another math problem

[spikebetrayer]

if my 25kw 280ah battery is fully charged and let says i wanted to run a constant 2000w load. How long would the battery hold the load? TIA

 

[sunshine_eggo]

Easy.

25kWh / 2kW = 12.5 hours.

EDIT: I missed the missing "h" and carried it through. Fixed.

 

[time2roll]

The 25 kW needs to be hours or the units cancel to just a number.

25 kWh / 2 kW = 12.5 hours

 

[rmaddy]

What is a 25kW 280Ah battery? Assuming you meant 25kWh then 25kWh / 280Ah = 89.3V. That's a strange battery voltage.

Something about these numbers isn't right.

A 12V 280Ah battery would be 3584Wh and it can handle a 2kW load for 1.79 hours.
A 24V 280Ah battery would be 7168Wh and it can handle a 2kW load for 3.58 hours.
A 48V 280Ah battery would be 14,336Wh and it can handle a 2kW load for 7.16 hours.

Those durations assume you use 100% of the battery capacity which you are not likely to do.

 

[rmaddy]

@spikebetrayer - any clarification on your battery?

 

[MrM1]

What is a 25kW 280Ah battery? Assuming you meant 25kWh then 25kWh / 280Ah = 89.3V. That's a strange battery voltage.

Something about these numbers isn't right.

A 12V 280Ah battery would be 3584Wh and it can handle a 2kW load for 1.79 hours.
A 24V 280Ah battery would be 7168Wh and it can handle a 2kW load for 3.58 hours.
A 48V 280Ah battery would be 14,336Wh and it can handle a 2kW load for 7.16 hours.

Those durations assume you use 100% of the battery capacity which you are not likely to do.

I know right? 25kw or 25kWh at 280Ah I was like

 

[spikebetrayer]

@spikebetrayer - any clarification on your battery?

EVE 280ah 48v16s does that help? I know its really 14kw but i have another 10 KW in another bank

 

[sunshine_eggo]

280Ah * 16 * 3.2V = 14.336kWh, not 25kWh

Runtime would be 14.336/2 = 7.2 hours.

 

[rmaddy]

EVE 280ah 48v16s does that help? I know its really 14kw but i have another 10 KW in another bank

That does help. So you do not have a 25kWh 280Ah battery. You have a 14+kWh 280Ah battery plus another battery that is 10kWh. Assuming that battery is also 48V then it must be about 195Ah. If those two batteries are in parallel then you actually have a 25kWh 475Ah (roughly) battery bank. Please note the importance of correct units. Battery power capacity is in Wh (or kWh), not W (or kW).

Anyway, then your total runtime with a 25kWh battery bank and a 2kW load would be 12.5 hours.

 

[spikebetrayer]

280Ah * 16 * 3.2V = 14.336kWh, not 25kWh

Runtime would be 14.336/2 = 7.2 hours.

you

280Ah * 16 * 3.2V = 14.336kWh, not 25kWh

Runtime would be 14.336/2 = 7.2 hours.

 

[spikebetrayer]

you are correct i left out the part about another 48v battery bank in parallel.