A recent study funded by the European Commission shows a worrying trend in a business-as-usual scenario for greenhouse gas emissions. The weather related premature mortality can increase 50 times by the year 2100: mainly due to heat waves, especially in the south of Europe (Increasing risk over time of weather-related hazards to the European population: a data-driven prognostic study. Forzieri et al, Lancet Planet Health; vol. 1 august 2017, 200-208).

Proof of concept

Rome has about 2800 fontanelle; drinking fountains nicknamed nasone (big nose). They run continuously but only a fraction of the water is used for drinking. Every day 2 to 3 cubic meters of nice 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. This also provides a resting place / meeting point. The heat exchange can be made in any shape e.g. like leafs on a tree so they will also provide shade.

An existing fontanelle can be used unchanged to test this idea: connecting it with a simple hose over the nasone. As a proof of concept, and finally after fine tuning one or several different designs it can be used throughout the city. The heat exchange will only be turned on in summer.

When the temperature increase of the water is to much for drinking, the option of drinking nice cold water is the same: closing the nose stops the water and a fountain just before the heat exchange will expel the cold water.

One more trick up the nasone's sleeve

The lakes where water is coming from have a thermocline in summer: at a certain depth (15+ meter) the water temperature suddenly drops. Water of 4 degrees is the most dense and so water of higher temperatures will 'float' on that cold water. If in the heat of summer the water is taken from below this thermocline than the water temperature will be even 5 - 10 degrees colder from the start. Combining the much needed repairs to the piping - an estimated one third or more of the water is lost - with attention to the heat loss during transport will have a positive effect on the amount of cooling that is possible in the city itself.

The kickof for more idea's

Next, the challenge is to design more every day applications that can be used all around the world. Flushing the toilet with cold water is also a waste of cooling potential: first the water can go through a radiator like heat exchange. The same is true for the shower, washing machine etc. You will also need to heat up the water less: so you will save energy as well. The city uses 1.4 milion cubic meter of water every year where an important part of the cooling potential is not used yet.

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Engineering Solutions
        for Rome
Voorstraat 48
4797 BH  Willemstad NB
The Netherlands

Tel.: +31(0)6 - 222.856.99

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