Summer Reserve Capacity Is Up But It Still Could Be a Dicey Summer: ERCOT Report

May 8, 2019



The return of a gas-fired unit and increased renewable output will raise resource capacity in the Texas electric system but because of unexpected increases in demand for power there is still a possible need for emergency actions this summer, according to the latest assessment report from the Electric Reliability Council of Texas (ERCOT).

Emergency actions would include requesting customers to conserve electricity, firing up backup power sources and importing power from other regions — “more likely” on a few occasions this summer, but mandatory power cutbacks such as rotating outages would only be a last resort.

Such actions can’t be forecast because, of course, it depends on just how hot it gets this summer.

ERCOT identified quickly-growing industries such as West Texas oil & gas and facilities building along the coast as particularly power-thirsty, with a system-wide growth rate expected to be between 2.5% and 3% as the year continues.

The council is seeing an increase in demand of about West Texas alone.

The report released on Wednesday is the final assessment before the summer season kicks in, during which a record forecast peak demand of 74,853 MW is expected, 1,300 MW (about 2%) higher than the all-time record set on July 19 of last year.

Operating reserves will remain tight, the Seasonal Assessment of Resource Adequacy report noted, but since its last report ERCOT, which manages about 90% of Texas electricity, has seen 733 MW of installed wind and solar capacity approved for commercial operations, with summer peak capacity contributions of 333 MW.

That in addition to an expected return to operation of a 365 MW gas-fired unit along with increased output from certain units that are undergoing equipment upgrades and an increase in the amount of DC tie imports increases the reserve electricity margin to 8.6%, up from the December estimate of summer reserves.

“ERCOT is prepared to use the tools and procedures that are in place to maintain system reliability during tight conditions,” said ERCOT President and CEO Bill Magness.

Looking ahead to next year, though, an expected increase in capacity from potential wind and solar projects should add to reserve capacity, easing the tight margins, with a more normal 10.5% reserve margin projected for summer 2020.