i see no reason not to be serious about getting by with no more than 1000amp/hrs
and doing so quite nicely!

yes it will take some load scheduling and management, and serious conservation, but

it just galls me no end to see writeups in magazines about so called "green" installations that cost the owner something north of 100,000 dollars!!
with all the bells and whistles and no effort at all to schedule a darn thing.

they want to live just as they did on the grid, with no thinking or concern about anything and all the while stand with their chest sticking out proclaiming to their friends and all the world...

"look at me!!! i am green"

ya, right!!!

rant over :)

bob g

Just a few..
Type of battery.

System voltage.

Stored capacity Verses number of days autonomy.

How deep you are prepared to discharge them daily and those extended periods with little incomming power to recharge.

The above goes to life expectancy of batteries.

Maxium load you expect to draw, ie starting a pump/fridge etc and therefore inverter size.

Where you live ie what are your climatic conditions, which will affect your loads.

Who you live with, dogs are less demanding on power than wives.

And so it goes on.....

Anyway as I said on irc full points to Woof for taking the trouble to produce and post a monthly pole.

For example my house array is only 600AH but there is 12  2 volt 600 ah sonnenscheins

My shed array is....

700. ah main array
550. ah second array

Just a few days ago I overheard the comment that the shipping company hadn't picked up the batteries rotated out of the UPS after 5 years of service.  My ears perked up...

Sure enough:  a pallet containing one layer and most of another of batteries.  36 Exide  Sprinter S12V285Fs.  (Checked several with a multitester and they seemed to be fully charged.  About 10 kWHr at the 1 hour rate (and rated for a 15-minute discharge as well).  Maybe 45 pounds each (about a ton total).  Design life 10-12 years, rated service life (as UPS) 8 years.  AGM so you can use 'em upright or on their sides, and transport them with no special care except to see that they don't get shorted.

We've had four outages in the past couple months.  Tripped-out transformer breaker twice, replacement of transformer with a bigger one, and re-stringing of the building wiring to take advantage of the additional power (since it was too wimpy for what we're doing with it - or will be shortly).  Along with previous outages they've probably been through about 6 deep cycles in their lives - just enough to get 'em "trained".

I'd so DEARLY love to take 'em off the company's hands for scrap prices.  It would be ballpark 6 grand worth of batteries probably only half used up and enough capacity to do a fine initial install on an RE system.  Get these and I save maybe half the cost on the initial system.  (Even if they don't enjoy repeated deep cycling they'd still probably last until we'd been settled in to the NV place full time for a while, since we don't get out there all that often and the place idles under 3 kWHr/day when unoccupied, even in heating season.)

But I'm NOT READY for 'em NOW.  B-(  No space to store 'em, would have to put a line-powered charger on 'em to make up self-discharge, might need to improvise connectors (since they seem to use an oddball), etc.

So I didn't pursue them.  Instead I intend to talk to the facilities manager and find out:
 - When we next expect to rotate some out.  (We've got several buildings.)
 - Whether I can take/buy the retired cells.  (California.  Disposal regs?)
 - Who the vendor / service company on the UPS is.  (Given this is Silicon Valley
   they probably have a lot of customers and are doing similar rotate-outs
   much of the time.)

At a place I once worked there was the concept of a "vexing opportunity" - one that had more cost than value, such as distraction from the core project or loss of better opportunities you had to drop to pursue the vexing one.