Development of gas mixture system of biogas and natural gas for gas engine cogeneration

Tokyo Gas has developed a compact and high-efficiency cogeneration system which can run with the mixture of biogas and natural gas, based on a new concept. To utilize the biogas whose amount of production varies from time to time, we have developed a gas mixture system that utilizes as much biogas as possible under simple and reliable control. Also, we have developed an air dilution system of natural gas to maintain stable combustion at the engine. Due to this system, the mixture ratio of biogas and natural gas can be anything from 0% to 100%. Further more, since this system is equipped with multiple safety measures, cogeneration system can continue its operation even after any thinkable malfunctions of the system. This gas mixture system and cogeneration plant has been installed at a beer brewery near Tokyo, and operating without any major troubles.