Closed Circuit

​By Lisa Meiman 

​On March 26, 2016, a cascading failure of a power distribution system caused a critical power outage at the Sierra Nevada office in Folsom, California, interrupting dispatch monitoring and control of the Sierra Nevada electrical grid. 

Power Operations employees initiated continuity of operations procedures and relocated to the backup dispatch center to continue critical grid operations. After power was restored, the team evaluated the overall power distribution system. 

“The analysis identified the need to improve reliability, modernize obsolete equipment and expand monitoring and control capabilities for the Folsom station service system,” said Program Manager Wayne Icenhower, who works under the Wyandotte Services contract. “Safety objectives consistent with industry standards were also identified, including the reduction of arc flash hazards for maintenance personnel.” 

On Sept. 24, employees at the Folsom office welcomed a new state-of-the-art switchgear, the key component to improving electric service at the site. 

“The switchgear includes a secure communication path to SN’s Supervisory Control and Data Acquisition and energy management systems with the ability to monitor over 150 data points,” said Icenhower. “Its design replaces the function of several pieces of legacy equipment and increases reliability, redundancy and maintainability of critical power system infrastructure.” 

The switchgear is also capable of isolating a main bus fault while keeping generator backup available on the alternate source. 

The switchgear is only one of the upgrades occurring at SN’s Folsom office. Other upgrades include two new and larger station service transformers, two new uninterruptible power supply systems and a high-speed static transfer switch. 

The new equipment will undergo commissioning activities in December with cutovers to the permanent switchgear expected early next year. 

“The Folsom office station service system plays a crucial role in providing reliable and continuous operation of SN’s electrical grid,” said Icenhower. “Its modernization will provide reliable power for decades to come.” 

Note: Meiman is a public affairs specialist.

New switchgear

The Sierra Nevada Regional Office in Folsom, California, installed a
new switchgear to improve electric service to the facility. (Photo by
Wayne Icenhower)

Last modified on March 8th, 2024