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Electrical Troubleshooting Quiz, August 28, 2012

After a lighting upgrade to your facility, a recent review of the energy bills doesn't show any of the expected savings

A few months ago, your facility underwent a lighting upgrade. Upper management wanted to reduce energy costs while holding upgrade costs down. Their solution was to replace all of the existing fluorescent lamps with energy-efficient ones and to replace incandescent lamps with CFLs wherever practical.

However, a recent review of the energy bills doesn't show any of the expected savings. In fact, total kW consumption rose about 15% despite no significant change in usage patterns. Making matters worse, people are complaining about the lighting quality. The lights seem to flicker, and there's a high rate of burnout that often leaves areas under-lit.

Now what?

First off, let's make a comment about this "lighting upgrade." This wasn't an upgrade; it was merely a light-bulb change. While it's often advantageous to simply replace fluorescent lamps with more efficient ones, new lamps must match existing ballasts. The many lamp failures strongly indicate a lamp-ballast mismatch.

The "new-light-bulb-only" approach typically leaves most of the potential energy savings unrealized while also failing to optimize the lighting. Think of lighting as a system that starts with the transformer that supplies the lighting branch circuit panel and ends with the lens or shade. Evaluate everything in between.

The CFLs are problematic for several reasons, including a hugely adverse effect on power factor. Put the incandescent lamps back in, or replace the system with a different lighting technology. A different technology could be impressive, especially the LED in the wall sort for areas like lobbies and break rooms.

Upgrading the whole lighting system is nearly always the way to go.

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