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recommended inverter size Help

mahdi89

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Joined
Aug 31, 2021
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133
I use about 61.44 kwh
9 hours average sun hours

how many kw inverter do i need? is 5kw enough? do i need and what the size of 48v lifepo4 do i need if i want to go completely off-grid?
and how many watt panels do i need
thank you
 
You need to provide better information.
61.44 kWh's doesn't mean anything unless you tell us over how much time its used. Is that per month? Per day? per hour?

How much energy do you use per month?
What is your largest load and what kind of load is it? Heater? Motor?
Where are you located? The number of panels you need in Canada is different than what you need in Florida.

61.44 sounds like a daily thing.. is that true? Is this a home with an air conditioner being included in that draw?
 
You need to provide better information.
61.44 kWh's doesn't mean anything unless you tell us over how much time its used. Is that per month? Per day? per hour?

How much energy do you use per month?
What is your largest load and what kind of load is it? Heater? Motor?
Where are you located? The number of panels you need in Canada is different than what you need in Florida.

61.44 sounds like a daily thing.. is that true? Is this a home with an air conditioner being included in that draw?
yes it daily
3 AC 0.8 tons each around 8 hours
1 fridge and 1 freezer..
 
61.44kWh per day is an average of 2.56kW. So in theory you could use a 3000W inverter. But you might actually need 10kW part of the day and only 1kW during other parts. So knowing your daily usage doesn't really help anyone offer a suggestion on the best inverter size for your needs. You need to do an energy audit and determine the most watts you need at any given point in time.

Your daily total power use can help determine the amount of battery and solar you might need.

61.44kWh / 9 solar charging hours = 6.827kW of solar. Divide by some appropriate efficiency factor and maybe you really need 8kW of solar panels. Of course that assumes 9 hours each day. It doesn't take into account days with less sun.

For batteries at 48V you have 61.44kWh / 48V = 1280Ah. But you probably only use 80% so 1280Ah / 0.8 = 1600Ah of 48V battery. That much battery would last you one day if there was no solar to fully recharge them.
 
ok but for 1600Ah battery needed to be charger daily
that my probl;em here
my deye 5kw can charge it at 120A so i need to parallel 2 more ? and add solar panel?
so the battery can drain and charge daily ? from 20 to 100%
 
For the kind of power you want, I would recommend 2x SMA Sunny Island inverters.. They are heavy duty and will start an air conditioner without a problem.. They can also be stacked so you can add more later if you want. As for the battery size, that would depend on what kind of battery and how secure you want to be with energy storage... for how long you want to be able to run without sunshine.

If you go with lead acid batteries, you need a lot of solar array power because lead acid bats die quick if you don't keep them charged up every day.
With a lithium battery, it doesn't mind being in a partial state of charge.

I would also recommend a setup that allows you to plug in a generator to charge the batteries. A lot of these lower end inverters don't allow a generator hookup.

62kWh's daily is a lot of energy.. that's not a small system.

How much array you need will also depend on your location.
 
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