How Many Amps Is 15 kVA at 100V?

A 15 kVA single-phase load at 100V draws 150 amps. Three-phase configurations are not typical at this voltage. At a load power factor of 0.8 the load's real-power draw is 12 kW (a generator or UPS feeding this load has a separate kW rating set by the manufacturer which must be checked independently against the kVA rating).

15 kVA equals 150 amps at 100 volts (single-phase)

150 Amps

Try: 10kVA at 100V 20kVA at 100V 7.5kVA at 100V 5kVA at 100V

kVA

Volts

Amps (1Φ)

150

Assumes a single-phase AC circuit at the input voltage. kVA is apparent power, so no power factor term is involved.

Formulas

Single Phase

I_(A) = (kVA × 1000) ÷ V

(15 × 1000) ÷ 100 = 15,000 ÷ 100 = 150 A

Generator & UPS Sizing

Load-Side Real Power by Power Factor

A load with an apparent power of 15 kVA draws different amounts of real power depending on the load's own power factor. The table below is a load-side conversion, not a forecast of what a generator or UPS will output for that load: generators and UPS units publish their own independent kW rating set by the engine or inverter design, and that rating is often lower than kVA × the load's PF.

Load Type	Load PF	Load Real Power (kW)	Current at 100V
Resistive (heaters, lights)	1.0	15 kW	150 A
Mixed typical	0.85	12.75 kW	150 A
Motors/HVAC	0.80	12 kW	150 A
Computers/servers (no PFC)	0.65	9.75 kW	150 A

Note: current draw stays the same across the rows because kVA sets the current, not the load's power factor. PF only affects how much real work (kW) the load does per amp drawn.

Sizing a load against a source. If you are feeding this load from a UPS, generator, or transformer, check the load against both the source's kVA rating AND the source's kW rating. Those are two independent numbers published by the manufacturer. A 10 kVA / 8 kW generator, for example, can supply up to 10 kVA of apparent power AND up to 8 kW of real power, whichever limit is reached first. Do not use the kW figures above as a substitute for the source's published kW rating.

Circuit Sizing: Starting Points

The numbers below are rough order-of-magnitude starting points under typical assumptions (copper conductors, 75°C terminations, short run, no ambient or bundling derates, non-continuous duty). They are not install specs. Actual breaker and wire selection depends on the equipment nameplate, conductor and termination temperature ratings, cable type, run length and voltage-drop target, ambient and bundling conditions, whether the load is continuous, any NEC 430/440 motor or HVAC provisions, and local code.

	Single Phase
Current draw (at full kVA)	150 A
Ballpark branch OCP	~150A

For a real install, run the full wire-size calculator with your actual run length, voltage, and drop target, and verify breaker selection against the equipment nameplate and local code.

Energy Cost at Full Load

A load with an apparent power of 15 kVA at load PF 0.85 draws 12.75 kW of real power. Running cost at that draw: $2.17/hour at $0.17/kWh (rates last reviewed April 2026), or $520.20/month (8h/day). Full breakdown.

kW Equivalent

15 kVA at PF 0.85 = 12.75 kW. See 12.75 kW to amps at 100V.

Other kVA Ratings at 100V

kVA	Single Phase Amps	Real Power (PF 0.8)
1 kVA	10 A	0.8 kW
2 kVA	20 A	1.6 kW
3 kVA	30 A	2.4 kW
5 kVA	50 A	4 kW
7.5 kVA	75 A	6 kW
10 kVA	100 A	8 kW
15 kVA	150 A	12 kW
20 kVA	200 A	16 kW
25 kVA	250 A	20 kW
30 kVA	300 A	24 kW
40 kVA	400 A	32 kW
50 kVA	500 A	40 kW

Frequently Asked Questions

How many amps is 15 kVA at 100V?expand_more

15 kVA at 100V is 150 amps (single-phase). 100V is a single-phase voltage; three-phase configurations are not typical at this voltage.

What is the difference between kVA and kW?expand_more

kVA is apparent power (V×I), which sets the current on the circuit and the sizing of conductors, breakers, and windings. kW is real power (the portion that does useful work), equal to kVA×load PF. A load with an apparent power of 15 kVA at load PF 0.8 draws 12 kW of real power. For a source such as a generator or UPS, kVA and kW are two independent manufacturer ratings, not two views of the same spec, and both have to be checked when sizing a load.

What size breaker would I need for 15 kVA at 100V?expand_more

This is a sizing question, not a conversion question, and there is no single answer from a page like this. Breaker selection depends on the equipment nameplate FLA, whether the load is continuous (NEC 210.19(A) applies the 125% continuous-load rule), conductor ampacity and termination temperature, any NEC 430/440 motor or HVAC provisions, and local code. The current draw on this page is the input to that sizing process, not the output. Verify against the equipment nameplate and a licensed electrician.

What size generator do I need for my loads?expand_more

Generator sizing is not a single-formula calculation. A rough napkin pass is: add up the steady-state watts of everything you plan to run, divide by a planning power factor (often 0.8 but not universal), and add margin. Then cross-check the result against the generator's published kW rating, which is a separate manufacturer spec set by the engine (prime mover) and is not derived from the generator's kVA rating by any formula. The caveats that matter for a real install: motor and compressor inrush can be several times steady-state current, load diversity and sequencing affect peak demand, voltage-dip tolerance of sensitive equipment limits how much motor load a given genset can start, and altitude and ambient temperature both derate output. A load with an apparent power of 15 kVA at PF 0.8 has a real-power draw of 12 kW, but that number alone is not sufficient to size a generator for a real installation.

Can a 15 kVA generator run my whole house?expand_more

A 15 kVA unit can cover most residential loads but often struggles with central AC plus other large appliances running simultaneously. Capacity depends on inrush from compressors and motors, load sequencing, and any transfer-switch load management. An electrician can run a load calc to confirm.

This calculator provides estimates for reference purposes only. Always consult a licensed electrician and verify compliance with the National Electrical Code (NEC) and local electrical codes before performing any electrical work.