Lighting evolves based on need. Incandescent made way for brighter fluorescent. Fluorescent made room for solid-state lighting (SSL). The next big idea may be light-emitting diodes (LEDs). While they are an SSL source, LEDs are new to general lighting applications.
daylight harvesting control systems have become a common feature in green buildings, and with ASHRAE/IES 90.1 2010 now the baseline energy design standard, it also is expected to become a staple in mainstream construction.