Autopia Ampere

This is crazy.

Autopia Ampere will begin as a series of wire-mesh armatures anchored atop a sea mountain. Once in place, they will be connected to a supply of low-voltage direct current produced by solar panels. Over time, electrochemical reactions will draw minerals from the sea to the armatures, creating walls of calcium carbonate, which is what us landlubbers commonly call limestone.
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A huge limestone dam will surround the city, Hilbertz says, and building components will be grown in the sea, as shown in the illustration (right). Solar and wind generators will furnish power. So too will a thermal energy conversion system that will extract power from temperature differences among different ocean currents.
One of the cornerstones of the new city’s economy would be “limestone farming.” The mineral accretion technique that has built reefs in the Caribbean and that could one day build marine cities could also make building components for use on land. Using appropriately shaped wire forms, the minerals deposited from seawater could grow building blocks, wall panels or complete building components just like those that would build a sea-born city, but for use on dry land.

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