Gas

Just as GE Energy, Siemens, and Mitsubishi Heavy Industries (MHI) in May announced gas combustion technology developments—each seeking to push the 60% barrier with new gas turbine designs—Alstom has quietly been upgrading its KA26 combined cycle power plant. (See the July 2011 “Global Monitor” for more information on the GE, Siemens, and MHI turbines.) The firm says that the next generation of the 500-MW power plant, based on the advanced class GT26 gas turbine, features “achievable” efficiencies of over 61%, increased flexibility, and more than 350 MW, which can be delivered in less than 15 minutes to help integrate renewable energy sources (Figure 3).

Two years after it laid the foundation stone, Germany’s E.ON on June 27 opened Hungary’s most efficient combined cycle gas turbine (CCGT) power plant (Figure 7). The €400 million ($573 million) plant in Gönyü has a capacity of 433 MW and an efficiency of over 59%, E.ON claims. Siemens supplied the main components: an SGT5-4000F gas turbine, an SST5-5000 steam turbine, an SGEN 5-3000W generator, and the entire electrical and instrument and control equipment. The natural gas–fired power plant is of single-shaft design with the main components arranged in a single driveline.

CTG Universidad is a two-unit combustion turbine plant commissioned in late 1970 by the Comisión Federal de Electricidad (CFE) on the north side of Monterrey, Mexico’s third-largest city and an important industrial center. By the 1990s, the two 14-MW turbines were obsolete, used sparingly, and slated for demolition in 2010. However, by 2002, portions of Monterrey began experiencing power restrictions caused by a lack of sufficient reactive power production, and that situation presented an opportunity for the plant. By repurposing an old combustion turbine for use as a synchronous condenser to provide local reactive power, CFE significantly reduced local power supply limitations. For that savvy plant repurposing, CFE’s CTG Universidad Unit 2 is the winner of POWER’s 2011 Marmaduke Award for excellence in power plant problem-solving. The award is named for Marmaduke Surfaceblow, the fictional marine engineer and plant troubleshooter par excellence.

Cycling your steam power plant is inevitable, so now is the time to learn how to minimize equipment damage and assess the true costs of cycling. Whether cycling is required by the grid operator because of renewable integration or other factors, you must be proactive about updating operating processes and upgrade equipment so the transition to cycling operation goes smoothly.

As coal-fired power plants increasingly operate in cycling modes, many plants are confronting the potential for higher levels of component damage and degraded performance of environmental control equipment. Generators and EPRI are working together to find ways to mitigate the effects of cycling operation and to manage the transition of formerly baseload plants to flexible operation.

Gas turbine makers GE, Siemens, and Mitsubishi Heavy Industries (MHI) in the last week of May separately profiled unprecedented results from development or testing of three innovative combined-cycle gas turbine (CCGT) technologies.

It may seem counterintuitive, but the strategic coupling of simple- and combined- cycle technologies with renewable generation could establish the conditions necessary for adding more renewable megawatts to transmission grids around the world.

If you needed additional proof that the power industry is changing, the ELECTRIC POWER keynote and panel discussions over the past few years have provided it—top-of-mind issues have been significantly different each year. For the 2011 keynote speaker and panelists, the challenges of reliability, regulatory compliance, financing, and getting the fuel mix right took center stage. In the wake of Japan’s nuclear crisis, safety also featured prominently.

Spain has served as both exemplar and scapegoat when it comes to renewable energy policy. Though power policy must necessarily accommodate specific national resources and goals, Spain’s experience as an early and eager adopter of renewable energy technologies and subsidies is a cautionary tale of how the best intentions can have unintended consequences.

Fourteen years ago, the MHI T-Point demonstration combined-cycle plant in Takasago, Japan, changed the way modern gas turbines are validated under real operating conditions. In February, T-Point marked yet another milestone by starting to validate the world’s largest and highest efficiency gas turbine, which operates at the unprecedented turbine inlet temperature of 1,600C.