Should I be buying DIFFERENT Solar Panels ?

KnowledgeSponge · May 2013

I've been buying 100Watt, German made Q-cell panels.
Now, it could be a marketing gimmick, but supposedly they're high quality, produce more power per square inch and are smaller and
lighter than "standard" Solar panels of the same output.

Anyone know of these "Q-cell German made" solar cells? So far I've been happy with the quality.

BUT.......

Is ther a "flaw" with buying 100W, 12v panels?

I see a lot of people buying 175Watt and even 230 Watt panels.

Comments are appreciated.

inetdog · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

KnowledgeSponge wrote: »

Is ther a "flaw" with buying 100W, 12v panels?

I see a lot of people buying 175Watt and even 230 Watt panels.

Comments are appreciated.

Unless you have very limited space, what really counts is $ per watt, along with how well the power output is maintained as the panel ages.

Chances are that you are paying a lot more per watt for your nominal 12 volt panels, for use with a PWM charge controller (CC), than you would pay for higher volume, more efficiently manufactured higher voltage panels that can only be efficiently used with either an MPPT CC or with Grid Tie Inverters (GTI)

So the main thing wrong with buying 12 volt panels is that you are paying a lot more than you need to for the same total power. These could either be monocrystaline or polycrystalline silicon cells.

The original German manufacturer went bankrupt in late 2012 and the name (and technology?) are now being used by the South Korean company Hanwha. Are you sure you are getting German made panels? Even before the sale, the actual panels, or at least the cells, may have been manufactured elsewhere.

Thom · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

For me it was price per Watt. The 220w panels were the cheapest if I picked them up so no shipping charge . I was planing on using a Rogue mpt-3024 charge controller . So glad I found this forum . My system works great going on 2 years .

Thom

KnowledgeSponge · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Is $1.65 per watt too much ?

What if you're actually getting better quality panels?

AND......

Does anyone know if there's a place to get good quality panels at good price per watt in Miami Florida?

I can't find any panels in South Florida under $4.00 per watt :-(

inetdog · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

KnowledgeSponge wrote: »

Is $1.65 per watt too much ?

What if you're actually getting better quality panels?

If you shop around, and do well on the shipping, you can get good panels for under $1.00 per watt.
How much you are willing to pay for better quality (and what you are getting) is a decision you will have to make for yourself.

Thom · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Is the warranty better ? Most have 20 years . How are they better ?

Thom

I should have said Icarus system that I copied works great

NorthGuy · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

KnowledgeSponge wrote: »

I can't find any panels in South Florida under $4.00 per watt :-(

You don't need to go far to find better prices. Look right here.

waynefromnscanada · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Not familiar with them, and not much real information on them in searches I made. However, one thing I note is "more power per square inch". If you're paying extra for that extra power/sq/in, that's fine if your space available to mount them is limited. However, if you've got lots of room and not running out of space, then consider going with cheaper, slightly less efficient panels. They'll do exactly the same thing, and you won't notice the difference unless you go up on the roof with a tape measure.
That said, "12 volt" panels are all but a thing of the past, and in many cases cheaper panels of very high quality but with higher voltages are easier to get, and do at least as good a job, even if they do take up a few more inches of roof space. The higher voltage panels will however need MPPT controller to convert the extra voltage to extra current for battery charging, but there will be less power loss between the panels and the battery.

jaggedben · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

The Q-cells panels I'm familiar with were thin-film, which means less power per square inch. Maybe Q-cells has some silicon panels though.

I do know that they have struggled to stay in business and that probably the biggest risk with any panel is that the company won't be around to honor the warranty if they don't last.

KnowledgeSponge · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

jaggedben wrote: »

The Q-cells panels I'm familiar with were thin-film, which means less power per square inch. Maybe Q-cells has some silicon panels though.

I do know that they have struggled to stay in business and that probably the biggest risk with any panel is that the company won't be around to honor the warranty if they don't last.

http://www.ebay.com/itm/321074298642?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

Well, here's the direct product link.....

