Distribution Center Flipped The Switch In September On LED Tube Lights
This article is the first in a series that focuses on the retrofit DATA for LED tube lights specifically for professionals inside the illumination industry. The increasing focus on the LED tube lights has created interest in the specific numbers regarding retrofits such as this one.
On a sunny September morning in Metro New York, an 87-year-old family-owned business celebrated the comprehensive retrofit of their facility with LED tube lights that now places them soundly in the history books of the American Energy Revolution. The historical significance is based on three factors: #1) The massive scale of the project, #2) The new benchmark in low watts per sq. ft. and #3) The first “net zero” cost of lighting facility with Solar and LED tube lights.
The Facility: Davis & Warshow (www.dwny.com) is New York’s premier dealer of luxury kitchen and bath fixtures and plumbing materials. The company has a legacy of “Green” leadership and has recently converted its entire 209,000-square-foot Queens headquarters from fluorescent to LED tube lights.
#1) The massive scale of the project: Davis & Warshow has 11,352 linear feet of LED tube lights installed. This adds up to 2.15 Miles of tubes. (For the international LED tube lights professionals reading this article, the conversion is 3.44 kilometers). For further context, the replacement of fluorescent tubes with LED tubes adds up to about 38 Football Fields of light end to end. There may have been larger orders of LED tube lights for networks of multiple buildings across a chain or organization, but Davis & Warshow appears to stand to date as the largest single facility LED tube retrofit in U.S. history…if not the largest across the global market.
#2: The new benchmark in low watts per sq. ft.: The existing Davis & Warshow lighting primarily included 8’ T12 fluorescent tubes at 65 watts each. Each tube covered an area that was about 150 sq. ft. averaging about .4 watts per sq. ft. As a cross check on the data, the existing 8’ fluorescent tubes at 65 Watts = 8.125 watts per linear foot. With 11,352 total linear feet x 8.125 watts per linear foot there were 92,235 total pre-retrofit watts across the facility. 92,235 total existing watts divided by 209,000 sq. ft. = .44 Watts per sq. ft. for lighting. By contrast, the LED tube lights use 30 watts instead of 65 watts along the 8’ tubes. The energy consumption is just 3.75 watts for linear foot instead of the existing 8.125 watts. Across the 11,352 sq. ft. facility, the total consumption with the new LED tube lights is 42,570 watts divided by the 209,000 sq. ft. facility yields .203 or just a hare over .2 watts per sq. ft.
The ASHRAE Benchmark for Distribution Centers/Warehouses is .8 watts per sq. ft. By retrofitting with LED tube lights, that use less than half of the wattage of fluorescent tubes, Davis & Warshow has brought their lighting consumption down to just .2 watts per sq. ft. The facility uses about 25% of the cost of a typical U.S. Distribution Center, Warehouse or Industrial Facility. Davis & Warshow has set a new standard for efficiency in industrial facility lighting.
#3) The first “net zero” cost of lighting with Solar and LED tube lights: Davis & Warshow has 1,038 rooftop Solar Photovoltaic (PV) panels that were installed in 2010. The System Size is 238.74 kilowatts (kW) with Annual Energy Output of 268,574 kilowatt-hours (kWh). The Annual kWh produced by the Solar PV panels is 308,736 to 322,800 (the range is subject to sky conditions). The Monthly kWh produced by the Solar PV panels is 25,728. The Annual kWh to operate the LED tube lights is 157,525. The Monthly kWh to operate the LED tube lights is 13,127. The Solar PV system produces more than enough power to illuminate the facility given the energy efficient LED tube lights, and accordingly yields a “net zero” cost of illumination.