California ISO extends Flex Alert for today, 4-9 p.m.

September 9, 2022


California-ISO

Due to supply uncertainty, consumers are urged to conserve electricity

FOLSOM, Calif. – The California Independent System Operator (ISO) issued a statewide Flex Alert, a call for voluntary electricity conservation, for today, Sept. 9, from 4 p.m. to 9 p.m., due to a prolonged heat wave pushing up energy demand and tightening available power supplies.

The ISO also issued an Energy Emergency Alert (EEA) 1, effective today from 4 p.m. to 8 p.m., which signals that supply deficiencies are expected, and market participants are encouraged to offer more energy bids.

With above-normal temperatures continuing in the forecast across much of the state, the power grid operator is expecting high electricity demand, primarily from air conditioning use, and is calling for voluntary conservation steps to help balance supply and demand.

The Flex Alert is scheduled between 4 p.m. and 9 p.m., when the grid is most stressed from higher demand and less solar energy. During that time, consumers are urged to conserve power by setting thermostats to 78 degrees or higher, if health permits, avoiding use of major appliances and turning off unnecessary lights. 

To minimize discomfort and help with grid stability, consumers are also encouraged to pre-cool their homes and use major appliances before 4 p.m., when conservation begins to become most critical.

Reducing energy use during a Flex Alert can help stabilize the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California ISO extends Flex Alert to today from 3-10 p.m.

September 8, 2022


California-ISO

Heat, high projected loads, and lower solar output lead to supply uncertainty

FOLSOM, Calif. – The California Independent System Operator (ISO) has issued a statewide Flex Alert, a call for voluntary electricity conservation, for today from 3 p.m. to 10 p.m., due to continuing forecasted high demand on the grid and tight power supplies.

With above-normal temperatures in the forecast across much of the state, the power grid operator is expecting high electricity demand, primarily from air conditioning use, and is calling for voluntary conservation steps to help balance supply and demand.

The ISO also issued an Energy Emergency Alert (EEA) 1, effective today from 3 p.m. to 9 p.m., which signals that supply deficiencies are expected, and market participants are encouraged to offer more energy bids.

The Flex Alert is scheduled between 3 p.m. and 10 p.m., when the grid is most stressed from higher demand and less solar energy. During that time, consumers are urged to conserve power by setting thermostats to 78 degrees or higher, if health permits, avoiding use of major appliances and turning off unnecessary lights.

The Flex Alert hours have been extended for today because market deficiencies are projected during that time frame.

To minimize discomfort and help with grid stability, consumers are also encouraged to pre-cool their homes and use major appliances before 3 p.m.

Reducing energy use during a Flex Alert can help stabilize the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Energy Emergency Alert 2 declared to protect grid

September 7, 2022


California-ISO

Reducing energy use this evening will be key to preventing outages

FOLSOM, Calif. – The California Independent System Operator (ISO) has issued an Energy Emergency Alert (EEA) 2, effective today from 4 p.m. to 9 p.m.

The emergency alert has been declared to help the grid secure more supplies and urge market participants to lower demand on the system. The state and much of the West is enduring an historically long and record-breaking heat wave, straining the grid from high electricity use.

A Flex Alert is also in effect again for today, from 4 p.m. to 9 p.m. to help alleviate grid stress and avoid rotating power outages.

When the Flex Alert conservation period is in effect, consumers are urged to:

  • Set their thermostat to 78 degrees
  • Avoid using the oven, dishwasher, washer and dryer
  • Turn off unnecessary lights

To be as comfortable as possible during the Flex Alert hours, consumers are also encouraged to manage electricity use by taking these steps before 4 p.m. today:

  • Pre-cool your home by lowering the thermostat as low as 72 degrees
  • Use major appliances, like dishwashers, washers and dryers, and ovens
  • Adjust blinds and drapes to cover windows

To learn more about EEA designations, view the Emergency Notifications fact sheet.

For more information on grid conditions, view today’s video of Elliot Mainzer, the CEO of the ISO.

For the most up-to-date information on emergencies, follow grid conditions in real time on ISO’s Today’s Outlook, download the free ISO Today mobile app, and follow us on Twitter at @California_ISO.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Conditions on the grid becoming more strained as heat wave intensifies

September 5, 2022


California-ISO

Even greater reductions in energy use needed to maintain reliability

FOLSOM, Calif. – Record-breaking temperatures are leading to historic high forecasted demands for power, putting even greater strain on the California Independent System Operator (ISO) electrical grid and significantly increasing the likelihood of rotating outages unless consumers can reduce their energy use even more than they have so far.

“This is an extraordinary heat event we are experiencing, and the efforts by consumers to lean in and reduce their energy use after 4 p.m. are absolutely essential,” 

said Elliot Mainzer, the California Independent System Operator’s president and CEO.

“Over the last several days we have seen a positive impact on lowering demand because of everyone’s help, but now we need a reduction in energy use that is two or three times greater than what we’ve seen so far as this historic heat wave continues to intensify.”

The ISO declared an Energy Emergency Alert 1 (EEA) Monday morning from 5 to 9 p.m. today. That emergency designation signals to utilities and consumers that all resources are committed or forecasted to be in use, and that energy deficiencies are expected. A Flex Alert urging consumers to reduce their power use in the late afternoon and evening is also in effect today and tomorrow, marking seven consecutive days the call to cut demand has been issued.

As they monitor a host of factors including wildfires and generator availability, grid operators will determine later today if the emergency notifications need to be elevated to an EEA 2 or beyond.

EEA 2 would trigger deployment of a suite of emergency tools designed to keep supply and demand for the power system balanced during extreme conditions, and potentially freeing up to a few thousand megawatts of additional resources.

If conditions continue to deteriorate, an EEA 3 may be declared. If reserves are then exhausted the ISO would instruct utilities in its service area to manage shedding load.

Utilities make the determination of how best to spread and rotate the outages across for their service territory, with the goal of keeping them as short as possible. For two days in August 2020, outages affecting about 800,000 homes and businesses lasted anywhere from 15 minutes to about 2 ½ hours, marking the first time outages were ordered in California due to insufficient supplies in nearly 20 years.

