Used Natural Gas Generators For Sale

Natural gas generators run on pipeline gas, associated gas, LPG or LNG, while diesel generators run on distillate fuel. Gas engines cost considerably less to run wherever gas is available, produce lower NOx and particulate emissions, and require no on-site fuel storage or delivery logistics. Diesel generators start faster from cold, cost less to buy per kW, and remain the right choice where no gas supply exists. For continuous-duty operation above roughly 4,000 hours a year, gas almost always wins on total cost of ownership.

A natural gas generator uses a spark-ignited reciprocating engine, mechanically similar to a large petrol engine, coupled to a synchronous alternator. Gas and air are mixed, compressed in the cylinder, ignited by a spark plug, and the resulting combustion drives the piston. The crankshaft turns the alternator at 1,500 rpm for 50 Hz output or 1,800 rpm for 60 Hz. Most industrial units run lean-burn, using excess air to lower combustion temperature and reduce NOx formation.

Modern industrial gas engines achieve 44% to 46% electrical efficiency at full load. Caterpillar publishes 44.6% for the G3512H, 45.0% for the G3516H and 45.0% for the G3520H. Jenbacher publishes up to 45.8% for the J620. In combined heat and power configuration, recovering jacket water and exhaust heat, total plant efficiency reaches 85% to 90%. By comparison, a simple-cycle gas turbine of similar output typically achieves 30% to 38%.

INNIO Jenbacher (Type 3 J320, Type 4 J420 and JGS 420, Type 6 J620, JGS 620 and JMS 620), Caterpillar (G3512H, G3516, G3516 LE, G3516C, G3516H, G3520C, G3520E, G3520H, G3612), MWM (TCG 2020 V12, V16 and V20, TCG 2032 V16, TCG 3016 V16, TCG 3020 V20), Waukesha (16V150LTD, VHP L9394GSI) and Deutz (TCG 2020 V20, TBG 620 V16). Stock spans model years from the late 1990s to the current year and include new surplus, low-hour used and refurbished units.

Yes. Current listings include Caterpillar G3516, G3516 LE, G3516C, G3520H, XQ1475G, 3508B and 3516C gas sets, plus CG170B-20 and CG260-16 units, from 0.65 MW to 4.3 MW at 50 Hz or 60 Hz. Each listing shows the stock number, year, frequency and rating. Stock changes often, so confirm availability before you plan around a unit.

The price of a natural gas generator depends on its output and duty rating, whether it is new, used or refurbished, its hours since overhaul, the brand and model, the frequency, voltage and emissions build, and what is included in the scope of supply. Installation, gas treatment and balance of plant are often a large share of the total. Each USP&E listing shows its asking price or “Price on request”, and USP&E quotes the delivered scope for your site.

USP&E lists used, new and refurbished Cat gas gensets from 0.65 MW to 4.3 MW, including the G3516, G3516 LE, G3516C, G3520H, XQ1475G, CG170B-20 and CG260-16. Each listing shows the stock number, year, frequency and rating. USP&E is not affiliated with Caterpillar Inc.

For the high-efficiency H-series, Caterpillar publishes 1,505 ekW for the G3512H, 2,007 ekW for the G3516H and 2,500 ekW for the G3520H. Larger G3600 units such as the G3612 sit above that. Multi-unit plants are built by running several sets in parallel, so total plant size is set by the number of units.

No. USP&E is an independent seller and is not affiliated with Caterpillar Inc. Every Cat natural gas generator listed is a unit we can inspect, test and ship. Ask for the documentation and inspection report on any unit before you buy.

Check running hours and the hours since the last overhaul, the maintenance records, and whether the engine suits your gas quality. Confirm the frequency, voltage and emissions your permit requires, then the controls, switchgear and heat recovery included. A load test and an oil analysis show the set’s condition better than its age alone.

Yes, and they are increasingly the preferred option where grid connection queues run to several years. Fast-start gas engines reach full load in under two minutes and handle the step loads that IT equipment produces. Modular multi-unit arrays give N+1 redundancy at far lower cost than duplicating a single large machine, and permit capacity to be added as the campus grows. USP&E supplies the gensets, switchgear, gas treatment and heat recovery, plus EPC and O&M.

Individual units from 1 MW to around 4.5 MW, and multi-unit packages above 50 MW. Multi-unit plants scale beyond 100 MW using common switchgear and synchronising controls. The 1.5 MW to 2.5 MW band is the volume segment for mining and industrial captive power; the 2.5 MW to 4.5 MW band suits utility-scale IPP projects.

In industrial and utility power, a large gas generator is usually a reciprocating gas engine set of 2.5 MW to 4.5 MW per unit, such as the Jenbacher J620, Caterpillar G3612 or CG260, or MWM TCG 2032. Plants above that size run several units in parallel on common switchgear, which can scale beyond 100 MW.

It varies by listing. Some units are sold as the engine and alternator only; others include the control panel, gas train, radiator, exhaust, enclosure or container. Confirm the scope in writing, and ask whether inspection, load testing, shipping and installation are quoted separately.

Many can, with the correct configuration. Jenbacher and Waukesha engines in particular are designed to tolerate biogas, landfill gas, sewage gas, coal mine gas, flare gas and wellhead gas. The determining factor is methane number: gases rich in heavier hydrocarbons lower it and raise knock risk, requiring ignition retard and derating. The Caterpillar G3520H additionally supports up to 25% hydrogen blending by volume. Always match the engine specification to an actual gas analysis before purchase.

A well-maintained industrial gas engine runs 60,000 to 80,000 hours before a major overhaul, with top-end overhauls at roughly 20,000 to 30,000 hour intervals depending on platform and duty. With scheduled major overhauls, total service life commonly exceeds 200,000 hours, which is twenty years or more of continuous operation. Maintenance discipline and gas quality matter far more to engine life than calendar age, which is why documented service history is the most important thing to check when buying used.

Yes, both in-house. EPC scope covers feasibility, gas supply assessment, civil works, gas treatment, installation, MV switchgear, grid interconnection, heat recovery, commissioning and compliance testing. O&M scope covers operator staffing and training, scheduled maintenance to OEM intervals, overhauls, spares holding, condition monitoring and availability guarantees. Typical EPC delivery for a 10 MW to 30 MW gas plant is 9 to 14 months from notice to proceed.