This document discusses dry flue gas losses in boilers and methods to reduce them. It notes that rising fuel costs have increased focus on power plant efficiency. Dry flue gas losses occur when excess air leads to higher exit gas temperatures, wasting heat. Causes include air leaks, fouling of heat exchangers, and excess airflow. Reducing dry gas losses provides the greatest potential for efficiency gains. The document recommends optimizing excess air, repairing leaks, cleaning heat exchangers through soot blowing, and using high-alloy materials resistant to corrosion. Proper maintenance and airflow control can decrease losses and lower costs.