Incremental Heat Rate and Optimization: New Applications for ASME PTC-PM Performance Monitoring Guideline

The ASME Performance Test Code on Performance Monitoring (PTC-PM) provides non-mandatory guidelines for monitoring and optimizing the performance of power generation plants. Plant types covered in the guideline include traditional fossil fired steam cycle plants, simple gas turbines, combined cycle gas turbine based plants, and the steam cycle and balance of plant equipment of nuclear fueled plants. PTC-PM is a comprehensive document, covering such topics as instrumentation selection, monitoring software implementation and containing case studies to explicitly show how performance monitoring can be used to identify and resolve the sources of lost performance. This paper will deal with the new information in one of the updated sections included in the latest version of PTC-PM: Incremental Heat Rate. Incremental heat rate is the ratio of the heat input required for a step change in net power output for a power plant. Incremental heat rates are normally given in units of Btu/kWh or kJ/kWh. Knowing how the incremental heat rate changes from one operating point to another is essential planning the most economical dispatch schedule for a plant. This paper will cover the various aspects of incremental heat rate and its applications, as well as methods for determining incremental heat rate at different facilities in accordance with PTC-PM. Examples of estimated incremental heat rates for a variety of power generation facilities are also provided.