Caterpillar Introduces New G3520C Natural Gas Generator Sets for Island Mode Operation

Caterpillar Inc. today announces the introduction of two G3520C natural gas generator sets now available with optional air and fuel system controls that have been enhanced to provide superior island mode operational capability. Designed for commercial and institutional customers that require exceptionally reliable, high-quality electric power, the island mode control system option for the G3520C gas generator sets, offered in 60 Hz and 50 Hz versions, allows customers to generate power independently from the power grid with a high-efficiency, natural gas-fueled engine.

"Distributed generation is widely recognized as one effective way to use energy more efficiently, but in many applications which can only withstand limited deviations in frequency and voltage during loading, unloading and load fluctuation, the transient response capability and the steady state stability become critical," said Rob Schueffner, Marketing Manager in Caterpillar's Electric Power Division. "The introduction of the G3520C gas generator set with the island mode feature fills a critical need while contributing to the reduction of Greenhouse Gas (GHG) emissions by creating more opportunities for gas generator sets in distributed generation applications."

The Cat natural gas generator sets with the island mode feature tackle the major barriers for distributed generation in stand-alone applications where a utility grid connection is unavailable or the utility grid is not stable. The improved transient capability also supports the use of low-emission gas generator sets in standby power applications, providing customers with more clean energy options for their electric power supply solutions.

Driven by an electronically controlled, lean-burn gaseous-fueled reciprocating Cat engine, the G3520C generator set was designed to offer a high power density and excellent fuel efficiency while maintaining tight NOx control. It provides the flexibility to operate on pipeline natural gas with a wide range of Caterpillar Methane Numbers (MN) and delivers an industry-leading ISO electrical efficiency of up to 38.4 percent at 60 Hz and up to 40.4 percent at 50 Hz - even with the use of two engine-driven water pumps.

The Cat G3520C generator set operates at 60 Hz/1800 rpm with a continuous rating of 2055 ekW, or at 50 Hz/1500 rpm with a continuous rating of 1966 ekW. It has a standard NOx emissions rating of 1g/bhp-hr at 60 Hz and 500mg/NM3 at 50 Hz, with performance of 0.5g/bhp-hr at 60 Hz and 250mg/NM3 at 50 Hz available through a 54° C separate circuit aftercooler (SCAC) system that can be used with a conventional cooling system arrangement in almost all geographic locations. The G3520C is built on a heavy-duty, diesel-based, bottom-end platform for superior durability with a unique top-end design for gas application optimization. It also features an open combustion chamber design capable of operating at pressures as low as 1.5 psi (10.3 kPa).

Standard on the G3520C generator set is a digital microprocessor Gas Engine Control Module, which automatically and precisely regulates ignition, engine governing and air-to-fuel ratio for optimum fuel economy. Its patent pending, technologically-advanced air-to-fuel ratio control monitors charge air density and maintains stringent NOx control under a variety of ambient and load conditions. The G3520C generator set features an individual-cylinder detonation sensing and timing control, with a prechamber-type spark plug design for extended service life without adjustment.

The Cat G3520C generator set is easily tailored to specific applications with a wide selection of Cat SR4B generators and generator set attachments, including oversized generators. Additional features include exhaust options, circuit breakers, alarm and remote annunciator modules, and battery chargers.

Caterpillar is helping to lead the power generation marketplace with power systems engineered to deliver unmatched flexibility, expandability, reliability and cost-effectiveness. The company offers worldwide product support, with parts and service available globally through the Caterpillar service and dealer network. In addition, dealer service technicians are trained to service every aspect of Cat equipment.

For more than 80 years, Caterpillar Inc. has been making progress possible and driving positive and sustainable change on every continent. With 2007 sales and revenues of $44.958 billion, Caterpillar is the world's leading manufacturer of construction and mining equipment, diesel and natural gas engines, and industrial gas turbines.

For more information on Cat generator sets and continuous power systems, or to find the local Cat dealer nearest you, please visit us on the web at http://www.cat-electricpower.com/ or e-mail cat_power@cat.com. For a specification sheet on the Cat G3520C gas generator set, visit http://go.cateps.com/pr.