The final text of the integrated gasification combined cycle (IGCC) 20% more efficient than the existing system will start shortly. Located in Fukushima Prefecture, Clean Coal Power Research Institute founded jointly by 10 electric power companies will start the final test of its system coming July. The test to verify the durability and economic potential is scheduled for March 2013. The demonstration system has a capacity of 250,000 kW enough to supply electricity for about 100,000 households. The IGCC drives the gas turbine by burning coal gas, creates steam using the exhaust heat after burning, and runs the steam turbine using the created steam and the steam inside the furnace of coal gasification. The new system has 20% higher generation efficiency with 20% smaller amount of carbon dioxide emissions. In the demonstration test between Sept. 2007 and Mar. 2011, the company successfully achieved the running time of 5,000 hours and the generation efficiency of 42%. In the final test, it aims for the running time between 6,000-7,000 hours that is equivalent to 70-80% of the annual operation rate. Maintenance cost will also be studied. The demonstration system was damaged by the great earthquake, but the maintenance is expected to end mid-July.