Disconnecting the electrical umbilical cord. Image by Jay Myrdal/Getty.
In a world powered by mobile technologies, power transmission remains a significant hurdle. From unsightly power lines to the mess of cables behind my desk, power transmission is inherently aesthetically as well as functionally challenged—not to mention consumes a massive amount of material resources.
The idea of wireless power transmission has been around for some time, and inventor Nikola Tesla advocated the transmission of power wirelessly at great distances. However, technological difficulties and safety concerns have thwarted the development of this technology—until recently.
Pittsburgh-based Powercast has developed a method of transmitting power via radio waves, and has demonstrated the capability to recharge small devices like remote controls and alarm clocks. The company Powerbeam advocates the use of infrared lasers focused on photoelectric cells, a technology that lacks efficiency but might eventually power wireless speakers and laptops.
Another technique is called magnetic induction—a process in which a fluctuating magnetic field generates electric current in a nearby coil—but which only works up to a few millimeters of distance. MIT’s Aristeidis Karalis is currently expanding the reach of this technology to two or more meters—enough distance to power many home appliances and mobile devices conveniently.
Safety concerns remain, of course, but early tests suggest that magnetic induction would not surpass the minimal thresholds set by the International Commission on Non-Ionizing Radiation Protection. At the rate of current progress, we may soon find our mobile technologies completely untethered from the outlet.