GE has achieved a one percentage point improvement to the efficiency of its flagship, 24-cylinder Jenbacher J624 gas engine by the development and application of two-stage turbocharged gas engine technology.

The new engine also provides a 10% output increase, compared to the single turbocharged version, and is particularly well-suited for operation in hot environments and CHP applications.

The new engine was introduced at a launch event held at GE’s Jenbacher headquarters in Jenbach, Austria, at which representatives from the pilot customer for the first new engine, Red Harvest, a large Dutch greenhouse plant operator, were also present.

Introduced in 2007, the J624 is the world’s first 24-cylinder gas engine for commercial power generation.

With the new system, which GE developed with specialists from ABB Turbo Systems, the J624 achieves an increase from 4 MW to 4.4 MW and offers an electrical efficiency of 46.5%, an increase of about 1%, although this increases towards a 2.5% increment where engines operate in hot and humid environments.

Improved efficiency is, of course, critical for the competitive cost of electricity and for the reduction of carbon dioxide emissions.

‘With this technology breakthrough, GE continues to lead innovation in gas engines and has become the first gas engine manufacturer using two-stage turbocharging technology. While this technology initially is being applied to our largest gas engine, the J624, eventually it will be offered with other engines in our portfolio,’ said Prady Iyyanki, CEO, gas engines for GE Power & Water.

‘The advanced boost pressure allows us to significantly push the gas engine operating range and maintain full output and efficiency at high ambient temperatures and high elevations,’ he added.

The two-stage turbocharging offers a much higher charging efficiency, which significantly contributes to the engine’s overall increased efficiency.

In addition to the higher charging pressure, the technology also improves the power density of the engine, says the company. The new engine will be available to customers worldwide by the summer of 2011.

Prady Iyyanki talked to COSPP after the launch about the very important part of Jenbacher’s business made up of CHP installations.

In the developed countries of the EU, currently around 11% of the total power used is generated from CHP, yet in one country: Denmark, that figure is around 60%. The difference defines Jenbacher’s potential market for the continent, he said.

Highlighting some existing areas where Jenbacher engines are installed in numbers, Iyyanki pointed to the vast glasshouses of The Netherlands, where CHP supplies power for lighting, with excess power exported to the grid; thermal energy for space heating around the clock; and carbon dioxide to stimulate plant growth.

In Asia, several textile factories in Pakistan use Jenbacher engines in CHP mode to supply the energy-hungry processes in a country where the local electricity grid cannot always be relied upon and heat requirements are typically very high.

Third, steel plants in Spain, South Africa and France burn locally available coke oven gas and blast furnace gas in engines from Jenbacher to make power for use on-site.