500kW generators at a glance

• Rated 500kW (625kVA) standby, typically about 450kW prime
• 752 amps at 480V, three-phase, the most common voltage at this size
• Burns about 26.4 gallons of diesel an hour at three-quarter load
• Sized for large sites like a manufacturing plant, a hospital wing, a mid-sized data center or a water treatment plant
• 60Hz units built for North American power
• New and used units in stock, shipping from Colorado, Florida and Texas

500kW generators in stock now

The go-to size for large commercial and industrial sites

A 500kW generator carries serious load. It’ll run a manufacturing plant’s production lines, a hospital wing with its imaging and critical care, a mid-sized data center and its cooling, or the pumps at a water or wastewater plant. Many facilities run one as their main standby set, and larger campuses parallel two or more for redundancy.

Our 500kW stock changes week to week. It usually runs from brand-new units to used standby sets from CAT, Cummins, Generac, Kohler and others, mostly diesel with some natural gas.

Every unit is ours. We buy and own our inventory outright, so we can tell you where a generator came from, how it was used and what our technicians found when they went over it. Units ship from our yards in Brighton, Jacksonville, Pensacola and Austin, and we can get them to a site anywhere in the contiguous US, with Canada and Mexico on request.

Not sure 500kW is the right fit? Run your loads through our generator sizing calculator, or call and talk it through with someone who sizes these every day.

What a 500kW generator can power

Nearly every 500kW generator is three-phase, and most run at 480V. Typical buyers include:

• Manufacturing and industrial: production lines, air compressors, welders and fabrication equipment, and process pumps
• Healthcare: hospital wings and large medical centers, including operating rooms, ICUs and imaging equipment like MRI and CT scanners
• Data centers and IT: server rooms, UPS systems and the cooling that keeps them running
• Water and municipal: water and wastewater treatment plants, lift stations, emergency operations centers, and police and fire stations
• Commercial buildings: multi-story offices with HVAC and elevators, hotels and resorts, and large grocery and retail stores

Size for starting loads, not just running loads. Chillers, large pumps, compressors and elevators pull several times their running current for a moment when they start, and that’s usually what decides whether 500kW is enough. A good load assessment also covers which circuits you can shed during an outage and how much room you want for future growth.

500kW generator specs

A 500kW standby generator is rated at 625kVA. Amps are three-phase at a 0.8 power factor, from our kVA, kW and amperage chart. Most 500kW sets are 480V; 208V and 240V are uncommon at this size.

Voltage (three-phase)	Amps
208V	1,735
240V	1,504
480V	752
600V	601

Fuel use below is estimated from our fuel consumption charts. Actual use depends on the engine and site conditions.

Load	Diesel (gal/hr)	Natural gas (ft³/hr)
1/4	11.0	2,276
1/2	18.5	3,687
3/4	26.4	5,096
Full	35.7	6,407

How 500kW compares with nearby sizes

Size	kVA	Amps at 208V	Amps at 480V	Diesel at 3/4 load (gal/hr)
400kW	500	1,388	601	21.3
500kW	625	1,735	752	26.4
600kW	750	2,082	902	31.5
750kW	938	2,602	1,128	39.3

500kW spec sheet library

Spec sheets for the 500kW models we see most often. Details can change by model year, so check the sheet against the nameplate on the exact unit you’re quoting. Need one that isn’t here? Ask and we’ll find it.

Brand	Model	Fuel	Spec sheet
Baldor	IDLC500	Diesel	Baldor IDLC500 spec sheet (PDF)
CAT	C15 500kW, Tier 4 Interim	Diesel	CAT C15 500kW spec sheet (PDF)
Generac	SD500	Diesel	Generac SD500 spec sheet (PDF)
Generac	MD500	Diesel	Generac MD500 spec sheet (PDF)
Generac	SG500	Natural gas	Generac SG500 spec sheet (PDF)
Generac	MG500	Natural gas	Generac MG500 spec sheet (PDF)
Kohler	500REOZJB	Diesel	Kohler 500REOZJB spec sheet (PDF)
Kohler	500REOZVB	Diesel	Kohler 500REOZVB spec sheet (PDF)
Kohler	500REOZVC	Diesel	Kohler 500REOZVC spec sheet (PDF)
Multiquip	CG500C2	Diesel	Multiquip CG500C2 spec sheet (PDF)
Multiquip	EGC-500C	Diesel	Multiquip EGC-500C spec sheet (PDF)
Multiquip	EGC500DD	Diesel	Multiquip EGC500DD spec sheet (PDF)

Browse every size in our full spec sheet library.

What’s included when you buy from us

• An inspection by our EGSA-certified technicians before the unit leaves our yard
• Load bank testing available, so you can see it carry a load before it ships
• Shipping to your site anywhere in the contiguous US, with Canada and Mexico on request
• Photos, the spec sheet and a walkaround video of the actual unit
• A deposit that holds your unit while you finalize, with a clear quote expiration date
• Service after the sale from our teams in Colorado, Florida and Texas

Watch our load bank testing

Before a unit ships we can put it on a load bank so you can see it carry load. Our YouTube channel has load bank runs on generators across the size range.

500kW generator FAQ

How many amps does a 500kW generator put out? At three-phase and a 0.8 power factor, a 500kW generator delivers about 752 amps at 480V, 601 amps at 600V, 1,504 amps at 240V and 1,735 amps at 208V. Your electrician will size the breaker and transfer switch from those numbers.

How much fuel does a 500kW generator use? A diesel 500kW unit burns roughly 18.5 gallons an hour at half load and 35.7 at full load. At three-quarter load that’s about 634 gallons over 24 hours, so plan your tank around the runtime you need. On natural gas, figure about 3,687 cubic feet an hour at half load and 6,407 at full load, and confirm your gas supply can deliver that volume and pressure.

Is a 500kW generator the same as 625kVA? Yes. Generators are usually rated at a 0.8 power factor, so 500kW of real power equals 625kVA. You’ll see both numbers on spec sheets and nameplates.

What’s the difference between a standby and a prime rating? A standby rating is for backup power during outages. A prime rating is for running as the main power source for long stretches, and it’s often around 10% lower, so a 500kW standby set may carry about 450kW prime. Check the spec sheet for each unit.

Can two smaller generators do the job of one 500kW unit? Yes. Two 250kW units paralleled through switchgear can share a 500kW load and give you redundancy if one goes down for service. The trade-off is the cost and complexity of the paralleling controls. We can help you compare both setups.

Should I buy new or used? Used units cost less and are often ready to ship now, while new units can carry a factory lead time. We stock both. Every used unit lists its hours and year, and we’ll send photos and a walkaround video of the actual generator before you commit.

How much does a 500kW generator cost? Price depends on whether it’s new or used, its hours, brand, fuel type and enclosure. Tell us about your site and we’ll send pricing on every 500kW unit that fits.

Can I rent a 500kW generator instead? Yes. Our rental teams in Colorado, Florida and Texas can set you up for a short-term job, an event or while you wait on a permanent unit. See generator rentals.

Get pricing on a 500kW generator

Tell us what you’re powering and when you need it, and we’ll send pricing on every 500kW unit that fits. Call 877-866-6895, text us for a quote or request one online. Want to see the unit first? Ask for a walkaround video.