Which Batteries to Use?

We are building a large solar and battery system in the Southern Caribbean where electric is not very good. The home uses up to 325kWh/Day so we are sizing to 400kWh/Day with about 350kWh of battery storage on site. This will leave me needing about 30000 ah of battery storage on site needed. The electric company here gives no credit if you feed back to the grid for night power etc, also at night the power is horrible. We understand the cost is going to be massive for battery storage but I would like some guidence as to batteries that everyone would use on something like this. We are going to build a battery room etc.

Thanks.

Are you sure you use 325 kWh a day ?
That is almost a month usage around here
Even with only electric heating the house 60 kWh / day is enough.

400 kWh is 48V 8333 Ah. This means that from 304Ah EVE or CATL 48V packs you would need 8333/304 = 27,4 -> 28 pcs.
That is 28 * 16 = 448 cell.
And a lot of inverting power

Well the current 3500sqft home uses up to 161kWh/day average and he is more than doubling the sqft with game room, bar, workout room etc. I usually use battle born but that would make it cost prohibitive.

UrbanCowboy said:

Well the current 3500sqft home uses up to 161kWh/day average and he is more than doubling the sqft with game room, bar, workout room etc. I usually use battle born but that would make it cost prohibitive.

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Wow ... first I would check what eats this lot of power Even an EV eats only 16-26 kWh/100km (and not many drive 200km/day)
Eliminating/optimizing this loads can make the battery-inverter system cheaper.
Lamps to LED, central AC for heating and cooling, ...

Battleborn battery would be extreme expensive. And far from ideal.
The cheapest is built from raw cells like EVE, CATL.
The easiest is from rack battery packs.

What is the max W consumption? Any electric motor driven equipment like pumps?
It will need some inverters
Caribbean, so US split phase 120-240V ?

UrbanCowboy said:

Well the current 3500sqft home uses up to 161kWh/day average and he is more than doubling the sqft with game room, bar, workout room etc. I usually use battle born but that would make it cost prohibitive.

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Sounds like most of the kw is needed for air conditioning . Check out insulating more and heat reflective roof coatings and if you have a enough water source to use water cooled heat exchangers . Also more trees to shade the house from the sun.

UrbanCowboy said:

350kWh of battery storage on site

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Sanity check:

Clearly you need 48V batteries. 350kWh / 51.2V = 6836Ah of 48V batteries. That's almost 70 100Ah 48V batteries. Will just reviewed a 220Ah 48V rack battery. You would need 31 of those. 31 batteries in parallel is insane, not to mention the cost. I suppose with such a large house you could break it up into several separate systems.

Also note that 325kWh/day means a constant 13.5kW load all day. That's a few very large inverters.

The number one rule of living off grid is reduced consumption.

rmaddy said:

would need 31 of those. 31 batteries in parallel is insane,

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With inverters and such that’s gonna run over US$50K probably more, definitely more if not self-installed

All valid points. There is a pool pump with heater and a hot tub, along with a massive amount of AC that the owner likes to keep in the mid 60's.

We are likely going to size for 15kW on the inverter side. At my home in Las Vegas I had 20kW of inverter.

50k is nothing on this really. We aren't going to go after reduction in consumption just up the production and storage.