My 2 year second battery, solar and Wit’send rear quarter panel project (2 Viewers)

[Qball]

As @LandCruiserPhil has already mentioned heat kills efficiency a lot! In the hot afternoons the best I can get is about 100W our of 200W panels. In the cooler mornings I have seen 150w of power generated. I now know I can get away with 1 panel but it would take too long and I will be constantly checking it. With 2 I can charge twice as fast once the sun is out and rest easy. Flex panels are pretty light so have 2 isn’t much of a burden besides making your wallet thinner.

 

[musthave]

@Qball thanks for your thread, super informative.

I'm still trying to figure out what's right and wrong with my solar setup. I have 2 Renogy 100W panels going through their controller, it charges the battery ever so slowly. Not enough to power my small fridge that I am trying to run 24/7.

I have the National Luna setup with the monitor in my truck. The 2nd battery charging with alternator goes up to being even with my starting battery. But 2 days later my 2nd battery is at 20% and that I know of there is no load. So I am losing power somewhere that is YTBD. I almost feel like my controller is the drain...

I'm not confident that my Renogy panels are charging although the controller shows the green lights.

I am considering picking up a Victron Energy BlueSolar MPPT 100/30 Charge Controller. Though I think I could get by with less, which one did you buy? The Pico looks really cool, but I can't justify that.

 

[musthave]

Here is my setup / dilemma. How to wire it all up and have it work

 

[Shoredreamer]

@Qball thanks for your thread, super informative.

I'm still trying to figure out what's right and wrong with my solar setup. I have 2 Renogy 100W panels going through their controller, it charges the battery ever so slowly. Not enough to power my small fridge that I am trying to run 24/7.

I have the National Luna setup with the monitor in my truck. The 2nd battery charging with alternator goes up to being even with my starting battery. But 2 days later my 2nd battery is at 20% and that I know of there is no load. So I am losing power somewhere that is YTBD. I almost feel like my controller is the drain...

I'm not confident that my Renogy panels are charging although the controller shows the green lights.

I am considering picking up a Victron Energy BlueSolar MPPT 100/30 Charge Controller. Though I think I could get by with less, which one did you buy? The Pico looks really cool, but I can't justify that.

If your battery is at 20% after receiving no charge for 2 days I’d test the battery first and go from there. I think that’s what you were saying is happening. That should not be happening. Even if the alternator charge on the battery is showing 3 green dots on your NL monitor, a damaged AGM with a small parasitic or <1amp draw can pull that battery down when the battery is receiving no charge.

 

[Qball]

@Qball thanks for your thread, super informative.

I'm still trying to figure out what's right and wrong with my solar setup. I have 2 Renogy 100W panels going through their controller, it charges the battery ever so slowly. Not enough to power my small fridge that I am trying to run 24/7.

I have the National Luna setup with the monitor in my truck. The 2nd battery charging with alternator goes up to being even with my starting battery. But 2 days later my 2nd battery is at 20% and that I know of there is no load. So I am losing power somewhere that is YTBD. I almost feel like my controller is the drain...

I'm not confident that my Renogy panels are charging although the controller shows the green lights.

I am considering picking up a Victron Energy BlueSolar MPPT 100/30 Charge Controller. Though I think I could get by with less, which one did you buy? The Pico looks really cool, but I can't justify that.

I found it puzzling that your Aux battery would drain to 20% in just 2 days with no load. Two possible scenarios are A: the battery is bad or B: it never changed fully. Given your Aux battery is 100AH from your thread it takes a while to charge to full once it's at 20% which for AGM is about 11.5V. Assuming 20% which means you only have less than 20AH left or need 60AH of electricity, that would take 2 100W solar panels 6 hours to charge given full sun at the right angle. or about 1-2 hours on the stock alternator, however with AGM needing 14.7v to charge and stock alternator only does 14.0V you would never get past 80% on the alternator alone. This is why I went with a smart charger instead of disconnect system, you are better off with cheap wet deep cycle batteries.

