Used Diesel Fuel Generators & Natural Gas Fuel Generators for Sale


Diesel and natural gas fuel generators are industrial power generation systems designed to provide reliable electricity for primary, standby, or backup applications. These generators convert fuel into electrical energy to support critical operations in facilities where power continuity is essential. Used diesel fuel generators and natural gas fuel generators are widely used in manufacturing, oil and gas, healthcare, data centers, and commercial operations requiring dependable on-site power. Browse available inventory below to find generator systems that meet your power output and operational requirements.

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Stock No.:

40958029

Used Onan 250 kW Natural Gas Generator | Model 250GEBC | Cummins G1A855G3 Engine | 480V | 570 Hours (2005)

Used- Onan 250kW Generator Model #: 250GEBC RPM: 1800 Year: 2005 Engine # 25302574 Engine Model# G1A855G3 Phase: 3 Volts: 480 HZ: 60 Hours: 570 Natural Gas. Built in 2005, this generator operates at 1800 RPM and supports a three-phase electrical system. It delivers a voltage output of 480 volts at a frequency of 60 Hz, making it suitable for various heavy-duty tasks and ensuring efficient energy distribution across demanding environments. Driven by a Cummins Engine, Model G1A855G3, Serial# 25302574.

MFR: Onan

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Stock No.:

54543001

Used Generac MG0300 300 kW Natural Gas Generator – 277/480V Enclosed Genset with 160 Reported Hours

Used Generac Natural Gas Generator, Model MG0300. 300 KW. Enclosed OH0924 Engine. Weather Enclosure. Eaton Inline 630 Amp Breaker. Coolant Heater. Built 2012. 3/60/277/480V. 160 hours Reported. Serial# 2114542.

MFR: Generac

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Stock No.:

54380001

Blue Star VD300-01 300 kW Diesel Generator – 480/277V Standby Power Unit

Used Blue Star Power Systems / Volvo 300 kW Standby (275 kW prime) Diesel Generator Set, Model VD300-1, SN-103448-1-1. Volvo Penta TAD1351GE engine rated 456 HP at 1800 RPM, SN-2013746570, EPA Tier 3 emissions. 3/60/277/480V, 12 lead reconnectable to other voltages. 400 Amp main-line circuit breaker. PMG - permanent magnet generator. UL listed stationary engine generator assembly. Basler DGC - 2020 digital control panel. Coolant heater. Weather enclosure. UL listed sub-base fuel tank with secondary containment. 121.4 Hrs. Yr 2018.

MFR: Blue Star Power Systems

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Stock No.:

51825001

Onan 35 kW Natural Gas Generator Set: Reliable Standby Power Solution

Used- Cummins / Onan 35 kW Standby Natural Gas Generator Set, Model 35SJB, SN-L900363017. Chrysler model H135 engine, SN-K1142033, 3600rpm. Rated 35 kW, 3/60/277/480V 12 lead reconnectable to other voltages.. 60 Amp main-line circuit breaker. Hours 403. No enclosure.

MFR: Cummins/Onan

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Stock No.:

54386001

Used Generac SD350 Diesel Generator – 350 kW / 438 kVA with 2,000 Gallon Base Tank, Only 275 Hours

Used- Generac Diesel Generator, Model SD350. Rated 350kW, 438KVA. Weather Enclosure. Iveco/FPT engine power: 530 HP @1,800 RPM. 3/60/277/480V. Includes 2,000 gallon base tank. 275.4 hours, Serial# 7855510, Built 2013. Includes Square D Company 500 kVa transformer for 120V usage.

MFR: Generac

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Stock No.:

54551001

Used-Caterpillar Diesel Generator Set, Model D3506C. Rated 350 kW. With enclosure and fuel tank. 1800 RPM. 3/60/480V. Built 2020. 779 hours.

MFR: Caterpillar

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Stock No.:

54292001

Buy Used Generac 350kW Standby Generator – 800A Breaker, Only 277 Hours

Used Generac 350 kW Standby Diesel Generator Set, Model SD0350-G36160D18GPSY, Mitsubishi 16L engine rated at 1800 RPM, Serial# 0A8829. Unit configured for 3/60/120/208V, 12 lead reconnectable to other voltages. 800 Amp main-line circuit breaker. Generac digital control panel. 24 Volt DC Battery Charger. Sound attenuated enclosure. 706 gallon UL listed sub-base fuel tank with secondary containment. 277 Hours. Serial# 2089404, Built 2006. Overall dimensions 200"L x 58"W x 118"T.

