Transmitting power over-the-air may seem like science fiction, but Powercast is already delivering power to IoT and select consumer devices over the unlicensed 915MHz band in the US.

Powercast is selling its long-range, power-over-distance technology as suitable for uses in everything from batteryless price tags to electronic paper displays (EPD) and even wireless charging grips for Nintendo's Joy-Con game controllers.

The company has developed this new technology using broadcast RF energy (radio waves) converted into DC power. In the US, transmitters use the 915MHz ISM band to send RF energy over the air to Powercast's tiny Powerharvester receiver chips embedded in products.

This means that devices within the 80-foot range of the transmitters can charge automatically without needing a line of sight to transmitters. For Internet of Things (IoT) applications, the system can recharge small batteries such as watch cells or AAs for multiple years, thereby prolonging their usable field life.

Powercast has recently received three new certifications from the Federal Communications Commission (FCC), adding retail applications to the company's existing FCC approvals for deployments in consumer, commercial and industrial environments. These include applications in robotics and manufacturing machinery.

Powercast has two transmitters for different applications. Its 80-foot-range transmitter was FCC-approved in 2010 for commercial and industrial applications.

The company also has a smaller PowerSpot transmitter for consumer applications. The PowerSpot can be a standalone charger, or be built into other consumer products that allows them to charge multiple compatible devices.

For the future, Powercast COO and CTO Charles Greene expects the technology may be used with 5G devices. He envisages a "5G hotspot" in the consumer's home that can be used to remotely charge devices.

Pittsburgh, PA-based Powercast is a private company that first started in 2003. "We've been a profitable company for about six years," says Greene.

Startups working in this area include startups like Wi-Charge and uBeam.

— Dan Jones, Mobile Editor, Light Reading