Powering up

CLECO’s new $1 billion power plant surges forward in central La.

By Angelle Bergeron

The Shaw Group Inc. of Baton Rouge plans to complete the $1 billion Cleco Power LLC’s Rodemacher Unit 3 power plant by June 2009. The facility near Boyce, La., will deliver more affordable, environmentally friendly energy to Louisiana customers.

Shaw’s engineering, procurement and construction contract to build the new 600MW electricity generating plant, originally valued at $680 million, stipulates delivery by September 2009.

The heart of the new plant is the circulating fluidized-bed technology, which can operate on multiple solid fuels and was developed under the U.S. Department of Energy’s clean-coal technology program. At the time of completion, the CFB unit will be the second largest in the country. The unit was designed by Foster Wheeler Ltd. of Clinton, N.J.

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The remainder of the plant, unloading dock on the Red River and conveyor system to deliver coal to the plant were designed by Shaw. The CFB contains two 330MW units that supply steam to a single steam turbine generator, says Bruce Davis, vice president of CFB coal for Shaw, Stone and Webster.

“These steam generators have a number of advantages,” Davis says. “Combustion temperatures in the furnace are lower than typical pulverized coal units, reducing nitrogen oxide emissions. Limestone injected in the furnace along with the fuel absorbs sulphur dioxide, reducing SO2 emissions.”

A state-of the-art pollution control polishing scrubber system will remove 98% of the sulphur, says Bill Fontenot, vice president of regulated generation development for Cleco.

Shaw also designed the plant with the flexibility to burn a variety of fuels without having to make capital changes in the plant.

“In a coal plant, fuel is typically 40-50% of the operating costs,” Davis says. “Having this flexibility gives Cleco a competitive advantage.”

Petroleum coke is the fuel of choice because it is a byproduct of the refinery business, which means the plant can draw from 14 sources in the Gulf Coast, Fontenot says. Additionally, the plant may operate on two other kinds of coal and lignite.

This is Shaw’s first CFB boiler,” says Gary Lawson, site construction manager. “The CFB must be built by steps. When we placed the second steam drum on June 29, that was a major milestone because you have to set that to release all the other activities.”

After site clearing was completed, Shaw installed the maze of underground circulating water piping and electric duct banks that must be completed before the foundations are poured. More than 5,000 yds of concrete were required for each boiler foundation.

“We had certain requirements in the summer to put ice in it to keep the concrete below specification temperatures,” Lawson says. “This foundation is 8 ft deep with tons of rebar in it, so we poured it in three sections.”

The design for the main boiler block is proprietary, but generally, it is about 200 ft tall, with a footprint 170 by 340 ft and requires an estimated 9,200 tons of steel, Lawson says.

Each of the steam drums is 81 ft long, more than 6 ft in diameter with 6-in. walls, and weighs more than 400,000 lbs., Lawson says. “We had to haul each one in on a transporter and use strand jacks and hydraulic lifts that lift them 20 ft per hour,” Larson adds.

Once the drums were placed, work began on installing the down-comers (piping), process lines and wall panels that will form the housing for the boiler furnace.

The contractor is using five cranes-a 2800, two 4100s and two 4600s-strategically situated around the perimeter of the boiler block. “Some are for reach, and some are for capacity,” Lawson says.

The table-top foundation for the STG required 1,000 yds of concrete and multiple inspections by different teams to ensure accurate placement of the embeds and anchor bolts, which only have a 1/8-in. tolerance. The STG building structure has about 1,000 tons of steel. In October, the 690,000-lb Hitachi Stator will be delivered.

“The manufacturer is under obligation to get it to the site,” Lawson says. “Heavy haul options are being reviewed.”

Currently, about 600 workers are onsite, but the project will require 1,100 to 1,200 by the end of the year or the first quarter of 2008, Lawson says. Obtaining sufficient labor hasn’t been a problem thus far, but with so much work ongoing in the region, that may become more of a challenge. 

“Craft availability for electricians, tube welders and boilermakers is a concern,” Lawson says. “It’s been a challenge to get the qualified workers to hang this kind of steel. It’s so large and heavy, and not everyone can do that.”

Because of the steel erection, the biggest safety issues on the project are fall protection and falling objects, says Richard Carter, Shaw’s onsite environmental, health and safety program manager. To support a safe environment, Shaw initiated a near-miss program in December that includes eight additional hours of intensive training on near miss reporting by a third-party company. 

By the end of July, Shaw reported one million work hours with no missed time, and, in celebration, the staff cooked for the entire crew. “I’m pleased and proud of the work the employees have done on this project,” Lawson says. “It’s a motivation that lets them know how much we all appreciate their hard work.”