Latest

  • 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 […]

  • Why new U.S. supercritical units should consider T/P92 piping

    T/P92 is being heralded as a superior and lower-cost alternative to T/P91 for new power plants with pressures above 3,600 psi and temperatures above 1,100F—such as the supercritical and ultra-supercritical units proposed to be built in the U.S. over the next few years. The switch from T/P91 to T/P92 would represent the next step in […]

  • Marmy stops dreaming

    Steve Elonka began chronicling the exploits of Marmaduke Surfaceblow—a six-foot-four, steel brush-mustached marine engineer with a foghorn voice—in the pages of POWER in 1948. That was the year that Marmy raised the wooden mast of the SS Asia Sun with the aid of two cobras and a case of Sandpaper Gin. This classic episode, written in the late 1960s, shows that even minor consequences of a steam turbine overhaul can cause problems. And as Marmaduke shows, solving any problem requires equal parts judgment, logic, and experience. Enjoy.

  • Economic dispatch done best when done locally

    Both the states and the federal government are looking at who should decide which power plants are used at any given moment to meet demand. In question is which approach will reliably serve customers with the lowest-cost electricity. The Energy Policy Act of 2005 (EPAct) raised the issue when it directed the Federal Energy Regulatory […]

  • Fluid dynamics of the HRSG gas side

    Designers of heat-recovery steam generators are using computational fluid dynamics software as one tool to reveal the invisible forces affecting the flow over, under, around, and through structures such as inlet ducts, distribution grids, and guide vanes.

  • Designing wet duct/stack systems for coal-fired plants

    A multitude of variables must be accounted for during the design and development of a wet-stack flue gas desulfurization system. The five-phase process detailed below has proven effective on more than 60 wet-stack system design studies. A basic understanding of these concepts will help inform early design decisions and produce a system amenable to wet operation.

  • A breakthrough in hydroturbine design

    Focus on O&M

  • How leaking valves drain profits

    Focus on O&M

  • New day, new DCS

    Focus on O&M

  • Gas turbine "refueling" via IGCC

    The jury is still out on the economic and technical feasibility of burning gasified coal to generate electricity. Gasification technology has yet to be proven on a utility scale, especially with Powder River Basin coal as the feedstock. And on the generation side, there are more questions than answers about the capital cost and availability of integrated gasification combined-cycle (IGCC) plants. But with natural gas prices high and rising, it’s definitely worth examining whether it would be economically and technically feasible to convert the existing U.S. fleet of gas-fired combined-cycle plants to burn gasified coal.