Leviton WSC15-IRW Wireless Self-Powered PIR Occupancy Sensor, 1500 Square Feet, White Zero Power Consumption: Solar power provides the energy to keep the device on and sensor technology turns the lights off, eliminating additional expenses to the end user&#8217;s energy bill Zero External Power Required: With no power wire limitations, this enables the installer to place the sensor in the optimal location of any application to capture minor motion and reduce false OFFs Self-Powered, Self-Charging: Angled solar cells are optimal for light collection enabling the sensor to capture additional ambient light over flat solar cells &#8211; 100 LUX vs. 70-80 LUX Quick Charge Time to Operation: Self-powered technology enables the sensor to be operational after a minimum charge time of 1 minute True Wireless: Sensors are self-powered and communicates with all LevNet RF and EnOcean Receivers via radio frequency