~100kwh for 24/7 off grid home

JoeHam

Photon Sorcerer
Joined
Dec 30, 2019
Messages
2,667
Built in 2007 we used triple pane low E argon windows out of Canada. The name escapes me at the moment.

Oops, not directed to me!
 

redalertdt

Solar Enthusiast
Joined
Feb 17, 2021
Messages
29
We haven't made a final choice yet. Suggestions?
I used Zola, pricey but cut down on window count, up on glass size, and simpilified the design (no grilles etc.). European tilt and turns have 3 gaskets for air tightness and comparatively good U Values. https://www.zolawindows.com

This guy recommends these on the east coast. European Architectural supply. I would have looked into them too (but happy with Zola).
 

tanoshimini

Solar Addict
Joined
Mar 28, 2021
Messages
109
As promised, I've started to document the protocol between the "official" Daly BMS software and the BMS. Anyone that's interested in such things can take a peek, pitch in some help, whatever right over here. I should be able to get the code for this up on github tonight. I'll post a link when I do.
 

tanoshimini

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Mar 28, 2021
Messages
109
I've actually just pushed up my initial sketch -- it doesn't do much other than receive and decode the various documented commands (cell voltages, etc.) I built the packet-decoder as a state-machine, so that it's easy to integrate into the main loop without adding a ton of overhead -- this should make it easier to put the chip to sleep when we're waiting for things. It's designed to fire a callback whenever a valid message is received. I'd like to flesh out a command-scheduler so that it'd be easy to fire different queries at different times, with precise timing -- some kinds of data will change much more quickly than others, and so it will not be necessary to poll everything at the same rate.

My first goal with this will be to monitor the 1st level alarm for temperature (both high and low) and to use that to control a pair of relays: one for the pack heater, one for the cooling fans. This way, I can just program the Daly with whatever parameters make the most sense, and the program on the teensy can simply react to those conditions. Later, I'd like to add canbus to speak to inverters, LoRA, etc. Fun!
 

tanoshimini

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Joined
Mar 28, 2021
Messages
109
Tomorrow, I'll put together a one-panel Enphase IQ7+ system and wire that up to the Victron. We'll see if that's going to work out the way that I think.
 

plaidcabin

Solar Enthusiast
Joined
May 3, 2021
Messages
28
Some LiFePo4 battery companies are now adding bms and a heating circuit to their designs. When the temp reaches below the min, the charging current is redirected to heating circuit until batt is back up to temp.
 

TomC4306

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Joined
Mar 2, 2021
Messages
201
Some LiFePo4 battery companies are now adding bms and a heating circuit to their designs. When the temp reaches below the min, the charging current is redirected to heating circuit until batt is back up to temp.
Correct. But he has already spent >$10000 on batteries. See post #1.
 

tanoshimini

Solar Addict
Joined
Mar 28, 2021
Messages
109
Some LiFePo4 battery companies are now adding bms and a heating circuit to their designs. When the temp reaches below the min, the charging current is redirected to heating circuit until batt is back up to temp.
Yep. They want an absolute mint $$$ for those batteries with builtin heaters, too. I'm not knocking 'em -- they're high quality and well made... but they're very expensive. If I were building a pack to handle short outages, I'd probably use them.

For example:

With Battleborn... 100Ah @ 60v is five of their batteries, at ~$900/each. So, ~$4500 for 100Ah (or $45/Ah.) These would last a long time. With the number that I'd have to buy to hit my capacity target, I'd probably get a bulk discount... though I doubt it'd be huge.

These recycled units I'm using are also high quality, well made units... just used. Each big blue box is 280~300Ah @ 60v, for $2000/each (or ~$7/Ah) -- including the cost of the outdoor enclosure. As I add in the pack heaters and control logic, I'll add less than another $1/Ah to the cost of the packs.
 

tanoshimini

Solar Addict
Joined
Mar 28, 2021
Messages
109
UPDATE: It looks like I'm going to get rained-out again today on my planned one-panel Enphase/Victron test.
 

tanoshimini

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Mar 28, 2021
Messages
109
Just gonna leave this here, with no additional comments...
 

