Unit 5 Generator Goes ‘From Worst to First’
At Lakeland Electric, Generator 5 was once synonymous with frustration, failure and even fire. It was considered a $165 million mistake.
Lakeland Electric's Unit 5 generator.
But Unit 5, the utility’s big, 360-megawatt combined cycle natural gas generator, has done a U-turn. It has gone from the outhouse to the penthouse among Lakeland Electric’s fleet of generators.
“Unit 5 has gone from worst to first,” said Tony Candales, a utility assistant general manager whose main job is to see that Lakeland Electric’s generators hum along.
That’s just what Unit 5 is doing, and it has been for more than a year. At one point during the past year, it worked continuously for 82 days.
In the 2009 fiscal year, which ended Sept. 30, Unit 5 was unavailable for service because of mechanical failure for just five days. That is by far the best performance since it went online in 2002.
The worst year for failure was 2006, when it was down with mechanical problems for 81 days.
It’s not unusual for generators to take a while to operate properly. But Unit 5, which was serial No. 1 of it’s kind, and it took longer than most and had a variety of problems, including:
The generator three times caught fire as Lakeland Electric and its manufacturer, Siemens, tried in vain to get it rolling at the turn of the century.
In summer 2005, Unit 5 went down for a few months with a rusted, broken rotor bolt. The cost to repair it and buy replacement power was $7 million.
In 2006, it was down for a month because a rotor blade went awry and damaged hundreds of other blades. The blades were a bit out of whack, and that problem was magnified by the high-speed at which the rotors spin. The blades had to be redesigned.
In 2008, insulation wore off thousands of copper wire windings. The wire is used to create a magnetic field, one of the essential elements of producing electricity. The fix was $2.5 million.
At one point, Candales said, things were so iffy with Unit 5 that workers used to cross their fingers when they fired it up.
It was always something.
Candales said that rather than fixing problems in the generator on a case-by-case basis, Unit 5 needed a two-month time out, during which a head-to-toe analysis of the machine - and how it was used - was undertaken.
With new wiring, better rotors, a two dehumidifiers to prevent rusting and a better understanding of the generator, it has been on a roll for more than a year. Lakeland Electric now makes every effort to keep Unit 5 running or shut down, rather than stopping and starting it repeatedly.
Candales praises Lakeland Electric power plant workers also for the success of Unit 5.
Mayor-elect Gow Fields said the earlier problems and eventual first-string status of Unit 5 remind him of the same thing Lakeland Electric went through with Unit 3, its 365-megawatt coal-fired generator.
The difference between Unit 3 and 5 is that Orlando owns 40 percent of Unit 3 while Lakeland Electric owns all of Unit 5.
“The two situations, early on, were a lot alike,” Fields said. “Both machines were considered dogs at one point in time.”