Canadian engineer Louis Michaud proposed the Atmospheric Vortex Engine (AVE) around 2005: a squat cylindrical tower — 100 m across, 200 m tall — that spins up a controlled tornado inside itself and harvests the pressure drop with turbines at the base. The tornado never leaves the tower because we stop feeding it warm air. It's a heat engine whose working fluid is the atmosphere and whose smokestack is made of centripetal acceleration.

The physics is uncontroversial. A natural tornado is a Carnot-ish engine running between warm humid boundary-layer air (~300 K) and the cold tropopause (~220 K). Ideal efficiency:

η = 1 − T_cold/T_hot = 1 − 220/300 ≈ 27%

You don't need a real 10-km-tall chimney to reach cold air, because the vortex itself connects the hot base to the cold upper atmosphere through its own low-pressure core. That's Michaud's key insight: once the swirl is established, the atmosphere becomes the tower.

Back-of-envelope: a 200-MW AVE bolted to a coal plant

Feed the tower with warm humid exhaust from a 500-MW-electric power plant's cooling water (typical waste heat ~1 GW thermal, condenser water at 40 °C).

• Air enters tangentially through 12 louvered vanes at the base, at ~15 m/s.
• Inlet mass flow: ṁ = ρ·A·v ≈ 1.15 × (π·50² × 5 m gap) × 15 ≈ 680,000 kg/s
• Specific enthalpy gain from warm+humid vs ambient: ~40 kJ/kg (mostly latent).
• Heat throughput: Q̇ = 680,000 × 40,000 ≈ 27 GW thermal

That's a suspiciously large number — because a vortex, unlike a smokestack, entrains vastly more ambient air than the heated inlet. Michaud's own modeling suggests only ~10–20% of the tower's throughput needs to be the deliberately-heated stream. Applying the Carnot ceiling with real-world losses (turbine ~70%, vortex stability ~50% of ideal):

P_electric ≈ 0.10 × 27 GW × 0.27 × 0.70 × 0.50 ≈ 250 MW

Roughly doubling the plant's output using heat that was already being dumped into a river. LCOE estimates from Michaud's group land near $0.03/kWh — competitive with anything.

Where physics starts pushing back

Pressure drop at the base. Real tornadoes see core pressure deficits of 10 kPa. A 100-m-diameter tower with that deficit pulling air through base turbines: P = ΔP·V̇ = 10,000 Pa × 100,000 m³/s = 1 GW of shaft power — the number checks out.

Structural loads. A 10 kPa deficit on a 100 m × 200 m cylinder = 200 MN of inward pressure. The tower wants to implode like a beer can. Solution: cheap, redundant, low tower with buttressed steel ribs — the walls don't hold weight, only radial pressure.

The scary failure mode. If the vortex "leaks" out the top and stays coherent while feeding on ambient boundary-layer humidity, you have accidentally built a tornado generator. Michaud's fix: kill the heat supply and the vortex disintegrates within minutes. Testing (a 4-m prototype at Lambton College) confirmed rapid decay, but a full-scale unit near a city needs an emergency reservoir of dry ambient air and vane-slamming interlocks — think SCRAM, but for weather.

Meteorological externality. A grid of 100 AVEs each processing 1 GW-thermal moves 1% of the regional latent heat budget. Local convection patterns shift. Downwind rainfall may drop measurably. You are, at industrial scale, doing weather modification as a side effect of electricity generation.