What it means. Solid-state lighting, or SSL, could be the next big thing in residential lighting. SSL refers to a type of bulb—or lamp, in industry parlance—that uses the movement of electrons through a semiconductor material to generate light. The semiconductor is in a solid block form, hence “solid state.”
Because there’s no filament that heats up (and eventually burns out), SSL is up to 50 times more efficient than incandescent bulbs, claim manufacturers. SSL is also said to last as much as 10 times longer than compact fluorescent lighting and contains none of the potentially harmful mercury that has brought CFLs image down to earth and made recycling them a hassle.
Why the buzz? SSL has existed for decades under the name LED, short for light-emitting diode (the semiconductor material involved is a diode). But LEDs are not the only kinds of SSL. For example, laser technology is a form of SSL, and organic light-emitting diodes, or OLEDs, are on the horizon. As a result, the lighting industry is transitioning toward the more all-inclusive solid-state lighting moniker. “Within the broad category of TVs, you have several options, including LCD, plasma, and OLED. Similarly, solid-state lighting refers to anything that is not a conventional gas-based lighting technology,” says Govi Rao, chief executive officer of Lighting Science Group (LSG), a manufacturer of lighting equipment.
The switch to SSL might also have to do with the marketing of LEDs, which are still leading the way in this technology. For years, LEDs were limited to commercial use, for example in traffic signals and airport signage. The fact that they couldn’t generate pure white light kept them out of the residential market, except as the red indicator lights on electronic devices. But manufacturers are getting closer to a perfect white LED; LSG, for one, just launched a line of replacement LEDs (shown). Unfortunately, no matter how good the technology gets, some consumers will always associate LEDs with Lite-Brite. By giving the lights a different name, manufacturers can in a way reintroduce them to consumers.
Whatever its name, SSL is still years away from wide residential use. But it’s making steady inroads, including for undercabinet lighting. We’re currently testing these task-lighting fixtures for our August 2008 special kitchen section. Five years ago, we wouldn’t have covered SSL, but this year, it’s a theme in the story. Without giving too much away, we’ll just say that the purported efficiency of SSL is pretty solid.—Daniel DiClerico