Batteries have been undergoing a bit of a renaissance lately, but a new experiment hopes to lay the groundwork for someday eliminating them altogether. The University of Washington–Seattle’s Sensor Systems Laboratory has created and tested a camera powered solely by Wi-Fi signals.
The system, known as power-over-Wi-Fi, uses energy contained in ambient Wi-Fi signals to send power to the camera. The team discovered that energy from the signals produced nearly enough power meet the needs of most low-power devices.
Wi-Fi signals are broadcast through inconsistent bursts across different frequencies, making it difficult to continuously harness their power. Project lead and PhD student Vamsi Talla and his research team modified Wi-Fi routers to produce digital noise on channels that weren’t sending data, creating a constant low-power source.
By tweaking the routers, Talla’s team generated a strong enough signal to power a surveillance camera and keep temperature sensor running. Both devices were several meters away from the power source.
By adding a rechargeable battery, the researchers were able to increase the range to nine meters (about 30 feet).
Though the experiment did lead to slower data speeds from the wireless connection, it represents a potential breakthrough for the world of Internet-connected household gadgets known as the Internet of Things. Instead of needing to find an outlet for every connected object in your home, you might someday be able to power them with the Wi-Fi signal they’re already using to talk to the world.