Asked by: Scott Lloyd, Leigh
Van de Graaff generators produce the highest voltages. Charge is carried by an insulating belt from a lower electrode to another at the top, accumulating across a metallic dome. They can be strapped together to form tandems for even higher voltages. A tandem at Oak Ridge National Laboratory produced the highest ever at 25.5MV (a megavolt is 1 million volts).
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