Mirlen's Solar Saga - The Beginning of Another Addiction

[Mirlen]

Stage 1 - The Beginning of another addiction.

2x 100w EcoWorthy panels
1x PWM Charge controller
Mount: Whatever I thought about leaning it on, usually small poolside tables that I turned thru the day to hit 1kWh/day, aka, manual 1 axis tracker with 1 hour resolution.

Price out whole home solar install. Receive $80k-100k quote, wife says if you want solar you need a different wife, no panels on roof...OK, well lets work with what we got!

 

[Mirlen]

Stage 2 - PWM? PFFT, MPPT!

Victron 100/30 charge controller upgrade, more stats, more fun!



The first 1kWh day:

 

[Mirlen]

Stage 3 - Hey look I sold some stuff on eBay, SOLAR FUNDING!

2x JJN 200w Bifacials
1x Victron 150/45 MPPT upgrade, need more volts for 'the plan'
2x JJN 41" angle brackets
1 Raspberry Pi2, USB to VE Direct cable, VenusOS install for VRM integration==stats everywhere.

...realization, I need a battery budget...this 12v 50Ah ain't gonna cut it... FYI: 30 amps on 12 gauge works, for a little while (don't do this)...how am I gonna mount these things on this slightly twisted up fence with uneven slat spacing...hmmm... 2 low profile unistruts horizontally with the top 2x4's? Hmmmm...dang it, nobody has unistrut in stock locally! Whatever, ordered 2 more JJN 200w bifacials for motivation to figure it out and 2 more mounts. Some light load testing pushing the little battery a bit momentarily, incandescent lightbulbs are handy for keeping your stats up Had a good day to push them a bit and hit just over 370 watts but didn't wanna push it, but pretty happy with the panels, they seem to deliver pretty well vs. the 100Ws!

 

[Mirlen]

Got the other panels in so ready to figure out the mounting. Gonna do the low profile unistrut on the fence face to get a relatively flat surface for the mounts and it'll allow me to position them anywhere along the strut...



Getting the supplies ready while waiting for the helpers to come home from school...

 

[Mirlen]

Helper at work!



Helper running away...



...another...



Got one more after this but was racing against sunlight...I made 4-5 trips to Lowes today (Measure 8 times cut 14 times)...and still managed to underbuy for the bolts to hold the mounts to the strut *sigh* oh well, it'll be a 3 panel array for tomorrow and 1 panel gets an inside vacation! So far it seems to be working pretty good using the Unistrut. Fence isn't the straightest and definitely isn't level, won't be perfectly snugged together but should be good'nuff to pass the wife test, maybe... The wingnut and knobs were promptly ditched as you can't put panels right next to each other with those sticking out...man, hardware runs up in $$$ fast, now I gotta figure out what I can return from my pile of leftovers...

That tree thingie near the gate will be gone, it casts shadows too close to my panels....along with a couple others, they have a mind of their own and don't grow straight no matter how many tethers we try to use on them...I swear 1 wants to jump in the spa, and the other wants to run away from it.

 

[Mirlen]

4 panels up! Tilt adjusted to 34 degrees or so, 31.8 would be year round optimal but didn't like how the support geometry was working past this tilt. Fence holding, so far.

 

[zanydroid]

Is this temporary for education and testing? I’m not sure that racking (which relies on the boundary fence) is going to have the right resistance to wind lift.

 

[Mirlen]

Is this temporary for education and testing? I’m not sure that racking (which relies on the boundary fence) is going to have the right resistance to wind lift.

We will see. House is a U shape and rear of lot has row of trees so wind shouldn't be TOO hard on it.

 

[curiouscarbon]

inspirational project, thank you for sharing.

looks like plenty to keep the basics and gadgets going independent of grid condition ? nice work

the fence might not be the hulk, either way the construction looks good. nearby structures will naturally slow down wind and temper the forces acting on the panels.

love to see it ️?

 

[Mirlen]

inspirational project, thank you for sharing.

looks like plenty to keep the basics and gadgets going independent of grid condition ? nice work

the fence might not be the hulk, either way the construction looks good. nearby structures will naturally slow down wind and temper the forces acting on the panels.

love to see it ️?

Fence is secured to 5 steel posts on the other side so it's not just wood.

