Tell me about these panels

[o1marc]

What can you guys experienced in solar tell me about these panel, pros or cons?
https://www.alibaba.com/product-deta...5e68731dTAG2kv

[CaptSquid]

I got more wattage from Home Depot for less money.

[o1marc]

Originally Posted by CaptSquid

I got more wattage from Home Depot for less money.

What items? I found nothing at HD for less than $1/watt. These are $.35/watt

[john61ct]

from specs, great, the high voltage paired with the right Victron SmartSolar MPPT will harvest plenty of power.

Do 1:1 for optimizing for shading

minimum order? shipping cost?

going without effective warranty?

better to buy locally if possible

[Drew Bru]

What about something like this:
https://atlanta.craigslist.org/atl/e...761824633.html
Local, no shipping, no tax. Might have a person to return to if they don't work out for ya. I don't know what this particular seller's deal is....it was just the first ad I saw in your area.

We bought from a guy on Craigslist, turns out he really knows his solar setups and was able to give us a good price on the whole system. He'd been selling systems for years from his garage. He was able to help me with some of the technical aspects and good phone support during my installation. He even crimped some wires for me.

[o1marc]

What's an acceptable amount wattage need for our bus. I know I need to measure the draw on all the items I will have. But considering a nor full build what would be good? Is that kit at 1225w enough, or would double that be better? Again, I assume the color system should be installed before anything else to ensure sealing on any screw holes and able to use nuts and bolts to secure through the roof before any inside ceiling work can be done.

[o1marc]

Are my thoughts correct, that you would want to complete the solar install as one of the first steps in a build?

[john61ct]

The maximum watts that will fit on your roof is the right number.

More "efficient" panels in terms of watts per square area are good.

Different sizes can help ensure no empty space left.

In case you meant Volts, then for MPPT over 40Voc, aka "house" or "24V" panels are better than the mass market "12V" ones, minimum 21Voc IMO.

[Drew Bru]

Originally Posted by o1marc

What's an acceptable amount wattage need for our bus. I know I need to measure the draw on all the items I will have. But considering a nor full build what would be good? Is that kit at 1225w enough, or would double that be better? Again, I assume the color system should be installed before anything else to ensure sealing on any screw holes and able to use nuts and bolts to secure through the roof before any inside ceiling work can be done.

I guess it depends on what your intended uses are. We'll be boondocking and living full-time, so we put about 1100W of panels and 700AH of battery storage. Until we start living in it, though, it's kind of a crapshoot. Our feelings were that it's better to have more than we need than less. For us, trying to add more at a later date, in a location that had yet to be determined, didn't seem worth the hassle. The few hundred extra bucks we spent wasn't a huge deal. Yes the right way to design the system is to calculate your use first...but we don't really know what the real-world usage is until we start living in it.


We added solar after our interior was built out, using box bolts (expansion bolts) through the skin and into the top of the ribs. We didn't go all the way through the ribs (like we'd intended to do) using carriage bolts. If all goes as well as it has so far, it shouldn't be an issue (but I check for any slop after each trip).
In our case, 4 large panels took up about the front half of our bus....2 in front of the hatch, 2 behind it.

[o1marc]

The link Drew for local panels I enquired about that kit with 10 panels instead of 5 and he said $1000 for 2450w.

[FamilyCircus]

o1marc, you might find some through industrial recycling companies. I was able to find 4 panels that were rated for 325 watts at 42v for 100 each and 2 panels that were cracked but usable for 50 each. Ive got 1950 watts of panels going into 1350 Ah of storage battery.

[o1marc]

Wow, just found this site on solar systems in campers and find it extremely helpful in setting up a system.


https://www.explorist.life/diy-campervan-solar/

I'm a very chea......, frugal I'll keep looking until I get the best bang for the buck. I won't mind spending a few extra bucks to have everything new in the solar system.

[Drew Bru]

One thing to be mindful of is to size your battery bank to match your solar array. The charging current should be between 5% and 13%. I don't know all the theory and the specifics and what all, but there have been a few posts about it here by some of the more solar-savvy folks.

Here's a thread on a solar forum about it: https://forum.solar-electric.com/dis...size-to-panels

[joeblack5]

wow 500 watt? I thought that sunpower E series had the largest with 435 watt. The sunpower panel are 81.6" x41.2" . They would fit very efficient on the roof of a bus.
My only concern with panel that large would be the wind load versus the connection / frame work.
They are around used pretty cheap for a high tech panel .


And I am in the camp ..more is better..The charge current is depending on chemistry. It is easy to limit but the nice thing with more is better that you get the charge current with less sunshine or other non optimized condition. dirt... angle..temperature



good luck J

[PNW_Steve]

Originally Posted by joeblack5

And I am in the camp ..more is better..The charge current is depending on chemistry. It is easy to limit but the nice thing with more is better that you get the charge current with less sunshine or other non optimized condition. dirt... angle..temperature



good luck J

I am going that route as well.

The Midnite Classic has a feature that will limit charge current to a safe level while still making full power available to DC loads. That makes "over-paneling " safer for your batteries.

[john61ct]

99% of max charge amps specs are bogus

especially lead banks

my theory is poor wiring being the norm, and US Torts law, lawyers getting involved,

[Vern1]

Look on ebay for used panels.
You can get 10 245 watt 24V panels for under a 1K delivered.
Most are less than 2 years old and have 20+ year service life.

[cadillackid]

id be in the more is better camp... cant your charge controller limit the amount of current going into the batteries if your panels make too much? but to me with weather and actual p[anel temperature being often unknown.. you have a good chance of being able to make enough power with larger panel arrays on cloudy or semi cloudy days.. or if you are parked say in a valley where you end up with more shade hours..



not to mention the sun angles of winter make for less output during the fall / winter, early spring months.

-Christopher

[o1marc]

Originally Posted by Vern1

Look on ebay for used panels.
You can get 10 245 watt 24V panels for under a 1K delivered.
Most are less than 2 years old and have 20+ year service life.

Looks like the going rate is $60ea. for a 245w panel, plus shipping.Most of them coming out of Az.

[o1marc]

Originally Posted by cadillackid

id be in the more is better camp... cant your charge controller limit the amount of current going into the batteries if your panels make too much? but to me with weather and actual p[anel temperature being often unknown.. you have a good chance of being able to make enough power with larger panel arrays on cloudy or semi cloudy days.. or if you are parked say in a valley where you end up with more shade hours..



not to mention the sun angles of winter make for less output during the fall / winter, early spring months.

-Christopher

I agree, in most cases more is better. With 10 panels I'd be at 2450w. I have room for 3920. Would I be better with the larger amount, or am I overkilling it? I'm half considering a roof deck. There are basically 8 roof panels, if I mount 10 panels should I mount them towards the front of the bus, or towards the rear. My guess is deck on the back would be more efficient.