Case Histories: Office Lighting
Pennsylvania Power & Light Saves Almost $250,000 Annually Because Of Better Lighting
Drafters located in Pennsylvania Power & Lighting Company’s (PP & L’s) N3 Drafting Room in Allentown, Pennsylvania were experiencing frustration. They were unable to work up to their potential, and were making too many errors, because of inadequate illumination.
Light from the overheard fixtures was bouncing off the surface of the task and into their eyes, creating a form of indirect glare known as a veiling reflection. PP & L management determined that a change was in order, and that the new lighting selected could also be more energy-efficient than that which comprised the existing system.
Before implementing the comprehensive change-over called for, it was decided to convert only a portion of the overall space to assess impact. Results were impressive. Overall operating and maintenance (O&M) cost experienced before conversion amounted to $12,475 annually.
After the modernization, it was projected, these costs would be trimmed by 76 percent, to just over $3,000 per year. As significant as the O&M cost reduction was, it took on the appearance of being minor by virtue of productivity improvements. Actual measurement showed that the new lighting, which virtually eliminated veiling reflections, permitted workers to perform their tasks more than 13 percent faster.
For purposes of projections, however, management decided to rely on a 7.5 percent “number.” Even at that rate, however, the productivity benefit was projected to be worth $235,290 per year. It was known that a number of errors were avoided as a result of the new lighting, but the value of these could not be quantified.
Even a relatively minor error could have major dollar implications, especially when it is not discovered until construction, or even later. It was noted, too, that absenteeism seemed to decline after the new lighting was installed, a result, some said, of less eyestrain and fewer headaches.
All told, the bottom line benefits of better lighting were projected to save PP & L $255,929 per year. The cost of the new lighting was projected at $48,882, for a simple payback of 73 days.