Decision making on most economical coal for coal-fired power plants under fluctuating coal prices

A long-term (8 years) experimental investigation has been carried out to analyze the effect of coal quality on the economy of power plants and to develop a predictive method for the determination of the most economical coal in a fluctuating coal market. The research results show that the facility maintenance costs, the combustion-supporting oil consumption, and the frequency of tube explosion increase exponentially with the ash content increasing, and the total maintenance costs increase sharply when the quality of the coal declining significantly from the designed coal. Taken into considerations the coal-purchasing costs, facility maintenance costs, emission costs, etc., a comprehensive mathematical model has been developed to predict the most economical coal, which is the coal with an ash content of 28.9% for the power plant investigated. Finally, a rapid calculation method has been proposed to determine the most economical coal in a fluctuating coal price market.