Peek behind Georgia Power's giant grid

At his computer beneath what looks like a massive, computerized Etch-a-Sketch on the wall, Greg Smith can see power demand swell as Georgians return to hot homes from work and begin flipping switches.

“My job is to make sure the state of Georgia’s lights stay on,” says Smith.

The huge screen in this room at Georgia Power headquarters is a view of the state’s transmission system, the giant electric superhighways that move power from its generators around the state. The arrows show the power rushing along them, much of it headed this way late Thursday afternoon.

Smith is the power system coordinator for Georgia, the chief air traffic controller for power flowing across the grid, part of a 15-person team that few outside the company think about unless something goes wrong. Part troubleshooters, part conductors, their job is to keep the power pathways open, no matter what happens here or in other states across the Southeast, no matter what the temperature. They do it 12 hours a day, changing places at sunrise and again at sunset.

Last week marked the summer’s first string of muggy, 90 degree-plus days in metro Atlanta, days punctuated by afternoon lightning storms and nights that never quite got cool. It’s when we use power the most, and when Georgia Power’s massive generation, transmission and distribution system, serving about 2.3 million customers in all but four of Georgia’s 159 counties, is put through its paces.

The utility’s system wasn’t perfect last week. Largely because of storms, roughly 26,000 metro area residents, most in north Fulton County, residents lost power at some point, with outages lasting between 15 minutes and four hours.

But overall the system worked, in part because of Greg Smith and the crew in the glass room.

Voltage veterans

Smith isn’t an engineer. He and transmission center supervisor Jerry West both laugh when asked about their credentials. “Me and Jerry have doctorate degrees in Georgia Power,” Smith says.

Both joined the company more than three decades ago, not long after high school. Both started in power plants. Both have been working to keep the company’s transmission system stable for more than decade, and display an easy mastery of what makes that happen.

While their focus is on Georgia, both still vividly recall the day in 2003 that a massive blackout hit the Northeast. They remember seeing it show up on their own monitors, hundreds of miles from the trouble. It was a quick, weird change in the voltage on Georgia’s transmission lines, a blip.

“It was like, ‘What is that?’ ” says Smith. “Later, we found out.”

Smith’s job includes knowing what’s happening in the Southeast beyond the four-state power system operated by Georgia Power parent Southern Co. A problem on a transmission line in Florida or Tennessee can affect how power flows in Georgia. So he is on the phone at least daily with Duke Power, the Tennessee Valley Authority, and Florida’s two non-Southern Co. utilities, trolling for problems for which Georgia’s system will have to adjust.

Throughout the transmission center, operators run risk scenarios, puzzling out what could happen if one line or another fails.

‘You need to send more’

When things heat up outside, they do in the glass room too.

Preparations for a heat wave begin days in advance, Smith said. Preventive maintenance gets done ahead if possible. When the heat and the storms hit, maintenance essentially goes on hold. The company needs its transmission lines live.

Decisions about how much power Georgia will get, meanwhile, are made days ahead, in Birmingham. That’s where Southern Co. schedules plant deployment, based on which of the system’s plants are the least expensive to use.

It’s Smith’s job to argue for more power if he thinks it’s needed.

“They look at the economics,” Smith says of Birmingham. But sometimes, he says, “We tell them: You need to send more.”

When a heat wave arrives, as it did this past week, demand from air conditioners, lights, computers, TVs, cellphones and clocks will suck electricity toward it automatically and with increasing intensity. Transmission operators have to clear the path.

They watch for overloads. Surging demand can pack too much voltage on transmission lines, which can make them sag dangerously close to the ground. And days of hot weather can wear on equipment unable to cool.

Heat plus lightning is even worse. The Georgia Power crew monitors that threat on a multi-colored lightning map that charts every bolt headed for Georgia and its intensity.

Just now, many in the room have noticed a lightning-rich storm marching in from Cartersville. In a few hours, it will cut off power in a portion of Cobb County, though it will cause no problems on the larger transmission system.

On the green-arrowed wall screen in front of Smith, faint pink dots show a line near Savannah beginning to carry too much power. If the pink turns red, Smith will get on the computer and phone and adjust things, forcing the power to find another route.

Meanwhile, a monitor in front of West’s crew shows a bank of red transmission lines as team members work the phones. “It means the voltage is high,” says West. “That’s what happens in the summer.”

The nightmare scenario — short of a Northeast-scale blackout — is a brownout, in which the power company “sheds load,” temporarily cutting off the juice to a rotating series of neighborhoods and businesses to keep voltage on its transmission system stable.

So far, it has never happened in Georgia, Smith says. “It hasn’t happened anywhere in the Southern system.”

Bending time

By 4 p.m. Thursday, with the temperature at 92 degrees, power demand in the state and metro Atlanta appears to have reached its peak, where it will stay for while.

Before they leave for the day, Smith and West will see us turn on our lights. The next shift will watch us turn them off again.

“We can tell when people come home,” Smith says. “I know when you get up in the morning. I know when you go to sleep.”

Those of us outside the glass room aren’t likely to notice the demand put on the transmission system, unless, of course, the power goes out.

But, says Smith: Watch your clocks. A really hot day can drain a full minute of time from an electric clock.

But don’t worry. Georgia Power puts the minute back while you sleep.

Peaking power demand

On Monday of this past week, Georgia Power electricity demand hit its highest point since 2008. The next two days weren’t far behind (demand for Thursday and Friday were not yet available):

Monday, June 14: 16,507 kilowatt hours

Tuesday, June 15: 16,505 kh

Wednesday, June 16: 16,495 kh

All-time peak demand: 17,987 kh (Aug. 9, 2007)

Last highest demand: 17,271 kh (Aug. 6, 2008)

Source: Georgia Power