14 December 2004 – Japanese companies Tokyo Gas Co. and Hitachi Air Conditioning Systems Co. are reported to have developed a cogeneration system that boasts a world-leading 90 per cent energy efficiency.
The system generates electricity with a gas engine that is 40 per cent energy efficient, and combines this with an improved version of a gas-absorption type of water-cooling system that uses waste gas from the engine to operate.
Building more heat exchangers into the water-cooling system boosted thermal transfer and increased its co efficiency of performance (COP) to 1.35.
The companies plan to market the new cogeneration system in March 2005, targeting sales at supermarkets and other commercial users that need to operate machines continuously to keep items cold. Six models have been prepared, with power
outputs ranging from 550 to 920 kW, and cooling capacities ranging from 400 to 700 refrigeration tons.