So I came across this on EBay... and they are very local to me... but it sounds like a $100 experiment gone bad. The specs on this thing are waaaaaaay different than any other 12V solar panel that I've ever seen.Max V 15.03V?Amps at short circuit 7.92?Vmp... 11.97Could someone with more brain power than me check the specs on this and tell me it would charge a Trojan T-1275 without even the need for a charge controller? What about diodes and sucking juice out of the battery and back into the panel?Thoughts? Funky Spec'd 100 watt panel with huge amps.Do you run this with one of Mex's Voltage buck / boosters, then through a charge controller, so that there is enough V to charge a battery properly at bulk mode, 14.8V and give up a few amps in the process?Need help, guys, but in layman's terms, EE's and above need to dumb it down to terms a Finance major can handle.

Those 24 cell, 15v panels were not much use for battery charging because the battery needs 14.5ish to gas and these panels couldn't do it. ( Not enough spread between 15 and 14.5) So they went to 36 cell, 21v panels instead.

15v panels were the big thing for maintaining remote gel emg batteries many years agoThis would be a good maintainer using series diode protectionIt would offer low level slow recharge,Full top off, would take a very long time, but this could work well as storage..Or weekend extenderA boost gizmo would be a big help .. For weekend camping useBut not for storage use

I await mexicowanderer's input on this also.So if you need 14.5ish-15.0V to gas, you need 29 or 30 solar cells at .5V each to get that? At that point, does a charge controller become optional?The amps rating on this solar panel with PWM looks pretty darn good, if you could get the voltage to a usable level to recharge.Surplus voltage or head room, unless under direct sun, no clouds, looks a bit thin.

"Maximum Power Voltage ( Vmp)11.97V"I don't understand this either. I suspect it's in error.

2oldman wrote:"Maximum Power Voltage ( Vmp)11.97V"I don't understand this either. I suspect it's in error.It is not in error, there are only 24 panels on it, at .5V each. Most 12V Battery charging panels have 36 panels on them at .5V each, for 18 Volts output, under maximum load. They then burn some of it off with a charge controller to get it to 14.8 or 14.4V to charge a battery with.This is more a Power Supply panel for day time use, not a battery charging solar panel.

The 12V power source solar panel | Good Sam Community

49 Replies

NinerBikes
Explorer
Oct 22, 2014
mena661 wrote:
NinerBikes wrote:

Amp hours it is. I run a 150W inverter... I need only 3.5 to 4 amps per hour to run a little LCD 22" TV at night..
I have a 26" LCD that draws a little over 2A. You need to upgrade. :)

NinerBikes wrote:

And that right there confirms why you want that Mega Watt adjustability...
Works exactly like I want it to! Still humming away at 13.32V too.

That's why I need to sell my portable 120W solar panel. ;-) Lemme know if you know any one looking for one.

What brand and model 26" TV is at 2 amps?
mena661
Explorer
Oct 22, 2014
NinerBikes wrote:

Amp hours it is. I run a 150W inverter... I need only 3.5 to 4 amps per hour to run a little LCD 22" TV at night..
I have a 26" LCD that draws a little over 2A. You need to upgrade. :)

NinerBikes wrote:

And that right there confirms why you want that Mega Watt adjustability...
Works exactly like I want it to! Still humming away at 13.32V too.
NinerBikes
Explorer
Oct 22, 2014
Snowman9000 wrote:
Almot wrote:
30 AH on a winter day in AZ is possible with 150W, if it stays there all day long. Not 2-3 hours.

Yeah, that's the problem with cheap chargers, they don't see the battery voltage after voltage drop.

I don't know why running inverter at supper time should have any effect on solar. "Supper" is usually something that comes later "dinner", meaning around dusk or later :)...

March 8 of last year at Roosevelt Lake, AZ, I got 54 amp-hours from my 100 watt portable, re-aimed several times during the day. 9+ hour time span. It was a clear day, as you could guess. :)

That's outstanding! One day, in Sept in Montana, with my 120 watt panels, after a brutally cold night, and a bright cold blue norther day the next... I saw 60+ amp/hrs out of my 120 watt portable panel. I was running the forced air heater that morning too while the sun was delivering to the solar panel, taking the amps off the top that the panel was generating.

That said, last January in Q, 30 amps out of the panel was about all I was getting with the short days and 120W panel. Hoping the 150 can get me close to 40 amps. I am hoping a poly crystalline panel wakes up a bit sooner.
JiminDenver
Explorer II
Oct 22, 2014
I am just glad that like solar, there are a lot of people using a variety of batteries successfully because they know the care and feeding. By the time my current batteries need to be replaced, I'll know what will fit my needs best.
NinerBikes
Explorer
Oct 22, 2014
mena661 wrote:
NinerBikes wrote:

Oh, and this pic is specifically for Poor Mena661 :B
Those panels will look good on my MH. Thanks buddy! I assume you'll do the installation too? :B

BFL13 wrote:

Mena was thinking of a pair of 150s to go with the fancy expensive controller he already bought in a fit of madness :) You guys should PM if the haggle price would tempt him. (He is easily tempted but under the thumb of his manager, he keeps saying :) )
Temptations are futile! :B You'll have to pry it from my cold, dead fingers!

