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Wärtsilä 20V31SG

31SG

In Production

Wärtsilä 20V31SG — 649.1 L V20 four-stroke lean-burn spark-ignited gas engine generating set (Wärtsilä 31SG), for power plants. 11779 kWe at 750 rpm / 50 Hz, 11377 kWe at 720 rpm / 60 Hz; electrical efficiency 51.5%.

Wärtsilä 20V31SG 649.1L V20 natural gas generator engine — 14,724 kVA prime specifications
Wärtsilä 20V31SG 649.1L V20 natural gas generator engine — 14,724 kVA prime specifications
Prime Power · 50 Hz
14,724 kVA
Electrical Output
11,779 kWe
Cylinders
V20
Displacement
649.1 L
Rated Speed
750 / 900 RPM

Power Ratings

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

50 Hz750 RPM

kWmkWekVA
Prime Power1177914723.8

60 Hz900 RPM

kWmkWekVA
Prime Power1137714221.3

Wärtsilä 20V31SG generator set context

The Wärtsilä 20V31SG is listed here as a natural gas generator-drive engine for 50 Hz and 60 Hz generator sets, with a headline 14,724 kVA / 11,779 kWe / prime 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

20v31sgWärtsilä 20V31SG

Technical Specifications

BrandWärtsilä
Model20V31SG
Series31SG
ConfigurationV20
Cylinders20
Displacement649.1 L
Fuel TypeNatural Gas
Ignition TypeSpark Ignition
Cooling MethodLiquid-Cooled
Emissions StandardUnregulated
Country of OriginFinland

Frequently asked questions

What is the power output of the Wärtsilä 20V31SG?

The Wärtsilä 20V31SG is rated at 14,724 kVA prime at 50 Hz (750 rpm); and 14,221 kVA prime at 60 Hz (900 rpm).

Does the 20V31SG run at 50 Hz or 60 Hz?

The Wärtsilä 20V31SG is available for both 50 Hz (750 rpm) and 60 Hz (900 rpm).

What fuel does the Wärtsilä 20V31SG use?

The Wärtsilä 20V31SG is a Natural Gas generator-set engine.

What is the displacement and cylinder configuration of the 20V31SG?

The Wärtsilä 20V31SG is a V20 (20-cylinder) engine with a displacement of 649.1 L.

Is the Wärtsilä 20V31SG still in production?

Yes — the Wärtsilä 20V31SG is a current production model.

Is a datasheet available for the 20V31SG?

Yes — an official Wärtsilä datasheet for the Wärtsilä 20V31SG can be downloaded from this page.

Compare Wärtsilä 20V31SG

Reference

Last database update
2026-06-08
Manufacturer files
1 datasheet linked

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