“We never want to get to that point, of course,” Mainzer said, “but we want everyone to be prepared and understand what is at stake. We can’t control the weather, but we really can bend the demand curve and get through this successfully if everyone doubles down and reduces their energy use as much as possible.”

For more information, see our Rotating Power Outages fact sheet.

Forecasted loads are currently very high today and tomorrow, with Tuesday showing peak demand at 51,145 megawatts (MW), which would set a new record from the previous high of 50,270 MW in 2006. Wednesday’s load is forecast at 50,002 MW. For context, see our Peak Load History report.

The ISO is projecting supply deficiencies of 400 to 3,400 MW between the hours of 5 p.m. and 9 p.m. tomorrow.

Consumer and commercial demand response, including Flex Alerts, has been helping to extend tight resources over the past week, with a load reduction of around 1000 MW for each of the past several days, with more now needed as the heat continues to increase.

Before a Flex Alert takes effect, consumers are encouraged to pre-cool their homes and use major appliances earlier in the day, when solar supplies are abundant. Cooling homes in advance minimizes discomfort during the Flex Alert.

Reducing energy use during a Flex Alert can help protect the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages. Turning your thermostat to 78 degrees or higher, health permitting, not using major appliances such as your dishwasher or washing machine, and turning off all unnecessary lights are among the most effective ways to reduce residential energy use.

For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California faces worsening grid challenges on Monday and Tuesday

September 4, 2022


California-ISO

Demand for power approaching record levels; CAISO calls for even greater reductions in electricity use

FOLSOM, Calif. – With historic heat bearing down on California for the next several days and energy demand approaching record levels, the California Independent System Operator (ISO) is stepping up its call for consumers to lower electricity use in the afternoons and evenings to avoid outages.

“Starting tomorrow, this multi-day event is going to get much more intense,” said ISO President and CEO Elliot Mainzer. “We are facing a load forecast of 48,817 megawatts and energy deficits between 2,000 and 4,000 megawatts for Monday, resulting in the highest likelihood of rotating outages we have seen so far this summer.

“Because of the increasingly extreme conditons, we will need significant additional consumer demand reductions during the hours of 4 p.m. to 10 p.m. on Monday and access to all the emergency tools that the state and utilities have established for an extreme event like this one. We thank electricity consumers for their sustained effort to help us maintain reliability during these very difficult conditions.”

The ISO has issued a statewide Flex Alert, its sixth straight day calling for consumers to cut their electricity use, tomorrow from 4 p.m. to 10 p.m., when they are urged to set thermostats to 78 degrees or higher, avoid using major appliances, and turn off all unnecessary lights. A Flex Alert is also in effect today from 4 p.m. to 9 p.m.

The extra hour of reduced energy use is needed tomorrow because of projected market deficiencies through 10 p.m.

Additional calls for reducing energy consumption are expected as the state endures record-breaking temperatures lasting at least through Friday. The heat wave is historic for both its temperatures and its duration.

Heat advisories and excessive heat warnings are in place across the West, with daytime high temperatures forecast to be 10-20 degrees above normal.

Electricity customers’ actions to cut their demand have already resulted in an estimated 600 to 700-megawatt savings in recent days and are expected to be even more important and impactful through the next several days.

Power grid conditions are expected to be strained this evening, with a potential for supply shortfalls. However, Monday and Tuesday are still projected to be the most challenging days yet, with the highest temperatures forecast on Tuesday and projected electricity demand of 50,099 megawatts (MW). For a look at historical demand, see the ISO’s Peak Load History report.

The peak load yesterday was 44,123 MW, and the forecast for today is 45,776 MW.

Grid operators are closely monitoring wildfires for potential threats to generators and transmission wires, and fire officials have warned that more fires could break out in the coming days, due to the prolonged high heat and dry conditions.

Several generators are already out of service, making supplies tighter.

Consumer and commercial demand response, including Flex Alerts, has been helping to extend tight resources at critical hours so far this week.

The Flex Alert is scheduled between 4 p.m. and 9 p.m., when the grid is most stressed from higher demand and less solar energy on the system.. 

Consumers are also encouraged to pre-cool their homes and use major appliances before 4 p.m., when solar supplies are abundant. Cooling homes in advance minimizes discomfort during the Flex Alert and helps to stabilize the grid.

Reducing energy use during a Flex Alert can help protect the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert extended to Sunday, Sept. 4 due to high heat

September 3, 2022


California-ISO

Consumers are urged to conserve electricity from 4 to 9 p.m. to protect grid

FOLSOM, Calif. – As the state moves into the most intense heat of the summer, the California Independent System Operator (ISO) is preparing for challenging grid conditions over the next several days, and calling on Californians to lower electricity use during Flex Alerts.

A Flex Alert is in effect today from 4 to 9 p.m., when consumers are urged to set thermostats to 78 degrees or higher, avoid using major appliances, and turn off all unnecessary lights. Another Flex Alert has been issued for tomorrow, Sept. 4, also from 4 to 9 p.m.

Additional Flex Alerts will likely be called as heat will only intensify through Tuesday, with little relief from triple-digit temperatures seen over the next several days. Daytime high temperatures are forecast at 10-20 degrees above normal in much of the state through the Labor Day weekend and into next week, and record-breaking heat is projected in some parts of California.

Conditions are expected to be tight this evening, with a potential for supply shortfalls. Still, Sunday, Monday, and Tuesday in particular are shaping up to be the most difficult of this heat wave. Tuesday’s peak demand is forecast to be 50,087 megawatts (MW), just shy of the all-time record of 50,270 MW set in 2006. For more information, see the ISO’s Peak Load History report.

The peak load yesterday was 45,829 MW, and the forecast for today is about 45,000 MW.

Grid operators are closely monitoring three wildfires – Route Fire, Border 32 Fire, and the Mill Fire -- with varying threats to transmission lines. State fire officials have warned that more fires could break out in the coming days, adding to the risk of lost lines or generation.

Several generators have already been forced out of service, making supplies tighter.

Consumer and commercial demand response, including Flex Alerts, has been helping to ease strained conditions on the grid at critical hours so far this week, giving operators extra cushion in supplies.

