Benefits to Lighting Upgrades, Even in Relatively Recent System
August 25, 2015
While upgrades in the 1990s and 2000s cut lighting power densities from 2.5 to 4 watts per square foot (W/SF) down to 1.5 to 1.8 W/SF, some of today's options may cut that to .7 W/SF, or even lower. Where electric rates and financial incentives are high, even reduction of only 10 watts per fixture may be cost-effective.
Many upgrades may be pursued as part of routine maintenance. For example, in some facilities early model T8 ballasts installed over 10 years ago may be starting to fail. Instead of replacing in kind, the time might be right to switch to a more efficient technology, such as LEDs.
Once a fixture must be accessed and opened for maintenance, the labor to do so becomes a sunk cost. The value of that investment is maximized by instead deploying whatever cost-effective options are available. Payback calculations then include only the costs of new equipment and any additional incremental labor.
Such work may involve replacing both lamps and ballasts with an LED retrofit kit that includes a "driver" (works like a ballast) and a device (shaped like a flat strip or fluorescent tube) containing many LEDs. Not only has re-lamping then been essentially eliminated for a long time, but the energy cost of lighting may be cut by 20 percent or more.
Some early upgrades maintained the parabolic louvers found in fixtures from the 1980s and 1990s. A variety of new kits and lenses are now available that provide a more modern look while eliminating the "cave effect" (darkened ceilings and upper walls) those louvers created.
Not yet ready to make the leap to LEDs? Just change lamp and ballast specs so the facility buys only super T8s that provide about the same lumens, using fewer watts, while lasting almost as long as LEDs. While more expensive than standard T8s, the ROI, when accounting for both reduced energy and maintenance costs, may be acceptable.
To learn more about the possibilities available with lamp retrofits, read this