Exelon plant switches on lighting system for savings

Who does the electric company turn to when it wants to save energy?

Exelon Corporation is one of the nation’s largest energy companies, generating and distributing electricity to millions of customers in Illinois and Pennsylvania. When the company slated a renovation of its Fairless Hills, Pa., generating plant – including a 45-year-old lighting system – they called on Westinghouse Lighting Solutions (WLS) to provide a customized T5 fluorescent system that cut energy use by 80 percent and more than doubled light output to create a brighter, safer workplace.

Exelon’s Fairless Hills generating plant consists of a turbine hall and a maintenance shop. The turbine hall is a cavernous 14,000-square-foot room housing massive steam-powered turbine generators. The plans called for thoroughly renovating, painting and modernizing the space, including replacing an antiquated lighting system consisting of 44 1,000-watt incandescent fixtures and 10 400-watt high-pressure-sodium (HPS) fixtures. Exelon’s objectives were to bring the workspace up to the standards Exelon has set for all facilities.

An Exelon spokesperson said, “Our needs were to find a system that increased illumination while decreasing energy usage.” In particular, the lighting system had to be highly efficient and provide a better light environment for the plant operators and employees.

The Westinghouse customized design began with a site visit and lighting survey by WLS regional manager Ashutosh Atre. Based on his measurements and calculations, WLS proposed a one-for-one retrofit that would meet Exelon’s illumination requirements by replacing each existing fixture with a Westinghouse T5 High-Output Precision Optics fluorescent high-bay fixture.

“I assured Exelon our system would meet their foot-candle and energy-efficiency specifications,” Atre explained. “I was able to show them examples of a previous system we’d installed in a similar generating plant. Even so, I think they felt the numbers were almost too good to be true at first.”

Power consumption for the new system was calculated at 9.852 kilowatts (KW) per hour of operation as opposed to 48.65 KW per hour for the old system – a savings of 38.8 KW per hour, or 80 percent. Over a year of full-time operation, financial savings were projected at $33,988, assuming 10 cents per kilowatt-hour (kWh).   

Figure 1. The Exelon power plant before the lighting switch.

Westinghouse HY Series hybrid fixtures were specified to replace the old system of incandescent and HPS fixtures. After the turbine hall was renovated and painted, the new system was installed at a 40-foot mounting height. For general area lighting, 48 Westinghouse three-lamp HY Series fixtures were mounted in three evenly spaced rows down the length of the room. In addition, a four-lamp HY Series fixture was mounted at both ends of each row to provide additional light in the room corners and along the walls. Because the facility operates around the clock with 24/7 lighting, no special controls were needed.

After six months Exelon has found the Westinghouse system is exceeding the projected energy savings while significantly increasing light levels and visual acuity. The old fixtures were providing a gloomy 10 to 19 foot candles (FC) at the work surface. The new system delivers a bright 30 to 35 FC, consistent with recommended light levels. The new system also has a higher Color Rendering Index (CRI), which means that employees can see better, more comfortably and accurately on the job.

Figure 2. The Exelon power plant after the lighting switch

Jay Goodman, WLS managing director, believes the Exelon installation demonstrates an important point as American industry moves to address the challenges of global competitiveness and environmentalism: Facilities managers may be underestimating the savings they can achieve through lighting upgrades.
“The Westinghouse system cut Exelon’s monthly kilowatt hours by 80 percent, dramatically outperforming the common industry misconception that 50 percent savings is as good as it gets,” he said.

The environmental impacts of the Westinghouse system are considerable as well. By reducing Exelon’s annual energy usage by 339,888 kWh per year, it saves 168.97 tons of carbon dioxide (CO2) emissions annually as well, the equivalent of taking 28 cars off the road.

The energy savings and light increases provided by Westinghouse fixtures are primarily achieved through innovative “one-bounce-and-out” reflector design. Each reflector is engineered to maximize fixture efficiency and meet the light-distribution requirements of the specific application. Fixture efficiency indicates how well the fixture transmits light from the lamps to the workplace. Westinghouse optimizes reflector design by computer modeling the trajectories of millions of light rays within the fixture, then manufactures the reflectors to CNC tolerances of one 10,000th of an inch to provide fixture efficiencies of up to 96 percent. 

As a result, WLS high-efficiency fixtures reduce users’ overhead costs and quickly yield a measurable financial return.

“We view the overall performance of the Exelon system – six-month payback, light levels increased more than 200 percent, a deep reduction of their carbon footprint – as validation that Westinghouse Precision Optics make a better fixture, which in turn is a better investment for customers seeking improved lighting and energy efficiency,” said Goodman.

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