Forget colonies in space, one construction company says in the future humans could live in huge underwater complexes that corkscrew deep into the ocean.
Five thousand people would live and work in a modern-day Atlantis, a sphere 500 meters in diameter housing hotels, residential spaces and commercial complexes, in the blueprint by Shimizu Inc.
The vast globe would float on the surface but could submerge in bad weather, moving down a gigantic spiral structure that reaches depths of up to 4,000 meters.
The spiral would form a 15-km path to a module on the ocean floor which could serve as a resource development factory, mining rare earths and other metals.
“The company and many other organizations have spent two years designing the project, working with technologies we think will be plausible in the future,” said a Shimizu spokesman.
The project is the result of collaboration with researchers from institutions such as the University of Tokyo and the Japan Agency for Marine-Earth Science and Technology, better known as JAMSTEC.
The company’s visionaries say microorganisms called methanogens could be used to convert carbon dioxide from the air above into methane, and they envisage using the wide difference in water temperature between the surface and lower depths to generate power. Shimizu says the Ocean Spiral would cost ¥3 trillion in present-day terms, and the technology could be available by 2030.
It is the company’s third project that turns fantasy into figures.
Earlier blueprints were for a floating metropolis and a solar-power ring around the moon. In 2012, fellow construction firm Obayashi Corp., proposed putting tourists in space within 40 years by building an elevator a quarter of the way to the moon.
Obayashi said it could use carbon nanotube technology, which is more than 20 times stronger than steel, to build a lift shaft 96,000 km above the Earth.