It's Working!!! Sol-Ark 15K, 33.52kW with 67 Panels AC+DC PV, 40kWh SOK Batteries - Photo Diary

[Ryushin]

@Ryushin - Looks like you have a 'comma' instead of a decimal. For example, instead of 3.220 kW in array 1 you have 3,220 kW... a big difference that is throwing your numbers off.

I don't know why PVWatts says it's kWh when their numbers are just Wh. The original PVWatts exported csv files have kWh in them and I just copied and pasted those cells. Unless I'm not seeing something.

Disconnected us from the grid yesterday just before the CME hit. Had a couple of G5s so far. I don't think it's going to be large enough to do any real damage to the grid this time, but who knows.

 

[kolek]

I don't know why PVWatts says it's kWh when their numbers are just Wh.

The numbers on PVWatts are labled in kWh, please see for yourself in screenprints above.

Let's put it another way:
Your electric bill says something like:
"This month's bill is 2136 Kwh."
Doesn't it seem unlikely you would be generating 80,000 Kwh in a month, which would be 40X your monthly consumption?
That would imply that every day, your system is producing more than 1 month's worth of electric power.
Anyway, I'm outta here. Nice system bro.

 

[Jbird905]

I'm confused about this. Your solar array is 33.5kw, if you plug that into PVWatts, assuming you're living even in a super sunny place like Las Vegas, that would be 58,921 kWh/Year, but you're getting 80,000 just for December?

I think this one comment really mixed things up, by using kWh and Wh, when it was only being talked about in kWh.

Ryushin said "PVWatts say I should be able to make over 80kWh during December." - He did not say he was going to make 80,000 kWh, he said 80 kWh. Somehow, you went from talking in kWh to ending in Wh in that one comment.

I don't know why PVWatts says it's kWh when their numbers are just Wh. The original PVWatts exported csv files have kWh in them and I just copied and pasted those cells. Unless I'm not seeing something.

Ryushin, I think when you input your DC size in PV Watts, you might have put in the Wh number, instead of kWh, which is making things look weird in the CSV. For example, when I put in your array 1 just now, I put in 3.22 for the DC size (instead of 3220) and the screenshot attached is what I get. It's very similar data, but PV Watts did output it in kWh as expected. I remember getting mixed up back when planning my stuff. I would put in Wh and get results like I would generate a million kWh. Until I realized I was doing the math (400 watt panels X 40 panels = 16,000 watts DC size), but PV Watts was asking for 16 kWh, not 16,000.

Sorry if any of that is not needed and not trying to over-explain anything. Just trying to help, because your spreadsheet is great, so I was thinking that re-downloading PV Watts in actual kWh values might help it look more "normal."

 

[Ryushin]

I think this one comment really mixed things up, by using kWh and Wh, when it was only being talked about in kWh.

Ryushin said "PVWatts say I should be able to make over 80kWh during December." - He did not say he was going to make 80,000 kWh, he said 80 kWh. Somehow, you went from talking in kWh to ending in Wh in that one comment.


Ryushin, I think when you input your DC size in PV Watts, you might have put in the Wh number, instead of kWh, which is making things look weird in the CSV. For example, when I put in your array 1 just now, I put in 3.22 for the DC size (instead of 3220) and the screenshot attached is what I get. It's very similar data, but PV Watts did output it in kWh as expected. I remember getting mixed up back when planning my stuff. I would put in Wh and get results like I would generate a million kWh. Until I realized I was doing the math (400 watt panels X 40 panels = 16,000 watts DC size), but PV Watts was asking for 16 kWh, not 16,000.

Sorry if any of that is not needed and not trying to over-explain anything. Just trying to help, because your spreadsheet is great, so I was thinking that re-downloading PV Watts in actual kWh values might help it look more "normal."

Yea, that is probably where I went wrong with PVWatts. I just went and re-entered everything in kW instead of W and it all looks correct now. So bad info in, bad info out. LOL. I'll make an edit for what I did wrong. I guess I had too many numbers going around in my head.

 

[1201]

Yea, that is probably where I went wrong with PVWatts. I just went and re-entered everything in kW instead of W and it all looks correct now. So bad info in, bad info out. LOL. I'll make an edit for what I did wrong. I guess I had too many numbers going around in my head.

I thought you meant you should be able to make 80kwh/day during december

 

[Ryushin]

I thought you meant you should be able to make 80kwh/day during december

That is nearly correct. 2422.70÷31 = 78.15 kWh during December.

Total of All Solar Arrays​
Month​	Daily Average POA Irradiance (kWh/m2/day)​	DC Array Output (kWh)​	AC System Output (kWh)​
1​	4.86​	2,748.71​	2,611.23​
2​	4.90​	3,174.89​	3,023.30​
3​	4.94​	4,414.42​	4,206.62​
4​	4.98​	4,921.19​	4,686.18​
5​	5.00​	5,466.88​	5,213.09​
6​	5.02​	5,464.95​	5,215.66​
7​	5.02​	5,402.63​	5,153.60​
8​	5.01​	4,957.64​	4,727.12​
9​	5.00​	4,422.97​	4,218.66​
10​	4.99​	3,619.62​	3,446.90​
11​	5.00​	2,917.09​	2,775.20​
12​	5.01​	2,422.70​	2,295.86​
Annual Total​	4.98​	49,933.69​	47,573.42​

 

[1201]

That is nearly correct. 2422.70÷31 = 78.15 kWh during December.

