Decarbonisation through heat recovery from data centres: A2A and Equinix launch a strategic partnership in Milan

In the first half of 2026, Rome experienced one of its most significant rainfall records since January, marking a new high in precipitation levels over the past six years. From January to early June, the city recorded 486.20 millimeters of rain—equivalent to approximately 490 liters per square meter. This figure surpasses the average rainfall during the period from 2020 to 2025 by more than 62.7%. However, this record does not fully reflect the city's overall water security situation. The year has also seen periods of extreme dryness, particularly in April, when only 23.70 millimeters of rain fell, with nearly two weeks passing without any precipitation. On January 5th alone, 40 millimeters of rain were recorded, which exceeded the total amount that fell throughout the entire month of April. The phenomenon reflects a broader shift in Rome’s climate patterns, according to a synthesis report issued by the Appennino Centrale Basin Authority (Aubac). This document highlights how the new climate is characterized by greater irregularity rather than simply increased temperatures or rainfall. Periods of heat and drought alternate with brief but intense weather events, often leading to flooding, erosion, and damage without effectively replenishing groundwater reserves, springs, or deep reservoirs. Such conditions challenge traditional methods of managing water resources, emphasizing the need for adaptive strategies that consider both intensity and timing of precipitation. One notable event occurred on June 3rd, when a tornado struck the northern-eastern quadrant of the capital. Within hours, 25 millimeters of rain fell, peaking at 19.5 millimeters per hour. This volume was higher than the total rainfall recorded in the entire month of April and almost equal to the monthly total for May. The storm caused typical urban impacts, including fallen trees, disrupted roadways, flooded subways and streets, damaged vehicles and businesses, and disruptions to public transport. Schools, markets, and essential services faced critical challenges as a result of these severe weather conditions. According to Aubac’s report, the most relevant aspect of the current situation is not just the intensity of individual events but their placement within a larger trend. In the first five months of 2026, Rome had 38 days of rainfall, slightly fewer than the 37 days recorded in 2025. However, the quantity of water falling on each day was significantly higher. The average daily rainfall intensity rose from about 7.5 millimeters in 2025 to around 13 millimeters in 2026. Days with precipitation exceeding 10 millimeters increased from nine to sixteen. Thus, while it did not rain more frequently, it rained much more intensely. Marco Casini, general secretary of the Appennino Centrale Basin Authority, explains that extreme drought and heavy rainfall are two sides of the same climatic coin. He emphasizes that the new climate alternates between hot spells, dry periods, and brief, violent precipitation events that can flood areas without genuinely replenishing underground water reserves. Therefore, water security must now be managed by considering factors such as timing, intensity, capacity for accumulation, infiltration, and vulnerability of infrastructure networks—not merely based on annual rainfall totals. The situation in Rome exemplifies this concern: the city not only experienced a peak temperature of 39.3°C but also endured a prolonged period where maximum temperatures averaged five degrees above the decade-long mean. This persistent heat signals a growing problem: the heat is not only more intense but also longer-lasting, arriving earlier and increasing evaporation rates, water consumption, and energy demand in cities. Meanwhile, in a separate development, A2A, Italy’s second-largest utility company, has accelerated efforts toward sustainability by entering into a strategic partnership with Equinix, a global leader in digital infrastructure. This collaboration aims to recover and utilize thermal energy generated by data centers, contributing to the decarbonization of urban environments. Through this initiative, A2A will increase the power output of district heating systems in Milan by 20%, leveraging recovered heat from Equinix’s data center located in Settimo Milanese. This project will enable the recovery of approximately 225 gigawatt-hours of thermal energy annually, enough to meet the heating demands of over 21,000 households and avoid emissions equivalent to the absorption capacity of roughly 220,000 trees. The initiative represents a significant step forward in circular economy practices applied to digital infrastructure in Italy. The partnership involves Equinix designing and operating a system to export heat from its campus, working with stakeholders—including clients whose servers generate the heat—to make this thermal energy available for distribution. The recovered heat will be transferred to an Energy Center developed by A2A near the site, where it will be converted using four large-scale heat pumps with a combined capacity of 72 megawatts. Two thermal storage systems, each capable of holding up to 6,000 cubic meters of stored energy, and dedicated infrastructure for transporting the thermal energy to the urban grid will support this process. As a result, the project will contribute to expanding the reach of Milan’s district heating network, allowing the distribution of recovered heat across a wide area, from the city center to peripheral districts, including iconic landmarks such as the Duomo and Palazzo Reale, already served by A2A’s district heating system. Adaire Fox-Martin, CEO and President of Equinix, highlighted that the collaboration with A2A demonstrates how essential digital infrastructure and local sustainability goals can work together harmoniously. She noted that by making locally produced thermal energy available to residents, the initiative eliminates waste and supports Milan’s transition toward a low-carbon future. Similarly, Emanuela Grandi, Managing Director of Equinix Italy, emphasized that excess heat—a byproduct of the computational power required for digital transformation and artificial intelligence—is valuable when redistributed around data centers, creating substantial benefits for communities while reducing the overall energy needed to warm the territory. This project marks a milestone in the European effort to export heat from data centers and sets a precedent for developing a market for thermal energy derived from such facilities, potentially supporting sustainable growth in the sector.