# Costco 100 watt panel 7 amp controller



## Stockton (Jun 21, 2017)

https://www.costco.com/Coleman-100W-Solar-Panel-With-7AMP-Charge-Controller-.product.100349972.html

A generator is a red flag for me. Too much noise. I live
in a condo. Too many will hear it. It just doesn't make
sense. Solar I can climb up on the roof. Place the panel
where its hard for people to see. A 100 watt panel I 
know doesn't produce that much. It would help recharge
batteries mostly.

This seemed like a pretty good deal. I ordered yesterday
with free delivery.


----------



## LunaticFringeInc (Nov 20, 2012)

Wow that seems like a pretty good deal for a 100 watt panel! I may have to try one on for size and see if its really a quality built item.


----------



## paraquack (Mar 1, 2013)

Thanks for the info.


----------



## Gator Monroe (Jul 29, 2017)

The Harbor Freight 100 watt deal has more bells & whistles (But combining the two Kits ) could be great .(Having a Stand Alone Shop or Shed and having secondary system )


----------



## 8301 (Nov 29, 2014)

Looks like a good deal to me... and it never needs gas or screams "noisy generator".


----------



## sideKahr (Oct 15, 2014)

Just a FYI. I have a 100 watt Renogy panel, with an inexpensive PWM controller. In good sun at noon it produces 18.9 volts @ 5.3 amps.

You would think that's great, but it has yet to charge my 2-battery deep cycle 12 volt setup. I keep fooling with it, and I've spoken with the technical people at Renogy, but I can't seem to get a full charge out of it.

I hope you get better performance from yours, @Stockton .


----------



## Kauboy (May 12, 2014)

sideKahr said:


> Just a FYI. I have a 100 watt Renogy panel, with an inexpensive PWM controller. In good sun at noon it produces 18.9 volts @ 5.3 amps.
> 
> You would think that's great, but it has yet to charge my 2-battery deep cycle 12 volt setup. I keep fooling with it, and I've spoken with the technical people at Renogy, but I can't seem to get a full charge out of it.
> 
> I hope you get better performance from yours, @Stockton .


Sounds like you've got a problem there, sir.
You didn't mention a time frame, so I'll assume you mean it *never* fully charges the deep cycle batteries?
Have you put a multimeter to every logical division of the system? Ever notice any backflow voltage from the batteries to the panel?
You might want to check your diodes. If you have a short, the panel could be draining the batteries.

BTW, that's a great deal Stockton!


----------



## dwight55 (Nov 9, 2012)

sideKahr said:


> Just a FYI. I have a 100 watt Renogy panel, with an inexpensive PWM controller. In good sun at noon it produces 18.9 volts @ 5.3 amps.
> 
> You would think that's great, but it has yet to charge my 2-battery deep cycle 12 volt setup. I keep fooling with it, and I've spoken with the technical people at Renogy, but I can't seem to get a full charge out of it.
> 
> I hope you get better performance from yours, @Stockton .


My solar panel arrived the other day, . . . got to get the stuff together for it's mounting and the wiring down to my batteries.

Basically same setup as you have sideKahr, . . .

I put another system together for a church down in Ky, . . . so far it works fine, . . . for a light out by the road on their sign.

On a side note, . . . how are you determining that the panel is not taking them up to a full charge?

May God bless,
Dwight


----------



## dwight55 (Nov 9, 2012)

Double


----------



## sideKahr (Oct 15, 2014)

Kauboy said:


> Sounds like you've got a problem there, sir. You didn't mention a time frame, so I'll assume you mean it *never* fully charges the deep cycle batteries?
> 
> Have you put a multimeter to every logical division of the system? Ever notice any backflow voltage from the batteries to the panel? You might want to check your diodes. If you have a short, the panel could be draining the batteries.


1. Well, since we never get 3 sunny days in a row here in Western PA, its's kind of hard to test. The folks at Renogy said my system would take 3+ days to charge w/ full sun.

2. Yes, I've practically disassembled the thing, checked the voltages everywhere, and reported them to the company. Checked continuity and resistances through all the cables and connections. They really didn't respond to my data; I have the feeling that they think I'm incompetent. Whatever!

I've since bought a second smaller panel from another company. I'm mostly concerned with keeping batteries charged for radios and lighting, and it works fine for that.


----------



## sideKahr (Oct 15, 2014)

dwight55 said:


> ...On a side note, . . . how are you determining that the panel is not taking them up to a full charge?
> 
> May God bless,
> Dwight


Full charge for my AGMs is 12.9 volts with no load. Can't get there with just the panel.


