Want to Learn More? 

What can Economizer Outlet Gas Temperature Control do for you?

GE Steam Power offers advanced boiler optimizations and systems to control the gas temperature to the SCR so your plant can operate at low load and still comply with environmental restrictions. These systems are fully integrated with your boiler’s control system (DCS) and are tailored to meet your plant’s needs.

Based on your unit, we can customize the right boiler solution to meet your operating requirements. Two examples for controlling gas temperatures used in power plant boilers are:

  • Subcritical boiler: Our patented Hot Water Recirculation System (HWRS) controls exit gas temperature by extracting a portion of hot water from the boiler downcomers and mixing it with the feedwater upstream of the economizer inlet.
  • Supercritical boiler: Our patented Economizer Recirculation System (ERS) recirculates waterwall outlet fluid. 

These boiler control systems increase the fluid inlet temperature to the economizer, which increases the economizer outlet gas temperature at reduced loads. There are other effective solutions available depending on your unit and your operating requirements.


  • Easy to control gas temperatures to SCR at low loads
  • Operates only during required loads, avoiding parasitic power used at high loads
  • Increases boiler demand flexibility
  • Operating SCR at low loads avoids increased startup/shutdown cycles, reducing wear and tear on your boiler