AEDC lighting improvements also save energy

  • Published
  • By Shawn Jacobs
  • AEDC/PA
ARNOLD AIR FORCE BASE, Tenn. --  Arnold Engineering Development Center (AEDC) is continuing to implement an Air Force directive to "make energy a consideration in all that we do."

One of the most visible energy-saving upgrades is to interior lighting for buildings on base. For example, the new lighting system in the Engine Test Facility B (ETF-B) is estimated to save more than $30,000 a year in energy. The savings from this lighting upgrade came from the use of longer-life lamps and motion sensors. Similar interior lighting improvements in the Aerodynamic and Propulsion Test Unit's (APTU) high bay are expected to save more than $11,000 a year. The APTU lighting includes lighting control panels instead of motion sensors.

"The savings include maintenance savings also," said John McInturff, energy program manager for Aerospace Testing Alliance (ATA), AEDC's operating contractor. "Additionally, we should note that the majority of the savings come from the control system turning the lights off when not needed."

John Payne, ATA electrical design engineer and base interior lighting systems manager, performed an economic analysis regarding what fixtures to use in both facilities. He said they chose induction type fixtures because from a maintenance standpoint they outperform other lamps that were considered.

Induction lighting is basically a fluorescent-based technology that operates without the use of an electrode, according to Payne. Energy is transferred to the lamp by an inductively coupled high frequency magnetic field, which reacts with phosphors to create illumination. The absence of an electrode eliminates the common failure point found in most lamps, therefore providing an extremely long-lasting light source.

Payne evaluated two other types of lighting, high intensity discharge (HID) lamps and T5 high output (T5 HO) fluorescents, but chose induction because of maintenance factors.

"The life of the induction was five times longer than either one of the other two [types of lighting considered]," he said. "It's 100,000 hours compared to 20,000 hours per lamp."

Payne said there was actually a lack of sufficient lighting to begin with in both facilities.

"In both those facilities, I would say there was 10-15 foot candles on the average ... because they work with those small items [it's recommended] the range of the foot candles - which is the amount of light - to be anywhere from 50-100 foot candles maintained," Payne said. "Maintained is after the maintenance factor, which is usually about 75-80 percent. Most of them we tried to design it up to 75 foot candles.

"So you can imagine if we're designing 75 foot candles and the foot candles before was only 10-15, so you can see where they didn't have much light. And on top of that ... the Air Force is driving to reduce the amount of energy per facility something like 30 percent, but that's 30 percent total energy and that counts everything. The lighting alone sometimes will take that 30 percent."

Payne said the improved lighting has also increased safety in the AEDC workplace.

"They're very happy with what they've got now versus what they had before," Mark Gifford, the ATA project manager for the ETF-B lighting improvements said. "They didn't have anything before and there were even points where it actually stopped tests due to the fact that they didn't have the lights and they had to go get some backups to do any kind of work over there whatsoever.

"With those motion sensors, that really works out nice because of the areas that they've got in the basement. [Before] they'd turn the breakers on and they'd light that whole building up in the basement and they'd just be in one part of it."

The induction lighting in ETF-B is confined to the high bay. Fluorescent lights in the basement were upgraded and the motion sensors were added to keep them from remaining on 24 hours a day. The project was completed approximately two years ago.
Darrell Townsend was the ATA project manager for the APTU lighting upgrade, which was completed in early 2010. He said employees in that facility are happy with the results.

"They've not only got more lighting, they've got new capabilities now," he said. "They've put in the smart breakers, so I guess at some point in time they can be controlled remotely. Right now, there's a controller inside the lighting panel and they can program it to come on at a certain time and go off at a certain time.

"At APTU, the building manager and craft people gave us a lot of support, and of course that makes the cost of the project go down ... if you get a lot of cooperation. [On] any one of these lighting projects, having the support out your building occupants is going to be instrumental."

Payne said similar projects are being implemented across the base, as funding allows.

"We're putting the lighting control panels in the ETF and PWT (Propulsion Wind Tunnel) office buildings," he said. "On Warehouse 1, we're putting the induction fixtures in there, along with the lighting control panels and occupancy sensors."

In addition, a lighting upgrade has been designed and contracted for ETF-A, lighting control panels have been installed on the second floor of building 1099 (ETF-C) and in 1088 (Space and Missile Ground Test Complex). Similar modifications are planned for the Administration and Engineering building.