Ingels said 10,000 is the ideal number of residents, since it would allow the island to achieve full autonomy by producing its own power, fresh water, and heat.

Ingels is best known for individual projects like the Superkilen public park in Copenhagen or a pair of twisting towers in New York City. But he told Business Insider that designing an entire city gives him room to expand his vision.

At the city scale you can achieve more, Ingels said.