Wireless power explained in Science News

Last month, MIT researchers made headlines by demonstrating a system of wireless power. They were able to generate a field of energy in coil that lit a bulb a few meters away. Impressively, forty percent of the energy released by the coil actually reached the lightbulb when it was placed two meters away. The researchers called their invention "WiTricity." Trumpets sounded. Patent applications were filed. The current issue of Science News explains MIT's feat in lay terms while also putting it in historical context.

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From the article:

In the early 1900s, long before the power grid made electricity widely available, electricity pioneer Nikola Tesla devised a grand scheme to transfer large amounts of power over long distances from a tower 20 stories tall, to be built on Long Island in New York. To this day, historians puzzle over how Tesla's system was supposed to work, or whether it could have worked at all, says Bernard Carlson, a historian of science at the University of Virginia in Charlottesville who is writing a biography of the great engineer. "We can't even begin to understand what he was doing with this power stuff," Carlson says.

The project died when Tesla's financial backers pulled the plug, possibly because Tesla seemed unclear as to how to bill customers receiving wireless power. Ironically, Tesla also invented the alternating current (AC) system of power production, transmission, and distribution that would become the standard for the modern grid.

But electromagnetic radiation can indeed carry energy through air or empty space and over large distances.

Link to Science News

Previously on BB:
• MIT students demonstrate wireless power transfer Link
• Plastic electronic sheet for wireless power Link

UPDATE: BB reader Mark Friesen points out this recent Damn Interesting post about "Tesla's Tower of Power." Link