Abstract: The invention relates to the generation of electricity and the ventilation of urban areas with the use of waste heat from air-conditioning systems, waste organic matter, fuel cells and wind. A first aspect relates to the creation of a column of rising air in a stack to drive electricity-generating turbines. A second aspect relates to the use of wind energy to create a helix shape upward flow of air that may preferably augment the functioning of the first aspect. An advantage of the system is that by transferring waste heat from urban environments above habitable areas the problem of the so-called heat island effect is greatly alleviated.