The principle of the solar updraft tower Beneath a large circular transparent roof solar radiation heats the air by approximately 30 °C. This hot air enters a vertical tower tube at the center of the roof creating an updraught with a velocity of about 60 km/h which propels turbines equipped with electrical generators. If required, continuous 24 hours-operation can be achived by waterfilled plastic-tubes under the roof.			The water heats up during the daytime and releases its heat at night. A true base load power plant! With tower tubes up to 1000 m high and roofs several kilometers in diameter each power plant can achieve an electrical output of 100 - 200 MW. QuickTime Movie 1 Mb