Hi Everyone,
I'm looking to buy solar panels for my Tiny home, unfortunately due to the roof space very limited I'm looking for the smallest size panel with maximum Watts.
I came across this one below, I'm not sure if its even possible to have 380W in small size panel, since the brand is not I ever heard of, I'm questioning if this could be scam.
https://www.starpoweradvancesolartechnology.com/products/380…
Anyone with some knowledge please help.
My roof pitch is 1.42m x 4.6m long
I still remember the '100 MP' (megapixel) digital cameras that used to be sold on New Zealand's TradeMe (like Ebay) back in 2010 when all other digital cameras were around 7MP.
It is possible however I’m also not familiar with this brand.
What are you going to power your appliances at night?
I don’t think it is possible. Solar radiation is about 1kW per square meter. This says it is producing 380W per square meter, a peak efficiency of 38%.
I think the best domestic panels are still 20-25% efficiency, and would expect to pay a very high premium for higher efficiency.
So I think this is just a panel with mislabelled higher wattage.
380w @ 18v… it’s not a solar panel for houses, but more of a camping panel. Are you running a small “off grid” system from 12v batteries?
You would need to size up your system needs and storage first and then work out what panels and controller you are going to need to keep them topped up.
No point buying 5x 400w panels and finding out you only need 2 or, worse, needing 20.
Thank you, I am buying them for a Tiny House, I cant fit standard size one therefore looking for these, I think you are right they are for caravans but I think they will be fine on a Tiny House. I have a Growatt 5KW all in one off grid inverter with MPPT 450V I think and have 10.2KW batteries.
These panels are not suitable for that inverter. Doesn't matter if they fit, you won't be wiring them up to that inverter/battery combo.
That inverter has a startup voltage of 150VDC (+/-10V) ,so 160vdc as a rough min.
You'd need something like 9 to 10 of in a single string to even hit minimum startup voltage. For regular rooftop solar panels that run at 40vdc that's only about 4. Which is that this inverter is designed for.
Perhaps get an actual solar installer to offer some guidance regarding your install limitations, as researching it yourself isn't going to help if you don't know what you're looking for.
Thanks mate, I wasn't planning on installing them, I was just looking to find the ones that could fit on the roof, I have already contacted couple of them and will keep trying. No one seem to have smaller size panels for the job.
@kashxpert: How limited is the dimensions that you are unable to fit a regular rooftop solar panel at about 1040mm?.perhaps an additional angled mounting frame to get more length etc.
I don't think you'll find anything in a small panel suitable for that inverter/battery, as it's just simply a limitation of available solar extractable power and standard output voltages meaning the panels need to be that kind of size.
Smaller panels are aimed at 12v ELV systems, not 240vac inverter setups.
@SBOB: Roof is 1.41m x 4.6m facing north, same area facing south. 2.4m x 3.5m is almost flat with 5 degree pitch to north and south.
Why on gods green earth do you have a 5kw inverter for a tiny house? Not only it way oversized, start up voltage is far higher than you will ever get as pointed out by sbob.
What roof dimensions do you have, someone may be able to help you out based on that.
As pegaxs says, these aren't 'house' solar panels and designed for 12v systems, running to an 12-24v inverter for battery or low voltage DC system operation.
They aren't comparable with roof top solar panels which run at higher voltages (eg 40v) and used for supplying 240v AC inverters.
You are overthinking this. Have a solar installer come out and let them work out what they can fit and how much power plus they will even give you the cost😀
That panel would be a scam (typical Chinese over rating).
From what I have read, the current max power rating is around 225W/m2, based on current technology.
That panel you linked to is 0.93m2, so max possible would be around 210W.
Further information for max. panel power as per below:
https://www.cleanenergyreviews.info/blog/most-powerful-solar…
Thanks mate, agree
Panel efficiency hasn't really improved drastically over the last 5 years, higher rated panels are literally just bigger panels.
The energy per m2 is always going to be pretty much the same no matter what.
Based on the size, and the maximum efficiency that ANYONE has achieved with this type of panel, its a 200W panel.
If it was really a 380W panel it would be being written up in all the scientific journals and industry media as setting a record by a long long long way. It would require all the science of solar panels to be radically rewritten to get that efficiency.
The company selling it are just liars. Like a lot of people who are suckering solar panel buyers by exaggerating the ratings of the products they are selling. That said, $169 for a 200W panel probably isn't a bad price. So you are getting pretty much what you are paying for. You just not getting the output you think you are.
Solar panels are rated at a solar radiation level of 1000W/sq.metre. Any given solar panel technology can only utilise some of the solar spectrum. For silicon panels it is 20-22%, so the best you can expect from them is 220W per square metre. So calculate the area from the dimensions. It comes out at 0.93 square metres, and multiply by 220. That's just on 200W. At best. Hybrid silicon and perovskite panels are still in the laboratory stage, because so far they degrade quickly. They can use more of the solar spectrum. The record for them is about 33%. So even they couldn't give you a 0.93 sq m panel with a 380W output.
Spot on, I agree. Thank you so much for the explanation.
The OP should be aware that he can't install solar himself on his house and connect it to the mains electricity system. He has to use approved panels installed by an approved installer. 12V panels like these are not approved for domestic installation. They are the sort you purchase for an off grid use, like putting them on the roof of your caravan to charge a battery, or to power a 12V pool filter or pump or electric fence or security lighting system.
Op has stated this is a tiny house.
Yes, the OP did state it was a tiny house. But even tiny houses can be sited where there is mains power available, with the expectation of being connected to it. And you can't combine mains power and non-compliant panels and/r installation.
Why can't you fit "normal" sized panels.
I have Jolywood BiFacial 390w that are 1046mmx1773mm. You can fit 2, maybe 3 with non-compliant overhang. It's massively underpowering a 5kW inverter though. Can you put some on the walls?
It's massively underpowering a 5kW inverter though.
Under powering to the point that it will be below minimum startup voltage and just be acting as a paper weight.
with non-compliant overhang
Tiny houses are constructed the size they are so they can be towed to a new location. Non-compliant overhang would require the panels be removed to transport it, or some folding mechanism incorporated in the mounting. Alternatively they'd have to overhang the peak of the roof, in which case they'd catch the wind, and potentially be torn off.
That's why I said non-compliant. There are risks involved.
Thanks for explaining what I knew
What about a (movable) ground mounted installation?
Or a fold up solar panel awning on the sunward side.
That's a good idea
This. If you look at the videos in Living Big in a Tiny House, those with small rooves set up a portable set of panels outside which can be moved to catch the sun, depending on the season.
Edit
Oops. Was replying to @Dslrfirst.
With a name like that I bet it would have to be ‘Chinese watts’ if anything - similar to Chinese lumens and Chinese maH ratings