MFR: Generac

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Stock No.:

44430014

Used Cummins 350 kW Diesel Generator | Only 17 Hours | DFCC Package | NTA855G3 Engine | Built 1999

Used- Cummins Diesel Generator rated at 350 kW, built in 1999 with 17 hours. Package information: Cummins DFCC-3387631 ser no. A000055536. Engine information: Cummins NTA855G3 ser no. 30363796.

MFR: Cummins

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Stock No.:

40958023

Unused Caterpillar 455 kW Standby Generator Set – CAT C18 Engine

Unused- Caterpillar 455 kW Standby Generator Set. CAT C18 Engine. 1800 RPM. Control Panel. Open skid unit. 3/60/480 Volt.

MFR: Caterpillar

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Stock No.:

40958024

Caterpillar Model C18 455kW Industrial Generator

Unused- CAT 455Kw generator, Model 455. CAT Engine, model C18, Open skid unit.

MFR: Caterpillar

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Stock No.:

40958025

Unused Caterpillar 455 kW Standby Industrial Generator Set with CAT C18 Engine

Unused- Caterpillar 455 kW Standby Industrial Generator Set. CAT C18 Engine. 1800 RPM. Control Panel. Open skid unit. 3/60/480 Volt.

MFR: Caterpillar

Stock No.:

54607002

Used-Generac Diesel Generator, Model SD0500. Rated 500kW. 3 Phase, 277/480V. Daewoo Model P180LE engine. 792 hours.

MFR: Generac

Diesel and Natural Gas Generator Applications & Typical Use Cases

Used generators are deployed across industries where consistent and reliable power is required. Typical applications include:

  • Backup power for manufacturing plants and processing facilities

  • Prime power generation in remote or off-grid locations

  • Emergency power supply for hospitals, data centers, and critical infrastructure

  • Supporting oil and gas operations and field equipment

  • Providing temporary power for construction sites and industrial projects

When to Choose Diesel vs. Natural Gas Generators

The choice between diesel and natural gas generators depends on fuel availability, runtime requirements, and operational priorities. Diesel generators are often selected for their high power density, durability, and ability to handle variable loads. Natural gas generators are preferred in facilities with existing gas infrastructure, offering cleaner emissions and continuous fuel supply without the need for on-site storage.

Used Generator Buying Considerations

When evaluating a used diesel or natural gas generator, consider the following:

  • Power Rating (kW/kVA): Ensure output capacity matches load requirements

  • Fuel Type & Availability: Diesel vs. natural gas based on site infrastructure

  • Run Hours & Maintenance History: Indicator of wear and remaining service life

  • Voltage & Frequency Requirements: Compatibility with facility systems

  • Enclosure & Mobility: Skid-mounted, trailer-mounted, or enclosed units

  • Control Systems & Compliance: Monitoring capabilities and emissions requirements

Why Buy Used Diesel and Natural Gas Generators

Used generators provide a practical way to secure power generation capacity without the lead times associated with new units. Many systems are maintained as backup equipment and may have relatively low run hours. For facilities preparing for outages, expanding operations, or adding redundancy, used generators offer a dependable and cost-conscious solution.

Sell Your Used Diesel Fuel and Natural Gas Generators

If you are rotating out backup units or downsizing power capacity, Aaron Equipment can help reposition surplus generators within active resale channels. We work with sellers to evaluate equipment and connect it with buyers seeking reliable power systems for industrial and commercial use.

A diesel or natural gas generator is a power generation system that converts fuel into electricity using an internal combustion engine. These generators are used for backup, standby, or primary power in industrial and commercial applications.

They are used to provide reliable power for facilities during outages, in remote locations, or as part of continuous operations. Common applications include manufacturing, healthcare, data centers, and energy production environments.

Diesel generators typically offer higher power density and are well-suited for backup or variable load applications. Natural gas generators provide cleaner emissions and are often used where a continuous fuel supply is available through existing gas infrastructure.

Costs vary based on power rating, fuel type, run hours, manufacturer, and overall condition. Higher-capacity or low-hour units generally carry greater value, especially when configured for industrial or critical power applications.

Yes. Aaron Equipment purchases used diesel and natural gas generators. Our team can review system details and help facilitate resale or direct purchase opportunities.

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