100 Watt solar panel testing - Goal Zero, Rock Pals, Aims Power, and another cheap Chinese one from Amazon.

[ArnieC]

I tested some solar panels in the past few days, results are attached.

I am going to keep the Aims Power, it had the greatest output for the size by a pretty significant margin. I went ahead and put MC4 connectors on it and can now connect it to my solar charger or gang a few other panels together for cloudy days or days I am going to be gone from camp for a while and want to follow the sun best I can.

 

[workerdrone]

Thanks for sharing. Interesting that you never saw even close to the claimed output of the panels, I have a Renogy 160w flex panel mounted flat on my topper, same series of controller, and I've seen over 150w indicated on the Victron app. But I do have fat wire in short runs.

 

[Photobug]

Thanks for sharing. Interesting that you never saw even close to the claimed output of the panels, I have a Renogy 160w flex panel mounted flat on my topper, same series of controller, and I've seen over 150w indicated on the Victron app. But I do have fat wire in short runs.

I get nowhere near my panels rated wattage, 50% at best. I have a 30 foot run of 14g automotive wire for a 50W panel.

What sized wires are you using and what length are your runs?

 

[workerdrone]

Guessing maybe 3 feet of 6 gauge? Guessing.

 

[ArnieC]

Wiring was as follows:

Goal Zero: Proprietary 8mm (approx 6 ft) to 15 foot Goal Zero extension cable with Anderson plugs added to the end. 12 gauge stranded from Anderson plug to controller, about 6" long.
Rockpals: Similar setup: Rockpals output to included 8mm adapter to same Goal Zero extension cable used above to Anderson plugs.
Aims Power: Aimspower output cord (16 ga?) (Fork Terminals) stuffed inside comparable size female spade terminals, wrapped with electrical tape, and then 12Ga approx 10 feet to Anderson plugs.

Have since tidied it up and installed MC4 connectors on the Goal Zero and Aims Solar and will retest with a short 12Ga pigtail to Anderson plugs and a longer 14Ga pigtail at my earilest convenience to totally eliminate wiring as a variable and also try some longer runs to see what sort of wattage drop I get.

Goal zero rep told me on the phone that 70 Watts was really good on the Boulder 100 and I shouldn't expect more. Goal zero definitely uses some stringy/thin wire for their setups, even on the 100 and 200 watt panels. Also did not see a published warning about daisy chaining the extension cables hurting efficiency.

It was pretty warm during my test, I have read that affects output but not sure by how much.

 

[Alloy]

I have rooftop panels that I use as portable panels.

It would be interesting to see how portable panels compare to rooftop panels that are both the same size.

 

[ArnieC]

Just got back from four days running the Aims Power set loose on my roof in northern Illinois, parked in the wide open, sun up to sun down. Ran great, collected enough watts even in overcast to keep my battery full enough and my ARB Elements fridge running cool. Fridge was kicked off on medium voltage protection on Sunday AM since Saturday PM was pretty cloudy, but only rose to 32F so the beer was still cold, to the point of slushy. Sunday by 10AM the sun was peeking through the clouds, deployed the solar and in 30 minutes the battery was back above minimum and kicking out the cold again. One thing I have been doing is in the evening while I can still run on solar since the panel puts out more than the fridge draws, is run the fridge temp down to the mid 20s, that way even if I get into voltage protection mode by morning and the fridge cuts out, it only raises up to the low 30s by sunup. Still plenty of cold.

Aims Power has been outstanding so far.

 

[frans]

I tested some solar panels in the past few days, results are attached.

I am going to keep the Aims Power, it had the greatest output for the size by a pretty significant margin. I went ahead and put MC4 connectors on it and can now connect it to my solar charger or gang a few other panels together for cloudy days or days I am going to be gone from camp for a while and want to follow the sun best I can.

Is this a complete connect to batteries and no worry type panel? (For the idiot)

 

[shade]

Fridge was kicked off on medium voltage protection on Sunday AM since Saturday PM was pretty cloudy

You aren't able to power your fridge through one night?

