Cogeneration CHP, Equipment & Technology, Europe

GE Jenbacher launches 9.5 MW, 48.7 per cent efficient J920 gas engine

By TIM PROBERT
GE Jenbacher has launched the J920 gas engine, a 9.5 MW unit with an electrical efficiency of 48.7 per cent, which the Austrian-based firm claims is the most efficient in its class.
GE Jenbacher says the electrical efficiency of the 20-cylinder J920 engine has been raised by 1.5 percentage points on the “industry standard” to 48.7 per cent largely due to the utilization of a two-stage turbocharging system. This technology was first used to raise the output of the J624, which to date was the largest Jenbacher gas engine, from 4 MW to 4.4 MW and to increase its electrical efficiency to 46.5 per cent.
The Austria-based company says it is targeting three main applications for the J920: independent power production; peak shaving/grid balancing for renewables; and for combined heat and power, for which it claims the J920 could achieve efficiency of around 90 per cent.
Speaking to Power Engineering International at the launch of the engine in Jenbach, GE Power & Water CEO Steve Bolze said GE invested $100m on developing the J920. He said: “In 2006 we decided to invest more than $100m on a new, large gas engine with no return on investment for at least five years in testing market conditions and four years later here it is. We see great potential for the engine in emerging economies like Brazil and Indonesia.”
A prototype of the engine has been undergoing successful testing on a purpose-built test bench at GE’s Jenbacher manufacturing facilities in Austria since late summer.
A large-scale pilot programme will be put the new engine into operation for the first time at the “Stadtwerke” (the municipal utility company) of the town of Rosenheim, Germany during the first quarter of 2011. Following this test phase, serial production is scheduled to begin, and the new engine should be available for use in applications in 50 and 60 Hz countries in 2012.
The J920 is based on proven core elements from the combustion systems used in Jenbacher 6 series. The new engine also employs an innovative three-module concept, which results in a standardized generator-set comprised of the engine itself, a generator and an auxiliary module produced at GE’s Jenbacher plant. In addition, like the recently presented J624 engine, the new J920 is equipped with the innovative two-stage turbocharging system.
The engine reaches full output in only five minutes, which GE Jenbacher says increases its attractiveness for use as cover for demand peaks.