Briefcase Panels - Help me decide

[Token Civilian]

I'm planning on adding some more briefcase type panels to my Inergy Flex 1500 system. Intended use is as backup for the fridge / freezer / device charging / basic lighting during power outages. Secondary use will be dispersed car camping, where power is desired, hence the desire for briefcase style panels. Note that I'm "sunk" into this system, so can't afford to switch to one of the newer systems (Bluetti, etc). Just looking to max it out, as I have it set up.

For reference, the max input voltage on the Inergy is 90vdc. The "factory" Ascent panels the system came with are 4 x 100 watt in series (Voc = 17.8/ea for nominal max before temp adjust of 4x17.8=71.2). These are $250 / unit.

I have a 2nd battery (~2.1kwh total system capacity), plus the MPPT unit with 2 more solar inputs, for a total of 3. Per the system specs, it's 90 VDC and unlimited amps on all 3 of the inputs.

I'm looking at the Rich 100 and 200 watt briefcase panels. Also in the running are Renology 100 and 200 watt briefcase panels. There's also a Harbor Freight 100 watt briefcase panel.

I have a question into Inergy on doing a series/parallel input to up the wattage / amps without going over the 90Vdc max, so don't yet know what my options are in this direction. Note - all costs will be rounded to whole dollars.

Rich Solar: 100 watt, VOC 22.6, $200 / unit. 200 watt, VOC 22.8, $400 / unit. Either of these will be limited to 3S to stay under the 90 volt max, considering temperature effects.

Renology: 100 watt, VOC 24.3, $239 / unit. 200 watt, VOC 21.8, $390 / unit. Likewise, these are 3s limited.

Harbor Freight: 100 watt, VOC 21.5, $159 / unit. These are borderline 4s, but I'd probably limit to 3s to say safe. Note these are SAE connectors while the others are MC4.

So far, the Inergy 100 watt are out on price. The Renology 100 watt are out on the same metric as the 200's have 2x the nominal and less than 2x the price.

That leaves the the Rich 100 and 200 watt, the Renology 200 watt and the Harbor Freight 100 watt. What are folks opinions on these, relative to each other? Harbor Freight is the cheapest....but I worry about HF's overall reputation, plus a SAE connector vs MC4.

If I 3s the Rich or HF 100 watt panels, on the 2 additional inputs I have, that takes my system to 1000 watts nominal solar input (400+300+300). If I did 3s on either the Rich or Renology 200 watt panels, I'd have 400 + 600+600) = 1600 input watts, nominal.
If Inergy comes back and says 3s2p is good, I could go as high as 400+1200+1200 = 2800 nominal with the 200 watt panels.

Being in the Pacific Northwest brings a couple considerations - 1, the power goes out in winter (like it did 2 days ago and is still out for 60k people in the county) when days are short and nights are long. It is also cloudy a lot. Both of which tend to limit potential total watt-hours of production. To that end, I'm thinking more nominal watts of panels is better, as I could (hopefully) both charge the batteries AND run the fridge / freezer, even with limited production. Renology 200 and Rich 100 and 200 are close enough on price per watt such that isn't a big discriminator between the two. But I'm biased, as noted, toward more watts, so unless there is something compelling about the Rich 100 or the HF (which is a far better price), I'm leaning toward the 200's. Are there other options for 100 or 200 watt briefcase type panels I've missed?

Anyways, opinions please on the best panels given the above. Thanks.

 

[Substrate]

I can't guide you as to which is "best", but I can say that most briefcase style units with rigid panels, tend to put the solar charge controller on the back of the panel. My Renogy 100w is like that.

This is done for convenience, but is not the right spot. The charge controller should be close to the batteries, and not the panel.

In the case of my Renogy, the charge controller is on a swing-out hinge, and is velcro'd to the back of the panel initially. This needs to be carefully pulled away and swung out in normal use. Otherwise, with lead-acid batteries, the ambient temperature sensor in the controller will heat up due to being right on the backside of the panel, and the temperature compensation will be inaccurate.

The real solution, was to remove / replace the controller, and put it near the batteries. But that's not convenient for some. And in the case of LiFePO4, where temperature compensation should be zero/none, it would still be wise to swing the controller away from the back of the panel. Wiser still to put the controller near the battery.

Just some thoughts. Placing the controller near the battery pays off, especially if your run to the briefcase is a bit longer than the length supplied.

 

[42OhmsPA]

How local is harbor freight to you? Can you buy there additional warranty for panels?
You can easily make or buy adapters for the cable.

 

[Doggydogworld]

I'd permanently mount four used Trina 250s or similar. 1000W for $340 instead of $2k. Maybe buy one more briefcase for camping if the 400W you already have isn't enough.

 

[Token Civilian]

I'd permanently mount four used Trina 250s or similar. 1000W for $340 instead of $2k. Maybe buy one more briefcase for camping if the 400W you already have isn't enough.

Until I move to my "permanent" retirement home, I won't be able to. Once I do, then I'll be looking toward a full on permanent system.

42OhmsPA - Actually, there are several in the greater Seattle area which is home to me, not more than 1/2 hour to multiple of them. I'll have to look into the additional Warranty. I didn't know about that. Thx.

 

[brum]

I'm using the Dokio panels. These were from Aliexpress. The prices currently are ~1 USD per watt. I had them for 3 years now without issues. They are lightweight and compact but should be stored on a flat surface without luggage over them.

Two 80W in series are doing at most 8A through an MPPT to 12V LiFePo4.

 

[42OhmsPA]

Until I move to my "permanent" retirement home, I won't be able to. Once I do, then I'll be looking toward a full on permanent system.

42OhmsPA - Actually, there are several in the greater Seattle area which is home to me, not more than 1/2 hour to multiple of them. I'll have to look into the additional Warranty. I didn't know about that. Thx.

No problem.
It's also nice to have a bunch them around for ease of returns.
Note, as Doggydogworld stated, full size panels are much cheaper. ~300W for ~$75 plus some time and fuel.

 

[Doggydogworld]

Until I move to my "permanent" retirement home, I won't be able to.

Doesn't have to be a full grid-tie, roof-mounted solution. Could be a rack attached to a pole in the ground. Or just lean the panels against a wall, with tie-downs to keep them from blowing away. When it's time to move take them with you.

Briefcase portability is worth an extra $1500-2000 to some people, and that's fine. But your original message mentioned cost several times, so it's worth pointing out less expensive options.