Conversion of Cortelco Facility, Corinth, MS

Cortelco occupies a 77,000 square foot facility that is broken down as: 15,000 square feet of office space, 12,000 square feet of manufacturing/assembly space, and a 50,000 square foot warehouse. As part of our decision to become a distributor of LED products, we felt that we should undertake the conversion of all of the indoor and outdoor lighting of various types that had previously been used to LED. Not only would we be able to benefit from the savings that resulted but also we gained the experience in selecting the best LED alternatives based upon light output, cost, and ease of installation. The 15,000 square feet of office space was broken down further into 12,000 square feet of general office space and 3.000 square feet of lab space. These areas have a 9 foot suspended ceiling with 2’ X 2’ white, acoustic tiles. Combined these two areas were lit by a total of (220) 2 X 4’ fluorescent fixtures with (4) 34-watt tubes per fixture. We selected Cortelco Led Lighting’s Premium T8, 18-watt LED tube to use in the office area, and our Standard T8, 18-watt LED tube for the lab area. Where we previously had a total of 880 fluorescent tubes installed we now have only 728. We were able to easily depopulate the fixtures in our common office spaces from having 4 tubes per fixture down to only 3 per fixture. In our Conference Room and in the Company President’s office we chose to install a total of (10) of our 2’ X 4’, 70-watt Flat Panels with dimming capability. Our office space is lit on average 9 and a half hours per day, and 5 days per week. Based upon this level of usage our annual Kwh before the conversion was 71,060 Kwh. After the conversion our consumption dropped to 32,785 Kwh—a 54% reduction in direct energy cost!

The next area that Cortelco LED upgraded was our 50,000 square foot warehouse. The ceiling height in the warehouse ranges from 24 feet at the outside edges up to 30 feet in the center. This area is completely filled with rows of warehouse racks that are 8 feet wide and 20 feet tall. The aisles in between racks are 8 feet wide and the floor is sealed concrete. The warehouse was lit by a total of 132 high bay fixtures. Each fixture was equipped with a lamp ballast, an open, 120 degree, metal reflector and a 400 watt metal-halide bulb. In this case we had to choose between replacing the fixture completely with a new high bay fixture or we could use Cortelco’s high bay retrofit kit. In either case we could attain a more than comparable level of lighting by installing a 150 LED replacement, and we could even not equip every other fixture. In order to minimize the amount of labor required and the amount of time to complete the project, Cortelco chose to upgrade with the retrofit kits. Although we attained an acceptable level of light by equipping alternate rows of fixtures, we decided to improve that level in the higher traffic areas of the warehouse. So we went from having (132) 400-watt metal halide bulbs down to (78) of the 150 watt retrofit kits. Applying the same duty cycle as we described above for the office space, our annual energy use for the warehouse was 125,400 Kwh before the upgrade. After installing the LED retrofit kits our consumption will drop down to 27,788 Kwh annually. This represents an annual energy usage reduction of 78%!

Finally in our manufacturing area, the ceiling height slopes up from 14 feet at the edges up to 22 feet in the center. The ceiling construction is white vinyl material supported by exposed metal beams. There are two types of lighting that was used in this area.

The general lighting was provided by a total of 25 Low bay fixtures. These fixtures consisted of a lamp ballast, and an enclosed metal reflector covered by a transparent diffuser. Each fixture was equipped with a 400-watt metal halide bulb. We determined that at this lower height and in order to take advantage of the effectiveness of the existing diffuser, the best lighting solution was to use Cortelco’s 100 watt LED Corn Lamp.

The work stations and associated office spaces were being lit by either 8 foot or 4 foot fluorescent tubes. There were a total of (46) 8 foot 110 watt tubes. Of this total, 42 were replaced by (42) 40 watt 8 foot LED tubes. The other (4) 8 foot tube fixtures were converted to tandem 4 foot fixtures which used (8) 4 foot 18 watt LED tubes. In addition there were (50) 40 watt fluorescent tubes that were replaced by (50) 18 watt LED tubes.

The manufacturing space is used 9 hours per day and 5 days per week. Our annual energy consumption for the manufacturing area was 38,385 Kwh which was reduced by 70% down to 11,790 Kwh. In summary our electrical demand was reduced by a total of 162,482Kwh annually or a savings of $16,250 per year!