Data center heat recovery

The heat recovery from data centers represents one of the main challenges in improving the sustainability of digital infrastructure. During their operation, data centers generate significant amounts of heat, which is often dissipated into the environment via traditional cooling systems. However, with advancing technologies, this heat can be transformed from waste into a resource, opening new opportunities for the sector. Considering that data centers account for 1% of global energy demand, consuming 200 TWh annually, and that data traffic grows by 61% each year, energy efficiency and emissions reduction are imperative. Currently, these facilities contribute 191.4 million tons of CO2 emissions, highlighting the need for innovative solutions such as heat recovery.

Fabio Poletto, General Manager of HiRef, emphasizes how HiRef is addressing the challenge of heat recovery in data centers through innovative and sustainable solutions, focused on optimizing temperature management. Data centers, known for their high energy consumption and heat dissipation, generate temperatures ranging from 20°C to 55°C, which are considered low for many industrial applications.
The use of systems such as hot and cold aisle containment within server rooms, along with the ongoing technological improvements in servers, is steadily increasing operating temperatures. With the advent of liquid cooling and high-density computing applications, especially for AI, working temperatures may rise further. However, they remain unsuitable for direct exploitation in most industrial, civil, and residential applications.

HiRef has developed and continues to innovate products aimed at optimizing energy use and repurposing heat that would otherwise be wasted. Examples include high- and ultra-high-temperature heat pumps, such as the XVA and KVW models, which elevate the low-temperature heat from data centers to levels suitable for community use. HiRef’s heat pumps utilize low-impact refrigerants and can raise temperatures up to 90°C, making them ideal for district heating networks, residential facilities, and industrial processes such as building heating or food product drying. These technologies address the growing market demand for improved energy efficiency and reduced CO2 emissions.

HiRef is committed to adopting systems that not only optimize the energy consumption of data centers but also transform them into providers of thermal energy. The heat can be made available for applications in the immediate vicinity of IT infrastructures, such as hospitals and sports centers, or integrated into an Energy Loop District concept. This creates a more circular and sustainable energy system, where heat is reintegrated into the energy cycle instead of being wasted.

Poletto underscores that heat can no longer be considered a waste product to discard. "We can no longer afford to treat heat as waste," he states. "It is a resource that can be efficiently used to heat buildings, power industrial processes, and contribute to decarbonizing the industrial system, paving the way for a more sustainable future—particularly for data centers, whose impact on electricity consumption is significant."

This vision extends beyond technology. The regulatory framework is also evolving, encouraging the integration of data centers into energy networks. Countries like Finland and Norway have already introduced regulations that incentivize the use of heat produced by data centers to power district heating networks and other urban infrastructure. These regulations may soon spread to other European nations, promoting a distributed energy model where recovered heat is used as a primary resource.

The data center industry cannot be guided solely by energy metrics like PUE (Power Usage Effectiveness), which focuses only on the internal energy consumption efficiency of data centers. It is crucial to introduce new metrics, such as ERE (Energy Reuse Effectiveness) and ERF (Energy Reuse Factor), which account for recovered and reused heat, providing a more comprehensive view of infrastructure sustainability.

This approach paves the way for an additional business model in the data center sector, where heat recovery and reuse become central. It is not just about reducing environmental impact, but about transforming data centers into key players in the energy transition, integrating them into urban infrastructure and leveraging their potential to create a more sustainable and innovative energy network.