The KEY component in recovering thermal energy is the heat exchanger, which transfers the majority of the thermal energy from the hot exhaust gas to the circulating water powering the ORC Powerbox unit. Airec products can be used for applications with larger volume flows, lower pressure drops or completely asymmetrical flows. Airec heat exchangers are more compact and efficient with > 95% of kW of recovered energy over traditional heat exchangers that extract only up to 80% of thermal energy. Not only are Airec's heat exchangers more efficient than their closest known competitors but they are almost of the weight and significantly smaller.

CoGen has an exclusive agreement for the use of Airec heat exchangers in Australia.

Having recovered the wasted heat with the world's most efficient heat exchanger, CoGen wanted to ensure it would extract the most power from the recovered heat. It's search for the most efficient heat engine lead CoGen to Opcon's Powerbox. The best technology for converting recovered heat into power is the Organic Rankine Cycle (ORC). There are several manufacturers of ORC generators but none as good as the Opcon Powerbox. All other units use a common turbine to derive work from the superheated working fluid. The Opcon Powerbox uses Opcon's patented twin screw expander technology. This twin screw technology doesn't require superheating of the working fluid to a dry vapour. In fact it operates identical or improved efficiencies even if the working fluid is wet, thus allowing the system to continue operation at reduced temperatures.

CoGen has an exclusive agreement for the use of the Opcon Powerbox in Australia, Thailand, Singapore, Malaysia and Sub-Saharan Africa.

CoGen's is currently at the stage of development where

• Engineering designs are well advanced
• The first Opcon Powerbox arrived and cleared customs in October 2009
• The first Airec heat exchangers have been ordered and are being manufactured
• Henderson landfill gas site (Waste Gas Resources) has been selected for the first installation
• The required legal agreements are being developed with some of Australia's best energy lawyers

A heat exchanger increases the temperature to vaporising temperature. The media becomes a gas.

The gas expands over the expander and the expander drives a generator that delivers electricity to the grid.

A heat exchanger with cooling water reduces the temperature and pressure to give highest possible pressure difference over the expander.

A pump increases the pressure of the fluid to 30 bar and circulates the media.