If anyone would care to take a look and scrutinize :-)

animatt · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

If you are in or near miami I would suggest looking harder. I will not post direct link here about competition, but can say you can get much cheaper panels and even pick them up yourself saving shipping charges. I currently seeing 300 watt panels going for $234 per panel "sharp" brand panels. No minimum purchase. Buying in bulk reduces prices further. 300w is a big panel and is just an example. Customer service at the place in question is iffy but definitely cheap prices.

That is $.78 / watt.
it is 50lbs for 300watts
39.1"x77.6" = 3034.16 sq inches

your panel 17.6lbs for 100watts for 3 of your panels 52.8 lbs so not lighter in this case.
40.15"x26.4" = 1059.96 sq inches and for 3 panels would be 3179.88 sq inches so not smaller either in this case

To mods : If I overstepped in this post feel free to delete it.
Matthew

Cariboocoot · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

animatt wrote: »

To mods : If I overstepped in this post feel free to delete it.
Matthew

Believe me we would.

If this is the place I think it is and you had mentioned it by name it would already be gone. Their behaviour has been so reprehensible that the name is persona non grata around here to the extreme. I personally wouldn't trust them as far as I could kick them.

Of course it could be someone else entirely.

And no, none of the moderators have any connection with the forum host NAWS in any way.

NorthGuy · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

KnowledgeSponge wrote: »

Well, here's the direct product link.....

If anyone would care to take a look and scrutinize :-)

Typical 100W panel will consist of 24 6x6 cells arranged into 6 x 4 grid, so the inner size would be 36 x 24.

So, these panels are not really smaller than typical.

KnowledgeSponge · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

What good would saving a few bucks do if I got a bad panel and they wouldn't make good on it?

PRICE alone isn't everything...true or false?

BB. · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

It is a personal decision... As hard as we try, we cannot spend your money for you.

My choices have not always worked out--Best you can do is filter for obvious con artists... After that, consult your favorite gods and/or spiritual teacher.

-Bill

Photowhit · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Cariboocoot wrote: »

If this is the place I think it is and you had mentioned it by name it would already be gone. Their behaviour has been so reprehensible that the name is persona non grata around here to the extreme. I personally wouldn't trust them as far as I could kick them.

WOW! I guess it's likely where I have purchased 2 times in the last 8 years, not sure what they have done that is so "reprehensible" but I had a panel broken in shipping purchased FOB Miami and they replaced it at their expense, hard to call that poor end service. I'll admit they are more of a wholesaler and I would expect less customer service, but I've dealt with wholesalers most of my life. Also not the place to send a newbie, but if he goes in with his eyes open...

I'll PM him a link and he can make his own choices, shipping on large panels is a huge expense. Something to consider is what kind of charge controller(CC) you expect to use, with 12V nominal panels you could use less expensive Pulse Width Modified (PWM) CC particularly in Florida's heat. Another negative of having multiple panels is fusing them all...

I'll add cautions about 'B' grade panels and UL listing etc...

I have purchased 3 Classic lites, breakers, fuses(?) strain reliefs, and assorted other things from Northern Arizona Wind and Sun (NAWS) where people are likely to be more knowledgeable, and a GREAT Fit for someone starting out!

Cariboocoot · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Photowhit; it has more to do with what happen on the forum with this particular firm.

Which again may be a different on altogether.

Photowhit · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

I recall he was quite rude, I rebuffed him on his 'blog' and he didn't take it down to his credit.

Something to consider is what will you do if you switch panel specs? 12 volt nominal panels are hard to match up with 'grid tie' panels. so stopping and considering, where are you going? ...might help keep you from shooting your self in the foot. How does that go Fire, ready, aim...

Didn't you ask about storing solar equipment?

KnowledgeSponge · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Photowhit wrote: »

I recall he was quite rude, I rebuffed him on his 'blog' and he didn't take it down to his credit.

Something to consider is what will you do if you switch panel specs? 12 volt nominal panels are hard to match up with 'grid tie' panels. so stopping and considering, where are you going? ...might help keep you from shooting your self in the foot. How does that go Fire, ready, aim...

Didn't you ask about storing solar equipment?

Yes.
For some this is a necessity or they desire to be grid tied or off the grid.
For others, it's a hobby.

