Smog tower. Computer graphic of a proposed tower design to remove smog from air whilst making power. The tower is made from steel columns (red) with teflon-coated fibreglass (white) stretched between them. It is up to 60 storeys high & 150 m wide. A mist of charged water droplets is sprayed into the top of the tower. These droplets attract & absorb smoke particles. Some of the droplets evaporate, cooling the air and making it sink into the tower. As the air exits at the bottom of the tower it passes through wind turbines; these generate more electricity than is needed to pump the water up the tower. Invented by Melvin Prueitt in the USA.