----------



## 8301 (Nov 29, 2014)

sideKahr said:


> Just a FYI. I have a 100 watt Renogy panel, with an inexpensive PWM controller. In good sun at noon it produces 18.9 volts @ 5.3 amps.
> 
> You would think that's great, but it has yet to charge my 2-battery deep cycle 12 volt setup. I keep fooling with it, and I've spoken with the technical people at Renogy, but I can't seem to get a full charge out of it.@Stockton .


Using a PMW controller the voltage will be controlled to about 14.5v so you lose a bit of power thus.... that 5.3 amps means you are pushing about 77 watts into the batteries once the absorb cycle has started. (until the battery reaches the absorb voltage it may accept about 85 watts from that panel/controller) Batteries below about 80% charge are fairly efficient at absorbing that energy but as the batteries get closer to being full they accept less of that 77 watts (absorb cycle) so a 93% full battery may only accept half of that 77 watts with the rest being burned off as heat. It is very hard to charge a battery over 97% capacity.

Now let's look at your 100 watt panel that since you are using a good but less efficient PMW controller that is only putting out about 77 watts at the 14.5v absorb voltage your battery wants after it has reached enough charge to go into absorb mode.

A battery likes to charge at about 10% of it's rated 20 hr capacity. You can get by on charging a battery with a little less power but you really need to charge at at least 7% of the battery capacity to ensure electrolyte mixing for a full charge. 
So, your 100 watt panel putting out about 77 watts or about 6.5 amps. 6.5 amps X 10 = 65 so that panel is perfect to charge a 65 amp/hr 12v battery. You could probably squeak by charging a 100 amp battery with that 100 watt panel but no larger. By the same token since you don't want to charge the battery too fast and hard I wouldn't want to charge a battery smaller than 45 amp hrs with that panel.

Designing a basic solar system that is efficient and protects your batteries takes a bit of math.


----------



## dwight55 (Nov 9, 2012)

sideKahr said:


> Full charge for my AGMs is 12.9 volts with no load. Can't get there with just the panel.


The reason I asked, . . . in the Navy, . . . the volt meter is NOT used to check for charge.

A tool called a Hydrometer is used, . . . and to quote an internet source (that happens to be correct):

"A fully charged battery will test at 1.275 - 1.280 while a discharged battery will read in the 1.140 range. Do not perform a hydrometer test on a battery that has just been watered. The battery must go through at least one charge and discharge cycle in order to permit the water to adequately mix with the electrolyte."

THIS is the best way to test a battery. You do have to have access to the cells, . . . or at least one test cell (we always used the same test cell, . . . so readings were consistent).

EDIT: I don't have my system set up, . . . but this is probably the one I'll go with, . . . it also has a thermometer to allow you to adjust the reading for temperature. That is not a big deal, really, . . . but if you were anticipating predicting how long things might last, . . . it could be good to have.

May God bless,
Dwight


----------



## sideKahr (Oct 15, 2014)

John Galt said:


> ...So, your 100 watt panel putting out about 77 watts or about 6.5 amps. 6.5 amps X 10 = 65 so that panel is perfect to charge a 65 amp/hr 12v battery. You could probably squeak by charging a 100 amp battery with that 100 watt panel but no larger...


Well! That's it then. I have two batteries in parallel for 156 amp hr total. Why didn't Renogy just tell me that? I gave them all my specs.

Thanks very much for your very clear explanation.


----------



## sideKahr (Oct 15, 2014)

dwight55 said:


> The reason I asked, . . . in the Navy, . . . the volt meter is NOT used to check for charge.
> 
> A tool called a Hydrometer is used...


You're right. But I can't do that, my batteries are sealed. They are AGMs. I'm stuck using a meter and a chart.


----------



## dwight55 (Nov 9, 2012)

sideKahr said:


> You're right. But I can't do that, my batteries are sealed. They are AGMs. I'm stuck using a meter and a chart.


Mine are sealed too, . . . but I've got a drill.

May God bless,
Dwight


----------



## 8301 (Nov 29, 2014)

dwight55 said:


> The reason I asked, . . . in the Navy, . . . the volt meter is NOT used to check for charge.
> 
> A tool called a Hydrometer is used, . . . and to quote an internet source (that happens to be correct):
> 
> ...


clarification for some but I'm pretty sure many here already know this.

SGs (specific gravity) readings can't be preformed on AGM batteries. They can be preformed on FLA (flooded lead acid) batteries. Individual cell readings of the specific gravity (SG) is the best way to tell battery cell health and charge level but can not be done on AGMs.

