Moved from the sticks into the suburban sticks

Ok, haven't been around for a few years, I am older but not necessarily wiser. I sold my farm with my original solar setup and have moved to the suburbs on two acres. I live in a tornado zone so I would like to install a hybrid grid tie system for net metering with battery backup. I want to keep the price down. A few years ago I bought two pallets of the 205w Evergreen solar panels. I have 10 left and just bought two more from a fellow I originally sold a pallet to. That gives me 2400 watts of solar panels. I would like to keep my battery costs low so I am considering a 24V battery bank. I have used fork lift batteries in the past but they sure do use a lot of water but the price is good for reconditioned batteries. The only 24V grid tie/Hybrid inverter that I can find are the now discontinued XW4024 which I can purchase on Ebay for around $3200. Add to that a 80A or 90A charge controller at about $600 and with the surplus 200A breakers, battery cables and other wiring I have around and by building a 3 string combiner box, plus $2000 dollars worth of refurbished batteries, I would have a 2400w grid interactive system for less then $6000 dollars. Oh yeah, I also need to add a Honda 3000 watt inverter generator for another $2000. Then I think in 2017 I could get a Tesla battery with integrated charger for about the same price. Oh what should I do. Any alternative ideas to this concept will be appreciated. Yes I still live in the country where I need power to run the well to flush toilets and to have water. Natural gas is not available, nor is DSL internet, cable TV or landline phone service.
Comments
a 24V 400ah system has the same storage that a 48V 200ah bank has. And then you can get by with a single 60A MPPT controller.
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
I know you know the routine.... critical vs optional... days of autonomy....etc... that should determine just how big to make the battery... have fun...
KID #51B 4s 140W to 24V 900Ah C&D AGM
CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM
Cotek ST1500W 24V Inverter,OmniCharge 3024,
2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
West Chilcotin, BC, Canada
As Westbranch says, start with the loads.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
My daily loads run about 7Kwh, so my optimal bank would be 20Kwh - 35Kwh Ouch !
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
If you want backup, a generator is a much better deal (especially with propane as fuel; fuel and generator will last longer.) If you want some solar backup you can get an SMA grid tie inverter with their "secure power" feature and run up to 2000 watts while the sun is out; when it's not out, run the generator. If you want some backup power for critical loads (i.e. computers, lights, radio) then computer UPSes are cheap, can be recharged from either source above and are easily replaced every 5-10 years.
Personally I wouldn't try to go with a battery bank unless you were losing power every week for a day or so at a time.
For grid-tie it really is up to you but for offgrid, golf carts just are not anywhere near what you need for a home with more than one person.
If you use an XW your generator choice should really be 240vac.
I also never understand why one with a decent grid would want batteries unless there is a medical or utility issue like Hawaii.
Good to see you again Mike. ! If you need a 24V XW I have 2 spares and a 4548 and a 600V 80A controller gathering dust.
http://members.sti.net/offgridsolar/
E-mail [email protected]
edit:
(argh, my bad, same lead per BB below)
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
-Bill
I do know that alot of my clients (in the real world) know that a 24V 1,100 AH bank is about the capacity they need to live in a home with 3 or 4 people. There are of course people who need more storage and the jump to a 48V 1,100 AH bank is a very nice solution but expensive when they need replacement. I can get L16's shipped most anywhere in the world and so I do not even look at othere sizes.
I know there are other ways to do this but I really like it simple and the Surrette, US, and even the rediculous Trojan 2V cells are all I look at for an offgrid home.
The OP needs to know a number and with his experience he probably does. The difference in the 1,100 ah batteries I use is $3,600 @ 24V and $7,200 for a 48V lead acid bank. Quite a bit more for AGM lead acid.
Nice that the days a getting longer again!
http://members.sti.net/offgridsolar/
E-mail [email protected]
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
2 volt is often best because one bad cell is easily replaced without tossing a group of good cells. I have a small batch of old 8Ds with five good cells and one bad cell. Nothing but scrap. I doubt that 12 volt batteries are the way to go unless their quality is very high.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
My comments often do not apply to many here because my market is for people in large homes who do not have fun with this stuff but expect flawless results!
http://members.sti.net/offgridsolar/
E-mail [email protected]
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
" I don't care how it works, I just want it to work when I need it to". Hope your clients are a little more understanding and interested in your efforts.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Not many of them would accept going outdoors to dry their hair when they have to be at xyz in 45 minutes. Maybe one of them....
Merry Christmas! Some Spicey Thai lime sauce and shrimp with a cold one later
http://members.sti.net/offgridsolar/
E-mail [email protected]
http://members.sti.net/offgridsolar/
E-mail [email protected]