Flex Alerts help alleviate stress on the grid in the late afternoon and evening when solar production rolls off the system, and demand remains high.

Consumers are also encouraged to pre-cool their homes and use major appliances before the start of Flex Alert at 4 p.m.

Reducing energy use during a Flex Alert can help stabilize the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert issued for tomorrow, Saturday, September 3

September 2, 2022


California-ISO

Call for consumer conservation extended to fourth consecutive day

FOLSOM, Calif. – The California Independent System Operator (ISO) has issued another statewide Flex Alert, calling for voluntary electricity conservation for tomorrow, Saturday, Sept. 3 from 4 p.m. to 9 p.m., due to increasing high heat, tightening energy supplies and more potential strain on the grid.

A Flex Alert is also in effect today from 4 p.m. to 9 p.m., when Californians are strongly urged to lower electricity use by setting thermostats to 78 or higher, health permitting, avoid using major appliances, and turning off all unnecessary lights. Tomorrow’s Flex Alert is the fourth consecutive call for conservation, as much of the state remains gripped in an extensive heat wave.

With increased heat in the forecast for California and the West, the power grid operator is again expecting high electricity demand throughout Labor Day weekend and into next week, primarily from air conditioning use. With resources potentially very tight for tomorrow, conservation is crucial in helping to balance supply and demand.

The Flex Alert is scheduled between 4 p.m. and 9 p.m., when the grid is most stressed from high demand and less solar energy on the system.

Premiminary data show that consumer and business conservation during those hours has been helpful in keeping the grid stable so far this week, so the ISO is again urging Californians to moderate their electricity use as much as possible.

To minimize discomfort and help with grid stability, consumers are also encouraged to pre-cool their homes and use major appliances before 4 p.m., when solar energy is typically abundant.

Reducing energy use during a Flex Alert can help stabilize the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Intensifying heat leads to another conservation call

September 1, 2022


California-ISO

Flex Alert extended to a third consecutive day to help balance electrical grid

FOLSOM, Calif. – For the third straight day, high heat and heightened demand for electricity has resulted in the California Independent System Operator (ISO) issuing a statewide call for voluntary electricity conservation. The most recent Flex Alert has been issued for tomorrow, Friday, Sept. 2., from 4 p.m. to 9 p.m.

With triple-digit temperatures in much of California and the West, the power grid operator is again expecting high electricity demand, primarily from air conditioning use, and needs voluntary conservation steps to help balance supply and demand.

Flex Alerts have been resulting in some helpful conservation and grid operators and an emergency proclamation from Gov. Gavin Newsom, requested by the ISO, has also freed up some additional resources.

A Restricted Maintenance Operations (RMO) remains in place through Tuesday, Sept. 6, each day from noon to 10 p.m. The declaration orders market participants to avoid any scheduled routine maintenance during those times to ensure all available resources are in service. View the Emergency Notifications fact sheet for more information.

The Flex Alert covers that time of day when the grid is most stressed from higher demand and less solar energy. During that time, consumers are urged to conserve power by setting thermostats to 78 degrees or higher, if health permits, avoiding use of major appliances and turning off unnecessary lights. 

To minimize discomfort and help with grid stability, consumers are also encouraged to pre-cool their homes and use major appliances and charge electric vehicles and electronic devices before 4 p.m., when conservation begins to become most critical.

Reducing energy use during a Flex Alert can help stabilize the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to find more electricity conservation tips, visit the ISO’s Flex Alert website.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California ISO extends Flex Alert to Thursday, Sept. 1

August 31, 2022


California-ISO

Extreme heat continues urgent need to conserve electricity from 4 to 9 p.m.

FOLSOM, Calif. – The California Independent System Operator (ISO) has extended its statewide Flex Alert, calling for a second consecutive day of voluntary electricity conservation tomorrow, Thursday, Sept. 1, from 4 to 9 p.m., due to continuing extreme temperatures pushing up energy demand and tightening available power supplies.

With excessive heat in the forecast across much of the state and Western U.S., the grid operator is again expecting high electricity demand, primarily from air conditioning use, and is calling for the public to conserve as much electricity as possible from 4 to 9 p.m.

This is in addition to today’s Flex Alert, which is also in effect 4 to 9 p.m.

Additional Flex Alerts could be issued through the Labor Day weekend as triple-digit temperatures are forecast across much of California and the West.

In what’s likely to be the most extensive heat wave so far in the West this year, temperatures in Northern California are expected to be 10-20 degrees warmer than normal through Tuesday, Sept. 6. In Southern California, temperatures are expected to be 10-18 degrees warmer than normal. A majority of weather stations in California’s interior are poised to break their respective daily records over the holiday weekend, with the chance of monthly records being broken at a handful of stations.

The Flex Alert for Thursday, Sept. 1 is scheduled for 4 p.m. to 9 p.m., when the grid is most stressed from higher demand and less solar energy. During that time, consumers are urged to conserve power by setting thermostats to 78 degrees or higher, if health permits, avoiding use of major appliances and turning off unnecessary lights. They should also avoid charging electric vehicles while the Flex Alert is in effect. 

To minimize discomfort and help with grid stability, consumers are also encouraged to pre-cool their homes and use major appliances and charge electric vehicles and electronic devices before 4 p.m., when conservation begins to become most critical.

Reducing energy use during a Flex Alert can help stabilize the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California ISO issues Flex Alert for today, Aug. 31

August 31, 2022


California-ISO

Extreme heat triggers urgent need to conserve electricity from 4 to 9 p.m.

FOLSOM, Calif. – The California Independent System Operator (ISO) has issued a statewide Flex Alert, a call for voluntary electricity conservation, for today, Aug. 31 from 4 p.m. to 9 p.m., due to high temperatures pushing up energy demand and tightening available power supplies.

With excessive heat in the forecast across much of the state and Western U.S., the grid operator is expecting high electricity demand, primarily from air conditioning use, and is calling for voluntary conservation steps to help balance supply and demand.

Additional Flex Alerts are also possible through the Labor Day weekend as record-setting temperatures are forecast across much of the West.

