SettingsSettings for this calculationUS
The apparent power rating in kilovolt-amperes.
The kVA figure on a generator, a transformer or a supply agreement. It describes how much current the equipment can carry at its voltage, whether or not that current does any work; the power factor below says how much of it does.
The ratio of real to apparent power: 1 for a heater, about 0.8 to 0.9 for a loaded three-phase motor. It opens on 0.8, the factor three-phase generator sets are rated at; a single-phase set is rated at 1.
Leave 0.8 in place to convert a three-phase generator's own kVA badge, and enter 1 for a single-phase set. Three-phase generator sets are conventionally rated at 0.8 — Cummins lists the C20D6 at 25 kVA and 20 kWe — while single-phase sets are rated at 1, where kVA and kW are the same number. For a load, take its power factor from the nameplate or a power-quality meter: resistive heating is 1, three-phase induction motors run about 0.8 to 0.9 at full load and fall well below that lightly loaded, a small single-phase motor can sit far lower even at full load, and modern electronics with correction sit close to 1.
Real power
80 kW
kW = kVA × power factor. The kVA, kW and kvar are the three sides of the power triangle; the kvar is the part of the current that flows without doing work, which is what correction equipment cancels. The result scales directly with the power factor entered.
- Power factor applied
- 0.8
- Reactive power, kVA × √(1 − PF²)
- 60 kvar
They open the calculator with your figures already in it
kVA to kW Calculator: 80 kW — shown in imperial, US market. The link sets both, so the result they see is the one on your screen.
Show calculation logicHide calculation logic
How this was calculated
Formula source(s)
- Real power = apparent power x power factor; kW = kVA x PF, and the reactive part is kVA x √(1 − PF²)
- Cummins Inc., 2022 Global Product Guide — Power Generation Products (GLM-5763-EN): the diesel sets are listed with their kWe at 0.8 of their kVA (the C20D6 at 25 kVA and 20 kWe standby, the C30D6 at 37.5 kVA and 30 kWe), the three-phase convention the opening 0.8 follows; the single-phase sets are listed in kW with a current that is the kW divided by the volts, so their kVA and kW are the same number (the RV QG 2800 at 2.8 kW and 23.3 A on 120 V, the RV QG 2300 at 2.3 kW and 10 A on 230 V, the QD5000 at 4.8 kW and 21 A on 230 V)
- Cummins Inc., Pre-Configured Diesel generator sets, specification sheet NAS-6437-EN (12/19): the C20 D6 set for 120/240 V, 1 phase, is 20 kW and 20 kVA standby at 60 Hz — the model the 2022 guide lists at 25 kVA and 20 kWe
Inputs used
- Apparent power (kVA)
- 100
- Power factor
- 0.8
Intermediate steps
- Power factor applied
- 0.8
- Reactive power, kVA × √(1 − PF²)
- 60 kvar
Confidence note: kW = kVA × power factor. The kVA, kW and kvar are the three sides of the power triangle; the kvar is the part of the current that flows without doing work, which is what correction equipment cancels. The result scales directly with the power factor entered.
What this calculation does not cover
- The answer is only as right as the power factor entered. Three-phase generator sets are conventionally rated at 0.8 — Cummins lists the C20D6 at 25 kVA and 20 kWe — while single-phase sets are rated at 1, where kVA and kW are the same number. The field opens on the three-phase figure, not because any installation runs at it: a motor-heavy site runs lower and a corrected or largely resistive one higher, and the kW figure moves in direct proportion with whatever goes in the box.
- This is a rating conversion, not a load calculation. It does not establish connected load or maximum demand, apply diversity or demand factors, or size a supply, cable or protective device. Those remain separate calculations under the wiring regulations in force for the job.
- Steady state only. Motor starting current can be several times the running figure, and on a generator that transient frequently determines the set size rather than anything this conversion produces.
- A single power factor covers displacement only. Non-linear loads such as variable-speed drives, switch-mode supplies and some LED drivers draw distorted current, so the true power factor sits below the displacement figure and the supply carries more apparent power than one number suggests.
- Nameplate kVA is quoted at the manufacturer's reference conditions. Altitude, ambient temperature and duty rating all reduce what a generator or transformer can actually deliver on site, and none of that derating is in this conversion.
Add the equipment this sizes
This result is a specification — 80 kW — not a quantity. Put the thing it sizes into your project: how many, what you call it, and your supplier’s price.
Computed in your browser — nothing you enter is uploaded. Presented in US customary units and US trade terminology. Where a formula follows a published standard, that standard and its edition are cited beside it on this page; where none governs, the page says so. Local amendments override model codes — verify against the code in force where you build.
Sources checked 2026-10-05 · v1.1.0
Regulatory standards & verification citations3
- Real power = apparent power x power factor; kW = kVA x PF, and the reactive part is kVA x √(1 − PF²)
- Cummins Inc., 2022 Global Product Guide — Power Generation Products (GLM-5763-EN): the diesel sets are listed with their kWe at 0.8 of their kVA (the C20D6 at 25 kVA and 20 kWe standby, the C30D6 at 37.5 kVA and 30 kWe), the three-phase convention the opening 0.8 follows; the single-phase sets are listed in kW with a current that is the kW divided by the volts, so their kVA and kW are the same number (the RV QG 2800 at 2.8 kW and 23.3 A on 120 V, the RV QG 2300 at 2.3 kW and 10 A on 230 V, the QD5000 at 4.8 kW and 21 A on 230 V)
- Cummins Inc., Pre-Configured Diesel generator sets, specification sheet NAS-6437-EN (12/19): the C20 D6 set for 120/240 V, 1 phase, is 20 kW and 20 kVA standby at 60 Hz — the model the 2022 guide lists at 25 kVA and 20 kWe
Cite this page
Your workspace
Most jobs need more than one number. Add the calculators you need next and they open right here, underneath this one — your figures stay on screen and nothing is lost to a page change.
Generators, transformers and supply capacities are rated in kVA while the work they do is measured in kW, and the gap between the two is the power factor. The field opens on 0.8, the factor three-phase sets are conventionally badged at, so a three-phase generator's own rating converts as it stands; a single-phase set is rated at 1, where its kVA and kW are the same number; for a load, the power factor comes off its nameplate or a meter, and a motor-heavy site sits lower while a corrected or largely resistive one sits higher. The point most often missed is that generator sets carry both ratings for a reason. The kVA figure describes the alternator and the kW figure the engine, so a load with a poor power factor can saturate the alternator while the engine still has headroom, which is why sizing on kW alone leads to trouble.