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Caterpillar CG18

CG

In Production

Caterpillar CG18 is an 18.1 L inline-6 turbocharged and air-to-air aftercooled natural-gas engine for 60 Hz generator sets. The official Cat DG500 specification lists 500 kWe standby at 1800 RPM and EPA stationary emergency and non-emergency compliance; EPA annual certification data lists 567 kWm.

Caterpillar CG18 18.1L L6 Turbocharged Air-to-Air Aftercooled natural gas generator engine — 625 kVA standby specifications
Caterpillar CG18 18.1L L6 Turbocharged Air-to-Air Aftercooled natural gas generator engine — 625 kVA standby specifications
Standby Power · 60 Hz
625 kVA
Electrical Output
500 kWe
Cylinders
L6
Displacement
18.1 L
Rated Speed
1,800 RPM

Power Ratings

kWm = mechanical shaft power · kWe = electrical output · kVA = kWe ÷ 0.8 pf

60 Hz1800 RPM

kWmkWekVA
Standby Power500625

Caterpillar CG18 generator set context

The Caterpillar CG18 is listed here as a natural gas generator-drive engine for 60 Hz generator sets, with a headline 625 kVA / 500 kWe / standby rating. Use this page to compare the published engine output, electrical kWe/kVA ratings, emissions level, datasheet availability, and neighboring models before specifying an alternator, controller, enclosure, voltage, and compliance package.

Also searched as

cg18Caterpillar CG18

Technical Specifications

BrandCaterpillar
ModelCG18
SeriesCG
ConfigurationL6 Turbocharged Air-to-Air Aftercooled
Cylinders6
Displacement18.1 L
Compression Ratio10.5:1
Fuel TypeNatural Gas
Ignition TypeSpark Ignition
Cooling MethodLiquid-Cooled
Emissions StandardU.S. EPA Stationary
CertificationsU.S. EPA Stationary Emergency, U.S. EPA Stationary Non-Emergency
Country of OriginUnited States

Frequently asked questions

What is the power output of the Caterpillar CG18?

The Caterpillar CG18 is rated at 625 kVA standby at 60 Hz (1,800 rpm).

Does the CG18 run at 50 Hz or 60 Hz?

The Caterpillar CG18 is rated for 60 Hz (1,800 rpm).

What fuel does the Caterpillar CG18 use?

The Caterpillar CG18 is a Natural Gas generator-set engine.

What is the displacement and cylinder configuration of the CG18?

The Caterpillar CG18 is an inline-6 (6-cylinder) engine with a displacement of 18.1 L.

What emissions standard does the CG18 meet?

The Caterpillar CG18 is certified to U.S. EPA Stationary emissions standards.

Is the Caterpillar CG18 still in production?

Yes — the Caterpillar CG18 is a current production model.

Is a datasheet available for the CG18?

Yes — an official Caterpillar datasheet for the Caterpillar CG18 can be downloaded from this page.

Reference

Last database update
2026-07-25
Manufacturer files
1 datasheet linked

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