CautionToTheWind said:
Welcome to the forum! I think you have to have a certain number of posts to add a link, as I recall. Can you PM the link please?
I want to buy a portable solar panel system to use with my RV. At this point, I don't want to mount it - just carry the panels and put them outside when I don't have hookups and I'm traveling. I've been following the youtube videos on the new Harbor Freight kit, and I think it's more interesting than some of you are suggesting, but I'm not sure about the comparison with traditional aluminum framed panels.
The HB kit does not have traditional monocrystalline or polycrystalline panels. They are thin film amorphous panels that supposedly work much better in high heat and when shaded, which would be a big advantage for RV use since shading and heat changes all the time when we move to different locations.
They are a lot lighter than the aluminum clad panels, so carrying around would be easier. The kit comes with wiring which is a significant savings. It appears to use cheaper connectors (I think AEC and barrel connectors) than traditional panels (I don't know about quality of the wiring or how weather proof they are - probably not nearly as good as traditional panels, but maybe good enough for my use?). One of the youtube videos say writing is a big improvement from the old panels.
They do take up a lot more space on the face because the cells are much less efficient than traditional mono and poly cells, but should be a lot thinner and lighter (there are some new flexible mono panels that also have this advantage, but very little info on longevity, and the wattage rating is often false). Maybe the best solution for roof mounting, but I don't think they would work well for portable - I'd have to build some kind of stand for them. The HB kit comes with built-in aluminum stands for positioning, which would be great for a portable kit.
The old HB panels had cheap wiring with lots of problems with cracking, and the plastic on the panels cracked on the corners and people had water intrusion problems. I'd really like to know whether the plastic housing has been improved, or whether adding some UV protection spray to the frame would help. I don't think we'll know the answer for some time.
I understand that the longevity of thin film isn't as good as traditional cells, but I'm not sure this will be a problem for me when I'm only going to have them in the sun when I'm out RVing.
No one has yet reported much on the charge controller. It appears to be pretty inefficient. Is it PWM? The manual says it has different modes for different voltages - does that mean you have to change the mode manually to prevent over/undercharging your battery? That would be weird. I have a few very cheap PWM controllers that I could use to properly maintain the battery, and maybe at some point investing in an MPPT controller would make sense.
So, I agree with many of you that traditional panels would be better for permanent roof mounting on a house or shed where there are no shading problems. But RV use is different. At $140 or so for the kit on sale, it seems pretty competitive with traditional panels when you add in stands and cabling.
I hope those of you who have purchased it will provide additional information on the controller and build. The few youtube reviews seem to be very positive. It would be nice to have a local source for panels, and thin film is certainly an interesting technology.
I hope we get more comments about the charge controller's operation.