Scientists at Rensselaer Polytechnic Institute’s Lighting Research Center (LRC) have developed a simple, cost-effective, energy-saving device designed to harvest daylight automatically. The DaySwitch™ was designed as an alternative to traditional dimming ballast systems that adjust light levels by reducing the lamp current.
How the DaySwitch™ works
The DaySwitch™ eliminates wasted or unwanted electric light by sensing when sufficient daylight is available to take the place of electric light, and then responds by turning off the fixture. When daylight decreases, the device turns the light back on.
A built-in microcontroller automatically calibrates the DaySwitch™, allowing for self-commissioning and easy installation and maintenance. The design also includes a light-to-frequency photodiode that, together with the microcontroller, provides accuracy over a wide range of light levels (1 to 12,000 lux).
According to the LRC research team, commercial customers can expect a two- to five-year payback in retrofit applications and a one- to three-year payback when the DaySwitch™ is built into fixtures installed in new construction.
For a brochure on the design, download this pdf file.