UCHIMIZU

The heat-island phenomenon has become a problem in big cities like Tokyo that are saturated with buildings and paved roads. It is one of the major causes of urban-type torrential rain and global warming. There is a traditional custom in Japan called Uchimizu that has been practised since the Edo Period. Water is sprinkled over streets and yards using wooden buckets and ladles. The heat transforms the liquid water into water vapour, thus cooling the temperature of surfaces and air. UCHIMIZU pumps water from the bottom of the tank and sprinkles it radially from a side nozzle of the main unit, just like practising Uchimizu with one’s own hands. Simply leave the UCHIMIZU filled with water out on the veranda on a hot summer day and the water sprinkler will be activated at optimal timings. A sensor measures the ground level temperature and decides the most effective time for the sprinkling to take effect, such as mornings – when the sunlight is still gentle, and the ground level temperature is not at its maximum – and in the evenings.The device uses electricity stored with a solar charger to pump water upwards from an internal reservoir to automate the water sprinkler. UCHIMIZU also has a sensor that pauses the sprinkling function when someone is nearby. Furthermore, a filter removes unwanted particles so that the waste water can be recycled. Since the electricity is generated using a solar charger, it can be placed anywhere where sunlight is available. UCHIMIZU reduces electrical consumption, and with widespread usage, the heat-island effect in big cities can be ameliorated.