Twistower
The Twistower is an ultra light floating and rotating tower which can be applied by a solar updraft tower. In principle the tower is a stable twister bound by a rotating thin walled hollow cylinder.
A contrail is stable because droplets condense in the vortex core. The droplets move to the core outer diameter, leaving behind the latent heat in the core. This heat generates a temperature inversion at the core diameter, which due to the centrifugal force, prevents mixing of the low density core with the higher density ambient. This inversion boundary makes the vortex very stable.
A thin-walled cylinder is stronger than a temperature inversion and will generate more stable vortices. If the air in the cylinder is hot the vortex will be even more stable. If a rotating thin walled tower like the Twistower is applied for a Solar Tower it will generate a stable vortex with low flow losses.
Read more about the Twistower at GreenIdeaLive.org