Knowledge is cold …

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Data center, an environment that “issue challenges” to modern refrigeration

… and energy-eating. They are the two issues that lead a sector, the one of data centers, to be an important side of the refrigeration world, but not sufficiently known and divulged, yet. A theme that depends on the technologies adopted, on their engineering and organizational modality and on factors that also concern the envelope where the data center is hosted.

What enables the global communication system? The net. However, the latter draws information from refrigerated “sanctuaries”, data centers. They are the real heritage that makes the net significant. Therefore, the world of redundant servers that house database, sites, archives recovered from the analogue world, data stored according to organic logics or non-, is the planet’s real intellectual heritage, with its pros and cons.

Besides, if the infrastructure that allows the circulation of these information is necessary, we discover almost stealthily that these bytes are much more exacting than humans in the ambit of temperature and relative humidity rate, needing also a very challenging filtration of the environmental air, but we now analyse the most “trivial” matter, the temperature management.

Then the first question to be asked is – beyond the percentage incidence – what is the work we are carrying out in Italy on this sector, what are the variables to be ruled, what the consequences that the ecologic transition is determining in this field.

Base coordinates
Data centers are physical structures where are hosted large servers, data processing machines, uninterruptible power supplies and support equipment of information systems. They are engine rooms constantly in operation, 24 hours a day, and they handle and process enormous quantities of digital processes and information.

Consequently, they consume large amounts of energy and resources that the most attentive organizations try gradually decreasing, to optimize costs and to reach, in the meantime, noxious emissions for the environment that are close to zero as much as possible. It is a target highly in vogue also in environments that are “distant” from regulatory binds like European ones, because many of these structures belong to big brands or multinationals that make their Corporate and Social Responsibility image a feather in the cap. Ultimately, this requires that the data center design is accomplished according to severe efficiency criteria, increasingly based on renewable energy sources (and here we are already introducing an “extra-plant engineering” concept that concerns the integration with the choices of primary energy to be used”).

However, it is easy to deduce that one of the primary criticalities that can be associated to data centers is the heat that is generated by the manifold powerful machines hosted in their interior: in fact, in case of an excessive temperature, the operation of information equipment is affected, with huge damages to the whole infrastructure. For this reason, each data center provides for a system of heat cooling and extraction in its interior, more or less structured.

From an approximate but highly plausible calculation, we know that the heat dissipated by IT systems represent about one third of the energy overall absorbed: this therefore determines the absolute priority of the energy consumption and of the environmental impact that derive from their use, to the extent of resulting in the need of developing more and more efficient conditioning solutions, connecting the functional aspects of business continuity with economic ones of correlated costs.

Options, strong and weak points
The management of the temperature factor has always implied the use of systems that sought the utmost efficiency and therefore direct expansion systems, based on the use of synthetic cooling gases with high refrigerating potential, were deployed, but today we can state that the building of these systems is subjected to three different elements that make the choice of this refrigerant typology less and less simple.

First of all, the dimensional growth of these environments, which asks the potential question of using systems with alternative gases (with cascade plants) that – on the size of new giant data centers – can prove to be more efficient and efficacious, according to the issue connected with the flammability of the new generation of synthetic gases, which limits their use under complex conditions from the point of view of ATEX regulation and, third, the quickly incoming term for the elimination from the market of refrigerants with such GWP as to make them considered as climate-impacting.

The choice of turning to cascade systems that exploit refrigerant fluids based on natural molecules is however subjected to the second important remark, i.e. a highly efficient design, which exploits also the least “refrigerating” and more “aeraulic” solutions of heat recovery.

A really giant technology and design issue, which we intend to study in-depth due to its growing relevance in the economic impact and in the development repercussions that it will cause in our refrigeration world.