It's Working!!! Sol-Ark 15K, 33.52kW with 67 Panels AC+DC PV, 60kWh 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.

 

[Ryushin]

So it's been a year since I first started this thread and it's been a year of production as well. I've attached the Solar Assistant charts and the bill I received today. I have a $564.75 credit with my utility. They dropped the avoided cost to $0.03778 last April when it was $0.05555. So the drop in the avoided cost greatly impacted the amount of credit I could generate. I'll be using some of that credit during the winter when the panels are covered in snow, as they are right now as we are in a middle of a four day snow storm.

I've set a reminder for November 30th to pull the the 12 months of data from Solar Assistant before it rolls over to another month. Does Solar Assistant show the years? The Sol-Ark monitoring is off for 6 weeks during the switch to their own servers this summer, so I can't use that as it's not longer accurate for the year.

Still planning on buying a 5 ton heat pump before the end the year so I can keep using the current R-410A refrigerant before they mandate the switch to the the more expensive and flammable refrigerant starting January 1st 2025.

So I have a demand power charge this month from my utility from 4-8pm that is $3.00 per kW for a $1.72 which was .573 kW. I configured the Sol-Ark 15K to run on battery or solar during this time. But I think there is a natural fluctuation that the Sol-Ark might inadvertently pull some power from the grid even though it's configured not to. The Sol-Ark is configured always buy 0 power from the grid, but it won't let me change it to a negative number so I'm always selling to the grid during this time. This might be a question to ask Sol-Ark if no one knows off hand.

Very happy with the system so far. I want to get the another four SOK batteries to fill that server cabinet and then I'll see where I'm at. I really don't want to be buying any power from the grid during the night and there are days where the AC (soon to be heat pump) is running I might buy 0-16 kWh at night.



Monthly Totals from Solar Assistant. November isn't fully populated so the totals will be a bit higher once November finishes.

Edit: Web site wasn't showing the spreadsheet table correctly, so I attached it as an image.

 

[agtcovert]

Thanks for that parts list, feel like there's something there for everyone! Fantastic install, looks amazing!

 

[1201]

Fantastic.

 

[Ryushin]

Purchased another four SOK batteries from Current Connected. Thank you @HighTechLab for getting them shipped out so quickly.

Bolted the battery rack to the wall using 2x4s, hurricane ties, Simpson strong screws, and two12 inch long half inch thick bolts. It's super solid now and doesn't wiggle in the slightest.

Set up little four foot long trolley riding inside of Superstrut that sits in front of the battery rack. Hooked up the Harbor Freight pulley (had to get longer rope) system to the trolley so I can lift up the batteries by myself and get them stacked into the rack. Note, the picture on the Harbor Freight package shows the rope connected to the pulley wrong, so search on YouTube to see how it's properly set up. When it's done right, there is a little swing lever that grabs the rope and locks it into place so it can hang without you holding it.

It required more effort to use the pulley system then I thought it would. If I was going to do it again, I would maybe consider a cheap electrical wench from Harbor Freight or Amazon. But since I may not have to touch the system again for many years, the manual pulley worked fine. Though having the rope locked into the lever and having the battery hang there doesn't give the warmest fuzzy feeling. Might just be I don't have enough experience such a pulley system to trust it, but either way, it worked fine.

So 60kWh of twelve batteries are now vertically stacked. Finally have enough battery to get through the long winter nights and using the AC during the summer nights. Hopefully everything will continue to be absolutely reliable. Since I had the extra space in the rack, I put the EG4 Chargeverter in between stacks of six and so it will be easy to get to if it's needed. I know the Chargeverter can get warm and if it's a problem, I'll put a fan next to it to keep it cooler. I test the generator and the Chargeverter monthly by running it for an hour and that has been working without any issues. Generator is Tri-fuel and is currently running on natural gas.

Have not had any issues with any of the components used in the system. The Sol-Ark 15K, Growatt MIN-10Ks, and the SOK batteries have worked flawlessly. Everything has worked great so far and I am very pleased with how everything turned out. Looking at our costs and my current electric rates it will take about ten years to break even.

Issue with my electrical utility has been resolved. They had a billing error on their end that was charging me more for demand charge ($3.00 a kW) from 4-8pm. Before they switched out the meter during the summer I'd have about a 15 cent demand charge. After they switched out the meter I was seeing as high as 1.5kW. I thought something was going on with the Sol-Ark but it wasn't. During a day where it showed I used 1.2kW demand charge, I pulled the graph from Solar Assistant and it showed essentially a flat line at 0 during that time. I emailed them my findings and it took them a few days to respond, but they said they confirmed the problem was on their end, the meter was fine, but they tracked the problem down to their billing system. They credited my account the difference for that month and they will go through the previous bills and fix those as well.

