Exelon Generation is planning to build two combined-cycle gas turbine (CCGT) units in Texas using a new General Electric technology that it says will make them among the cleanest, most efficient CCGTs in the state and the nation.
The new units are being built on existing Exelon sites: one at Colorado Bend Generating Station, currently a 498 MW natural gas plant in Wharton County, Texas; and the other at the 704 MW Wolf Hollow natural gas plant (pictured) in Granbury, Texas. Each new unit will add approximately 1,000 MW of capacity to their respective sites.
Alstom Power will provide the heat recovery steam generators to produce the steam necessary to maximize generating capacity and efficiency at each unit.
Additionally, the new units will be cooled with air instead of water — a move to increase water efficiency in drought-prone Texas.
The HA turbines apply advanced materials from GE aircraft engines, incorporating single-crystal alloys and thermal barrier coatings to deliver longer parts life for lower lifecycle costs. This enables the turbines to operate at higher temperatures (over 2600 degrees F), increasing efficiency and further reducing ongoing maintenance costs, GE says.
Exelon expects construction of the units to begin in 2015 with commercial operation targeted for 2017.
According to its most recent sustainability report, Exelon says it reduced or avoided more than 18 million metric tons of greenhouse gas emissions in 2013, surpassing its goal of eliminating 17.5 million metric tons of GHG emissions per year by 2020.