar panel industry? Kind of hard to believe that these were sold at Costco, although maybe this issue is why they're being dumped for $100 now.
These panels certainly aren't useless (although I'm concerned about the controller melting as it did for the previous poster), but I'm not sure it's worth keeping them. I don't really want to run out and buy a new (and undoubtedly more expensive) battery just to get an MPPT that can accept 33V. I read on reddit someone adding a buck converter to reduce the voltage, but that seems pretty hacky since the input voltage will vary with clouds and as the sun gets lower to the horizon.
Solar panels for 24V systems need to be about 34-35V for LiFePO4 and 31+ for Lead Acid.
It is still a shame that their web page is so messed up on these panels.
1. I discharged the battery to 0% last night and started solar charging from there (yesterday the battery was already at 92% before I started)
2. I turned on the AC inverter and added a small load (a power tool battery charger with a partially drained battery attached. Draw is ~18W).
I started off slowly like I did yesterday, with only two of the panels exposed (and laying completely horizontal). After a while I completely opened up all 5 panels, again laying flat and was getting about 125W consistently, with no over voltage message on the Bluetti app.
After 30 minutes or so I decided to prop up the panel to better face the sun. At first I just did it with my hands so I could lay it flat again if the voltage got too high. But sure enough I watched the wattage creep up to 199W and stay there.
So I just propped them up in the angled position and will leave them there until the sun disappears behind the house--probably in an hour or so. But so far so good and the EB3A's battery is up to 45% now.
It's also slightly warmer outside today--about at the freezing mark, so I guess that's another thing helping (if only slightly) to keep the voltage down.
So it seems like the Massimo can work with the Bluetti EB3A, with maybe some caveats. I expect one of these days I'll get a beefier solar generator, which should have no issues with the Massimo's higher Voc.
I'll update if anything fries or melts in the interim
Edit (1:27pm CST): Power tool battery obviously charged to 100% because the EB3A is showing 0W AC load now. However it is continuing to take 199W from the solar panels. EB3A's battery is up to 63%!
Edit 2 (1:53pm CST): At 74-75% SOC, the EB3A went to 0W input and I saw the over voltage message in the app. I went out and disconnected it and looked around for a larger wattage load to attach to the inverter to see if I could get it to charge above 75%, but in that short amount of time the sun dropped low enough that even angled I can't get 199W out of the panels. By now I'm only getting about 30W even with them angled, so pretty much done for the day.
Tomorrow I will try again. I'll attach about a 50W load to the inverter and see if I can get the Massimo to continue charging the EB3A above 75%.
1. I discharged the battery to 0% last night and started solar charging from there (yesterday the battery was already at 92% before I started)
2. I turned on the AC inverter and added a small load (a power tool battery charger with a partially drained battery attached. Draw is ~18W).
I started off slowly like I did yesterday, with only two of the panels exposed (and laying completely horizontal). After a while I completely opened up all 5 panels, again laying flat and was getting about 125W consistently, with no over voltage message on the Bluetti app.
After 30 minutes or so I decided to prop up the panel to better face the sun. At first I just did it with my hands so I could lay it flat again if the voltage got too high. But sure enough I watched the wattage creep up to 199W and stay there.
So I just propped them up in the angled position and will leave them there until the sun disappears behind the house--probably in an hour or so. But so far so good and the EB3A's battery is up to 45% now.
It's also slightly warmer outside today--about at the freezing mark, so I guess that's another thing helping (if only slightly) to keep the voltage down.
So it seems like the Massimo can work with the Bluetti EB3A, with maybe some caveats. I expect one of these days I'll get a beefier solar generator, which should have no issues with the Massimo's higher Voc.
I'll update if anything fries or melts in the interim
Edit (1:27pm CST): Power tool battery obviously charged to 100% because the EB3A is showing 0W AC load now. However it is continuing to take 199W from the solar panels. EB3A's battery is up to 63%!
Edit 2 (1:53pm CST): At 74-75% SOC, the EB3A went to 0W input and I saw the over voltage message in the app. I went out and disconnected it and looked around for a larger wattage load to attach to the inverter to see if I could get it to charge above 75%, but in that short amount of time the sun dropped low enough that even angled I can't get 199W out of the panels. By now I'm only getting about 30W even with them angled, so pretty much done for the day.
Tomorrow I will try again. I'll attach about a 50W load to the inverter and see if I can get the Massimo to continue charging the EB3A above 75%.
Sounds like you can make do, but not what you really want.
The one measurement I took showed lower temperature than my first one (It was colder out).
I was able to charge the EB3A up from 79% to 100%. Of course it didn't go all the way at 199W. The charge rate slowed down for the last 20% or so, but that is normal and desirable to help prolong the life of the battery cells.
Not sure what conditions that amazon reviewer had when testing the 300W with an EB3A, but it if was a warm day it's probable that the Voc was *just* low enough for it to work.
