PWP Successfully Tests New Equipment That Could Eliminate Rotating Power Outages in Pasadena

Pasadena Water and Power has successfully completed testing of new equipment installed at PWP’s Glenarm Receiving Station that may reduce local power disruptions in the future. 

The new equipment enables the utility to quickly transfer part of its customer load to the power lines from the Los Angeles Department of Water and Power (LADWP), in case of power outages.

The successful testing was conducted earlier this month, PWP Interim General Manager Jeffrey Kightlinger said. 

Background

“PWP receives most of its power from power generation plants and renewable power facilities located outside the City. The power is sent to the City through high voltage transmission lines under the direction of the California Independent System Operator (“ISO”),” according to the PWP. 

In August 2020, the ISO ordered their participating utilities, including PWP, to curtail load because they had a shortage of power due to high heat and power system issues. 

In the case of PWP and other similar utilities, load curtailment means turning off a portion of their customers for an hour, and then rotating the outage to another set of customers until the situation is resolved. 

Responding to the load curtailment events by ISO, PWP began exploring options to minimize power disruptions in the city during such events. 

As a solution, PWP looked to the past and took advantage of existing power lines that come to Pasadena from a neighboring utility, the Los Angeles Department of Water & Power (“LADWP”). 

“Originally built to bring power from the Hoover Dam to Pasadena in the 1930s, PWP later switched its incoming power to the ISO in the early 1970’s and those lines were placed on stand-by for emergency use in case there was a total loss of power from the ISO.” 

With the new equipment, PWP will be able to continue supplying electricity to its customers at times when the ISO has insufficient power and orders participating utilities, including PWP, to curtail load. 

PWP said the new Grid Reliability Project will enable it to seamlessly switch back to those LADWP lines at any time that ISO curtails load to Pasadena. 

Kightlinger said for the first time in over 50 years, LADWP’s system served load in Pasadena during the recent successful test.

“In the future, if the ISO needs to have utilities curtail load due to a system emergency, this load transfer to the LADWP lines should satisfy that request without the need for rotating power outages for PWP customers,” he said.