What is your actual solar panel current?

[tacomabill]

Wondering how many amps people are actually getting from their solar panels for their lattitude and time of year. I know there are websites for entering all the data to get the theorical output in volts, amps and watts. But that is not real world.

What are you measuring in the field? How are you measuring it? I am especially interested in current output for 200 watt, 12 volt roof-mounted rigid monocrystalline panel in midsummer in northern rockies and in midwinter in desert Southwest.

 

[plh]

1/2 to 3/4 of its optimal rating.

 

[4000lbsOfGoat]

I have done both midsummer in the northern Rockies and midwinter in the desert. I have a 180 watt suitcase unit and a separate100 watt panel. Peak output is about the same for both summer in the north and winter in the south, it'll just run at peak for more of the day in the summer.

The 180 watt unit seems to peak at around 9 amps at 13.7ish volts. The 100 watt unit peaks at about 4.5 amps at 13.7ish volts.

Those numbers come from the solar controller during the Bulk charging stage.

I've done 10 days in the desert in midwinter (literally over the winter solstice, so as little light as possible) with only the 180 watt and had enough sun to fully charge 260 AH of AGM batteries every day. That was with a fridge running all the time (which is minimal in the winter) and a CPAP running for 9-10 hours per night.

 

[plh]

I have done both midsummer in the northern Rockies and midwinter in the desert. I have a 180 watt suitcase unit and a separate100 watt panel. Peak output is about the same for both summer in the north and winter in the south, it'll just run at peak for more of the day in the summer.

The 180 watt unit seems to peak at around 9 amps at 13.7ish volts. The 100 watt unit peaks at about 4.5 amps at 13.7ish volts.

Those numbers come from the solar controller during the Bulk charging stage.

I've done 10 days in the desert in midwinter (literally over the winter solstice, so as little light as possible) with only the 180 watt and had enough sun to fully charge 260 AH of AGM batteries every day. That was with a fridge running all the time (which is minimal in the winter) and a CPAP running for 9-10 hours per night.

So 61 watts from your 100 watt panel and 123 watts from your 180. Sounds about right.

Are you mounted flat or aimed at the sun?

 

[DiploStrat]

I have found the old rule of thumb, 5A @ 12v per 100w of panel, to be pretty close.

More in good sun and cooler weather.

Of course, the actual output will depend on the demand from the battery.

 

[45Kevin]

400 watts of flat laying monocrystaline panels seem to get me 14-18 Amps at high noon in lower Baja. I was expecting a bit more.

 

[4000lbsOfGoat]

So 61 watts from your 100 watt panel and 123 watts from your 180. Sounds about right.

Are you mounted flat or aimed at the sun?

Generally aimed at the sun. Especially in the winter I'm moving panels regularly to keep them lined up.

 

[WSS]

I had to replace my portable 120w panel as it was run over by a prius. My bad for forgetting to take it off the top of my Jeep before driving. I was never really happy with the output. It was rated at 120w but I could never see 70w. I did a short resaerch on this type of panel and rockpals floated to the top. I opted for a 100w panel. It was roughly the same profile as the old ecoworthy 120w panel but much heavier. On testing I got OVER 100w! This was of course optimal angle and full sun but it did produce. The meter was placed before the PWM, so it is not choked to 12v yet.

 

[jonyjoe101]

in southern california san diego area with my 365 watt lg neon panel flat on the roof in the winter I get about 13 amps, in the summer I seen up to 27 amps. With a 240 panel I was getting about 9 amps in winter and about 12 amps in the summer. With a 120 watt panel I got about 5 amps in winter and 6 amps in the summer.
Those of you not getting max performance out of your panels its due to voltage drop. All controller I ever had pwm or mppt were off by at least .5 volts. By raising the bulk voltage on the controller you will see a big increase in amps going to your battery. Measure the voltage at your battery terminals it should be reaching 14.4 volts. One sign that you got voltage drop is your battery going into float too soon and another sign is the controller never going into absorb mode, it just goes straight to float.
On my ecoworthy 20a mppt, I had to increase the bulk setting to 15.5 volts ( the max it would go) to charge my 14.6 volt 220a lifepo4, If I had set the bulk setting to 14.6 volts as recommended, the battery would only charge at 4 to 6 amps with a 240 watt panel. Voltage drop is a major problem especially if your charging lead acid.

This is my 365 watt panel in summer charging my 12.6 volt li-ion 312ah bank. As you can see when the sun is right over head the panel is actually putting out 375 watts as per the makeskyblue 60a mppt. I also have a 220ah 14.6 volt lifepo4 but I rarely see more then 15 amps going into the battery.
The makeskyblue controller has voltage compensation (you can adjust voltage on controller to battery terminals) it works extremely well to overcome the voltage drop.