August 15, 2006

Currant Creek Power Plant, Mona, Utah

Odis F. Hill, Jr., PE, The Shaw Group, and Robert Van Engelenhoven, PacifiCorp

One-two punch

The Currant Creek Plant was built in two phases, beginning in January 2004. The first phase focused on installing and placing into service the two simple-cycle gas turbines (totaling 280 MW) by the summer of 2005. Both were completed on June 10, 2005, and declared commercial on June 20, 2005—when they were turned over to PacifiCorp operations for dispatching to help meet summer peak demand. The second phase—completing the steam plant—took a back seat to serving prime-time load.

The safe operation of the two simple-cycle GTs last summer, while almost 500 tradesmen were on-site installing the steam turbine and HRSGs, was a testament to the skill and dedication of The Shaw Group and PacifiCorp. Personnel from the two companies had to work closely, on a daily basis, to identify and solve problems quickly—or court disaster.

One example of their ingenuity was installing a large hydraulic damper and a second steel safety plate (with an air gap between the damper and the HRSG) as the solution to the problem of keeping operators and craftsmen safely apart. Others included setting up a lock out/tag out procedure that worked for both teams and commissioning of the final plant's distributed control system during the first phase.

The simple-cycle turbines ran without any forced outages throughout the 2005 summer peak season. On September 23, 2005, Currant Creek was removed from commercial service and put back under control of The Shaw Group for completion of construction of the steam plant. During the second phase, the two HRSGs and the steam turbine were installed, increasing the plant's generating capacity by 245 MW to 525 MW. The entire combined-cycle plant was declared commercial on March 22, 2006, months before this summer's peak-demand season.