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TomC4306

Solar Addict
Joined
Mar 2, 2021
Messages
201
Pass. Lithium titanate. Not much capacity either. 3wh*32 cells. Or am i missing something?
 

tanoshimini

Solar Addict
Joined
Mar 28, 2021
Messages
109
I found one for sale (new old stock) locally for cheap. I was thinking of buying it to put between a wind turbine and a few Enphase micros, if it checks out. As I understand it, the power straight off a wind turbine is too jittery to work with most micro-inverters. I read a research paper about it.

Or, I could tuck it under my quattro and let it smooth out the load for the batteries. It's not huge capacity, but it's good for millions of cycles.

Not sure.
 

NwCali

Solar Addict
Joined
Apr 27, 2021
Messages
301
Great idea using the job boxes!

Just make sure no one can wheel away all your money/hard work and ruin it all.
 

SalckwareRobert

New Member
Joined
May 28, 2020
Messages
35
Feeling pretty good vs Louisiana, not so good vs Hawaii :p

Louisiana had the highest annual electricity consumption at 14,787 kWh per residential customer, and Hawaii had the lowest at 6,296 kWh per residential customer.
Now maybe. I bet Hawaii was much higher when carter forced them to have the AC set to 68 degrees.
I usually run 22-32kwh a day. Got up to 75kwh for a month when the ac duct separated and I was cooling the crawl space.
But since my plasma tv running 24/7 just died probably be dropping now.
 

tanoshimini

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Joined
Mar 28, 2021
Messages
109
A metal T rod through hole in bottom. They pick it up, rod falls onto batteries bus bars. BOOOM!!!!!! crispy crook.
I think I'll probably just bolt them to the concrete pad I'm going to pour. They weigh ~1000lbs each, so you're not going to move them without heavy equipment.
 

tanoshimini

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Joined
Mar 28, 2021
Messages
109
Pictures!

E3FE9C8E-071C-49E0-A7A3-EC88EA786F50.jpeg35E5811F-E90A-4AA3-A551-949D0F84903D.jpeg9623A73E-C35C-42A6-BFBD-1278428F302B.jpeg

So, after a dry-spell of posting — some progress photos! I used the big bobcat to clear our building lot and had to spend quite a bit of time building out our driveway. Two culverts, some mistakes and 350y³ (~276m³) of 4” (~10cm) road base later... We can now get a fully-loaded triaxle dump truck to drive all the way back to our building lot and be able to turn around and drive out. Yay!

I leveled the area where we eventually plan to put our workshop, and a bit more. In the back corner of that area, I constructed a temporary pad for the batteries and inverter to live on while we build everything out. I was able to use the pallet forks on the bobcat to bring the boxes down from the top of the drive way and put them pretty close where I wanted them on the pad, and then I got in touch with my “inner-egyptian” and used a log and a lever to do the fine movements of the batteries. The batteries are laid out with 1’ (~30cm) between the rows, and 6” (~15cm) between each battery in the rows. This makes everything line up nice and pretty.

Directly in front of that, I placed a 20’ x 12’ x 13’ (~6 x 3.5 x 4m) “Garage-In-A-Box” to act as a temporary workshop. (We’re not too worried about people stealing things because the site is remote, and we’ll be living in a wall tent you’d have to pass well up the driveway.) This will give us a place to charge / use tools as well as stage things that are destined for the house.

We also found a pretty good deal on two pallets of Hyundai 370w mono panels, 54 in total (one pallet pictured). They barely fit onto the trailer — maybe an 1” (~2.5cm) of clearance! I hadn’t checked to see how big the pallets were before I’d ordered them, so this was a bit of luck that we were able to get both pallets on there. We’re a little ahead of ourselves by buying the panels now, but it was a really good deal. We might pull out 6 or 9 of them to setup a small, temporary ground-mount array.
 
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