40kw solar panel system

[Mike90250]

....

Naptown: I which I could buy 48v deep cycle batteries, but they are not sold in Indonesia. Yes, lots of labor and cables to make 48v banks.

That's what you will have to do. It's about the same cables, to put a bunch of 12V batteries in parallel, or 4 of them into series.

BUT, what should work well in your case, is electric forklift 48V battery packs. You would still need several of them in parallel, but you should be able to get them in a big city. You need deep cycle batteries anyway, you cannot (well, you can if you replace them all every 3 months) use regular auto or truck batteries. You will have to buy deep cycle batteries from somewhere, so consider the forklift batteries.

Mike

[Bali88]

That is probable the stupidest thing I think I have ever heard on this forum. You win the prize. At that power levels you are talking about is commercial operation. With Poly Phase somewhere up around 300 to 500 battery voltage.

40 Kw @ 12 volts is 3300 amps. Hope you own a copper mine and have a fire department next door. Heck you will need 40 charge controllers that cost $800 each you moron.

I can see your are passionate about solar.

Yes, it would be a relatively large system and expensive. As far as I can see three SMA Sunny Islands will be enough charging capacity.

Naptown: I which I could buy 48v deep cycle batteries, but they are not sold in Indonesia. Yes, lots of labor and cables to make 48v banks.

[Sunking]

which is around 21,000 ah at 12v .

That is probable the stupidest thing I think I have ever heard on this forum. You win the prize. At that power levels you are talking about is commercial operation. With Poly Phase somewhere up around 300 to 500 battery voltage.

40 Kw @ 12 volts is 3300 amps. Hope you own a copper mine and have a fire department next door. Heck you will need 40 charge controllers that cost $800 each you moron.

[Naptown]

Why on earth are you considering using 12V batteries This would require multiple strings of parallel batteries to get to the AH you need.
At this power level you need to think above 48V batteries and all in a series string.

[Bali88]

So have you built another house or building to hold 42,000 pounds (19,000 Kg) of batteries?

400kwh would be around 10,900kg, but I think I will limit the bats to 250kwh, which is around 21,000 ah at 12v and weights around 6,300 kg. Yes there is a reinforced floor building for that.

[Sunking]

So have you built another house or building to hold 42,000 pounds (19,000 Kg) of batteries?

[Bali88]

Does the following setup makes sense?

The installation is 100% off grid. 230v single fase.
40kw solar panels
300kwh battery pack
45kva diesel generator

Four Sunny MC to the panels and load
Three Sunny Islands to the batteries, generator and load.

Location is Bali, Indonesia

Max load from 9:30 until 2:30pm is 14 kw (all pumps running etc.)
Max load all other times is 10 kw
24 hour period use is 140kw/h

But 10 days a year the maximum load will be 30 kw, this is where the generator is needed. Obviously the Sunny Islands don't have enough power, so generator autostarts when the load is to high (and when battery charge is too low.)

I know this system is undersized, but I don't mind having the diesel genset running once in a while

Many thanks, Sunny