For now, it's just a hobby for me and I'm enjoying it so far.
All the better that I can "justify" it as an emergency backup source of power
if we lose the grid to a Hurricane for an extended time.

I guess it's a situation of "I'd rather have it and not need it, than need it and not have it."

KnowledgeSponge · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

So I have a quantity of 4, 100W panels.

Now, I'm thinking of buying a quantity of 230 Watt panels. (mainly because it's significantly cheaper per watt.)

So do I need to sell the 4 - 100Watt panels or can I still use them?

Can't I just use 2 separate charge controllers?

inetdog · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

KnowledgeSponge wrote: »

So I have a quantity of 4, 100W panels.

Now, I'm thinking of buying a quantity of 230 Watt panels. (mainly because it's significantly cheaper per watt.)

So do I need to sell the 4 - 100Watt panels or can I still use them?

Can't I just use 2 separate charge controllers?

You can certainly use two different CCs, each with its own set of panels, and connect them to one battery bank. Just make sure that when both of the CCs are in Bulk mode the combined current is not more than the batteries can accept.
If you are very lucky, you may also find that you can parallel some combination of the new panels with series combination(s)s of your old panels into a single MPPT input. That will not be practical with a PWM CC.

BB. · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Yep, you can use two separate charge controllers... I recommend "home run" of wire from each controller directly to the battery bank/ plus&minus buses. That helps keep the electrical noise from one controller confusing the second controller (i.e., daisy change--From battery to controller 1 to controller 2).

The controllers will not be "in sync" all the time--But that is not usually a problem (the controller with the highest voltage setting "wins").

-Bill

Photowhit · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

When your looking for a MPPT controller, I'd suggest the Midnite Classic. Though it won't sync with the other controller, if you buy the soon to be released battery monitor module (Not a big expense around $60) it will measure the current going into the battery from both charge controllers and should be able to make decisions based on the total current, across a shunt just before the battery bank.

KnowledgeSponge · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

BB. wrote: »

Yep, you can use two separate charge controllers... I recommend "home run" of wire from each controller directly to the battery bank/ plus&minus buses. That helps keep the electrical noise from one controller confusing the second controller (i.e., daisy change--From battery to controller 1 to controller 2).

The controllers will not be "in sync" all the time--But that is not usually a problem (the controller with the highest voltage setting "wins").

-Bill

What is a "Home Run" of wires ?

KnowledgeSponge · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Photowhit wrote: »

When your looking for a MPPT controller, I'd suggest the Midnite Classic. Though it won't sync with the other controller, if you buy the soon to be released battery monitor module (Not a big expense around $60) it will measure the current going into the battery from both charge controllers and should be able to make decisions based on the total current, across a shunt just before the battery bank.

Thanks. I'll look into that.

KnowledgeSponge · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

inetdog wrote: »

You can certainly use two different CCs, each with its own set of panels, and connect them to one battery bank. Just make sure that when both of the CCs are in Bulk mode the combined current is not more than the batteries can accept.
If you are very lucky, you may also find that you can parallel some combination of the new panels with series combination(s)s of your old panels into a single MPPT input. That will not be practical with a PWM CC.

Thanks Inetdog,
I have to get a MPPT controller.

BB. · May 2013

Re: Should I be buying DIFFERENT Solar Panels ?

Home Run are a set of wires that run only from the source (battery bus+fuse/breaker) to the destination.

A Daisy Chain would be wiring that runs form the source to load1 to load2 to load3 etc..

For example, your AC home wiring will "home run" from the main panel to the first AC outlet... then "daisy chain" to the next outlet, then the next, etc... Or you will have a home run from the main panel to a single clothes drier AC outlet.

With any charge controller, they are looking for 0.1 volt type resolution... If you put several charge controllers on the same long wire run, they can confuse each other... Each controller is turning on/off the current flow (PWM) so the voltage drop (electrical noise) is uncoordinated between the two (or more controllers). This typically can cause the charge controller to reduce their output current/voltage a bit. This will take longer to recharge your battery bank and reduce peak current flow (all things being equal) vs a separate "home run" from the battery bank bus to each controller (battery "filters out" much of the electrical noise between the controllers)..

-Bill

Should I be buying DIFFERENT Solar Panels ?

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