A Methodology for Computation of Experimental Annual Station Heat Rate Benchmark

This paper presents a methodology for assessment of annual heat rate of a coal fired thermal power unit based on a snap shot test to which various factors contributing to annual effects are added. This method is successfully used in a number of stations and represents the Unit Heat Rate (UHR) and Station Heat Rate (SHR) fairly well. This method is not a substitute for measurement of heat rate by direct measurement of coal flow and energy generated and is applicable only where direct measurement of coal flow into an individual boiler by gravimetric feeders or belt weighers is not available. This method is superior to other methods in view of its total coverage of all effects and no annual factor which affects heat rate is left out. Hence it is popularly accepted by most thermal stations. This method is superior to backward computation of UHR from SHR by apportioning.