Over the past two years, light-emitting diode (LED) luminaires have begun competing effectively against the fluorescent troffer as performance increases and costs decrease. With nearly 1 billion fluorescent luminaires installed in the United States, according to the Department of Energy (DOE), this is a big opportunity.?However, itís possible to keep the hardware but replace the lamps with linear LED models. In recent years, these products have come a long way in performance and cost. The primary value proposition is energy savings and longer service life. The DOE tested this and published the results in three CALiPER program reports in spring 2014.