To better understand the obstacles to manufacturing, specifying, procuring, and installing
LED lighting products, the U.S. Department of Energy's GATEWAY program has released
a report evaluating the long-term performance characteristics (chromaticity change, maintained illuminance, and operations and maintenance) of
LED lighting systems in four field installations, each of which was previously documented in its own DOE report:
The four evaluations illustrate that SSL use is often motivated by advantages other than energy savings -- including maintenance savings, easier integration with control systems, and improved lighting quality.
They demonstrate that the success of any lighting implementation can't be determined only by a simple review of technical performance data, but instead depends on full consideration of the individual project goals and priorities.
For a closer look at the findings, download the full report. 