 

[zanydroid]

It’s probably not that expensive (esp compared to $80k you got quoted) to get engineering on wind loads etc done on this. For standard solar racking it’s quite cheap ($300-500 for a PE stamp), however they may insist that you use listed structural components and some pretty burly attachment to the ground.

I’d probably only forgo that / skimp on what my AHJ requires for structural solar panel if I was a mechanical engineer familiar with the calculations thus able to make an informed calculated risk

 

[featherlite]

Your posts are fun to read!

As an aside, here is what the wind did to destroy watchdoc's array.
https://diysolarforum.com/threads/array-destroyed-by-tropical-storm.69690/#post-881129

 

[Mirlen]

Got a SmartShunt so I know which way the electrons are moving on my copper racetrack...added temp sensor too since this is in the garage. This is totally up to code and completely inspected....totally!

 

[Mirlen]

Santa said to order a 48v battery and an All-in-One to make a portable setup...sooo, ordered a LifePower4 rack battery and an MPP-3048, now just need to get some wire and lugs and get this thing planned out...thinking of a small combiner box for 2-4 PV inputs for later possible additional power, need a T class fuse and some stuff for battery cutoff etc but should be a pretty straight forward handtruck build. I wish Victron had a nice all-in-one build but I think the Easy Plus is all they have for US market...really like their component quality/ruggedness...

 

[Mirlen]

Santa tossed in 4 EVE LF304's in my stocking, along with an antigravity generator evidently...

Wanted a clean 12v build from the 4 EVE batteries so used a SFK kit. Went together pretty easily but wiring those terminals can be a PITA...had wires too long and just not enough room to fold them over...



Ran my PC for a little bit on a 700W inverter to test things out.

Finally got that all finished and some sun to start charging it up when I hear some pounding at the door, dang it, I wanted to finish my nap! *sigh* Oh crap, it's gotta be the R+L freight guy....he's 2-3 hrs early, wtf? They're never early.... Rush down and lug the box into the house as best I can and finally just set it up in the newly designated Kitchen Electrical Research Center.



Coming from the JK-BMS where I have full control to a closed Apple like system where I can't adjust limits was a little shocking, and I found myself multiplying and dividing by 4 and 16 a lot trying to figure out where to set things... Not sure I'll use this handcart but it's on it, and it has wheels so ya, we'll go with this for now. All charged up and I must say the cells are all over the place vs. my 4 EVE cells in the 12v. Those were all like 1-4 mV so far (But haven't hit full charge yet). These at full charge were over 100mV apart. Am letting them sit topped up a bit for a while to see how that goes, I believe these cells are all welded bus bars so paralleling them probably isn't an option. Does opening the case on the LifePower4 void your warranty? Doesn't seem to have seals but I'll refrain from poking in there for now...

These are temp test setups. I have a class T fuse awaiting install once I get things mounted along with a decent DC breaker for panel inputs etc and a 12v downconverter to a 12v distribution box with fuses for some 12v mobile action.

Now if I could just find where those antigravity generators went to help move this rack battery....

 

[Mirlen]

The little 12v battery i s still struggling to recharge, darn winter weather...but it's getting there! All 4 cells are staying within 1-3 mV of each other so far with no balancing yet.

The 48v LifePower4 battery however was not working out as well. 1 cell was always low and I was seeing 150-250mV deviation which is really bad, even after a few shorter discharge/recharge/balance cycles. I didn't have a variable V/A PS I could use to charge that cell so I tried bringing the other cells down a bit and then charging the whole thing up again. That was a slow painful process so I ordered a bench power supply. Brought the hungry cell back up and then got the entire pack up to 'full' (BMS limits it from actually BEING full, dang closed systems and passwords, must look into hacking this eventually) and monitored the low cells and nursed them all to within about 2-5mV of each other at the full state....ran some load to bring it back down a couple percent to get out of the knee into the flatlands then charged it up again...still had some deviation higher than I liked in the 20-40mV range, so fed the cells like 16 hungry chicks. I'm now seeing good behavior from the pack so far, settling in around 4-8mV after a charge cycle settles! Cool, good'nuff for me.

I may install a Neey 4A balancer in there eventually. I REALLY hate passive balancers, they're ridiculous. EG4 or their distributors really need to balance these packs out properly. They shouldn't be like this. I wonder how many customers just had a pack replaced when it may have just been a cell imbalance like this. (Hopefully that one cell holds out, will be monitoring it closely)