More power plant woes likely if Texas drought drags into winter

A number of Texas power plants may need to cut back operations or shut down completely if the state’s severe drought continues into the fall, an official with Texas’ main transmission manager told FuelFix.

At least one North Texas power plant has had to reduce how much it generates because the water level in its cooling reservoir has fallen significantly, said Kent Saathoff, vice president of system planning and operations for the Electric Reliability Council of Texas.

If the state’s drought continues for much longer and water levels continue falling at other power plant reservoirs, other units could be forced to curtail operations or shut-down completely, Saathoff said.

“Right now we don’t have a significant problem with it, but it could become one,” Saathoff said in an interview. “This has been the driest 12-month stretch we’ve seen in Texas in a long time.”

ERCOT has declared power emergencies several times this summer as record demand met a large number of unplanned power plant outages. Plant operators say the long hot summer has also meant more wear-and-tear due to longer operating hours for power plants.

On Aug. 4 the state came close to initiating rolling blackouts when the margin between power supply and demand grew too  thin. It would have been just the fourth time in 21 years the state would have taken such extreme measures.

ERCOT – which oversees the high voltages transmission system that connects 75 percent of the state, including most major cities – can call on industrial customers to cut about 1,500 megawatts of demand during emergencies.

And in a few cases there are programs where utilities are able to temporarily cut residential demand during peak hours – Austin Energy has been able to cut 35 to 45 megawatts of peak demand by cycling off air conditioners in about 90,000 homes twice per hour for 10 minutes.

But with those resources close to tapped out during recent peak demand days, ERCOT asked two power plant operators – Garland Power & Light and NRG Energy – to bring two power plants each out of mothballs to have available through the end of October.

Garland’s two 61 megawatt gas-fired units were online this week while the two NRG gas-fired units located on the Houston Ship Channel are expected to be ready by Sept. 1.

ERCOT may need to ask other power plant operators to bring other mothballed units back online this winter if the drought continues, Saathoff said.

“There’s another 2,000 megawatts of mothballed capacity we can call on, but it will take a couple of months for them to come back,” he said.

For the time being, that appears to be all ERCOT can do to deal with the drought, he said.

“The bottom line is there’s not much we can do absent rain,” Saathoff said. “Cooling reservoirs just aren’t being replenished.”