In what’s likely to be the most extensive heat wave so far in the West this year, temperatures in Northern California are expected to be 10-20 degrees warmer than normal through Tuesday, Sept. 6. In Southern California, temperatures are expected to be 10-18 degrees warmer than normal. Death Valley is currently forecast to peak at 126 degrees on Saturday, which would tie the highest temperature ever recorded on Earth in the month of September.

Today’s Flex Alert is scheduled between 4 p.m. and 9 p.m., when the grid is most stressed from higher demand and less solar energy. During that time, consumers are urged to conserve power by setting thermostats to 78 degrees or higher, if health permits, avoiding use of major appliances and turning off unnecessary lights. They should also avoid charging electric vehicles while the Flex Alert is in effect. 

To minimize discomfort and help with grid stability, consumers are also encouraged to pre-cool their homes and use major appliances and charge electric vehicles and electronic devices before 4 p.m., when conservation begins to become most critical.

Reducing energy use during a Flex Alert can help stabilize the power grid during tight supply conditions and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to find more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California ISO issues Flex Alert for tomorrow, Aug. 17

August 16, 2022


California-ISO

High heat expected; consumers urged to reduce energy use to protect grid

FOLSOM, Calif. – The California Independent System Operator (ISO) has issued a statewide Flex Alert, a call for voluntary electricity conservation, for tomorrow, Aug. 17, from 4 p.m. to 9 p.m., due to predicted high temperatures pushing up energy demand and tightening available power supplies.

With above-normal temperatures in the forecast across much of the state tomorrow, the power grid operator is expecting an increase in electricity demand, primarily from air conditioning use, and is calling for voluntary conservation steps to help balance supply and demand.

Consumers are urged to conserve electricity, especially during the late afternoon and early evening, when the grid is most stressed due to higher demand and less solar energy.

Reducing energy use during a Flex Alert can help stabilize the power grid during a time of tight supply conditions, and prevent further emergency measures, including power outages.

For information on Flex Alerts, and to get more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert extended through tomorrow due to widespread heat in West

September 08, 2021


California-ISO

Consumers urged to reduce energy use from 4-9 p.m. to relieve grid stress

FOLSOM, Calif. – The California Independent System Operator (ISO) has extended a statewide Flex Alert for a second day, issuing a call for voluntary electricity conservation for tomorrow, Sept. 9, from 4 p.m. to 9 p.m., because of hot weather affecting much of California and the West, and tight energy supply margins in the market.

Tomorrow’s Flex Alert follows today’s conservation call, also due to above-normal temperatures in the western states. Consumers are urged to conserve electricity from 4 p.m. to 9 p.m. on both days by setting their thermostats to 78 degrees or higher, and deferring use of major appliances and unnecessary lights during that time.

The ISO also issued a system-wide Restricted Maintenance Operations (RMO) order for today and Thursday from noon to 9 p.m., delaying routine maintenance of generation and transmission equipment so that all available resources are online for the critical evening time.

The Flex Alerts have been issued due to above-normal temperatures leading to high electricity demand in California and parts of the western US, narrow margins of supply, and cloud cover creating uncertainty for renewable generation forecasts.

Temperatures in the Northern California inland region are forecast to be 3-10 degrees warmer than normal. In Southern California, temperatures are expected to be 5-10 degrees warmer than normal through the weekend, primarily for the interior, although coastal regions are forecast to see some warming as well.

Above-normal temperatures throughout much of the interior western US are also expected this week, with some cities seeing a potential for record-breaking heat. Widespread heat waves affecting other western states limits the California ISO’s ability to import energy from neighboring power grids.

The ISO is predicting an increase in electricity demand, primarily from air conditioning use. The increase can stretch electricity supplies thin and cause strain on our power grid, especially in the late afternoon and evening, when solar production goes offline and wind generation is uncertain, however, temperatures and electricity demand remains high.

Consumers are urged to conserve electricity, especially during the late afternoon and early evening, when the grid is most stressed due to higher demand and solar energy production falling.

Reducing energy use during a Flex Alert can help stabilize the power grid during a time of tight supply conditions, and prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to get more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert issued for Wednesday due to heat and tight power supply

September 07, 2021


California-ISO

Consumers urged to reduce energy use from 4-9 p.m. to protect grid reliability

FOLSOM, Calif. – The California Independent System Operator (ISO) has issued a statewide Flex Alert calling for voluntary electricity conservation Wednesday, Sept. 8, from 4 p.m. to 9 p.m., due to predicted high energy demand and tight supplies on the power grid.

With above-normal temperatures in the forecast for much of California and the West, the power grid operator is predicting an increase in electricity demand, primarily from air conditioning use. The increased demand can make electricity supplies tight and strain the power grid, making conservation essential.

During the Flex Alert time period, consumers are asked to lower their thermostats to 78 degrees or higher, if health permits, and take other voluntary measures that include avoiding the use of major appliances and unnecessary lights.

To take full advantage of all available supply, the ISO has also issued a restricted maintenance operation (RMO) for tomorrow from noon to 9 p.m., notifying ISO participants to avoid taking grid assets offline for routine maintenance until the RMO is lifted.

Conserving electricity during the late afternoon and early evening is crucial because that is when the grid is most stressed due to higher demand and declining solar energy production.

In the past, reducing energy use during a Flex Alert has helped operators keep the power grid stable during tight supply conditions and prevented further emergency measures, including rotating power outages.

For information on Flex Alerts, and to get more electricity conservation tips, visit FlexAlert.org.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
    • Washer and dryer
    • Dishwasher
    • Oven and stove for pre-cooking and preparing meals
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert issued for tomorrow, due to heat and tight supply

July 27, 2021


California-ISO

Consumers urged to reduce energy use from 4-9 p.m. to protect grid reliability

FOLSOM, Calif. – The California Independent System Operator (ISO) has issued a statewide Flex Alert, a call for voluntary electricity conservation, for tomorrow, Wednesday, July 28 from 4 p.m. to 9 p.m., due to predicted high energy demand and tight supplies across the West.

