LONDON Startup EnOcean GmbH (Oberhaching, Germany) has introduced a solar-powered wireless sensor module. The STM100 unit includes three analog and four digital sensor connections, but not the sensors themselves, and integrates them with a controlling microprocessor, an RF transceiver and light energy capture and storage, in a module measuring 20-mm by 40-mm by 10-mm.
The STM100 has a two-stage solar cell. One stage provides quickly available startup energy while the other charges an onboard energy reservoir. Designed to operate indoors, the device requires only 200 lux to operate. Typical lighting values in a building range from 200 lux in hallways, through 500 lux on desktops and up to 1200 lux in display cases. The energy storage is sufficient for the module to operate continuously for up to five days in complete darkness, EnOcean claimed.
"EnOcean's patented technology lets STM100 generate a surprisingly long-range radio signal with extremely minute amounts of harvested energy," said Armin Anders, EnOcean's vice president of product marketing, in a statement. "With just 50 microwatts, a standard EnOcean transmitter will comfortably send a signal 300 meters outdoors, 30 meters indoors through walls. The secret is in the signal duration; the entire process is initiated, undertaken and completed in approximately one thousandth of a second."
The STM100 supports a wide variety of sensors including: temperature, gas, humidity, illumination, location, presence.
EnOcean's proprietary radio technology has been approved for use in Europe, the U.S. and Canada. STM100s, including solar cell, energy reservoir and radio, are available in OEM quantities for less than $25, the company said.