Wireless Power Overview
Since the late 1800s, scientists have dreamed of achieving wireless power transmission – the delivery of power to a distant location without wires. Laser power beaming uses a laser to send concentrated light through the air or fiber optic cable to a remote receiver that converts the light to electricity. It works much like solar power, where sunlight shines on solar cells that generate electricity, but instead it uses high intensity laser light aimed at specialized photovoltaic (PV) cells that convert the laser light into electricity. Key differences from solar power are that the laser is much more intense than the sun, it can be aimed anyplace in line-of-sight of the transmitter (including with the aid of a telescope or mirrors), and it can operate 24 hours/day. Consequently, laser power beaming has numerous advantages over solar power.
The wireless power system starts with a laser running on power supplied from a standard industrial electrical outlet or a generator. The laser light is shaped by a set of optics to define the beam size at its destination. This light then propagates through air, the vacuum of space, or through fiber optic cable until it reaches the PV receiver. This array of PV cells then converts the light back into electricity.
Electricity is traditionally transmitted using wires (usually made of copper). Among their less desirable traits are that electrical power lines are expensive to install ($20,000 or more per mile for low power residential lines, and $250,000 or more per mile for high-voltage transmission lines), can require significant time before an installation is completed, could fail at any point along their entire length, and cannot be moved to a different location once installed. Perhaps most importantly, though, there are many places where electrical power lines are impractical (e.g., to an aerial vehicle), uneconomical (e.g., to distant, remote locations), or simply impossible to install (Earth to Moon).
Wireless power delivery, on the other hand, requires physical installations at only the transmitting and receiving points, and nothing in between (an “invisible extension cord”). The receiver can be moved to a different location, closer or further away, without changing the cost of the system. Power can be available as soon as the elements are placed and turned on, instead of having to wait for wires to be buried or hung from poles.
For additional information, read our Laser Power Beaming Fact Sheet-2012