With higher than normal temperatures in the forecast for parts of interior Northern California, the power grid operator is predicting an increase in electricity demand, primarily from air conditioning use. The increase can make electricity supplies tight and cause strain on our power grid.

Consumers are urged to conserve electricity, especially during the late afternoon and early evening, when the grid is most stressed due to higher demand and solar energy production falling. Consumers are also asked to turn off unnecessary lights, delay using major appliances until after 9 p.m., and set air conditioner thermostats to 78 degrees or higher, if health permits.

The conservation measures can help stabilize the power grid during a time of tight demand and supply, and avoid power interruptions. Reduced electricity use during a Flex Alert can prevent further emergency measures, including rotating power outages.

Tips before a Flex Alert:

  • Pre-cool home by setting the thermostat to as low as 72 degrees
  • Use major appliances:
  • washer and dryer - do laundry
  • oven and stove - pre-cook and prep meals
  • run the dishwasher
  • Adjust blinds and drapes to cover windows

Tips during a Flex Alert from 4 p.m. to 9 p.m.:

  • Set thermostat to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures.

Follow developing grid conditions at the ISO’s News webpage, under the System Conditions Bulletin, or follow us on Twitter at @California_ISO.

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California ISO Issues Flex Alert for Monday, July 12 due to wildfires, heat

July 11, 2021


California-ISO

Consumers asked to conserve energy tomorrow from 4 p.m. to 9 p.m.

FOLSOM, Calif. – With electric transmission lines from Oregon still unreliable due to the explosive Bootleg Fire and continued high temperatures across the West resulting in increased demand for electricity, the California Independent System Operator (ISO) issued a statewide Flex Alert for Monday, July 12 to help stabilize the state’s electric grid and deal with uncertainty created by the extraordinary conditions.

Consumers are strongly encouraged to continue to conserve as much electricity as possible between 4 p.m. and 9 p.m. Monday. Conservation is key to reducing stress on the grid during these peak hours.

In addition, the ISO issued a Restricted Maintenance Operations (RMO) for Monday that requires generators to postpone any planned outages for routine equipment maintenance, ensuring that all available resources can be dispatched to the grid.

The fast-moving Bootleg Fire tripped off transmission lines on Friday and again Saturday, limiting electricity flow from the Pacific Northwest to California and other states. Power supplies to the California ISO service territory, which covers about 80 percent of the state, have been reduced by as much as 3,500 megawatts because of the fire.

Yesterday, Governor Gavin Newsom signed an executive order to quickly secure additional power that has helped maintain grid stability through the weekend. The executive order remains in place.

When a Flex Alert is in effect, consumers are strongly encouraged to take these specific actions from 4-9 pm:

  • Set thermostats to 78 degrees or higher, if your health permits
  • Avoid using major appliances, like dish washers and clothes washers and dryers
  • Turn off all unnecessary lights

Earlier in the day, before the Flex Alert takes effect and when solar energy is abundant, consumers are encouraged to take these steps to be comfortable and help grid operators balance electricity supply and demand: 

  • Pre-cool your home by lowering the thermostat
  • If you need to use your major appliances, do it before the Flex Alert is in effect, when solar energy is plentiful
  • Close window coverings to keep your home or apartment cool
  • Charge electronic devices and electric vehicles so there’s no need to do it later, when solar generation is down

If demand still outstrip supply after a Flex Alert is in effect, the ISO could take the infrequent step of ordering California utilities to spread power outages of relatively short duration to effectively extend available electricity as much as possible.

As California’s ability to store solar and wind energy with batteries or other technology continues to improve, those crucial evening hours will be less of a challenge and similar emergencies rarer. But for now, collective action to conserve is our most effective way to keep the grid stable.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert extended to Saturday: conservation needed from 4 p.m. to 9 p.m.

July 10, 2021


California-ISO

Electric grid strained due to high heat and fire-threatened transmission lines

FOLSOM, Calif. – A rapidly growing wildfire in Southern Oregon that is threatening transmission lines used to import energy to California, along with continued extreme heat throughout the state, are putting new stresses on the electric grid, making the need for strong conservation much more critical.

The California ISO has extended a statewide Flex Alert for a second consecutive day (Saturday, July 10) and is strongly encouraging consumers to conserve as much electricity as possible from 4 p.m. to 9 p.m. to help keep the grid stable. Successful conservation when the grid is under such duress can alleviate the need for rotating outages that could be taken as a last resort when demand for power continues to outstrip supply.

Conditions on the electric grid were already a challenge Friday, when much of California was experiencing triple-digit temperatures, some generating capacity was not available and a Flex Alert was called for the late afternoon and evening.

ISO data show demand for electricity did start to drop once Friday’s Flex Alert was in effect and consumer conservation began to take hold. But conditions deteriorated quickly as the Bootleg Fire continued to grow and posed an imminent threat to transmission lines leading into the California Oregon Intertie (COI).

The COI is not only used to import electricity from the Pacific Northwest to the electric grid managed by the ISO, it also imports power into other grid balancing authorities and the state of Nevada.

The fire has been a wildcard for grid operators since it began Tuesday in rural Klamath County reportedly from a lightning strike. The wind-driven blaze, which has forced evacuations and is not projected to be contained for another two weeks, had burned a little less than 40,000 acres by Friday, nearly doubling in size from the day before. By Saturday morning, it had nearly doubled in size again and burned more than 76,000 acres.

On Friday afternoon, the ISO issued a formal Grid Warning, which gives the grid operator authority to initiative emergency demand response programs that compensate electricity customers for conserving. That Warning was canceled at 10 p.m. Friday, about the time demand for electricity is typically low, but could be reinstated today if conditions warrant.

Conservation is the best tool to quickly bring down demand on the grid, and when the Flex Alert is in effect again today between 4 p.m. and 9 p.m., consumers are strongly encouraged to conserve energy by:

  • Setting thermostats to 78 degrees or higher, if health permits
  • Avoiding using major appliances
  • Turning off all unnecessary lights

Consumers are also encouraged to use fans for cooling and unplug unused electrical items.

