High Quality Content by WIKIPEDIA articles! The solar updraft tower is a proposed type of renewable-energy power plant. It combines three old and proven technologies: the chimney effect, the greenhouse effect, and the wind turbine. Air is heated by sunshine and contained in a very large greenhouse-like structure around the base of a tall chimney, and the resulting convection causes air to rise up the updraft tower. This airflow drives turbines, which produce electricity. A successful research prototype operated in Spain in the 1980s, and many modelling studies have been published as to optimization, scale, and economic feasibility.