Techno-economic assessment for optimal electricity and diesel fuel production using corncob gasification-Fischer Tropsch process

Biomass gasification technology has been developed in Indonesia in the last 30 years. However, the use of synthetic gas directly on diesel engine and steam turbine for electricity generation has a relatively low efficiency. New technology has been emerged to integrate thermal gasification with Fischer-Tropsch (FT) synthesis which then can be combined with heat and electricity production. This paper consists of techno-economic study for optimal electricity and diesel fuel production using corncob gasification integrated with FT process. Optimal production (409 GWh electricity, 58,900 kL fuel) can be achieved when using air and operating pressure 25 bar. Calculated production cost is 6,569 IDR/kL FT fuel and 245 IDR/kWh electricity. With average Indonesian electricity tariff 1,123 IDR/kWh, BGFT electricity production cost is much lower, about 22% of Indonesian electricity tariff. Corncob price change has higher effect on electricity production cost than water price change. So, if the electricity cost wants to be hold in economic level, then the corncob price should be held constant. The price will stay constant if there are no competitor that would use corncob as raw material. As of now, corncob still considered as waste that are not used for economic activities.