Earlier today, before the Flex Alert takes effect at 4 p.m. and when solar energy is abundant, consumers are encouraged to take these steps to be comfortable and help grid operators balance electricity supply and demand: 

  • Pre-cool your home by lowering the thermostat
  • If you need to use your major appliances, do it before the Flex Alert is in effect, when solar energy is plentiful
  • Close window coverings to keep your home or apartment cool
  • Charge electronic devices and electric vehicles so there’s no need to do it later, when solar generation is down

Voluntary conservation has helped keep the electric grid stable during past times of high stress on the grid, including last month when triple-digit temperatures across the West strained the system with higher demand for power.

In addition to Flex Alerts, the ISO is using multiple tools to help keep the grid stable, including a solicitation on July 1 to generators in the Western region to procure additional resources.

The ISO is also working with business and industry to help them reduce electricity consumption at critical times. And on Saturday, the ISO issued an order that requires generators and transmission operators to postpone any planned outages for routine equipment maintenance, ensuring all grid assets are available for use

Grid operators continue to closely monitor conditions and will have additional announcements as needed.

As California’s ability to store solar and wind energy with batteries or other technology continues to advance, crucial evening hours will be less of a challenge and similar emergencies rarer. But for now, collective action to conserve is our most effective way to support grid reliability.

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California ISO extends Flex Alert a second day through Saturday

July 9, 2021


California-ISO

Voluntary conservation and other actions taken to support grid reliability

FOLSOM, Calif. – The California Independent System Operator (ISO) has extended a statewide Flex Alert for a second day to avoid a possible shortage of energy as extreme heat in California and a growing wildfire in Southern Oregon threatening transmission lines continue to strain the state’s electric grid. 

When the Flex Alert is in effect again between 4 p.m. and 9 p.m. on Saturday, July 10, consumers are strongly encouraged to conserve energy by:

  • Setting thermostats to 78 degrees or higher, if health permits
  • Avoiding using major appliances
  • Turning off all unnecessary lights

Consumers are also encouraged to use fans for cooling and unplug unused electrical items.

Earlier in the day, before the Flex Alert takes effect and when solar energy is abundant, consumers are encouraged to take these steps to be comfortable and help grid operators balance electricity supply and demand: 

  • Pre-cool your home by lowering the thermostat
  • If you need to use your major appliances, do it before the Flex Alert is in effect, when solar energy is plentiful
  • Close window coverings to keep your home or apartment cool
  • Charge electronic devices and electric vehicles so there’s no need to do it later, when solar generation is down

In addition to the Flex Alert, the ISO is using multiple tools to help keep the grid stable, including a solicitation on July 1 to generators in the Western region to procure additional resources. The ISO is also working with business and industry to help them reduce electricity consumption at critical times.

Conditions on the grid became more challenging Friday afternoon when the rapidly expanding Bootleg wildfire in southern Oregon was threatening electric transmission lines, putting limits on the amount of energy that can be imported to California.

Voluntary conservation has helped keep the electric grid stable during past times of high stress on the grid, including last month when triple-digit temperatures across the West strained the system with higher demand for power.

Grid operators continue to closely monitor conditions and will have additional announcements as needed.

As California’s ability to store solar and wind energy with batteries or other technology continues to advance, crucial evening hours will be less of a challenge and similar emergencies rarer. But for now, collective action to conserve is our most effective way to support grid reliability.

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California ISO issues Flex Alert for today; takes other steps to reduce grid stress

July 9, 2021


California-ISO

Actions taken due to extreme heat and potential shortfall of power

FOLSOM, Calif. – With extreme heat forecasted across much of California into early next week, the ISO is using multiple tools, including a Flex Alert encouraging voluntary conservation, to maintain a safe and reliable grid.

In addition to the Flex Alert asking consumers to conserve between 4 p.m. and 9 p.m. today, July 9, the ISO has other steps it can take to reduce demand or access additional capacity to manage the grid and avoid potential shortages during evening hours when demand remains high, primarily from widespread air conditioning use.
On July 1, for example, the ISO solicited bids to secure additional capacity within California and the Western region. The grid operator is also working with business and industry to help them reduce energy use at critical times.

Voluntary conservation has helped keep the electric grid stable during past times of increased stress on the grid, including last month when high temperatures across the West strained the system with higher demand for power.

While the Flex Alert is in effect on Friday from 4 p.m. to 9 p.m., consumers are asked to:

  • Set thermostats to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

To be as comfortable as possible during the Flex Alert hours, consumers are also strongly encouraged to take these steps earlier in the day:

  • Pre-cool your home by lowering the thermostat
  • Close window coverings to keep your home or apartment cool
  • If you need to use major appliances like your dishwasher, clothes washer and dryer, do so before the Flex Alert takes effect
  • Pre-charge electronic devices Close window coverings to keep your home or apartment cool
  • Pre-charge electric vehicles

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

California ISO Issues a Flex Alert for Friday, July 9 due to extreme heat, high demand

July 8, 2021


California-ISO

Consumers asked to conserve energy tomorrow from 4 to 9 p.m.

FOLSOM, Calif. – The California Independent System Operator (ISO) issued a statewide Flex Alert for Friday, July 9, citing extreme temperatures across much of California and a potential capacity shortfall on the state’s electric grid.

As a result of higher load, and supply forecasted to be tighter than expected on Friday, consumers are asked to voluntarily conserve electricity from 4 p.m. to 9 p.m. Such conservation would help ease the strain on the grid during the crucial evening hours when solar energy is diminished or no longer available.

When Flex Alerts were called in mid-June and during last summer’s regional heat wave in August and September, consumers answered the call and collectively made a significant reduction in their energy use. That allowed grid operators to avoid or limit possible rotating power outages that can become necessary when demand for electricity outstrips capacity.