Total of All Solar Arrays​
Month​	Daily Average POA Irradiance (kWh/m2/day)​	DC Array Output (kWh)​	AC System Output (kWh)​
1​	4.86​	2,748.71​	2,611.23​
2​	4.90​	3,174.89​	3,023.30​
3​	4.94​	4,414.42​	4,206.62​
4​	4.98​	4,921.19​	4,686.18​
5​	5.00​	5,466.88​	5,213.09​
6​	5.02​	5,464.95​	5,215.66​
7​	5.02​	5,402.63​	5,153.60​
8​	5.01​	4,957.64​	4,727.12​
9​	5.00​	4,422.97​	4,218.66​
10​	4.99​	3,619.62​	3,446.90​
11​	5.00​	2,917.09​	2,775.20​
12​	5.01​	2,422.70​	2,295.86​
Annual Total​	4.98​	49,933.69​	47,573.42​

So I don't know where the other party got the idea you meant 80,000 kWh for the month

 

[Ryushin]

So I'm going to expand my battery storage now. After the CME and us disconnecting from the grid during that time I had to run the generator a bit to get us through a morning rain. My wife really does not like how loud the generator is and I'm like, when the grid is down, we'll have power, I don't care how loud it is, within reason. Heck, when there is a power outage, the neighbors won't care either if I give them an extension cord.

On Friday I ordered three more SOK batteries from @HighTechLab and Current Connected. That is the minimum I would need to get through the longer winter days, based on what I saw this last winter. My wife actually came out of the blue and said to order two batteries after the CME, but after seeing the usage numbers, said to get three. I'm quite pleased with being able to get three batteries right now after spending 5K on the heat pump water heater.

I want to expand the storage vertically. The battery rack from Current Connected can handle five batteries, so I'll need to go with something different.

I ordered RackSolutions 55U server rack (102.5" tall) with the 20" depth kit from PC Nation as they had the cheapest price with shipping. RackSolutions themselves is having to charge an additional $300 fee that FedEx has started charging them for oversized items, probably to go via freight instead. The rack is rated to hold 3000lbs, so the batteries at a 100lbs each, shouldn't be a problem. The rack is two weeks out from shipping, but I'm fine with that to save $300.

55U TALL, RACK-111 UPRIGHT POST KIT. REQUIRES RACK-111 DEPTH KIT TO COMPLETE RAC

Rack Solutions 55U Post Kit for 111 Open Frame Rack

www.pcnation.com

Rack Solutions 20in Depth and 24in Width Kit for 111 Open Frame Rack

Rack Solutions 20in Depth and 24in Width Kit for 111 Open Frame Rack

www.pcnation.com

Finding rails to support 100lbs is not so easy. My research led me to the CyberPower rails as they make UPSs and they are inexpensive to everything else out there and seem to be a perfect lengh to fit the 20" deep rack:

https://www.amazon.com/CyberPower-4POSTRAIL-4-Post-Universal-Mount/dp/B00TCELZTK/

I hope with these rails and the SOK batteries I can stack them right on top of each other. Really depends on how close to the 4U of space the SOK batteries are. If there is a 1/16" of space between them, I should be able to stack them right on top of each other. If this works out correclty, I should be able to get 13 SOK batteries in that rack. I'll be securing the top of the rack to the studs and concrete floor, so baring a earthquake, it shouldn't go anywhere.

So going to get bring the battery storage up to 40kWh with the potential of 65kWh in the future. Once everything is in place, I'll update the first post with the parts.

 

[1201]

nice!! for the amount of pv you have even 40kwh of battery is on the low side

 

[Ryushin]

nice!! for the amount of pv you have even 40kwh of battery is on the low side

Oh, I agree there. I want to get to 100kWh. At some point spending more money doesn't get us any more than what we have now and we have diminishing returns. If I can get through the night on battery and we have sun or non rainy cloud day, the system should be able to charge everything back up before the night again. We have the generator if everything goes south. We will look at our finances at the end of the year to see about adding more battery storage to eventually fill the rack, which I hope will be able to hold 13 batteries.

 

[Ryushin]

Received the RackSolutions 55U rack and got it installed and bolted to the floor on the weekend. Mounted the eight batteries into it using the CyperPower 4 post rails. The SOK batteries are a 1/16" of an inch too tall. I can get three of them in there before the spacing gets too far out tolerance and I have to skip 1U and start again. I can get 12 SOK batteries in the 55U rack with 3U not being used at the top. I can possible get 13 batteries in there if I just place the 4th battery from the bottom directly on third battery and have it not sitting on a rail and it will probably be fine. Each rail is rated for 231 lbs.

So overall, pretty good power density. 60 kWh to a rack. I still need to bolt the top of the rack to the studs and I'll probably get to that this month.

I picked up a cheap little hoist from Harbor Freight to lift the batteries up though I did not need it this time around, anything higher and I will for sure:

https://www.harborfreight.com/gambrel-and-pulley-hoist-99758.html

Hopefully we can order the remaining four SOK batteries from @HighTechLab at the end of the year and I can call this project done.... for now.... maybe until I think of something else I want to do with it.

It's pretty cool to watch the Sol-Ark 15K dump 15kW at 275A into the batteries. I just geek out watching this system.

Oh, and the heating pad seed mats fit between the batteries just fine with the gap created by the rails.