Gas

Increased cycling of combined-cycle plants has made precise control of attemperator spray water within heat-recovery steam generators more important if damage to their hardware and piping is to be avoided. Complicating the issue is the industry’s still-limited experience with cycling and the fact that demands on the attemperator and turbine bypass of cycled plants are more stringent than those on baseloaded units.

Nearly five years ago, a major IPP began standardizing steam cycle chemistry feed, control, and monitoring across its combined-cycle fleet. This article discusses the steps taken, the costs incurred, and the technical and financial benefits achieved. Although the project focused on non-cogeneration plants, the findings detailed below are broadly applicable to other kinds of plants. However, the specific implementations (especially of the chemistry standards) described may have to be modified slightly for application to cogen plants.

  The U.S. needs to add 600 to 800 billion cubic feet (Bcf) of natural gas storage capacity ASAP. Independent storage providers (ISPs) are the entities best equipped to build this needed infrastructure, but they continue to be restrained by anachronistic regulatory policies. The Federal Energy Regulatory Commission’s (FERC’s) December 2005 rule-making to modify its […]

GE Energy’s latest "first" is in Turkey, where the Frame 6C gas turbine-generator—a younger cousin of the popular Frame 6B—has made its commercial debut. The turnkey 130-MW combined-cycle plant, called the GE206C, comprises two 40-MW Frame 6Cs, one GE steam turbine-generator, two heat-recovery steam generators, and a distributed control system. The gas-fired plant (Figure 1), […]

Munich-based Siemens Power Generation (PG) recently finished building the 384-MW combined-cycle Tahaddart Power Plant in the city of the same name in Morocco (Figure 2). The turnkey project, which is about 20 miles south of Tangier, was completed in 25 months. The plant’s natural gas fuel comes through a new, 8-mile-long spur that connects to […]