Solar Wind Energy Tower Inc. (fka SWET)

[swingingRichard]

The below is a perfect example of the incorrect assumption made about the physics involved in this share-selling scam.

How It Works

According to the company website, the patented downdraft tower is a hollow cylinder that uses a “water injection system near the top and wind tunnels containing turbines near the bottom”.

The height of the proposed tower will be a staggering half-mile (2,640 feet). At this height, the atmosphere is hot and dry and heated the sun. Water is then injected near the top of the tower and weight the dry air, sinking it to the bottom of the tower. This action creates a wind force that’s strong enough to drive the turbines. (1)

When the air is heated by the sun’s solar rays along with the water, the combination creates a powerful downdraft wind. This in turn powers the turbines that turn the generators. According to Industry Tap, the single tower design is touted as producing the same amount of energy currently produced by the Hoover Dam. (2)

What's wrong with it?

Strike 1: Air gets colder as you gain altitude.

Imagine the atmosphere made up of parcels of air: the higher they are, the less strongly they’re compressed by the weight of the overlying atmosphere, and so the bigger their volume can be. Such expansion requires energy, and as the total energy in the parcel of air is fixed, it comes at the expense of thermal energy – thus lowering the temperature.

http://www.sciencefocus.com/qa/why-does-altitude-affect-air-temperature
Strike 2: The air is essentially invisible to the radiation from the sun; the sun will not heat the air very much at altitude.

Indeed, the atmosphere is transparent to shortwave radiation from the Sun, but absorbs a lot of the longwave radiation from the Earth

Air doesn't absorb light so it can't be directly heated by sunlight. Instead the sunlight passes through the air and heats the ground, and the ground heats the air.

Ergo, kiddies, the air is heated near the surface of the earth, not at 2500 feet.
http://physics.stackexchange.com/questions/40949/why-less-temperature-at-high-altitude
Strike 3: Moist air is lighter than dry air at the same temperature. But we all knew that already.