 

[Photobug]

Is this a complete connect to batteries and no worry type panel? (For the idiot)

This is a set of panels and soft case. I would think you need some type of controller either PWM or MPPT to get an efficient battery charge.

 

[Photobug]

One thing I have been doing is in the evening while I can still run on solar since the panel puts out more than the fridge draws, is run the fridge temp down to the mid 20s, that way even if I get into voltage protection mode by morning and the fridge cuts out, it only raises up to the low 30s by sunup. Still plenty of cold.

Are you doing this because the solar to fridge is more efficient than solar to battery to fridge?

It seems like the power to drop the fridge to below freezing might also allow the fridge to keep fridging throughout the night. Would 35 be a better temp to no overchill and hopefully allow the battery to last all night?

 

[DorB]

Are you doing this because the solar to fridge is more efficient than solar to battery to fridge?

The fridge has a very high amp demand for a fraction of a second (spice) to start the compressor running.
Kind of starting the engine.
solar panels cannot provide this demand, so you cannot activate the fridge without a battery in the middle.

On the other hand, the fridge works in intervals, and the panel give (-/+) constant charge.
So a sufficient solar panel actually compensate for the fridges consumption during day time, and if it’s big enough, it can complete the night amp draw of the fridge.



Slowly..

 

[Photobug]

The fridge has a very high amp demand for a fraction of a second (spice) to start the compressor running.
Kind of starting the engine.
solar panels cannot provide this demand, so you cannot activate the fridge without a battery in the middle.

So the fridge could not start up with just a solar panel it needs the battery for the startup spike. Does the startup spike prevent the battery from starting the fridge at night if the battery amperage is low? Since this startup spike is only momentary does that mean it has very little effect on battery SOC but only the ability to start as the battery SOC is reduced?

On the other hand, the fridge works in intervals, and the panel give (-/+) constant charge.
So a sufficient solar panel actually compensate for the fridges consumption during day time, and if it’s big enough, it can complete the night amp draw of the fridge.

Slowly..

I am guessing if you have a large solar array, but not sufficient battery, you could use the solar to over chill the fridge during the day to last all night.

 

[DorB]

So the fridge could not start up with just a solar panel it needs the battery for the startup spike. Does the startup spike prevent the battery from starting the fridge at night if the battery amperage is low? .

Yes.
Sometime people confused between volt and amp.
You can see it when the voltage is above the fridge’s cutoff, the fridge control panel is on, but the fridge won’t start.
From my experience, the fridge is one of the first indicators of a weak battery.

Since this startup spike is only momentary does that mean it has very little effect on battery SOC but only the ability to start as the battery SOC is reduced? .

Yes.

I am guessing if you have a large solar array, but not sufficient battery, you could use the solar to over chill the fridge during the day to last all night
.

Yes..but it’s not ideal for all food products.
Up-down temp change are classics for bacteria development.

Just for experimenting, I’ve connected the fridge to a 3amp battery, and a 60w solar panel, and it worked fine as long as the panel had sufficient sunlight.

The right way is a sufficient battery and solar panel (or to run the engine from time to time).



Slowly..

 

[Photobug]

Yes.
Sometime people confused between volt and amp.

Me included. I would look as voltage as an indicator of the batteries state of charge. Would a lower voltage also indicate a batterie's lack of amp output potential?
Does this vary between battery chemistries? I have seen some Lithium battery claims of crazy amp outputs.

Yes..but it’s not ideal for all food products.
Up-down temp change are classics for bacteria development.

Is bacteria a concern even in the near freezing temps? My wife is a chef and talks about the TDZ (temperature danger zone). 'between 40 and 140 degrees for 2 hours'

Our life has become simpler when we realize there is no room for a fridge in our rig. We are just going to rely on ice or dry ice. Although on a camping trip in July we had a heat wave and a cooler in the cab of the truck the ice was keeping the cooler cold but the top layer of the cooler above the ice felt as hot as the rest of the truck.