(CNN)The Electric Reliability Council of Texas (ERCOT), the organization that operates much of the Lone Star State's electric grid, asked residents for a second day in a row Tuesday to conserve as much energy as possible until Friday.
Electric grid operator asks Texans to stop blasting AC as unplanned outages and heat collide
The strain on the grid stems from record-high demand for electricity amid increasing summer heat and a higher than usual number of forced outages at power plants, the organization said.
"When ERCOT issued a call for conservation on Monday, Texans responded strongly by reducing electric demand during the late afternoon. ERCOT continues to encourage Texans to conserve power each afternoon during the peak hours of 3 to 7 p.m. through this Friday," a news release by ERCOT read.
"ERCOT has been leveraging every resource at its disposal, including activating all available generating units to help serve customer demand before calling for conservation. Approximately 1,200 MW of power was regained overnight Monday when some repairs were completed. One MW typically powers around 200 homes on a summer day."
ERCOT said Monday that energy generator owners have reported about 11,000 MegaWatts of generation are on forced outage for repairs, including about 8,000 MW of thermal energy. That's significantly higher than on a typical hot summer day, when the range of thermal generation outages is about 3,600 MW, the organization said.
"We will be conducting a thorough analysis with generation owners to determine why so many units are out of service," said ERCOT Vice President of Grid Planning and Operations Woody Rickerson. "This is unusual for this early in the summer season."
Wind output was also expected to be lower than usual on Mounday, but the output was expected to increase as the week moved on, ERCOT said.
While the system's energy capacity is lower, ERCOT customers have simultaneously been using record amounts of energy to cool their homes. According to the release, ERCOT has set a new June record for electricity demand.
"Based on preliminary data, the new record is 69,943 MW, which exceeds the 2018 June record by approximately 820 MW," the release said. "Power plant owners continue repairs of unexpected equipment failures, and ERCOT is using all the tools in its toolbox to maintain reliability in the face of potential record-setting electricity demand."
The National Weather Service of Fort Worth warned of a hot day Tuesday with temperatures forecast to be in the mid to upper 90s. The heat wave is expected to last through Friday.
ERCOT said last month that it anticipated record-breaking electric demand this summer due to hot and dry conditions and economic and population growth in the region. That trend is likely to continue in future years as human-caused climate change drives more extreme heat waves in Texas. A 2020 report from the Texas state climatologist concluded the number of 100-degree days there will double by 2036.
ERCOT asked Texas residents to set their thermostat to 78 degrees or higher; turn off lights and pool pumps and avoid using large appliances; and turn off and unplug unused electric items.
The advice is altogether similar to California's recommendations last summer during its own heat wave. At the time, US Sen. Ted Cruz, Republican of Texas, attacked California's conservation pleas as representative of a "train wreck of an energy policy."
"It's hot everywhere—try Texas every summertime—but the rest of the country doesn't have such a dysfunctional state govt that you can't turn the lights on or run A/C. That's a policy failure of the Dems," he said then.
The strain on the electric grid this week comes four months after ERCOT suffered catastrophic system failures during an extensive winter storm in February. The abnormally cold weather froze wind turbines, sharply limited natural gas supplies and slammed coal and nuclear energy plants, while it also caused a spike in customer demand for heating.
The issues pushed ERCOT to shut down power for millions of people for days on end, causing more than 100 deaths, the majority of which were due to hypothermia. Afterward, five ERCOT board members resigned and its CEO was fired.
Texas, America's leading energy producer, relies on its own electric grid separate from the two major grids that serve the rest of the US. Energy demand typically peaks in the late afternoon and early evening, according to ERCOT's forecasts.
After February's winter storm, energy experts and the state's Republican politicians noted that the system was set up to handle the hottest days of summer rather than frigid winter storms. Now that, too, is being put to the test.