| Attendees at CES 2010, the consumer electronics | | | | Other than establishing the oscillating magnetic field to |
| show in Las Vegas last month, caught a glimpse of | | | | resonate with and excite the specific receiver coil -- |
| what the future might bring as Chinese appliance | | | | creating electrical energy for the appliance -- the |
| maker Haier, working with Massachusetts-based | | | | magnetic energy field produced by the powered |
| WiTricity Corporation, unveiled a remarkable 32-inch | | | | sender coil remains very close to its point of origin. |
| television -- remarkable because it had no power cord. | | | | Moreover, the WiTricity technology has a very weak |
| The Haier prototype was powered by electricity | | | | effect on biological systems -- better known as people |
| converted from an oscillating magnetic field. The | | | | and pets. |
| wireless transmission of electricity demonstrated so | | | | The MIT scientists first demonstrated their successful |
| boldly in January at an international trade show may | | | | strategy by illuminating a 60-watt bulb from 7 feet |
| fulfill a quest that began more than a century ago by | | | | away, an accomplishment first reported in Science in |
| the inventor of alternating current himself, Nicola Tesla. | | | | July 2007. The MIT News noted then that Professor |
| Wirelessly transmitted electricity was successfully | | | | Soljacic was inspired to investigate wireless electrical |
| created in 2005 by a team of physicists at MIT led by | | | | power by being awakened by warning beeps emitted |
| Professor Marin Soljacic. The company they founded, | | | | by his cell phone, which he had (once again) forgotten |
| WiTricity Corporation, is now seeking original equipment | | | | to plug in to recharge. As he looked at his wireless |
| manufacturers interested in licensing their method of | | | | phone, he realized how much more convenient it would |
| transmitting power. | | | | be if it could recharge on its own, wirelessly. |
| The WiTricity technology could loosely be described | | | | The wireless transmission of electrical energy is not a |
| as "magnetic coupling." It involves two copper coils that | | | | new idea. It was first explored by Nikola Tesla, the |
| are matched for magnetic resonance. One is | | | | brilliant scientist who developed alternating current and |
| connected to a power source (110-volt AC house | | | | the induction motor well over a century ago. Tesla |
| current, for example) and is the "sender." The sender | | | | proved the victor over Edison, who was a proponent |
| coil converts the electrical current to a non-radiating | | | | of direct current for the generation of electrical power, |
| magnetic field that oscillates at a specific frequency | | | | in the so-called "current war." Finding a way to make |
| and permeates the room. In order for the converted | | | | the wireless transmission of electricity work over a |
| energy to be utilized, this oscillation frequency of the | | | | distance greater than the diameter of the coils was at |
| magnetic field must excite the matched coil housed | | | | the heart of the problem, as was avoiding directed, |
| within an electrical device, such as the TV on display | | | | intense and potentially harmful electromagnetic |
| at January's CES. | | | | radiation. The scientists at MIT prevailed over these |
| The idea of matched resonance of the coils would be | | | | age-old problems. |
| akin to 100 wine glasses on a table, each with a slightly | | | | The exhibition of the Haier television with WiTricity at |
| different amount of water so that each would vibrate | | | | the Las Vegas CES simply demonstrated the |
| at a unique frequency. An opera star who would | | | | feasibility (or "proof of concept") for the wireless |
| sustain one note for a sufficient interval of time could | | | | transmission of electricity. Nevertheless, Haier was |
| eventually cause the one particular glass matching the | | | | honored with the Popular Science "Product of the |
| frequency or pitch to resonate enough to shatter. In | | | | Future" award for their efforts so far. The company |
| other words, the oscillation of the magnetic field would | | | | remains committed to planning for the commercial |
| affect only the appliance equipped with the matching | | | | production of efficient, wirelessly-powered appliances |
| coil. | | | | and devices as soon as possible. |