After final evaluation of various systems at J.K. Spruce Unit 2, CPS Energy has postponed re-starting the newly constructed coal plant.

The delay centers on the power plant’s generator step-up (GSU) transformer, the main transformer that provides the power to nearby substations through high-voltage power lines. Testing in late summer indicated a potential problem with the transformer, and CPS Energy proactively took the plant off line for more detailed inspections of that and other systems.

The Hyundai-manufactured transformer is under warranty. In recent weeks, Hyundai technicians have been on site to inspect the equipment while the manufacturer works with the utility to repair or replace the component. 

“We feel that the manufacturer and Calaveras Power Partners are being responsive in dealing with this issue,” said Mike Kotara, senior vice president of fossil generation. “We were pleased with the operation of the plant through the summer. The plant operated well through Sept. 3 when it was brought offline, and it helped keep our customers’ bills lower during the high-demand summer months.”

Kotara added that CPS Energy is generating plenty of electricity from its other power plants to meet customers’ electricity needs now, during the low-demand fall months.

CPS Energy took over operations of the $1 billion dollar coal plant in May 2010, when the utility assumed operational control of the plant from its construction contractor. Following a dedication ceremony held in September, Spruce Unit 2 was expected to be online again this month.

“Our process for checking the plant’s systems is similar to what you do when you move into a new home,” said Plant Manager Jeff Kruse. “We’re working a punch list of items
that need some follow-up. Overall, we’re pleased with the plant’s performance. While it’s been offline, we’ve had a chance to inspect the boiler and check the emissions control systems, and all of those systems are operating very well.”

Spruce Unit 2 is expected to meet about 25 percent of CPS Energy’s electricity demand.