Rome's nasoni fountains can show the way in cooling a major city to combat het Heat Island Effect.It will reduce the heat wave health risks.
Rome has 2800 fontanelle; drinking fountains nicknamed nasone. They run continuously but only a fraction of the water is used for drinking. Every day 2 to 3 cubic meters of cold water directly falls into the drains.
The specific heat capacity of water is 4186 J for every kg and every degree Celsius, for air this is 1000 J. When the water gives of 4 degrees one nasone could – in theory – cool 3237 cubic meters of air by about 10 degrees every summer day. The heat exchange will be made in the shape of a metal ‘tree bench’ around the nasone. The option of drinking nice cold water will remain: closing the ‘nose’ will open a fountain just before the heat exchange. The nasone doubles as a meeting point and example for the public.
Rome uses 1.4 milion cubic meter of water every year: the cooling potential is enormous. Next we are going to cool homes with water used for washing, shower and toilet: first the water goes through a heat exchange. You will also need to heat up the water less (energy).
The lakes where water is coming from have a thermocline in summer: at a certain depth the water temperature suddenly drops. If in summer the water is taken from below this thermocline than the water temperature will be even 5 – 10 degrees colder.