Good news for solar storage

[knieft]

First email reply regarding Aquion Batteries as posted previously (pasted here for convenience):

"Aloha Kirt,

We will be receiving a new shipment of the Aquion S-20+ stacks in April. The price is around $1,200 each and most homes need a minimum of 12 stacks or more. Please describe your existing system and what you expect in terms of performance and we will be able to properly size the battery and give you an accurate quote.

These batteries are truly unique, with many advantages, but they also behave a little differently so the design process is new.

Thanks for your interest.

Peter

Peter Shackelford, President
Renewable Energy Services, Inc."

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So I replied a while back.

After summarizing our system... (24 volt system with two 12 volt 1260 ah forklift batteries in series--charged by 16 75w panels through a PWM and 6 250w panels through a MPPV--Outback FX2524 inverter)

...I replied that 12 stacks seems like way more than we would need, and asked how do they “behave a little differently”?

After a couple weeks, the reply below from Peter...

Aloha Kirt,

Sorry for the delayed response. I lost my internet connection and then lost you in the avalanche of mail that came in finally.

Our batteries are different in that they accept a charge and give back energy a lot slower than normal flooded lead acid batteries. That means that they must be sized correctly to keep current flows within the conditions most acceptable to the battery. Typically, this means that we must parallel a few extra cells into the system to make sure they don’t see an over current. Once sized properly the battery operates comfortably in a partially charged state and is very forgiving under a solar situation where the sun takes a long time over several days to recharge the battery after a long spell of cloudy weather. In short, these batteries are a perfect fit for a residential solar charging scenario.

The battery usually comes as a 48 volt unit but can be reconfigured to 24 volts. You can start out with fewer that 12 stacks and see how they work. It is easy to add more if needed. A stack costs around $1,200 plus delivery and install at your site.

Let me know what you think.

Thanks,

Peter

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I think they cost too much. 12 x $1,200 = $14,400 Plus delivery and install. Even 6 stacks would be more than we paid for our present batteries.

Anyway, I replied:

Thanks for replying, Peter.

Kinda confused. Replacing our current 1260ah @ 24v batteries would take how many stacks? 12? There must be some kind of equivalency math that you do in sizing batteries to systems, no?

And how much is delivery and installation?

Cheers,
Kirt

Cheers,
Kirt

[kalakoa]

some kind of equivalency math

Charge rate and Ah capacity would suffice.

[MarkP]

So by the time you paralleled enough stacks to get sufficient amperage in and out you would automatically have enough amp-hours for several days? That would be different from lead acid batteries. I seem to have only enough amp-hours for one day of normal use but could burn it all in a short time at several kw if I wanted to.