Deep in the intestine of the UN headquarters, the pump sucks huge amounts of water from the east river to cool the complex with an old but energy efficient mechanism.
As more and more people want to remain cool on a planet that is constantly heated, energy experts point to this type of water -based system as a good alternative to air conditioning. But in many cases, they are difficult to create.
The system has been part of the New York complex since it was opened in the 1950s, the chief civil engineer Michael Martini told AFP during a tour of the cooling equipment.
The system, processed with the rest of the complex from 2008 to 2014, cools the UN center, using less energy than the conventional air conditioning system. The UN policy is to reduce the air temperature to about 24 degrees Celsius or 75 degrees Fahrenheit.
In the summer in New York, the river that goes to the UN headquarters – is actually a mouth of salt water – it remains much more cool than the surrounding air, which can reach 100 degrees. So the cooling of the building eats less energy.
About 26,000 liters per minute (7,000 gallons) water flow through fiber pipes to the cooling installation of the complex, which uses it and refrigerated gas to produce cold.
The system has two independent stitches to prevent water pollution that flows back into the river at a higher temperature, said the head of the cooling system David Lindsei.
Looking at the brilliant glass tower of the UN headquarters and the dome of the General Assembly, you would never understand that the Eastern River serves as a target for the UN and is more than part of the landscape.
The UN headquarters in New York is not his only building that depends on the water.
In Geneva, its Palais de Nations has a cooling system that uses water from Lake Geneva. And the UN complex in Copenhagen, which houses 10 UN agencies, depends on the cold seawater, which almost eliminates the need for electricity to cool the place.
This is a huge advantage over the approximate two billion air -conditioning units installed around the world.
“Why so rarely?” –
With the number of air conditioners to increase so as to help people who are increasingly exposed to dangerous temperatures, energy consumption for cooling has already been tripled since 1990, says the International Energy Agency that wants more efficient systems.
Examples are centralized air -conditioning networks using electricity, geothermal systems or those that use water, such as the UN complex in New York.
This latest system “is not as much as it should be about the problems we face today,” says Lili Riahi, Cool Coalition Coordinator, grouping of countries, cities and companies under the auspices of the United Nations.
Some major organizations have managed to manage such systems on their own, such as the United Nations or Cornell University in New York, which relies on water from Lake Kayuga.
But for their bigger part, these systems require a lot of coordination between many stakeholders, Riahi said.
“We know that it is technically possible and we know that there are actually many cases that also prove the economy,” said Rob Thornton, president of the International Regional Energy Association that helps to develop regional cooling and heating networks.
“But this requires someone, an agent, whether it is a champion, a city or utility or someone, to take the set of the market,” he said.
“The challenge is simply the collection and summary of customers to the point where there is enough where the risk can be managed,” Thornton said.
He cited Paris as an example that uses the Seine River to control the largest water-based cooler in Europe.
These networks allow reduced use toxic substances such as cooling and reduce the risk of leaks.
And they avoid hot air emissions – as climate units are worn – in cities that already withstand heat waves.
But hot water from the cooling units, when thrown back into rivers and other water bodies, is dangerous for water ecosystems, environmentalists say.
“This challenge is quite small, compared to ejection from nuclear power plants,” Riahi said, adding that the problem can be resolved by determining a moderate border of that water.
US/ICO/EML/DW/JBR