Instrumentation & Controls

  • Air heater leakage: Worse than you think

    Rotary regenerative air heaters capture and recycle about 60% of the heat energy exiting the boiler—energy that would otherwise go up the stack. For a 500-MW coal-fired plant, the recycled energy amounts to about 1.5 billion Btu per hour, and reusing it reduces fuel consumption by about 1,500 tons per day. Although most performance engineers […]

  • Siemens units keep pace

    Earlier this February, Siemens Power Generation’s (SPG’s) factory in Berlin delivered its 500th gas turbine. The SGT5-4000F (Figure 2), formerly called the V94.3A, is nominally rated at 270 MW and weighs in at about 300 metric tons. With this shipment, the Berlin facility can boast of having built gas turbines with a cumulative capacity of […]

  • New day, new DCS

    Focus on O&M

  • Constant and sliding-pressure options for new supercritical plants

    Sliding-pressure, supercritical plants are all the rage. They generally include certain design features developed for markets and operating environments outside the U.S., where new coal-fired plants have been built in recent decades. U.S. market conditions are different, and considerable capital cost savings—with negligible operating cost differences—are possible if technology options are considered for the next wave of supercritical and ultra-supercritical steam plants.

  • Understanding refractory failures

    Compared to most pieces of a power plant, refractory costs very little to install. Yet, if improperly manufactured, specified, stored, mixed, installed, cured, or dried, refractory may cause problems that can significantly decrease a plant’s operating efficiency and flexibility. Like Rodney Dangerfield, refractory design and installation deserve more respect.

  • Long-term catalyst health care

    Now that many U.S. selective catalytic reduction (SCR) systems are in their fifth or sixth year of operation, a number of utilities are shifting their attention from implementing the technology to operating and maintaining it. Catalyst management and performance are key to the successful operation of any SCR system.

  • Estimating SCR installation costs

    The EUCG surveyed 72 separate installations of selective catalytic reduction (SCR) systems at coal-fired units totaling 41 GW of capacity to identify the systems’ major cost drivers. The results, summarized in this article, provide excellent first-order estimates and guidance for utilities considering installing the downstream emissions-control technology.