It takes a proliferation of data centers to serve the growing computing needs of the Internet, and all those servers churning away create plenty of heat. Might some of that heat be harnessed and used for residential or commercial heating? The emergence of district heating systems, which provide thermal energy to multiple buildings from a single source, demonstrates the approach has broad possibilities.
Air-cooled chillers and air-handling units used to cool data centers are like the technologies that cool residences and businesses. They just operate on a larger scale and require a higher degree of resilience and redundancy to ensure data center servers operate without interruption.
District heating system
The law of physics dictates that the energy you put into a data server will come out as heat, and heat is a byproduct of data center cooling systems. Rather than exhaust that heat into the outside environment, how can it be captured and channeled into a district heating system to heat water and/or to provide warmth to homes and businesses in the same neighborhood as the data center?
Law of physics dictates that the energy you put into a data server will come out as heat
Mitsubishi Electric designs engineered solutions that both cool data centers and generate heat output that can be captured for district heating applications. “We want to capture the heat and repurpose it for someone else to use,” says Simon Prichard, Product Strategy Manager for Engineered Solutions for Mitsubishi Electric. Reusing wasted heat from data centers can help to decarbonize heating.
United Kingdom's Energy Act 2023
An additional heat pump can be used to increase the “low-grade heat” generated by a data center to the temperature needed for district heating. Alternatively, district heating systems might be upgraded to accommodate the lower-temperature heat from data centers.
| Additional heat pump can be used to increase the “low-grade heat” generated by a data center. |
The United Kingdom and other governments globally are promoting the creation of district heating networks. Legislation such as the United Kingdom's Energy Act 2023 identifies areas within England where certain new and existing buildings will be required to connect into district heating networks. Legislation is pushing developers toward district heating and away from the use of fossil fuels.
District heating applications
Water cooling is a developing technology for data centers, which mostly use air-cooling systems
In November 2023, the UK government awarded £36 million to a district heating system in West London that will share data center waste heat with up to 10,000 new homes. Hot air from a data center can provide some of the energy needed for a district heating system, and water-cooling systems can provide even more. Water cooling is a developing technology for data centers, which mostly use air cooling systems.
Cooperation is needed to realize the scenario of capturing the heat from data centers for district heating applications. Government legislation can drive requirements to embrace the approach, but the multiple involved parties, including data center operators and the architects and engineers creating nearby communities, must also cooperate.
Greater ESG goals
Energy must be reused in the geographic area immediately surrounding the data center for the scenario to be financially viable. In an industrial estate, for example, the excess heat could be used for nearby farming; the reuse is not restricted to domestic or residential applications. The various parties tend to be “siloed,” so a concerted effort of “joined-up thinking” is needed to bring all the parties to the table to enable such a system.
| Construction of new data centers is accelerating, and the centers are getting larger. |
Construction of new data centers is accelerating, and the centers are getting larger. Currently, 4 or 5% of total electricity output is used by data centers, and ways to reuse that energy are a growing priority for ethical companies in the data center market. Large companies that use data centers are drawn to the district heating scenario to achieve greater ESG (Environmental, Social, and Governance) goals. Moving forward, it behooves everyone to think of data centers as not just generating data but as energy centers generating sustainable energy.
Mitsubishi Electric’s products
MEWALL mixes high version with energy efficiency, space optimization, and cost-effectiveness
“We live in a connected world, and we need data centers,” says Prichard. “The world won’t work without them, but many people don’t know what a data center is and how much we rely on them. Society doesn’t realize how embedded they are.”
Among Mitsubishi Electric’s products for the data center market is the MEWALL air handling unit, a “wall” of fans with built-in controls, valves, and filters that are mounted alongside a suite of data servers. MEWALL combines high performance with energy efficiency, space optimization, and cost-effectiveness. Water circulates inside the fans, using cold water produced by a chiller.
View of the MEWALL system
Smaller data center needs can be addressed using technology such as Mitsubishi Electric’s indoor s-MEXT high-precision air conditioner connected to a Mr. Slim R32 Power Inverter outdoor unit. The indoor unit is customized to the client’s requirements for use in a data center.
At the Data Center World trade show in London in March, Mitsubishi Electric used virtual reality (VR) to provide attendees with a simulated view of the MEWALL system. Given the dimensions of 4 by 2.3 meters, transporting the system to the show presented prohibitive cost and logistical challenges.