Oakland, CA… With high temperatures continuing across California and the West, the state’s grid operator has again directed utilities including Pacific Gas and Electric Company (PG&E) to prepare for possible rotating power outages due to the potential for electricity supply on the larger Western region grid to fall short of the increased demand.

Rotating outages are a series of controlled outages that would affect customers for 1-2 hours. Rotating outages would relieve stress on the grid to help prevent more widespread power outages.

To help avert rotating outages, the California Independent System Operator (CAISO) and California utilities are strongly urging customers to continue conserving power during today’s Flex Alert until 9 p.m. tonight.

For the past week, Californians and PG&E customers have heeded the call for conservation and averted the need for rotating outages. But extremely high temperatures are being recorded around the state today so the need for afternoon and evening conservation continues.

Customer Notifications

As of 2:30 p.m., the CAISO has not asked utilities, including PG&E, to implement rotating outages. However, out of an abundance of caution, PG&E has given advanced notification to approximately 525,277 customers to prepare for potential rotating outages this evening in case they need to take place. The CAISO supports utilities notifying their customers of potential power outages so that customers can be ready.

If electricity demand conditions do not improve, CAISO could direct PG&E and other utilities to begin rotating outages. CAISO oversees the larger power grid and balances energy demand with supply.

For purposes of rotating outages, PG&E’s service area is divided into areas called blocks. Each block is made up of several neighborhoods. Customers can visit www.pge.com/rotatingoutages or check their printed bill for details and to check if their outage block may be affected.

PG&E is Preparing for Heat Related Outages

Widespread heat events pose unique challenges to the state’s energy grid. In addition to the energy supply concerns driving Flex Alerts, sustained high temperatures have the potential to damage electrical equipment, leading to local outages. PG&E has activated its Emergency Operations Center and is mobilizing the necessary personnel and materials to be able to restore power safely and efficiently.

Heat-related equipment outages can occur during periods of sustained high temperatures. Transformers, which distribute power to homes and businesses, need a period of time when they can cool down, which usually happens overnight when energy usage and temperatures drop. Heat events with sustained high overnight temperatures can put stress on transformers, causing them to fail. This is more likely to occur in area where coastal influence normally results in lower evening temperatures, rather than in interior valleys that routine experience extremely hot weather.

PG&E uses outage prediction models to help determine when and where potential power outage risk could be elevated and uses the latest technology to help restore power more quickly and efficiently during a heat wave. This includes automated equipment that “self-heals” the grid, as well as timely and accurate outage data from its SmartMeter network.

PG&E is positioning crews in areas with higher potential for heat-related outages, including coastal areas that don’t normally experience sustained hot weather. PG&E has troublemen, who are the company’s first responders to an outage, and electric restoration crews working across the service area ready to respond and restore power safely and as quickly as possible in an outage. Additional troublemen and crews are on standby, and PG&E will increase staffing in response to the ongoing heat wave as needed. PG&E is mobilizing necessary materials to be able to restore power safely and efficiently.

How Customers Can Reduce Energy Right Now

Here are ways for PG&E customers to reduce stress on statewide power supply:

Today, during the Flex Alert from 4 p.m. to 9 p.m.:

Set thermostat at 78 degrees or higher, health permitting: Every degree above 78 represents an appropriately 2% savings on cooling costs.

When it’s cooler outside, bring the cool air in: If the outside air is cool during the night or early morning, open windows and doors and use fans to cool your home.
Avoid using major appliances.
Turn off all unnecessary lights.
Avoid charging electric vehicles.

How Customers Can Prepare for Potential Power Outages

Have a flashlight, radios, and fresh batteries ready. For more information on how to prepare for an emergency, visit PG&E’s Safety Action Center.

Use cooling centers to stay cool or during a power outage. Check with your city or county, or the Governor’s Office of Emergency Services list and map of cooling centers statewide.

Operate personal generators safely. Follow the owner’s manual and perform a visual inspection before starting or operating a generator. When setting up a generator, place it on a flat, stable surface to reduce the likelihood of it tipping over. To prevent carbon monoxide poisoning, never operate an engine-powered generator in an enclosed space or inside a house or a tent.

About PG&E

Pacific Gas and Electric Company, a subsidiary of PG&E Corporation (NYSE:PCG), is a combined natural gas and electric utility serving more than 16 million people across 70,000 square miles in Northern and Central California. For more information, visit pge.com and pge.com/news.