This research object to determine the effect on the parameters of the gross plant heat rate, specific fuel consumption, fuel efficiency, SO2, NOx, and particulate using coal fuel and palm shells in the operation of 135 MW circulating fluidized bed boiler steam powerplant based on problem that coal power plant produce emissions as one air pollution contributors and have impact on the environment need to reduce emission by convert coal combined with palm shells partially. The research result that the use of combination coal combined with palm shells on 0%, 5%, 8%, dan 10% monitored by using performance monitoring analysis modules including operation on boiler steam powerplant obtained the percentage of 92% coal fuel and 8% palm shells are better than the other percentages. The smallest average value of GPHR 2458.083 kcal/kWh, SFC 0.590 tons/MWh, SO2 202.870 mg/Nm3, NOx 183.543 mg/Nm3, particulate 18.761 mg/Nm3, and the largest average value of fuel efficiency is 85.886%. This result can be used for coal-fired power plants in the development of environmentally friendly fuel alternatives.