BFL, I might get those Renogy 100W poly's. They're narrow and I might be able to get 4 of those on the roof.

NinerBikes wrote:

GC-2's someday in my future, I suppose. Maybe real stuff, Trojan T-105s.
Some people say there is no difference with T105's and other GC's but my batts are EASY to get to 100%. Low 15's for a couple hours and they're full.

And that right there confirms why you want that Mega Watt adjustability... tune it to low 15's for 100%, and then back it off to low 13's for maintenance charging voltages. It also confirms why folks like certain Trojan model batteries, if they are going to spend the money. At some point, I will be done with the free battery T-1275 experiments and move on to T-105s. In the mean time, it's fun, I am learning a lot, and the price was right.

Let's just say that my cell could have been labeled as a Renogy 100w.
mena661
Explorer
Oct 22, 2014
NinerBikes wrote:

Oh, and this pic is specifically for Poor Mena661 :B
Those panels will look good on my MH. Thanks buddy! I assume you'll do the installation too? :B

BFL13 wrote:

Mena was thinking of a pair of 150s to go with the fancy expensive controller he already bought in a fit of madness :) You guys should PM if the haggle price would tempt him. (He is easily tempted but under the thumb of his manager, he keeps saying :) )
Temptations are futile! :B You'll have to pry it from my cold, dead fingers!

BFL, I might get those Renogy 100W poly's. They're narrow and I might be able to get 4 of those on the roof.

NinerBikes wrote:

GC-2's someday in my future, I suppose. Maybe real stuff, Trojan T-105s.
Some people say there is no difference with T105's and other GC's but my batts are EASY to get to 100%. Low 15's for a couple hours and they're full.
BFL13
Explorer II
Oct 22, 2014
JiminDenver wrote:
I'd lower the voltage and let the solar help the battery run the inverter. The volts will come down either way.

if the inverter is to run the microwave for a few minutes just turn off solar for a minute to let voltage drop then start microwave and turn solar back on. If the inverter load is too light to keep voltage below 15 with solar on, that's another thing.

Almot, the pipe at noon is, "Hands to dinner"--- joke added---"officers to lunch" :) One of those class things from the UK like "pants" vs "trousers" and on a raincoat, belt (lower class) or no belt (upper class)
NinerBikes
Explorer
Oct 21, 2014
BFL13 wrote:
Don't forget to "calibrate" your new Solar30 so you know what voltage it will go to above what you set it at.

The T-1275s like to be at 15ish for a good while after they get that high and since they don't gas much, don't lose water much. But meanwhile at that time of day, around supper time, you want to use the inverter for things, so that means keeping the voltage under 15v so the inverter won't alarm off (some have higher limits than 15)

So it is a conflict you have to work around at the time. Disconnect solar, run the inverter, connect solar back up. Or leave solar at 14.9 (which might mean set it at 14.6 or whatever :) )

BTW it is amp hours not amps--you keep doing that!

Amp hours it is. I run a 150W inverter... I need only 3.5 to 4 amps per hour to run a little LCD 22" TV at night.

If I need 120V for anything else, the Honda 2000 gets put into service to run the microwave, or both of them to run the 13.5 AC unit. Probably not necessary to run the AC in AZ this winter.
Snowman9000
Explorer
Oct 21, 2014
Almot wrote:
30 AH on a winter day in AZ is possible with 150W, if it stays there all day long. Not 2-3 hours.

Yeah, that's the problem with cheap chargers, they don't see the battery voltage after voltage drop.

I don't know why running inverter at supper time should have any effect on solar. "Supper" is usually something that comes later "dinner", meaning around dusk or later :)...

March 8 of last year at Roosevelt Lake, AZ, I got 54 amp-hours from my 100 watt portable, re-aimed several times during the day. 9+ hour time span. It was a clear day, as you could guess. :)
Almot
Explorer III
Oct 21, 2014
30 AH on a winter day in AZ is possible with 150W, if it stays there all day long. Not 2-3 hours.

Yeah, that's the problem with cheap chargers, they don't see the battery voltage after voltage drop.

I don't know why running inverter at supper time should have any effect on solar. "Supper" is usually something that comes later "dinner", meaning around dusk or later. Though, different places here in colonies have different uses for this term.

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The 12V power source solar panel

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