Bladeless Wind Turbine

Someone asked me to comment on the Vortex, or bladeless wind turbine.  I believe I’ve written something on this earlier, but I’m having trouble finding it.  Here goes:

The energy extracted from wind is proportional to the area past which the wind passes. For a smallish (2 MW) wind turbine, that’s about 60,000 square feet. Let’s say these are 60 feet tall and one foot wide, or 60 square feet. Instead of 2 MW, you’ll wind up with one one-thousandth of that, or 2 KW, barely enough to power a hair dryer.

Technically, it’s possible that you’ll do a little better than that because Betz’s Law (limit how much you can slow the wind down without blocking the way for the incoming wind) doesn’t apply.

To call this a scam is too harsh, but it’s far closer to a scam than a workable idea.