So everything is good. Planning on doing a five ton heat pump in the spring. Hopefully that goes well. That's all for now.

 

[OffGridForGood]

Main Positive at very top left, main Negative at very bottom right ?
You can get better balance from the rack if you break them up into smaller sets and then parallel those sets.
Even just two sets of six, with the main positive one battery in from top, and main neg one battery in from bottom of each set should keep two six battery stacks more balanced.

 

[Ryushin]

Main Positive at very top left, main Negative at very bottom right ?
You can get better balance from the rack if you break them up into smaller sets and then parallel those sets.
Even just two sets of six, with the main positive one battery in from top, and main neg one battery in from bottom of each set should keep two six battery stacks more balanced.

I thought about that. I like to keep things simple if possible. I was going to wait and see what the spread is after the batteries top balance for a month. With eight batteries the spread was only about 5%. Right now the spread is pretty extreme around 22%. If it doesn't come into balance within 5-7% I'll probably split them into two sets of six. We'll see what happens.

 

[Brucey]

Potentially connect at the 1/4 and 3/4 points so you aren't too far away from any battery. Current config your middle batteries are far away.

 

[Ryushin]

Potentially connect at the 1/4 and 3/4 points so you aren't too far away from any battery. Current config your middle batteries are far away.

That is a possibility. Never thought about doing it that way, but I can see how that might work. Right now it's the new batteries that have drained faster, but they haven't fully top balanced yet.

 

[houseofancients]

I thought about that. I like to keep things simple if possible. I was going to wait and see what the spread is after the batteries top balance for a month. With eight batteries the spread was only about 5%. Right now the spread is pretty extreme around 22%. If it doesn't come into balance within 5-7% I'll probably split them into two sets of six. We'll see what happens.

i actually had to split, depending on charge/discharge amps, the spread sometimes came up to 35% , which was a bit to much for my personal comfort

 

[Ryushin]

i actually had to split, depending on charge/discharge amps, the spread sometimes came up to 35% , which was a bit to much for my personal comfort

Ugggg.... I hope mine doesn't end up like that. Even a 10% spread I'm not too comfortable with. I guess we'll see what it's like in a couple of weeks.

Connecting at the 1/4 and 3/4 points would also mean having the terminals next to them being uncovered as two connectors would need to overlap, so that is not ideal. Hopefully they come into balance and stay in balance.

 

[HighTechLab]

I would do half and half, then parallel. My primary justification is so that there isn't a single point of failure. The Sol-Ark has two inputs, so this should be quite easy to split up.

Do not do 1/4 and 3/4 points, I just saw someone try that and it was a complete unbalanced mess.

 

[Ryushin]

I would do half and half, then parallel. My primary justification is so that there isn't a single point of failure. The Sol-Ark has two inputs, so this should be quite easy to split up.

Do not do 1/4 and 3/4 points, I just saw someone try that and it was a complete unbalanced mess.

Yea, that is probably the best way. Two sets of six. I have the Homegrid Sol-Ark 15K busbars that combine both of the Sol-Ark inputs.

Looking at your site, I think this will do the job as the Sol-Ark 15K won't output more than 275A:

300A 4-Stud Bus Bars - Distribution Block w/Cover - Red/Black

Designed to streamline and organize electrical connections, our high-performance 300A 4-Stud Bus Bars are suitable for a wide range of applications!

www.currentconnected.com

It would be nice if it was rated for 600A though.

Blue Sea Systems:

https://www.amazon.com/Blue-Sea-Systems-PowerBar-BusBar/dp/B000XBB758

https://www.amazon.com/Blue-Sea-Systems-2708-Connector/dp/B000K2K6MA

This also looks good:

https://www.amazon.com/DaierTek-Distribution-Terminal-Positive-Automotive/dp/B0CQJQFX9Z

The best bet is probably the Blue Sea Systems as from what I've read, it is the highest quality. Also has the highest price to go with it.

Guess I'll watch and see if the batteries balance out and if not, split them up.

 

[HighTechLab]

I would recommend these:

Victron 600A Bus Bar 4-Stud/8-Stud

Efficiently distribute high current and connect batteries or DC equipment with the Victron 600A Bus Bar. Durable, reliable, and versatile.

www.currentconnected.com

 

[Ryushin]

I would recommend these:

Victron 600A Bus Bar 4-Stud/8-Stud

Efficiently distribute high current and connect batteries or DC equipment with the Victron 600A Bus Bar. Durable, reliable, and versatile.

www.currentconnected.com

I like those. And since it's Victron I know it's quality. I think we have a winner. Thank you for posting those. I didn't see those on your site when searching for Busbars. But that is exactly what I'm looking for. Be nice if they had a red cover, but some spray paint will take care of that.