Thermodynamic and economic assessment of power plant expansion from 140 to 200 MWe in Kamojang - Indonesia

Abstract

Kamojang power plant is the first geothermal plant in Indonesia. The two-phase steam-dominated reservoirs produce steam to service three turbo-generator units with a total capacity of 140 MWe. Unit one, 30 MWe, began commercial operation in 1982, followed by two units in 1987, 2H55 MWe. Further evaluation of the resources indicates that it is possible to add a 60 MW turbo-generator for 25 years to fill the high electricity demand in the Java-Bali interconnection grid system. The proposed 60 MW turbo-generator plant is a condensing turbine with turbine inlet pressure in the range of 6-8 bar, and mass flow rate in the range of 500-540 tons/h. Increasing the well head pressure will increase utilization efficiency to a range of 58-62%. Steam is supplied mainly from the southeast part of the 14 km2 proven reservoir. A new power house should be located in the same area as the existing one to minimize environmental impact and reduce landscape costs, while giving an increase in length of the steam transportation piping system. The total transportation pipe length is about 2.5 km, and it has a pressure drop in the range of 1.5-2.0 bar...