AUSTIN, Texas — Austin Energy’s Sand Hill Power Plant will soon be producing electricity again.
The 23-year-old plant has been down for routine maintenance. This time of year is part of what power experts refer to as “shoulder” months – less volatile periods when scheduled maintenance can take place.
The entire site is registered as a 595 megawatt capacity. U.S. Energy Information Administration data shows Sand Hill usually produces 100,000-200,000 megawatt hours each month.
August 2023 saw the largest output with 277,692 megawatt hours.
“After the summer run, because we all know that this summer was kind of brutal on the equipment we have, we have time that we take off to do maintenance on the equipment: the generators and the turbines. It's a lot like your car,” said Matt Kuffler, the plant manager for Sand Hill.
Kuffler said the maintenance months are shorter now.
“So, you know, five years ago, it wasn't that big a deal when we'd get to, say, the second half of September, everything would be kind of calmed down. There wouldn't be as much demand on the grid or at least not as much demand compared to how much supply there is available," Kuffler said. "Right now, because of the increased demand, because of the hot temperatures we've been seeing the last couple of years and because of the way that solar tails off at the end of the day, we're running into these periods that we find even into the end of September, we need to be able to run. So then it actually had an effect on when we can actually try to schedule these things."
City records show Sand Hill winter preparations include:
- Perform boiler and instrument air maintenance
- Perform electric heater, heat trace and dew point monitor maintenance
- Perform tarping/insulating of critical instrumentation and equipment
- Procure inventory/fuel as needed
- Conduct winter preparation training for plant personnel
- Install heat trace systems at power plants
- Insulate weather exposed critical components and add supplemental heating
- Inventory list added for ease of reordering supplies
- Satellite phone check with Real Time Desk and yearly battery replacement
- Winter weather preparation training
- Add additional areas for freeze protection as needed
“This piece behind me is called the heat recovery steam generator (HRSG),” Kuffler said, giving the KVUE Defenders and other members of the press a look at how the plant operates.
Most of the power plant site was off-limits, citing safety reasons.
“That is absolutely full of pipes that we run water through to turn into steam. And when I say it's full, I mean, if you stand inside there on this end and look that way, you can't even see daylight,” Kuffler said.
On the top of the HRSG sits three drums with equipment Kuffler says is sensitive to cold weather.
“We have some panels that go along the graded floor to keep there, to keep cold wind from coming up underneath,” Kuffler said.
Plastic walls surround the lower level serve as temporary windbreakers to be removed after the winter season.
The heat recovery steam generator makes up 175 megawatts of the Sand Hill’s 595 megawatt capacity.
“It's more challenging to get ready for winter than it is for summer, if you can believe that, because these units were designed when it was already hot in summer in Texas,” Kuffler said.
The plant remained operational during the deadly February 2021 winter storm, the freezing weather during December 2022 and the ice storm in February 2023.
Kuffler said more than a dozen employees lived inside the administration building for a week during the February 2021 storm.
“You'll note there's no bedrooms in there, right?” Kuffler said.
Kuffler said the management team will staff power plants according to the weather forecast. Someone must always be on site during a storm, he said.
“So when we would run into instances where, yes, we had alarms on sensors and that sort of thing, the guys in the control room would have to react to that. Is this real? Is there a way I can work around this to keep the unit running? And that's what it took,” Kuffler said.
In an after-action report following the February 2023 ice storm, Austin Energy said it would make sure a catering service procurement and coordination process was in place.
The KVUE Defenders reported how some power plants had trouble during some of those winter storms because the natural gas pressure coming to the plant dropped. Kuffler said they have more than one gas supplier to the area to minimize that risk.
“There’s a lower limit of pressure that we can operate to and our normal supply is well above that,” Kuffler said.
Kuffler recently signed an attestation to the winter readiness.
Under a requirement set by the Texas Legislature, power regulators and the power grid manager, Austin Energy’s General Manager, Bob Kahn, will also sign an attestation before the power plant can go back online.
Kuffler said all paperwork should be filed by the end of the week.