Gas turbine (GT) upgrades can lead to excessive steam generation and operating pressure in unfired HRSGs, resulting in the pressure safety valves (PSVs) lifting. Plants are oftentimes forced to throttle the GT to prevent this occurrence, causing decreased power generation, lower efficiencies, and limiting full utilization of the GT upgrade. HRST’s patented FlexTune™ technology can help alleviate this issue while restoring potentially lost MWs from GT throttling.

The HRST FlexTune™ system controls HRSG pressure and helps realize lost megawatts from GT throttling.

  • FlexTune™ controls steam production and pressures in the HRSG

    • Pressure is limited to prevent lifting of PSVs

    • Prevents excessive steam generation above rated capacity

  • Allows GT to operate at 100% load across varied operating conditions

    • Helps GT operate in optimal efficiency range

  • Creates a net postive power output compared to GT throttling scenarios

    • Limits lost megawatt power productions

    • Helps restore CCGT plant heat rate

  • Ideal for CCGT plants in both capacity and energy markets

    • Helps maximize your megawatt power output and capture peak demand payments

FlexTune™ System Features:

  • Flexible Operation

    • System is controllable and operates only when needed (e.g., turned off during low GT load operation)

  • Tunable Setpoints

    • Pressure or steam production setpoints can be created to throttle the HRSG more or less depending on plant requirements

Use the following to request a brochure: HRST FlexTune™

This is an example of the FlexTune™ system for return bend style economizer applications (3 different views)