Stand Alone System powering 3 phase load

[Solariser]

Hi.

I am designing a stand alone system to power a 3 phase load. I need some assistance to make sure I am doing the sizing correctly. My daily energy consumption is 90kwh/day. The irradiance in the worst month is 95 Kwh/m2. My load is 10KW. Can anyone give me some pointers. My peak sun hours are 5hours.

Any assistance would be very much appreciated.

[Sunking]

Hi.

The irradiance in the worst month is 95 Kwh/m2. My load is 10KW. Can anyone give me some pointers. My peak sun hours are 5hours.

95 Kwh/m2 is impossible. There is no such thing as a 95 Sun Hour day. Sure you do not mean 5 Kwh/m2?

Assuming your shortest Sun Hour day is 5 hours and daily consumption is 90 Kwh/day you will need a 27 Kw panel array operating into a 490 volt battery of 1000 AH. You are looking at in USD $ $500,000 to $1,000,000. Of that will be $100,000 in batteries that need replaced about every 5 years. In the first 5 years you electric cost will be roughly $4.54/Kwh. In the USA electricity cost on average $0.111/Kwh

[Solariser]

Hi. Based on 5 hours peak sun I get a similar value for the array size, a bit higher for mine I get 30Kwp.

For the batteries I get a requirement of 15100Ah with a 48V battery system.
Based on Ah = (Daily energy req x Number of days storage) / ( System voltage x DOD x Inverter efficiency x cables efficiency).

So based on using 200Ah batterys I would need 75 batteries.

[Naptown]

Hi. Based on 5 hours peak sun I get a similar value for the array size, a bit higher for mine I get 30Kwp.

For the batteries I get a requirement of 15100Ah with a 48V battery system.
Based on Ah = (Daily energy req x Number of days storage) / ( System voltage x DOD x Inverter efficiency x cables efficiency).

So based on using 200Ah batterys I would need 75 batteries.

what voltage battery?

[Sunking]

For the batteries I get a requirement of 15100Ah with a 48V battery system

It would be almost impossible to run this with as 48 volt battery, and you would need to own a copper mine to cable it out. You are talking industrial application and using industrial equipment and practices. You need to be looking at 400 to 500 volts DC battery.

[Solariser]

So what would I need for this system?. What is wrong with the traditional approach? There are three phase inverters with 48V input and 3phase output rated at 10KW. I appreciate your input and just want to learn more.

[Sunking]

Well let's see 27,000 watts / 48 volts = 563 amps from the panels. Go fing that charge controller and determine the wire size.

[Solariser]

Well let's see 27,000 watts / 48 volts = 563 amps from the panels. Go fing that charge controller and determine the wire size.

I'm planning on using 4 charge controllers rated at 160A each....??

[Sunking]

Personally I would just use one 60 amp 600 volt controller. But heck that is just me because i like to keep cost and complexity to a minimum.

[Solariser]

- If I had 12V batterys of 200Ah each, how many batterys would I need then if I went with a 600V system as you suggested??

- Would I need more batterys than if I went with a 48V system??

- I would prefer a smaller battery bank if it meant paying more for charge controllers.

[SunRayPower]

- If I had 12V batterys of 200Ah each, how many batterys would I need then if I went with a 600V system as you suggested??

- Would I need more batterys than if I went with a 48V system??

- I would prefer a smaller battery bank if it meant paying more for charge controllers.

You would need a VERY large battery to meeting your load. You would also need many charge controllers to insure that you batteries would get recharged each day. It is a huge system.

[Solariser]

I just want to point out that yes I am looking to do this efficiently and economically, but if the system needs to be big in order to meet the demand then big is what it shall be. I am trying to find a good solution, there will always be a better one possibly. So does anyone know how many batterys will be required? Even if it is a 600V system, does anyone know what type of batteries and what configuration is a good solution.

Thank you for your assistance.

[Sunking]

So does anyone know how many batterys will be required? Even if it is a 600V system, does anyone know what type of batteries and what configuration is a good solution.

Yes I do but hesitate to answer because it is obvious you do not understand batteries or basic electrical concepts.

The battery capacity required is 450 Kwh period. If you were to use say 12 volt batteries rated at 900 AH it will take exactly 42 batteries at what ever voltage you configure them as:

12 volt: 42 in parallel = 42 in series @ 504 volts.

[Naptown]

Yes I do but hesitate to answer because it is obvious you do not understand batteries or basic electrical concepts.

The battery capacity required is 450 Kwh period. If you were to use say 12 volt batteries rated at 900 AH it will take exactly 42 batteries at what ever voltage you configure them as:

12 volt: 42 in parallel = 42 in series @ 504 volts.

Yes but the charge voltage would be much higher and the highest input voltage charge controller I found was 600V and only output to max 48 volt (I did not spend a lot of time looking though)

What about this
array feeding 600V to charge controllers, each controller on separate 48V bank, smaller inverters connected to each bank.
combine inverters in panelboard to power load.
Don't know if it will work, never tried before but have put multiple inverters on one service before so they should play well together.

[Sunking]

[QUOTE=Naptown;45549]What about this:

• Array feeding 600V to charge controllers.
• Each controller on separate 48V bank.
• Smaller inverters connected to each bank.
• Combine inverters in panelboard to power load.{/QUOTE]

Yes it would work using consumer grade charge controllers which can go up to 96 volt battery like those made by Midnight Solar. However this is an industrial application which requires industrial solutions and equipment. No offense offered Rich but quit thinking inside the residential box. This system screams 480 volt poly-phase, not 240/120 volt single phase. To do that you need 490 to 600 volt battery voltages.