Also, If you have an AGM battery NEVER equalize the battery unless you like popped vent valves and budging battery sides; fire is also a minor possibility. Equalizing is an option to help equalize uneven cells in FLA and Nichol Iron batteries only and something I do every month or so depending on SG measurements. AGM batteries with unequal cells will just die early, do not equalize an AGM battery.

For an AGM battery voltage testing after the battery has rested (no load or charging) for at least 6 hours is about as good as it gets but often will not show a problem a SG meter can show because you can't use an SG meter on an AGM battery. A fully charged AGM or FLA battery will show about 12.73v hydrometer reading @ 80 degrees about 1.277 SG (specific gravity)
90% charge 12.62v, 1.258 SG
80% charge 12.50v, 1.238 SG
70% charge 12.37v, 1.217 SG
60% charge 12.24v, 1.195 SG
50% charge 12.10v, 1.172 SG

But when it comes to FLAs (flooded lead acid) I fully agree that a hydrometer is the best way to go. This is the hydrometer I use. https://www.solar-electric.com/midnite-solar-battery-hydrometer.html
It has a duel dial that automatically compensates for temperature and when checking a lot of cells is faster that the other hydrometers I've used. But,,,, to keep it accurate at the end of each testing session you must suck some clean water through it a few times. If you don't the dials will begin to stick and give erroneous readings.

Keep in mind that temperature compensating hydrometers may take a 2nd reading for the meter to warm up to match the electrolyte temperature. Also all SG meters are only accurate to about .05 so multiple reading of the same cell will fluctuate a bit.


----------



## azrancher (Dec 14, 2014)

John Galt said:


> But when it comes to FLAs (flooded lead acid) I fully agree that a hydrometer is the best way to go. This is the hydrometer I use. https://www.solar-electric.com/midnite-solar-battery-hydrometer.html It has a duel dial that automatically compensates for temperature and when checking a lot of cells is faster that the other hydrometers I've used. But,,,, to keep it accurate at the end of each testing session you must suck some clean water through it a few times. If you don't the dials will begin to stick and give erroneous readings.


The rating for that hydrometer on the site don't sound too good, one says:
*Resolution of readings not as accurate as I would like. Kind of a go, no go reading. (Posted on August 11, 2017)
Would you recommend this product to a friend? Not sure
*
The other one says:
*Terrible piece of equipment. Absolutely a waste of money. Get the regular bulb which is lots less expensive and very easy to use. (Posted on February 10, 2017)
Would you recommend this product to a friend? Never! 
*
No good reviews, so why not go with a regular bulb hydrometer?

*Rancher*


----------



## 8301 (Nov 29, 2014)

azrancher said:


> The rating for that hydrometer on the site don't sound too good, one says:
> *Resolution of readings not as accurate as I would like. Kind of a go, no go reading. (Posted on August 11, 2017)
> Would you recommend this product to a friend? Not sure
> *
> ...


Having used several large bulb type hydrometers I've found that testing the same cell multiple times will result in about the same variances in readings. About .05 in either direction so in my experience the HydroVolt is as accurate as the bulb type. Plus I don't need to worry about breaking the glass tube the bulb type use.
To each their own.


----------



## 8301 (Nov 29, 2014)

azrancher said:


> The rating for that hydrometer on the site don't sound too good, one says:
> *Resolution of readings not as accurate as I would like. Kind of a go, no go reading. (Posted on August 11, 2017)
> Would you recommend this product to a friend? Not sure
> *
> ...


Having used several large bulb type hydrometers I've found that testing the same cell multiple times will result in about the same variances in readings. About .05 in either direction so in my experience the HydroVolt is as accurate as the bulb type. Plus I don't need to worry about breaking the glass tube the bulb type use.
To each their own.


----------



## SGT E (Feb 25, 2015)

I got in 6 of the Costco / Coleman 100 watt panels about an hour ago....I un boxed them from the main box (Beat up by UPS) and inspected each panel in their singular boxes(NOT A SCRATCH!) Looks like good quality and workmanship ! Got a buddy that has several of the Harbor freight panels...he said they come apart or leak after about 5 years so when this route popped up I decided it was time.....So far its a good 777$ spent! Panels have a 25 year warranty.

I'll be running 5 of these through one larger controller and running a single 100 watt panel to a small AGM for my security camera's and alarm system.

BTW I have a Harbor Freight panel set / 100 watts and it's quite a bit larger than these panels.

Thank you for the info @sideKahr !


----------

