SSL Technology Update: November 5, 2012

Nov. 7, 2012
Tunable light is a hot topic this week, with Philips announcing Hue retrofit lamps and the Lighting Research Center releasing data indicating that exposure to blue light can stimulate us and boost productivity. We also have some good research data on LED street lights.

The solid-state lighting story making headlines in the past week came courtesy of Philips lighting. The company has released its consumer-targeted LED retrofit lamp called Hue. Hue can output 16 million colors and white light that's tunable in color correlated temperature. The new lamp is controlled with an Apple or Android app and the tablet or smartphone links to the lamp over a data network bridge to the ZigBee wireless network embedded in the lamp.

There are certainly convenience-oriented applications for the lamp, such as the ability to remotely turn lights on before you arrive home. But Philips believes the tunable color has benefits for our wellbeing and productivity as well. The design was enabled by a lime-green LED with breakthrough efficiency that is combined in the lamp with red-orange and royal-blue LEDs. A starter kit with three lamps and the ZigBee bridge is available at Apple stores for $199 dollars.

Speaking of the impact of tunable light on our wellbeing, the Lighting Research Center has new data on the topic. New research indicates that morning exposure to blue-tinted white light, with spectral energy focused in the short wavelengths, can help students cope with lack of sleep and focus better. The blue light raises the level of the hormone cortisol produced by the adrenal gland and can stimulate the body. The issue remains as to how we should get that exposure, although a product such as Philips Hue is a possibility. Ironically, tablets and notebook PCs provide blue light as well.

Moving to outdoor lighting, there is a report from the Northeast Group on LED street light installations with interesting data points. After surveying more than 100 municipalities that have installed LED street lights, the firm says 95% are satisfied with the result. The average annual savings in energy and maintenance cost is 60%. The firm says that energy use could be cut another 20-30% with adaptive controls. But the most important point was on technology penetration. Despite all we hear about LED street light installation, less than 1% of the lights in the US have been converted to LEDs at this point. There is plenty of opportunity left in the application for players up and down the LED lighting supply chain.