Tri-Valley communities, like the rest of California, were left sweating on Tuesday evening but ultimately avoided rotating power outages thanks to successful conservation in the face of a record-breaking heat wave and the highest power grid peak demand in state history.
The California Independent System Operator declared an Energy Emergency Alert 3 for roughly three hours statewide, which set the stage for potential rolling blackouts to ease the strain on the state's power grid, but the final call never came as many residents and businesses heeded officials' requests and cut back just enough.
"At 8 p.m., the grid operator ended its Energy Emergency Alert (EEA) 3 with no load sheds for the night. Consumer conservation played a big part in protecting electric grid reliability. Thank you, California," CAISO officials said on Twitter on Tuesday night.
The heat wave boils on, likely until Friday according to current forecasts, and a statewide Flex Alert has been called again for 4-9 p.m. Wednesday (Sept. 7).
The week started with one of the hottest Labor Day Mondays for cities like Livermore, which experienced a record-breaking 116 degrees -- the previous record was 108 set in 1950. Pleasanton, Dublin and San Ramon all hit 113 degrees this week, according to different weather tracking websites.
Excessive heat warnings and advisories have been extended until Thursday at 8 p.m. Temperatures are expected to decrease slightly on Wednesday, before climbing again Thursday and ultimately dipping for good starting Friday. The weekend forecast currently projects highs between the 80s and 90 degrees.
With cities in the Tri-Valley eclipsing or getting close to 110-degree temperatures on Tuesday, residents were advised to limit their power usage in order to avoid potential rotating power outages. A similar call for conservation is in place for Wednesday with the Flex Alert.
The state's power grid has been closely monitored over the last few days as demand for electricity was expected to be at its highest-ever level, driven by a combination of the heat wave and people returning to work. The peak demand on Tuesday was 52,061 megawatts, an all-time high in California.
Elliot Mainzer, president of the CAISO, told consumers and businesses on Twitter to avoid using unnecessary energy to prevent these rotating outages, as electricity demand is forecasted to reach an all-time high on Tuesday.
According to the PG&E website, a rotating outage is an electric power outage that rotates from area to area, so no single neighborhood is down for very long. It's designed to reduce demand and maintain power grid reliability because brief outages protect against longer and larger outages.
CAISO, which oversees the operation of California's bulk electric power system, stated in a news release on Tuesday that if outages are initiated, residents would receive notifications from power providers on areas affected and time duration.
"Rotating power outages, or small-scale, contained, controlled interruptions in power, can help maintain reliability and avoid cascading blackouts," according to the news release.
These can occur when CAISO issues an Energy Emergency Alert 3 due to not being able to meet minimum contingency reserve requirements for electricity. An Alert 2 was already in place before the next level was issued late Tuesday evening. The Alert 3 order was rescinded at 8 p.m. Tuesday.
PG&E had already begun notifying about 525,000 customers to prepare for potential rotating outages in case they need to take place.
Power in the BART was also affected as major delays were experienced on the Berryessa and Dublin-Pleasanton lines in all directions due to trains traveling at reduced speeds to conserve energy.
For individual homes, officials recommend energy cutbacks during Flex Alerts such as setting the thermostat to 78 degrees (after pre-cooling the home at 72 degrees throughout the day), turning off unnecessary lights and not using large appliances from 4-9 p.m. when demands on the grid are often the highest.
But saving energy isn't the only thing residents should be aware of during the heat wave.
According to the National Weather Service, excessive heat can harm individuals in many ways including breathing problems, heat cramps, heat stroke, illness, and even death.
Heat becomes especially dangerous if it lingers for more than one day as hot days and warm nights don't give our bodies time to cool down.
Some ways to help is by wearing light, loose-fitting clothing and drinking water often. It is also recommended to avoid unnecessary hard work or activities if you are outside or in a building without air conditioning as air conditioning is the strongest protective factor against heat-related illness.
As a result of the continued heat, Dublin Unified School District announced on Twitter that schools will move to a minimum day schedule from Wednesday through Friday as a "proactive step." Students at Fallon Middle School were released early on Tuesday, just after 1 p.m., after the campus experienced a power outage.
Patrick Gannon, communication and community relations director for the Pleasanton Unified School District, told the Weekly that the district will not "cut into instructional time unless absolutely needed."
"Our goal is to keep students safe and learning in schools. We continue to monitor conditions, take precautions, and are making modifications to outdoor activities," Gannon said adding that Tuesday's sport practices and games were cancelled because of the extreme heat.
Below are some places that are offering cooling centers in the Tri-Valley during the heatwave:
Pleasanton Library - 400 Old Bernal Ave., Pleasanton, CA 94566
Dublin Senior Center - 7600 Amador Valley Blvd., Dublin, CA 94568
Livermore Public Library - 1188 S Livermore Ave., Livermore, CA 94550
Robert Livermore Community Center - 4444 East Ave., Livermore, CA 94550
Dougherty Station Library - Contra Costa County Library - 17017 Bollinger Canyon Road, San Ramon, CA 94582.