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by 2Gkashmiri 1793 days ago
Thanks. How we see load is, the product advertises 1000 watts so for me that means 1kwh or one unit of electricity. Same for something that is 200 watts or 2000 watts.

I am aware of the solar thing. I have a grid tied system and I sell the energy to grid. I produce around 30 kWh a day which is good.

My problem is storage. If I want to store energy, should I go with 48volt 24 ah battery or 12volt 96ah ? As I said, there will be an inverter giving 220volt output so does battery voltage matter?

1 comments

Again, I think you are making the same mistake in your first sentence. 1000W does not mean 1kwh or one unit of electricity. It is a measure of instantaneous (or maximum instantaneous, there’s no way your pc regularly runs at 1KW unless you’re mining) power consumption, the “now” voltage times the “now” amperage (times the power factor… maybe).

For storage, none of that matters. What you need to look at is the cheapest total capacity in kWh after accounting for conversion losses at your median discharge rate. Let’s say your median consumption is 450W, then you see the efficiency of your inverter with 12V vs 48V input to produce a sustained 220V at 450W. Maybe it’s the same efficiency for both 12 and 48v or maybe one is 85% and the other is 80% so you need to multiply the capacity by that amount to get capacity after inverter conversion losses to account for the only difference between the two setups.