A new spin on clean energy: tornado power

I have a feature in today’s Toronto Star about a retired engineer from Sarnia, Ontario, who has spent the past four decades of his life studying the possibility of creating man-made tornadoes from industrial waste heat so that their energy can be harnessed for clean electricity generation. More recently, Louis Michaud has formed a company called AVEtec Energy, filed and obtained patents, and has partnered up with the University of Western Ontario’s wind-tunnel lab to study small prototypes and do computer simulations of his “vortex engine” process. He’s also managed to raise some early research funding from the Ontario Centres of Excellence and now faces his biggest challenge yet: convincing private investors to fund a large-scale working pilot plant.

It may sound like a whacky, out-there idea, but the experts I spoke with for the feature don’t doubt the technical possibility of creating a man-made tornado. After all, the principles of convection are pretty straightforward. Heat rises when you’ve got a certain temperature differential, and as it rises it swirls — kind of the reverse of what you see when water goes down a drain. AVEtec’s pitch might raise eyebrows, but many are taking it seriously. For example, its advisory board consists of climate experts from Oxford, Cambridge and MIT, including MIT professor and well-respected hurricane expert Kerry Emanuel.

Michaud envisions building a large cylindrical building 200 metres in diameter and about 50 meters high, and this structure would have an open top. Heated waste water from a power plant that would normally go to a cooling tower would instead be diverted to the vortex building and into 10 or more strategically located cooling cells, where fans would blow so the air could pick up the heat energy from the water. The hot air from the 10+ intake ducts are then pushed at an angle into the cylindrical building, where you see the beginnings of a whirlwind. As the hot air rises it gathers energy and creates a vortex that reaches higher and higher into the atmosphere. At a certain point the fans pushing the hot air into the vortex are turned off. The vortex, now hungry for more heated air, begins to suck in the air on its own. Suddenly, what were fans now become turbines that spin as the air is drawn in. The turbines are connected to generators that produce clean electricity as long as a constant source of waste heat is provided to feed the vortex, which at this point is a full-fledged tornado stretching into the troposphere.

Michaud calculates it would cost $60 million to build such a plant. But because it would be replacing the function of a cooling tower, that figure would be offset by up to $20 million. The end result, assuming it works and is safe, would be a 200 megawatt power station producing clean energy at less than half the cost of a coal plant.

Now, the obvious questions — Noise? Safety? Control? Birds? Airplanes? Fear? Michaud admits these are challenges, not technical ones, but public opinion challenges. Changes of perception can only come through education, he argues, meaning the best approach would be to build one pilot plant so people could see it working. He said noise wouldn’t be a huge issue because most of the noise in tornadoes comes from the debris they pick up, and the vortex engine wouldn’t suck in debris. He says birds know better, and no-fly zones could keep airplanes away. As for safety and control, the vortex would be kept stationary in the cylindrical structure so wouldn’t be able to move around — theoretically. Dampers on the air-intake ducts could control the air flow into the vortex building, acting like a throttle that can keep the vortex from twisting out of control.

Some aren’t so convinced, as you’ll read in the feature. But what strikes me is how such an idea is at least being considered, compared to five or 10 years ago when Michaud would be written off. Having covered this cleantech sector for three years now, I’ve noticed that with increased concern over global warming people are becoming more open-minded about thinking outside the box.

Speaking of outside the box, Michaud says his vortex engines could help us directly manage climate change. He says there’s no reason hundreds of his vortex engines couldn’t be stationed in the ocean along the equator, where ocean water is warm enough to provide energy for creating a tornado. Why do this? Well, the greenhouse effect prevents heat that hits the earth’s surface from radiating back into space, so Michaud argues that his vortex network would act like air conditioners that suck the hot air high into the atmosphere where the heat can more easily escape. All I can say is…. Wow!

This concept is similar in many ways to the solar tower idea being pursued in Australia. The idea there is that solar energy is collected passively on the ground in a kind of large sprawling greenhouse structure. The air within this greenhouse heats up and flows toward a large chimney in the centre. The air gathers speed as it rises through the chimney and a large turbine inside spins to generate electricity. The problem with this is that to get, say, the 200 megawatts that Michaud wants to produce from his vortex engine, you’d have to build a huge chimney that stretches a kilometre into the sky. The greenhouse on the surface would also need to be large. Both taking up a lot of space and very costly — the economics don’t work well. Michaud believes his vortex engine overcomes this problem because the vortex forms its own chimney of air, meaning one doesn’t have to be constructed. Also, by creating a tornado you generate much more power that can be converted into electricity.

So, crazy or ingenious? What do you think?