GE has unveiled its latest simple cycle gas turbine, the LMS100, flagged as the world’s most energy efficient turbine of its kind and produced as a result of what the company is calling its ‘most extensive business synergy to date’. Certainly the given thermal efficiency figure of 46% for the 100 MW machine is significantly higher than the industry norm of around 37%.

It is also the most extensive collaboration of design and manufacturing in GE’s history, with four GE business units and three other companies (Volvo, Sumitomo and Avio) participating in the development programme. GE has combined components from GE Power Systems (heavy-duty frame gas turbines), and GE Aircraft Engines (aeroderivative gas turbines), to produce significant efficiency improvements, up by 10% on GE’s highest efficiency gas turbine on the market today, the LM6000.

A key reason for the high figure is the incorporation of off-engine intercooling technology within the compression section of the gas turbine, the first time it has been employed in a modern production gas turbine in the power generation industry.

The LMS100 has been developed primarily for simple-cycle applications in power generation, although it is said to be suitable also for CHP and combined-cycle applications, and should be available for mechanical drive applications in the future. In combined cycle, the efficiency would be 54 %, lower than the industry maximum. GE say that the LMS100 offers characteristics not available in other 80 to 160 MW class gas turbines today, including high part-power efficiency, cycling capability without increased maintenance cost, low lapse rate for hot day power, and a modular design for ease of maintenance and high availability. It can start and achieve full power in 10 minutes and has load following capability. At 50% turndown, the part-power efficiency is 40%, greater than most gas turbines at full power. With a low hot day lapse rate, no inlet conditioning is required, reducing installed cost.

The LMS100 can operate in both 50 and 60 Hertz applications without the need for a speed-reducing gearbox. The aerodynamically coupled or free power turbine is designed to operate efficiently in either frequency by changing the first stage power turbine nozzle. All other turbine components are identical, providing cost savings and increased reliability. Reliability was a major design requirement and focus for the LMS100, according to GE, who are describing it as having “designed-in reliability”.

The key areas for the LMS100 are in the peak and mid-range dispatch power generation markets, according to John Rice, CEO of GE Power Systems. “The fast start, cyclic capability and flexibility are significant benefits in these markets”. The LMS100 will undergo development testing beginning in May 2004. The first production units will be in the standard annular combustor (SAC) configuration and are expected to be available in the second half of 2005. The steam injection for power augmentation (STIG) configuration will be available in early 2006, followed by the dry low emissions (DLE) version later in 2006. See also pp 30-31.