Ultrasonic Dishwasher from Bosch

There is often debate about which is greener, washing dishes by hand or with a dishwasher? The discussion will probably end when Bosch's new ultrasonic dishwasher goes on sale. The Patent application claims "A dishwasher machine (1), in particular a domestic dishwasher machine, is described, comprising a washing container (2) and devices for washing items to be washed by means of washing solution, as well as a sound wave generator (5), wherein the sound wave generator (5) is used to generate a sound wave which at least assists the drying process of the items to be washed. In order to achieve the highest possible efficiency of the drying process, the sound wave generator (5) is designed to deliver sound waves of different frequency and/or amplitude."

The New Scientist notes that : "The conventional method is to heat the dishes while they are being washed. The dishes retain thermal energy, which heats any leftover water so that it evaporates quickly once the wash is over.

osch says that zapping the dishes with ultrasound instead could be a far more energy efficient way of drying them off.

The sound waves make surface water vibrate, causing it to break up into droplets. The waves also reduce the cohesion of the droplets so they roll off dishes more quickly. Sound alone is unlikely to dry your dishes completely but Bosch hopes that combining the technique with minimal heating or fan drying will make dishwashers far more energy efficient." ::New Scientist note: US patent database does not like firefox.