48v. 1800w off grid system in Pakistan

[Munib]

Hi all

Building a new house and due to sever power shortages thinking of having

All light fans on solar

5 fans. 12 smd and led lights abt 10 watts each


System design

48 v 2000 w with 1000 amp hr battery

Location Jhelum Pakistan. Min 5 sun hrs
All ideas and suggestions welcome

[Sunking]

System design

48 v 2000 w with 1000 amp hr battery

Way too much battery for your panel wattage. 2000 watts at 48 volt battery if you use a true mppt controller only generates 40 amps of charge current. A Flooded Lead Acid battery needs a minimum of C/12 charge current. 40 amp son a 1000 AH battery is only a (1000 / 40 = 25 hours) C/25 charge rate. You need at least 83 amps or 4000 watts of panel wattage to support a 48 volt 1000 AH battery. At 2000 watts you can only support a 48 volt battery of 320 to 480 AH.

Having said all that sounds like even 2000 watts is way too much panel wattage for your needs. It would be in your best interest to sit down and determine how many watt hours you need in a day, then design a system to meet those needs. My guess is you only need or 1/2 to 1/3 of what you propose right now. That would mean you are spending 2 to 4 times as much money than you have to. What I can tell you is if you do what you plan, you will destroy your batteries from chronic under charging. That would be a very expensive lesson.

Take my advice Start over. You will thank me later, and be happy you did.

Start by reading this. Then come back with questions.

[Munib]

Thanks for the reply


Ok so can any one advice on a 500 watt load . off grid solar system . For home
Have min 5 sun hrs in winter

Let's start from scratch
Any and all ideas welcome

[Sunking]

Thanks for the reply


Ok so can any one advice on a 500 watt load . off grid solar system . For home
Have min 5 sun hrs in winter

That doe snot mean anything. How many watt hours per day do you need? 500 watts for how many hours? WATT HOURS = Watts x Hours.

[Munib]

500 w 24 hrs a day
So I guess 12000 watt hr

Input awaiting

[Munib]

Also

No fans required in winters
Full load only in summers
When we have higher number of sun hrs like 8

So we have to factor that 2

.my first calculation was from the link u mentioned above but since am beginner and this is not my field I wait input from some one more knowledgable

[mschulz]

Also

No fans required in winters
Full load only in summers
When we have higher number of sun hrs like 8

So we have to factor that 2

.my first calculation was from the link u mentioned above but since am beginner and this is not my field I wait input from some one more knowledgable

12000 watts / 48 volt = 250 AMPS

250 AMPs x Days of Autonomy (3) = 750 AMPS of Battery

750 / c/10 = 75 AMPS for charging x 48 volt system = 3600 watts solar.

So you need 3600 watts of panels, 750 AMP hour Battery bank wired at 48 volts, a MPPT Charge Controller that can handle 48 volts system and 75 AMP input and a 500-1000 watt 48 volt inverter. Note: Opinions will vary on what you really need but this is a start and you can use the math I did when you really know exactly how much power you will use in a day.

[Sunking]

500 w 24 hrs a day
So I guess 12000 watt hr

You are Joking right? 12 Kwh per day.

Panel Wattage = 3600 watts.
48 volt battery capacity = 1250 AH
MPPT Charge Controller = 80 amps

[Munib]

You are Joking right? 12 Kwh per day.

Panel Wattage = 3600 watts.
48 volt battery capacity = 1250 AH
MPPT Charge Controller = 80 amps

????

[Sunking]

????

That is what it will take.

[Munib]

You are Joking right? 12 Kwh per day.

Panel Wattage = 3600 watts.
48 volt battery capacity = 1250 AH
MPPT Charge Controller = 80 amps

So the calculation ok

[Sunking]

So the calculation ok

You tell us after you read this.