Boosted by new power plant capacity expected to be available by August, Texas should have adequate electricity supplies this summer, according to the state’s largest power grid, the Electric Reliability Council of Texas.
ERCOT issued its final summer outlook Thursday, saying the coming months are forecast to be milder than in the previous four years. ERCOT serves about 85 percent of the state’s total electricity demand and covers about 75 percent of the state.
It foresees peak demand of about 68,100 megawatts, just below the record 68,305 megawatts used Aug. 3, 2011, during that year’s heat wave. A megawatt of electricity is enough to serve about 200 Texas residences during a period of high demand, like a hot day when air conditioners are running.
The report estimates available resources of about 74,600 megawatts. But by Aug. 1 an additional 2,153 megawatts of capacity is expected to be available. “We may need to ask consumers to reduce electric use if we experience extremely hot weather or widespread unit outages during the early summer months,” said Warren Lasher, ERCOT’s director of system planning.
ERCOT also said it expects its reserve margin — the amount of available resources over forecast demand — to remain just above its 13.75 percent target through 2017. By August, the margin is expected to be 15.3 percent.
The Austin-based agency said it added two new power plants to its long-term schedule since February: a 299-megawatt wind farm expected to be in service in 2015, and a 703-megawatt gas-fired facility expected in 2016.
There have been concerns that low prices for electricity have discouraged generators from adding enough new capacity to keep up with growing demand. But ERCOT changed its forecasting assumptions earlier this year, with the result of a higher reserve margin.
That margin could go even higher if ERCOT changes the way it counts the state’s wind power capacity, which at more than 11,000 megawatts is the nation’s largest.
ERCOT historically has included only 8.7 percent of wind capacity in its capacity outlook, in recognition of wind’s intermittent output. But in March it called that figure “conservative” and said a new analysis shows that 14 percent of capacity can be expected from the West Texas wind farms and that coastal wind farms could operate at 27 percent.