So, I guess I would conclude that if you have an EB3A (or many other solar generators that also have a 12-28V 200W MPPT) then the Massimo may be OK if you primarily plan to use it in higher ambient temperatures. Still, you may have to "massage" it by only exposing 1-2 panels, allow charging to begin, and then fully unfold and tilt as needed. If you need to use it regularly in ambient temps freezing or below, you may have issues.
YMMV though I guess.
I was able to charge the EB3A up from 79% to 100%. Of course it didn't go all the way at 199W. The charge rate slowed down for the last 20% or so, but that is normal and desirable to help prolong the life of the battery cells.
Not sure what conditions that amazon reviewer had when testing the 300W with an EB3A, but it if was a warm day it's probable that the Voc was *just* low enough for it to work.
So, I guess I would conclude that if you have an EB3A (or many other solar generators that also have a 12-28V 200W MPPT) then the Massimo may be OK if you primarily plan to use it in higher ambient temperatures. Still, you may have to "massage" it by only exposing 1-2 panels, allow charging to begin, and then fully unfold and tilt as needed. If you need to use it regularly in ambient temps freezing or below, you may have issues.
YMMV though I guess.
Thanks
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I had an old Renogy portable solar panel that also didn't have an ETFE layer and it's kind of warped and bended in odd places now and kind of falling apart. The glue or sticky substance that helped hold the panel in place to the fabric surrounding the panels has come undone. Probably I used it too frequently like several times a week before so being in the sun so often caused it to kind of fall apart.
I had an old Renogy portable solar panel that also didn't have an ETFE layer and it's kind of warped and bended in odd places now and kind of falling apart. The glue or sticky substance that helped hold the panel in place to the fabric surrounding the panels has come undone. Probably I used it too frequently like several times a week before so being in the sun so often caused it to kind of fall apart.
I looked online and PET is smooth and highly reflective, while the panels on mine have a slight texture to them and are kind of like an anti-glare computer monitor.
As to the fabric backing, the stitching is sewn through the edges of the panel and not just held in by glue and fabric pockets.
Since I mainly expect to use these during power outages and maybe short periods outdoors, and don't expect to expose them to more than a little rain, I am hopeful they will last for a pretty long time.
While my expected use case is for up to a couple weeks following a hurricane or winter storm, I do have some rigid panels if there is a collapse of the power grid and I need to use them for an extended period of time.
I looked online and PET is smooth and highly reflective, while the panels on mine have a slight texture to them and are kind of like an anti-glare computer monitor.
As to the fabric backing, the stitching is sewn through the edges of the panel and not just held in by glue and fabric pockets.
Since I mainly expect to use these during power outages and maybe short periods outdoors, and don't expect to expose them to more than a little rain, I am hopeful they will last for a pretty long time.
While my expected use case is for up to a couple weeks following a hurricane or winter storm, I do have some rigid panels if there is a collapse of the power grid and I need to use them for an extended period of time.
It's PET instead of ETFE, and I'm pretty sure this Massimo one is PET as well. I'm not sure where you saw that PET based portable panels have a highly reflective surface, but mine has a surface that's matte and like an anti-glare monitor as you describe. On my Renogy portable panel, there is also stitching near the edges of the panels to hold them in place but some adhesive is also used and this adhesive has come undone due to being in the sun too long.
It's PET instead of ETFE, and I'm pretty sure this Massimo one is PET as well. I'm not sure where you saw that PET based portable panels have a highly reflective surface, but mine has a surface that's matte and like an anti-glare monitor as you describe. On my Renogy portable panel, there is also stitching near the edges of the panels to hold them in place but some adhesive is also used and this adhesive has come undone due to being in the sun too long.
In mine the stitching is about 1/4" from the edge into the panels
Any way, PET or ETFE, I'm happy with what I got for $99 x2.
Took the temp in the sun and the panel gets hotter than the box on the back
One thing I noticed is that one of the panels has diagonal cut corners, and the other is a perfect grid. Didn't notice a significant difference in output, but kind of strange
In mine the stitching is about 1/4" from the edge into the panels
Any way, PET or ETFE, I'm happy with what I got for $99 x2.
Anyways, I agree it's still a good deal even for a PET if you're in the market for a 300W portable panel. For me, it's too big and I don't have the space to fold it out where I am.
Quality seams really good. Has nice adaptor cables (almost worth the price alone). Very large, so if you are limited in space look elsewhere. Once set up they do not flop over like some panels do, not ridgid but Simi ridgid. Doesn't look like they will blow over easily in the wind. Set up not the easiest because legs have a y shaped elastic strap that wants to snap back in place, so you have to place one leg at a time on the ground, and by the time you get to the end you have to go back and reset legs. However putting away is a breeze, because legs automatically fold up.
The overall bad feature is that the controller is not water resistant at all. It says in the manual to keep away from humidity. It may be OK in light rain if you zip up the controller pouch
Would I have purchased at original price of $500, no way in he'll. But for $99 Don't think you can go wrong
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