Heat recovery

GE Energy and ECOS plan to demonstrate an industrial waste-heat recovery system that will increase the efficiency and output of a 7.2MW biogas power plant.

GE Energy and energy developer ECOS plan to demonstrate an industrial waste-heat recovery system that will increase the efficiency and output of a 7.2MW biogas power plant in the eastern Slovenia town of Lendava, near the border with Hungary.

GE’s new pilot Organic Rankine Cycle (ORC) waste-heat recovery system for gas engines is designed to make onsite power plants that use natural gas, landfill gas and other waste gases more cost effective to build.

The ORC system will allow ECOS to capture more waste heat created by its 7.2MW Bioplinarna Lendava biogas plant. The extra thermal power will be used to produce steam, which in turn will help generate enough electricity to support 300 European homes without using additional fuel.

The pilot ORC system will be installed on one of the three GE ecomagination-certified Jenbacher J420 biogas engines that have powered ECOS’ Bioplinarna Lendava plant since June 2008. The ORC technology will boost the Jenbacher unit’s electrical efficiency by an estimated five per cent.

ORC systems generally offer enhanced energy efficiency by using organic fluids that have lower boiling points than water to create steam for electricity generation. However, due to technical waste-heat recovery constraints, there had been few gas engine-based ORC applications.

Using GE’s gas engine-ORC technology means that all of the waste heat from an engine’s exhaust gas and cooling cycle can be fully captured and used to drive the power plant’s enhanced steam-creation process.

The ORC technology was developed by GE’s Munich corporate research centre and GE Energy’s Jenbacher gas engine business in Austria.