You are having the same problems I had which is troubleshooting without much of any real data. I highly recommend an ammeter on the secondary battery just to see what's going on. I prefer permanent ammeter because it will also monitor your draws, Victron is very nice just because you have a lot of data. If you go with the victron route I would go with the 100/20 model because it has a big heat sink, the 75/15 model I had didn't have a heat sink and it got really hot and got me worried and that wasn't even mounted. Although the new models have bluetooth built in but they used the low energy version which has very limited range, I would get the old bluesolar models(not the newer smartsolar models) and add the bluetooth dongle, it has awesome range.

I'm guessing that you might have some parasitic draw and didn't have the panels angled to the sun and might even have some shade. ANY shade absolutely destroys your solar output. Also, make sure you run the 2 panels in parallel in case one has shade and won't affect the other panel. Once you hooked up to the Victron and get the app you will realize just how much difference angling the panel and shade makes on amount of power produced.

 

[Irish Reiver]

Looks like I am a fully paid up member of the "Disappointed with Solar" club. I have run a single Renogy panel for a few years using a Morningstar solar controller (I think this is the first mention of Morningstar in this thread - not sure if that tells its own story). My truck can sit at the airport for long periods and the single panel has been good enough to keep the batteries topped up and run the little electronics I have for security (Hotspot, cameras etc).
This summer I bought a cosway fridge / freezer for my camping trips and decided to add another panel to my setup. The fridge only draws 4.2Amps so I would have thought 200watts of solar, even with rubbish performance would still push out more than the required current. Bottom line is that even sitting in the Florida sun (Sunshine State) both panels will not recharge the batteries and run the fridge. My guess is that I might make it to 48 hours if I started with fully charged batteries.
Highest current I have seen 10.5A but this can drop to 1A even with the sun still hitting the panels. I need to start some detailed troubleshooting but my thoughts are that the morningstar controller is doing funky things.

 

[Qball]

Highest current I have seen 10.5A but this can drop to 1A even with the sun still hitting the panels. I need to start some detailed troubleshooting but my thoughts are that the morningstar controller is doing funky things.

Yup sounds about right. If you don’t have the panel close to 90 degrees to the sun then you will not get the power you are expecting. Sounds like you have a ammeter and you should try to experiment with the angle of the sun. When I messed around with ammeter I can get 10-11amp out of 2 100w panels when the sun is 90 degrees but can get only 2-3 amp if at 30 degrees or less. Once you play around with the panels angles and see the power output you will realize you can’t just leave a panel mounted and expect good power generation.

 

[Irish Reiver]

Mine are fixed to the roof rack so unless I fit some fancy solar tracking air suspension to adjust the angle of the truck, I got what I got. I have a feeling the Morningstar is one of the PWM models but have yet to confirm that. If this is the case then I will swap in one of the MPPT versions which should help some.

 

[bj70_guy]

@Irish Reiver - fwiw my Morningstar controller has been great. I use it (Sunsaver MPPT) with a single (good quality, made in canada) 100W mono panel (fixed to roof) and it keeps up with my ARB fridge, even in less than ideal conditions.

I wish it had the geek factor bluetooth monitoring like the Victron, as I don't have any hard numbers to pass along. But I've been really happy with the setup.

 

[Qball]

Mine are fixed to the roof rack so unless I fit some fancy solar tracking air suspension to adjust the angle of the truck, I got what I got. I have a feeling the Morningstar is one of the PWM models but have yet to confirm that. If this is the case then I will swap in one of the MPPT versions which should help some.

This is the exact reason I bought my flexy panels and long cables. When I camped last time I moved the panel with the sun while the 80 was mostly in the shade. Got plenty of power but does require some work repositioning the panel. However the battery was charged very quickly since I was getting 4.5-5 amp the whole time.

 

[FirstFJ60]

This is the exact reason I bought my flexy panels and long cables. When I camped last time I moved the panel with the sun while the 80 was mostly in the shade. Got plenty of power but does require some work repositioning the panel. However the battery was charged very quickly since I was getting 4.5-5 amp the whole time.

Just curious if you are still using your Ctek or switched to redarc DCDC charger

 

[Dave 2000]

I have a single panel that slides out from under the front of the roof rack, and plugs into a socket in the roof.

There is another roaming panel that plugs into the rear bumper, the cable is long enough to be moved around the 80, having the ability to track the Sun is so important if you want your panel to work efficiently.

I cannot go without a fridge so having the best of both worlds with two panels, and the two batteries is a belt and braces approach.

Regards

Dave