Rollin’ Blackouts

on June 17, 2011 at 9:30 AM


Record heat waves across the US this summer could force businesses and homes to use more electricity, potentially straining power grids.

But state electricity grid operators ranging from California to Texas said they have enough power on hand to meet the demands of peak usage during the summer months.

Heating Up Texas

Texas has forecast a summer peak demand of 63,898 MW, which is nearly 2,000 MW less than 2010. Last August, the state reached a record-breaking peak demand of 65,776 MW.

“We continually monitor expected temperatures and electricity demand forecast to ensure there is enough generation online to cover the load,” Dottie Roark, spokeswoman for the Electric Reliability Council of Texas (ERCOT), told Breaking Energy.

With an ample reserve margin of nearly 18%, ERCOT, which manages 85% of the state’s electric load, said it is ready this summer to handle the demands of 23 million people despite the record breaking temperatures.

Rolling blackouts are unusual in Texas, with only three of them occurring since 1989 and none of them taking place during the summer, said Roark.

However, the state has 1,484 MW of contractually committed demand response resources and emergency interruptible loads which can be used for emergency power shortages, she said.

Chris Brewster, an attorney who represents cities in Texas in ERCOT’s stakeholder process, told Breaking Energy the responsibility lies with the power generation industry to be prepared to provide adequate power for the summer months ahead since Texas is in the midst of a remarkable drought and heat wave.

“I am aware of the reserve margin that ERCOT has stated,” he said. “Although it does appear sufficient, Texas has recorded a number of days in excess of 100 degrees already. Cities throughout the state depend on ERCOT to prepare for the summer peak and we rely on ERCOT in conjunction with the power generation industry to be prepared.”

Power generators have felt the pressure from consumers and since last summer have added an additional 1,000 MW of generation to the Texas grid, including new and refurbished resources from gas units.

California Sweltering

California’s is well equipped for the summer with peak demand forecasted to rise by only 1.5% from 2010, Stephanie McCorkle, spokeswoman for the California Independent System Operator Corporation (ISO), told Breaking Energy.

The peak for the grid is expected to reach 47,814 megawatts (MW), which is 687 MW more than the actual peak of 47,127 MW set in 2010.

McCorkle was far from worried about the increased demand and instead said that she saw it as a sign of economic recovery.

“There is a slight increase in demand this summer,” she said. “The demand in the power grid is a barometer of the economy. It’s good news. The economy is starting to expand again.

Unlike other states, California experienced a very wet winter and has several new power plants operating, including a sizable addition in electricity coming from the wind sector, McCorkle said.

The California Independent System Operating estimates that the probability of rotating power outages is less than 1% and the state’s operating reserve margins are forecast to be over the 15% resource adequacy requirements created by state utility regulators. An estimated 2,357 MW of demand response and interruptible load programs can be deployed this summer.

“The supply is adequate this summer to handle just about any situation that may come up,” she said. “We also have an amazing snow pack level of 100%.” The snow pack levels keep hydroelectric facilities well-supplied.

NYC: Drop It Like It’s Hot

New York is expecting usage this summer will be two percent lower than last summer’s peak of 33,452 MW. Last summer’s peak in July marked the state’s third highest system peak.

Initiatives for energy efficiency, such as the ones from Mayor Bloomberg’s C40 Cities: Climate Leadership Group, have lowered the amount of electricity consumption, said the New York Independent System Operator (NYISO).

Picture: A darkened neighborhood on the edge of Mission Valley is silhouetted against the lights of a lit neighborhood area during a rolling blackout in San Diego, CA, March 19, 2001, which was hit for the first time since the begining of a state-wide power crisis. The rolling blackouts, which darkened 500,000 homes for one to six hours at a time, were orchestrated by the California Independent Operator’s System (ISO), which monitors the state’s power grid, because of warm weather, a higher power demand, and lack of electricity from the Northwest dropping reserves to less than one-and-one-half percent. (Photo by David McNew/Newsmaker