Green Manufacturer - March April 2012

ergy costs generally are reduced by six to seven times, and replacing fluorescent with LEDs reduces energy costs by two to three times.

Our LED installation is maintenance-free. We expect this to continue for 20 to 30 years. My expectations have been exceeded in that electrical personnel no longer need to replace fluorescent bulbs with lifespans that are predictably very short.

This is by far the largest energy breakthrough since the incandescent light bulb.

Smith, Cooper Lighting. The answer is complex and depends on the application and the light levels needed.

If the application can take advantage of the optical control characteristics of LEDs, the user may drastically cut the number of LEDs required to provide adequate light levels, which significantly reduces energy consumption.

Cold-storage applications that have ambient temperatures of - 30 degrees C would consume less power than the same product installed in 20-degrees-C ambient because of LED’s higher efficiencies stemming from lower forward voltage from the cold temperature. The use of controls would extend the life while reducing energy; however, the installed costs would be higher to deploy the controls. So, the answer is multifaceted.

Roller, Cree. 40 to 75 Percent Energy Reduction. Against incumbent lighting technologies of metal halide, linear fluorescent, and HPS, facility managers can expect to achieve between 40 and 60 percent energy reduction using LED lighting. In a warehouse, even greater savings can be obtained by using occupancy sensors, which can further cut energy consumption in half for a total reduction of 75 percent.

LED lighting can cost more upfront than antiquated lighting technologies— but the ongoing energy savings and

“The LED option has
about a 12 times better
maintenance cycle and a
40 percent lower power
consumption with virtu-
ally unlimited life.”

— William Busch, Philips Day-Brite

maintenance avoidance can quickly recoup these costs and deliver additional savings.

Ford, Osram Sylvania. The LED fixture cost and energy consumption are dependent on the application.

Savings at Two Times Price Point. If the price point of an LED fixture is no more than two times the cost of a traditional lighting fixture typically used, then it may be an economically feasible option.

Ceramic metal halide fixtures with bilevel electronic ballasts are another alternative if a single lamp fixture is preferred, but look for a high-efficiency fixture. In addition, some high-bay fixtures with 200-W ceramic metal halide lamps on electronic ballasts can replace up to a 400-W metal halide fixture. Both the 4-lamp T5HO and single-lamp, 200- W ceramic metal halide fixtures reduce energy consumption by approximately 50 percent compared to a 400-W metal halide fixture.

By taking advantage of utility rebates, users can dramatically reduce the cost to install LED fixtures.

Low Maintenance Helps Bottom Line. The long life of an LED lighting system has additional benefits for the bottom line because less frequent lighting maintenance is needed, minimizing costly manufacturing downtime to replace lamps. This should be factored into the total cost of ownership calculations.

Spencer, Lusio. Low Total Cost of

Ownership. When considering a move to LEDs for general illumination, companies should consider several factors in addition to energy savings. These include a long product lifetime; low maintenance requirements; the ability to use occupancy sensors; dimming capabilities; and no heat gain—all of which contribute to an accurate assessment of the cost of ownership of any lighting system.

Kaminski, Waldmann Lighting.

Savings in Low or No Maintenance. Although LEDs do realize some energy conservation, the majority of cost savings comes from low or no maintenance, which allows for continuous manufacturing without downtime to fix lighting and associated labor costs.

Busch, Philips Day-Brite. 40 Percent Lower Power Consumption.

Each application is different as required light levels vary by the application or task being performed. The commonly used HID luminaire in a manufacturing application, a 400-W probe-start metal halide high-bay, has a power consumption of 460 W. The lamp has an L70 of 8,000 hours and an average rated life of 20,000 hours.

A typical LED high-bay that can produce the same light levels as this 400- W unit has a power consumption of 288 W, an L70 of 100,000 hours, and an average rated life that far exceeds 100,000 hours, because LEDs do not burn out like metal halide lamps do.

This says that the LED option has about a 12 times better maintenance cycle and a 40 percent lower power consumption with virtually unlimited life. The user can expect to pay a much higher cost for an LED luminaire, but will realize a reduced total cost of ownership compared to a traditional metal halide system.