While the Flex Alert is in effect on Friday from 4 p.m. to 9 p.m., consumers are asked to:

  • Set thermostats to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

To be as comfortable as possible during the Flex Alert hours, consumers are also strongly encouraged to take these steps earlier in the day:

  • Pre-cool your home by lowering the thermostat
  • Close window coverings to keep your home or apartment cool
  • If you need to use major appliances like your dishwasher, clothes washer and dryer, do so before the Flex Alert takes effect
  • Pre-charge electronic devices Close window coverings to keep your home or apartment cool
  • Pre-charge electric vehicles

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

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Flex Alerts

Monitor grid conditions on Today's Outlook

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A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Second day of Flex Alert is 6 p.m. to 9 p.m. today

June 18, 2021


California-ISO

More conservation sought to help balance energy supply and demand

FOLSOM, Calif. – Day 2 of the Flex Alert called by the California Independent System Operator (ISO) is from 6 p.m. to 9 p.m. Friday, as grid operators again ask the public to conserve electricity to help balance supply and demand on the grid and avoid service disruptions due to extreme heat across much of the Southwest.

Consumers have been responding to the conservation call, reducing electricity demand during crucial evening hours to keep from overtaxing supply while addressing the need for rotating power outages.

Elliot Mainzer, the ISO’s president and chief executive officer, thanked Californians for cutting back their electricity usage Thursday evening and also expressed gratitude to Gov. Gavin Newsom for issuing an emergency proclamation to free up additional generating capacity.

While the Flex Alert is in effect on Friday from 6 p.m. to 9 p.m., consumers are asked to:

  • Set thermostats to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

To be as comfortable as possible during the Flex Alert hours, consumers are also strongly encouraged to take these steps earlier in the day:

  • Pre-cool your home by lowering the thermostat
  • Close window coverings to keep your home or apartment cool
  • If you need to use major appliances like your dishwasher, clothes washer and dryer, do so before the Flex Alert takes effect
  • Pre-charge electronic devices Close window coverings to keep your home or apartment cool
  • Pre-charge electric vehicles

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are
subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions
and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert extended a second day through Friday

June 17, 2021


California-ISO

Consumers asked to conserve today and tomorrow due to extreme heat

FOLSOM, Calif. – The California Independent System Operator (ISO) has extended its Flex Alert a second day to Friday, asking consumers to again conserve electricity during the evening as California and states across the country work to relieve stress on electric grids due to extreme heat.

Consumers are asked to conserve energy tonight and tomorrow evening by:

  • Setting thermostats to 78 degrees or higher, if health permits
  • Avoiding using major appliances
  • Turning off all unnecessary lights

Consumers are also encouraged to use fans for cooling, and to unplug unused electrical items. Additional tips can be found at the website, Flex Alert.org, where people can also sign up to receive Flex Alert notifications.

To be as comfortable as possible during the Flex Alert hours, consumers can take these steps earlier in the day:

  • Pre-cool your home by lowering the thermostat
  • Use major appliances, like your dishwasher, and clothes washer and dryer
  • Close window coverings to keep your home or apartment cool
  • Charge electronic devices
  • Charge electric vehicles

The ISO is continuing to monitor weather and grid conditions and will have additional announcements as information becomes available. The grid operator had already called a Flex Alert for today, Thursday, from 5 p.m. to 10 p.m. Precise hours for a Flex Alert depend on hourly demand and supply forecasts and can change as conditions warrant.

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are
subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions
and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert in effect today from 5 p.m. to 10 p.m.

June 17, 2021


California-ISO

Voluntary conservation encouraged to keep grid stable during extreme heat

FOLSOM, Calif. – The California Independent System Operator’s (ISO) first Flex Alert of the year takes effect this afternoon, with consumers encouraged to voluntarily conserve electricity from 5 p.m. to 10 p.m. to help maintain grid stability while California and much of the Southwest experience triple-digit temperatures the next several days.

Once the Flex Alert conservation period begins, consumers are asked to:

  • Set thermostats to 78 degrees or higher, if health permits
  • Avoid using major appliances
  • Turn off all unnecessary lights

Consumers are also encouraged to use fans for cooling and unplug unused electrical items. Additional tips can be found at the website, Flex Alert.org, where people can also sign up to receive Flex Alert notifications.

To be as comfortable as possible during the Flex Alert hours, consumers are also encouraged to manage electricity use by taking these steps before 5 p.m. today:

  • Pre-cool your home by lowering the thermostat
  • Use major appliances, like your dishwasher, and clothes washer and dryer
  • Close window coverings to keep your home or apartment cool
  • Charge electronic devices
  • Charge electric vehicles

In a conference call with reporters yesterday, Elliot Mainzer, president and chief executive officer of the ISO, said the Flex Alert was being called “in a preponderance of caution” because demand and supply forecasts for today show a relatively modest shortfall of about 300 megawatts (MW) of electricity available to the grid. Grid operators believe voluntary conservation should close the gap, making the likelihood of rotating outages remote.

“We certainly know from experience, including last August and September, that Californians can make a huge difference in helping maintain overall grid stability by taking these very straight-forward and pragmatic steps to help conserve,” Mainzer told reporters.

Today is expected to be the hottest day of the week in Northern California, with high temperatures forecasted to reach between 100 and 110 degrees. Heat warnings continue to be in effect for much of Southern California, and states across much of the Southwest are experiencing similar temperatures and stress on their electric grids.

When past Flex Alerts have been called, consumers have answered the call and cut back their electricity use. Those actions have helped California avoid or limit power outages that can, if conditions persist or worsen, become necessary when demand for electricity outstrips capacity.

While typically set from 4 p.m. to 9 p.m., the precise time for the Flex Alerts varies depending on hourly projections of supply and demand. Grid operators said the 5 p.m. to 10 p.m. period will be the most challenging time for the electric system today based on those projections.

The ISO continues to closely monitor weather and grid conditions and will report later today whether a Flex Alert is also needed on Friday.

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are
subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions
and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

ISO issues Flex Alert for energy conservation tomorrow

June 16, 2021


California-ISO

Extreme heat forecast; consumer help will be key to preventing outages

FOLSOM, Calif. – The California Independent System Operator (ISO), with extreme heat forecast for much of California and the Southwest, has issued a statewide Flex Alert to encourage electricity conservation tomorrow from 5 p.m. to 10 p.m. to reduce stress on the grid and avoid power outages.

When past Flex Alerts have been called, consumers have answered the call and cut back their electricity use. Those actions have helped California avoid or limit power outages that can, if conditions persist or worsen, become necessary when demand for electricity outstrips capacity.

