combats

Every summer it gets hotter. That is a reality that The AEMET has confirmed for Spain and that also happens in France, as supported by Meteo France. The “micro” solution involves the proliferation of air conditioners in homes, businesses and offices, but that involves a considerable investment and another problem: climate change causes it to be hotter and the hotter it is, the more air conditioners are used. And the more they are used, the more heat they produce and climate change worsens. The fish that bites its tail. Already in 2018, air conditioning and fans represented almost 20% of the total electrical consumption of buildings in the world, according to IEA data. The International Energy Agency collect that global carbon dioxide emissions from air conditioning almost tripled between 1990 and 2022, exceeding one billion tons of carbon dioxide. In cities it is even worse: the urban heat island hits hard. Faced with this reality, Paris has been setting up for decades an answer in the form of infrastructure: a centralized air conditioning for the entire city. The great air conditioning of Paris. Instead of each home or each building solving the thermal problem on its own, the French capital is committed to turning it into an infrastructure such as the sewage network. The system is called Fraîcheur de Paris. The operation it’s simple: a network of buried pipes 120 kilometers long through which very cold water (between 2 and 4 °C) travels to the almost thousand connected buildings. There it absorbs its heat with an exchanger and is cooled again to the 15 production and storage plants. How does it get cold there? With the water of the Seine River as a thermal sink. Of course, the water from the river and the system never mix. This system allows the system to take advantage of the natural temperature of the river to cool without additional electrical consumption in cold seasons. To manage peak demand without installing more plants, the system stores cold at night, when electricity is cheaper and the environment is colder. At that time, the tanks accumulate the cold with ice and release it during the hottest hours of the day, which reduces costs and improves performance. The map of the Fraîcheur de Paris. Fraicheur of Paris Why is it important. Faced with a global problem of rising temperatures, addressing it communally is better than letting everyone go to war on their own in terms of efficiency and use strategy. The numbers back it up: the EU Covenant of Mayors details that the network achieves more than 100% energy efficiency, 35% less electricity, 90% less refrigerant emissions and 50% less CO₂ compared to equivalent autonomous installations. On the other hand, the operating system of standard air conditioning units (with a compressor outside) worsens the problem and adds it to a vicious circle: when there is a lot of urban heat, the air conditioners work longer hours, which increases carbon dioxide emissions and dumps more waste heat into the street, causing the ambient temperature to rise. By directing all that heat into the Seine instead of expelling it into the streets, the network interrupts that cycle. Context. The heat in Paris is not a distant problem: it is already here, as advanced by the official French meteorological agency, which estimates a warming of +2.7 °C in France by 2050, at which time heat waves, droughts and floods will be more frequent and intense. By then, infrastructure should be prepared to withstand them. A couple of examples: Zaragoza is preparing a work against floods and Valencia more of the same. Paris does the same in the face of heat. Thus, in October 2023 he organized “Paris at 50 °C” (Paris at 50 °C), an exercise in which two neighborhoods participated in a crisis simulation in the form of a heat wave. In this futuristic and probable scenario, the cold stops being a luxury typical of hotels and shopping centers and becomes something of a basic necessity. In detail. The system was born as an association of several merchants in the late 70s to air condition their premises, becoming the prelude to a planned municipal project. Back in 1991 there was public service concession to Climespace, a subsidiary of ENGIE, for 30 years. Since 2022 its management is carried out by a joint venture public – private formed by ENGIE and the Autonomous Administration of Parisian Transport. It has a 20-year exploitation contract that covers production, storage, transportation and distribution of cold for a projected value of 2.4 billion euros. This urban air conditioning system has a signed expansion plan: The current concession agreement has among its commitments to extend the network by an additional 158 kilometers, 20 new production plants. The idea is to cover all neighborhoods in Paris and reach more than 3,000 subscribers, including more small businesses, hospitals, daycares, nursing homes, such as explains Raphaëlle Nayralthe general secretary of the Fraicheur de Paris. Yes, but. The Fraicheur de Paris is designed for the French capital and works well there, based on operating numbers and growth expectations, but that does not imply that it is an exportable model for all cities. In fact, it needs three conditions that Paris does meet: a high population density that justifies the investment in buried pipes, a river with sufficient flow to function as a heat sink, and a local administration with the capacity to sign contracts of that size and duration. On the other hand, and despite its expansion, the network still covers only part of the city, so the benefit is only for a part of the population: if everything started in the 90s and a major expansion is expected for 2042, it is clear that it is not an easy project, nor a cheap one, nor one that can be done overnight. In Xataka | Paris has managed to calm its traffic. Now he needs a much more difficult thing: getting his birds back. In Xataka | AEMET … Read more