This model is a development of the 50 Hz J420 introduced in 2002 to fit into the output gap between the 1MW J320 GS and the 1.8 MW J612 GS engines, a family of drivers launched as a new generation of high efficiency units under the Jenbacher ‘high-efficiency concept.’ More than 300 of the 50Hz J420 GS units have been installed around the world, operating on a variety of fuels.

The new 60 Hz model, which is being sold on the same high-flexibility ticket, offers good thermal efficiency at high specific outputs at 1800 rpm, suitable for natural gas or a variety of other fuels such as landfill gas, biogas, sewage gas and coal mine gas. GE says that the J420 has completed rigorous endurance and performance testing at its manufacturing facilities in Austria, inherited at the time of its purchse of Jenbacher.

GE says that the J420 GS is characterised by a very high power density owing to its highly compact, robust design and small footprint, resulting in low investment in foundations and buildings. Key advanced efficiency features include swirl-optimised four-valve cylinder heads, a Miller timing combustion system and high-performance spark plugs developed in-house by GE. The new components can operate for longer between overhauls, typically 30 000 hours for cylinder heads and 15 000 hours for spark plugs.

Thermal output of the new model will be about 5700 MBTU/h when fuelled by natural gas and 5400 MBTU/h for biogas. Electrical efficiency is 40.8%, with a total engine efficiency of up to 86.6%.

First orders in North America for the new model include units destined for natural gas cogeneration projects and others that are being installed for landfill and sewage gas-to-energy applications. The first J420 for 60Hz applications will be commissioned in early 2007, with the first field installation entering service during the first quarter of 2007.

…while big brother goes underground down under

A new energy plant in south-eastern Queensland, Australia, consisting of 11 of GE Energy’s largest Jenbacher gas engines, is being built to use coal seam gas from unmined coal beds. The gas in question is more than 90% methane and is of stable enough composition to be fed directly into gas engines. The 30 MW Daandine power generation project, which has a total installed base of 33.5 MW, is being developed by Arrow Energy NL in the Surat Basin, approximately 250km west of Brisbane immediately to the south of Arrow’s Kogan North project. Arrow Energy is a specialist in the exploration and development of such coal seam gas resources in south and central Queensland and northern New South Wales.

GE supplied 11 of its Jenbacher JGS 620 GS-S.L gas engine generating sets including generators and standard engine accessories that include gas trains and DIA.NE control panels. The company also provided the engine management system while overall site SCADA control and turnkey design was provided by Clarke Energy, a GE distributor that also carried out the installation on behalf of Arrow. Delivery to the site was completed in November 2006.

The units are rated at 3.04MWe with an electrical efficiency of 43.3%. First sales of electricity from the Daandine station were expected before the end of 2006. All output will be sold to New South Wales energy retailer Country Energy under a long-term power purchase agreement.

GE Energy’s new 60 Hz version of its Jenbacher 1.46 MW gas engine generating set