Power to the people from dormant generating plant




Posted on August 3, 2011 at 11:15 PM

Updated Thursday, Aug 4 at 3:04 AM

With another day of record demand for electricity in Texas.. power companies are operating all available power plants — including older facilities not frequently used.

But in a critical situation like Wednesday's searing heat, they may make the difference when it comes to generating the power needed to keep your air conditioner running.

Luminant, the biggest power generator in Texas, operates one of those part-time plants at Lake Ray Hubbard, and News 8 was there as the pressure in the control room rose with the heat Wednesday.

ERCOT, the agency responsible for the grid providing power to most of Texas, needed all of the 40-year-old plant's 921 megawatts, and on this day, failure was not an option.

"It's vital that that unit be there, because we may find ourselves in a position where a unit here or there is the difference between meeting all the customer demand and having to interrupt customers," explained Luminant spokesman Scott Diermann.

Lake Hubbard is one of Luminant's seven "peaker" plants — older natural gas-fired facilities that often sit dormant, but are resurrected when demand is peaking.

Without peaker plants, the state power grid couldn't provide the margin to meet demand.

By mid-morning Wednesday, operators got the first unit going and began the 90-minute process lighting up the second unit's boiler.

"Think of a burner like on a gas grill," Diermann said. "This is his big gas grill adding burners to create the right temperature."

With steam at the proper temperature and pressure, operator Ricky Mason made the visual check to confirm the turbine was turning, powering the generator.

Then... with megawatts rising... operator Jay Vandergriff faced the tricky task of equalizing the plant's frequency with the grid.

With the match made Lake Hubbard's electricity — enough to power 200,000 homes — flowed into the grid.

With both units on, the challenge in this extreme heat is to make sure they stay on. Someone at the plant is constantly troubleshooting at the boiler where 16 burners fire flames to 2,800 degrees, and huge pumps propel water and steam through the boiler and cooling systems.

Operators check for leaks and and incorrect temperatures.

"Yes, everything is sensitive to heat," Diermann said. "This is designed for Texas summers, but this is an exceptional Texas summer, so everything is stressed."

Lake Hubbard was scheduled to be in operation until around midnight Wednesday, then shut down as operators wait for the next order likely on Thursday, when the heat — and the pressure to keep the Texas power grid humming — will be back on.

"If you're not there, then the customer suffers," Diermann said.

E-mail bwatson@wfaa.com