Forget about the hybrid auto -- Shai Agassi says it's electric cars or bust if we want to impact emissions. His company, Better Place, has a radical plan to take entire countries oil-free by 2020.In this brief talk, Saul Griffith unveils the invention his new company Makani Power has been working on: giant kite turbines that create surprising amounts of clean, renewable energy.We all know the words around electricity -- “charge,” “positive,” “battery” and more. But where do they come from and what do they really mean? Let the history of these words illuminate the physics of electric phenomena.

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