We’ve looked at tornadoes as possible energy sources before, and now Live Science has an article on the Canadian engineer with the swirling energy idea.

Tornadoes and hurricanes form when sun-heated air near the surface rises and displaces cooler air above. As outside air rushes in to replace the rising air, the whole mass begins to rotate.

Michaud got the notion of a man-made tornado — what he calls the Atmospheric Vortex Engine (AVE) — while working as an engineer on gas turbines.

“When I looked further into it, I didn’t run into anything that was impossible,” Michaud told LiveScience.

The AVE structure is a 200-meter-wide arena with 100-meter-high walls. Warm humid air enters at the sides, directed to flow in a circular fashion. As the air whirls around at speeds up to 200 mph, a vacuum forms in the center, which holds the vortex together as it extends several miles into the sky.

The concept is similar to a solar chimney with the swirling walls of the vortex replacing the brick walls of the tower. But the AVE can reach much higher into the sky where the air is colder.

With wind turbines at the inlets to the arena, Michaud calculates that as much as 200 megawatts of electricity (enough for a small city) could be extracted without draining the vortex of its power.

“Look at natural tornadoes that destroy a house or carry off a car and still have plenty of energy left over,” he said.