Commissioning begins at Dry Fork Station

With operation a little more than a year away, the process of getting plant systems up and running - called commissioning - has begun.

Basin Electric Power Cooperative - March 7, 2010

With operation a little more than a year away, the process of getting plant systems up and running - called commissioning - has begun. The first step was the backfeed of electricity through the switchyard to the high-voltage switchgear within the power plant. This milestone happened on Feb. 25. Up until that point, the temporary power supply for the construction site came from a substation owned by Basin Electric-member Powder River Energy Corporation.

Doug Ramsey, Basin Electric construction manager at the Dry Fork Station, said the backfeed process included 35 of more than 640 steps on the checklist leading to commercial operation.

"Crews from Sargent & Lundy and Basin Electric proceeded with the backfeed process cautiously to make sure all protective relays along the way would trip if problems were encountered," Ramsey said. Detailed lock-out/tag-out procedures were followed to ensure safety for all personnel on site.

Electricity was successfully fed through the reserve auxiliary transformer at 8:33 a.m. on Feb. 25. From there, the main breakers were closed on the 13.8-kilovolt switchgear, feeding electricity into the power plant. About 24 hours later, Ramsey said the reserve auxiliary transformer was de-energized, and samples of its oil were taken for testing before re-energizing it.

The next major step in the commissioning process is the production of demineralized water, which is scheduled for April.