Generator Sets offer high efficiency and low emissions.
Press Release Summary:
Natural-gas-fueled Series G3500 generators, for extended-duty distributed generation service, are driven by reciprocating engines in 12-, 16-, and 20-cylinder configurations. Engines operate at 1500 rpm/50 hz, 1200 rpm/60 hz, or 1800 rpm/60 hz, with ratings up to 2.1 MW. They deliver up to 43.5% mechanical efficiency with NOx emissions of less than 0.5 g/bhp-hr and 250 mg/Nm³. Features include open-protocol, SCADA-compatible ADEM(TM) III digital microprocessor control.
Original Press Release:
New Cat® Advanced Natural-Gas-Fueled Generator Set Offers High Efficiency, Low Emissions, Low Electricity Cost in Distributed Generation Service
Peoria, ILL. - Caterpillar Inc. introduces the new Cat G3500 Series advanced natural-gas-fueled generator sets, designed to deliver electricity at the lowest cost per kilowatt-hour in extended-duty distributed generation service, in both island mode and grid parallel operations. The first unit in the series, the G3520C, will make its debut at POWER-GEN International 2002 in Orlando, Dec. 10-12, 2002.
The new G3500 Series generator sets are driven by Cat advanced lean-burn gas reciprocating engines in 12-, 16- and 20-cylinder configurations, operating at 1500 rpm/50 hz, 1200 rpm/60 hz or 1800 rpm/60 hz, with ratings up to 2.1 MW. They can deliver up to 43.5 percent mechanical efficiency with maintenance costs per kW-hr equal to or lower than for competing systems. NOx emissions are rated at less than 0.5 g/bhp-hr and 250 mg/Nm3 (1/2 TA Luft).
High power density - up to 105 kW per cylinder - means fewer generator sets are required for the same power demand; thus fewer interconnects, less ancillary equipment and reduced installation labor; resulting in overall lower first cost and quick return on investment.
Growth in DG
"This new generator set series fills an emerging need in the distributed generation market," sags Michael R. Devine, gas product marketing manager with the Electric Power Group of Caterpillar Inc. "Distributed generation is growing rapidly as utilities see its potential as a quick, low-risk wag to bolster power supplies and as a tool to stabilize voltage on local distribution systems.
"End users are also gravitating toward distributed generation as they see opportunities to increase their power reliability and operating efficiency, and turn increasingly competitive electric power markets to their advantage. "These trends are driving demand for generating systems that combine low emissions with attractive operating costs in applications involving extended annual hours of service. Generator sets driven by advanced natural-gas-fueled reciprocating engines are positioned to meet that need better than any other technology."
Growth in natural gas for power generation is driven largely by air-quality regulations. "Hs concerns rise about air pollution and global climate change, governments are steadily tightening emission limits on nitrous oxides (NOx) and other pollutants," Devine said. "That is a major reason why the U.S. Department of Energy projects that the natural gas share of the generation market will increase from 15 percent in 1999 to 32 percent in 2020."
Unique design
The new G3500 Series is designed to suit a wide range of distributed generation applications. Built on the heavy-duty diesel-based platform of their industry-proven predecessors, the new units are 5 to 25 percent lower in first-cost per kW for short-run peak shaving and dual-purpose standby installations. In longer-running base load, peaking and cogeneration service, they deliver electricity at lower cost per kilowatt-hour than other comparable-scale engine- and turbine-driven systems.
The new generator sets are designed to operate reliably and efficiently with minimal hands-on operator attention. The new G3500 Series is the only generator set line in the 2 MW class that uses an open combustion chamber design. Its low-pressure fuel system (1.5 to 5 psi/10 to 35 kPa) allows it to fit in the broadest range of distributed generation settings.
The new G3500 Series uses an ADEM(TM) III digital microprocessor control, which automatically and precisely regulates engine governing, air/fuel ratio and ignition, resulting in optimum fuel economy with stringent control over NOx emissions.
The ADEM III control lets the G3500 respond to block loading and unloading without significant changes in speed, thus minimizing frequency and voltage fluctuations. When a kilowatt sensor detects a block load, control software momentarily adjusts the air/fuel mixture to enable the generator set to respond smoothly and precisely. Similarly, when a block load drops offline, a control system compensates by bypassing compressed air and fuel from the aftercooler to the inlet side of the turbocharger. This reduces the air/fuel charge to the cylinders and significantly improves power quality during a block load drop transient. The new G3500 Series meets ISO 8528-5 standards for recovery time, voltage dip and frequency deviation for block loads up to 25 percent.
A technologically advanced air/fuel ratio control (patent pending) monitors charge air density and maintains NOx within tight tolerances under all ambient and load conditions. It is an active control system that is immune to changes in air temperature and humidity, and requires minimal maintenance and adjustment.
The open-protocol, SCADA-compatible ADEM III control provides integrated management of major functions and includes comprehensive safety shutdowns and self-diagnostics. The control module, environmentally sealed in a diecast aluminum housing, is immune to vibration, insulated against electrical noise, and accurate at temperatures from -40°F to 250°F (-40°C to 120°C).
Detonation sensors monitor each cylinder and automatically retard timing if detonation occurs. The G3500 also minimizes downtime for planned maintenance. A prechamber-type spark plug design delivers extended service life without adjustment. Lower NOx formation and lower oil temperatures reduce oil nitration and oxidation, enabling 40 to 50 percent longer oil-change intervals. Heavy-duty components allow long, continuous service between top-end and major overhauls.
For more information about the new G3500 Series or to find a Caterpillars dealer in your area, call Caterpillar at (800) 321-7332.
For more than 75 years, Caterpillar Inc. has been building the world, s infrastructure and, in partnership with Cat dealers, is driving positive and sustainable change on energy continent. With 2001 sales and revenues of $20.45 billion, Caterpillar is the world' s leading manufacturer of construction and mining equipment, diesel and natural gas engines and industrial gas turbines. The company is a technology leader in construction, transportation, mining, forestry, energy, logistics, financing and electric power generation. More information is available at www.cat-electricpower.com.
