Transmission owners should consider locating staff in 500 kV substations in advance of future hurricanes, and PJM should be quicker to take generation off-line as load is lost, the Operations Committee was told Tuesday.

PJM’s Mike Bryson briefed the committee on lessons learned from Hurricane Sandy, the results of a detailed review by the System Operations Subcommittee Transmission group (SOS-T).

Among the key lessons:

Staffing:

• TOs that manned their 500 kV substations were able to respond to Remote Terminal Unit (RTU) failures quickly and had response crews geographically dispersed, allowing them to get to other substations more rapidly. RTUs collect data from transducers at remote locations and convert it for transmission to the Supervisory Control and Data Acquisition (SCADA) system used to monitor and control the grid.
• Emergency staffing plans should be amended to include provisions for conditions in which control room staff cannot leave due to weather or road conditions. PJM discovered this vulnerability when fallen trees blocked the road in both directions outside its Advanced Second Control Center (AC²) in Milford, PA.

Generation planning:

• Fearing the loss of load and large generators during the storm, PJM ran additional local generation. But while load was lost, generation remained on-line, resulting in high voltage conditions. PJM said it should have taken generation off-line more quickly. Inspections found that none of the equipment that experienced high voltage during the October storm was damaged.

500kV line switching:

• The storm required PJM to perform 500 kV line switching for voltage control for the first time. Before implementing the switching, PJM reviewed generation on-line, potential interactions with Special Protection Schemes, transient stability and Nuclear Plant Interface Requirements. The SOS-T recommended developing a checklist for future use to ensure these studies are consistent and that switching doesn’t create unanticipated problems.

Phones:

• Service on cell phones and landlines was unavailable or spotty but text messages were successfully transmitted. The committee recommended having text-capable phones for operators and crews.

Customer Outage Reporting:

• PJM’s calls to TOs for verbal updates on customer outages distracted the TOs from operations and restoration. PJM plans to develop a tool to scrape the TO websites for these updates.

(See “PJM Year in Review: Storm Recovery, Lower Prices, Continued Growth.”)