Data centers: when digital technology transforms a city

As the tangible part of the digital world, data centers are flourishing on the outskirts of cities. They are promoted by elected representatives, sometimes contested by locals, and are not yet well-regulated, raising new social, legal and technical issues. Here is an overview of the challenges this infrastructure poses for cities, with Clément Marquet, doctoral student in sociology at Télécom ParisTech, and Jean-Marc Menaud, researcher specialized in Green IT at IMT Atlantique.

On a global scale, information technology contributes to almost 2% of global greenhouse gas emissions, which is as much as civil aviation. In addition, “The digital industry consumes 10% of the world’s energy production” explains Clément Marquet, sociology researcher at Télécom Paristech, who is studying this hidden side of the digital world. The energy consumption required for infrastructure to run smoothly, under the guise of ensuring reliability and maintaining a certain level of service quality, is of particular concern.

With the demand for real-time data, the storage and processing of these data must be carried out where they are produced. This explains why data centers have been popping up throughout the country over the past few years. But not just anywhere. There are close to 150 throughout France. “Over a third of this infrastructure is concentrated in Ile-de-France, in Plaine Commune – this is a record in Europe. It ends up transforming urban areas, and not without sparking reactions from locals,” the researcher says.

Plaine Commune, a European Data Valley

In his work, Clément Marquet questions why these data centers are integrated into urban areas. He highlights their “furtive” architecture, as they are usually built “in new or refitted warehouses, without any clues or signage about the activity inside”. He also looks at the low amount of interest from politicians and local representatives, partly due to their lack of knowledge on the subject. He takes Rue Rateau in La Courneuve as an example. On one side of this residential street, just a few meters from the first houses, a brand-new data center was inaugurated at the end of 2012 by Interxion. The opening of this installation did not run smoothly, as the sociologist explains:

“These 1,500 to 10,000 m² spaces have many consequences for the surrounding urban area. They are a burden on energy distribution networks, but that is not all. The air conditioning units required to keep them cool create noise pollution. Locals also highlight the risk of explosion due to the 568,000 liters of fuel stored on the roof to power the backup generator, and the fact that energy is not recycled in the city heating network. Across the Plaine Commune agglomeration, there are also concerns regarding the low number of jobs created locally compared with the property occupied. It is no longer just virtual.”

Because these data centers have such high energy needs, the debate in Plaine Commune has centered on the risk of virtual saturation in electricity. Data centers store more energy than they really consume, in order to deal with any shortages. This stored electricity cannot be put to other uses. And so, while La Courneuve is home to almost 27,000 inhabitants, the data center requires the equivalent of a city of 50,000 people. The sociologist argues that there was no consultation of the inhabitants when this building was installed. They ended up taking legal action against the installation. “This raises the question of the viability of these infrastructures in the urban environment. They are invisible and yet invasive”.

Environmentally friendly integration possible

One of the avenues being explored to make these data centers more virtuous and more acceptable is to integrate environmentally friendly characteristics, hooking them up to city heating networks. Data centers could become energy producers, rather than just consumers. In theory, this would make it possible to heat pools or houses. However, it is not an easy operation. In 2015 in La Courneuve, Interxion had announced that it would connect a forthcoming 20,000 m² center. They did not follow through, breaking their promise of a change in their practice. Connecting to the city heating network requires major, complicated coordination between all parties. The project was faced with reluctance by the hosts to communicate on their consumption. Also, hosts do not always have the tools required to recycle heat.

Another possibility is to optimize the energy performance of data centers. Many Green IT researchers are working on environmentally responsible digital technology. Jean-Marc Menaud, coordinator of the collaborative project EPOC (Energy Proportional and Opportunistic Computing systems) and director of the CPER SeDuCe project (Sustainable Data Center), is one of these researchers. He is working on the anticipation of consumption, or predicting the energy needs of an application, combined with anticipating electricity production. “Energy consumption by digital technologies is based on three foundations: one third is due to the non-stop operation of data centers, one third is due to the Internet network itself” he explains, and the last third comes down to user terminals and smart objects.

Read on I’MTech: Data centers, taking up the energy challenge

Since summer 2018, the IMT Atlantique campus has hosted a new type of data center, one devoted to research, and available for use by the scientific community. “The main objective of SeDuce is to reduce the energy consumed by the air conditioning system. Because in energy, nothing goes to waste, everything can be transformed. If we want the servers to run well, we have to evacuate the heat, which is at around 30-35°C. Air conditioning is therefore vital” he continues. “And in the majority of cases, air conditioning is colossal: for 100 watts required to run a server, another 100 are used to cool it down”.

How does SeDuCe work? The data center, with a 1,000-core or 50-server capacity, is full of sensors and probes closely monitoring temperatures. The servers are isolated from the room in airtight racks. This airtight confinement makes it possible to optimize cooling costs tenfold: for 100 watts used by the servers, only 10 watts are required to cool them. “Soon, SeDuCe will be powered during the daytime by solar panels. Another of our goals is to get users to adapt the way they work according to the amount of energy available. A solution that can absolutely be applied to even the most impressive data centers.” Proof that energy transition is possible via clouds too.

Article written by Anne-Sophie Boutaud, for I’MTech.