The document discusses methods for assessing the energy efficiency of boiler performance. It describes standards from British and ASME for testing boilers under steady load conditions. The direct and indirect methods for determining boiler efficiency are outlined. Instruments required are listed, including flue gas analyzers, temperature indicators, and facilities for analyzing fuel and water samples. Key aspects of indirect method heat balance calculations for a coal-fired boiler are mentioned. Best practices are listed for improving boiler selection, operation and maintenance for energy efficiency.