“The public’s help is essential when extreme weather or other factors beyond our control put undue stress on the electric grid,” said Elliot Mainzer, president and chief executive officer of the ISO. “We have seen the huge impact that occurs when consumers pitch in and limit their energy use. Their cooperation can really make a difference.”

While Flex Alerts are normally 4 p.m. to 9 p.m., the hours of conservation for this event are 5 p.m. to 10 p.m. due to operational needs. The statewide call for conservation is critical because when temperatures hit triple digits across a wide geographic area, no state has enough energy available to meet all the heightened demand, primarily due to air conditioning use.

For the next several days, much of California and the Southwest are expected to see triple-digit heat with above normal temperatures spread more broadly across much of the Western United States. And like California, other Western states – including Arizona and New Mexico – are experiencing similar stressful grid conditions due to the extreme heat.

Under such conditions, evening is the most difficult time of day for grid operations, especially in persistent hot weather when evening temperatures stay warm, because demand for electricity remains high as solar energy diminishes.

By collectively taking a few simple actions, electricity use can be reduced enough to keep power on for everyone. Last August and September, for instance, Californians heeded multiple Flex Alerts and Gov. Gavin Newsom’s call for a concerted response to emergency condition and reduced electricity use by 1,000 to 3,000 megawatts. That is enough electricity to power up to 3 million homes, and the conservation likely prevented subsequent and more severe rotating outages last August and September.

If demand still outstrips supply after Flex Alerts and other measures are taken, the ISO could again order utilities to begin rotating power outages. That would extend available power supplies and guard against longer and more extensive disruptions while protecting high-voltage transmission lines from damage.

As California’s ability to store solar and wind energy with batteries or other technology continues to increase, the crucial evening hours will be less challenging. But for now, concerted action to conserve is our most effective way of keeping the grid working for everyone.

Before a Flex Alert is in effect, consumers can take specific steps to manage their electricity usage to maintain comfort during days that conservation is needed. Specifically, consumers can:

  • Pre-cool your home by lowering the thermostat
  • Use major appliances, like your dishwasher, and clothes washer and dryer
  • Close window coverings to keep your home or apartment cool
  • Charge electronic devices
  • Charge electric vehicles

From 5 p.m. to 10 p.m. tomorrow, when the statewide Flex Alert is in effect, consumers can help by:

  • Setting your thermostat to 78 degrees or higher, if health permits
  • Avoiding the use of major appliances
  • Turning off all unnecessary lights
  • Using fans for cooling
  • Unplugging unused items

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are
subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions
and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.

Flex Alert issued for today, calling for statewide energy conservation

October 15, 2020


California-ISO

Power grid operator predicts high heat and increased demand for electricity

FOLSOM, Calif. – The California Independent System Operator (ISO) has issued a statewide Flex Alert, a call for voluntary electricity conservation, from 3 p.m. to 10 p.m. today.

With hot temperatures in the forecast, the power grid operator is predicting higher than normal electricity demand today, primarily from air conditioning use. Heat advisories continue to blanket the Southern California coast and parts of the Northern California Bay Area region. Temperatures statewide are forecast to be up to 15-25 degrees above normal for this time of the year today and tomorrow.

Wildfires also are a concern to the reliability of the grid, as red flag warnings are in effect for much of Northern California through Friday morning. Fire can cause outages on transmission lines delivering electricity to homes and businesses. Currently no wildfires are directly threatening high-voltage lines, and the ISO is monitoring developments closely and coordinating with fire strike teams throughout the state.

The ISO yesterday issued a Grid Alert, which notifies market participants of a projected shortfall in supply in the day-ahead energy market. A Restricted Maintenance Order (RMO) was also issued to restore any generation that may have been offline for routine scheduled maintenance.

The Flex Alert is being called to help with capacity gaps in the system, and is unrelated to the Public Safety Power Shutoffs, the de-energization of transmission lines ordered by utilities to mitigate localized wildfire risk. Those shutoffs, implemented by power providers, are currently having no effect on the bulk electric system.

Find out more about the PSPS programs at PrepareForPowerDown.com and check with local utilities for affected neighborhoods and times. To learn about the ISO's role during a PSPS, visit the ISO's News webpage and view the fact sheet.

Consumers are urged to conserve electricity, especially during the late afternoon and early evening, when the grid is most stressed due to higher demand and solar energy production falling.

The conservation measures can help the power grid during a time of tight demand and supply, and avoid power interruptions. Energy reduction during a Flex Alert can prevent further emergency measures, including rotating power outages.

For information on Flex Alerts, and to get more electricity conservation tips, visit the ISO's Flex Alert website.

  • Before 3 p.m., "pre-cool" buildings by setting air conditioning thermostats lower than usual; also, charge electronic devices and electric vehicles; and run dishwashers, washers and dryers and other major appliances.
  • After 3 p.m., set thermostat at 78° or higher
  • Cool with fans and draw drapes
  • Turn off unnecessary lights and defer use of appliances

For information on Flex Alerts, to get more electricity conservation tips, and to sign up for conservation alerts, visit the ISO's Flex Alert website. Visit the ISO's News page for more information on the heat wave's impacts on grid operations, and to learn more about alerts, warnings and emergency notices.

For updates on grid operations, follow us on Twitter at @California_ISO or @FlexAlert, or monitor system conditions in real time at ISO's Today's Outlook.

Sign up for
Flex Alerts

Monitor grid conditions on Today's Outlook

Download 
ISO Today app

A Flex Alert is issued by the ISO when the electricity grid is under stress because of generation or transmission outages, or from persistent hot temperatures. Glossary of terms and acronyms

Click here to learn more about System Alerts, Warnings and Emergencies. Follow grid conditions in real time at ISO’s Today’s Outlook, or download the free ISO Today mobile app.

This advisory is based on the best data available at the time of its release. Grid conditions can change rapidly and are
subject to change without warning. This forecast is accepted by the recipient on the condition that errors, omissions
and/or changes to the contents shall not be made the basis for any claim, demand or cause of action against the California ISO.