Smart Grids: Electrical networks are changing

Smart grids are the combination of traditional electrical infrastructures and digital technologies. Capable of recording and transmitting millions of data components, these smart grids optimize energy production, facilitate network maintenance, and renew consumption patterns. Here is an overview of the technological innovations behind this revolution…

The term "smart grids" was officially coined in 2005. At that time, the European Commission decided to launch a technological platform, called "Smart Grids", to develop interactions between consumers, suppliers, and electricity managers. The stated ambitions were to support the energy transition and take better account of new consumption patterns. "The term "smart grid" refers to an electricity network using the power of current digital and telecom technologies to manage it globally," explains Yves Barlier, Director of Smart Grids at Enedis. The first European smart grid experiment was launched in Italy in the early 2000s. Using smart meters, the Telegestore project connected nearly 27 million households to the grid, with the aim of avoiding repeated outages. Since then, the deployment of smart grids has accelerated in many countries, including France, one of the largest in Europe.

The eyes and ears of networks

Schematically, the French grid is like a sprawling web with more than 105,000 kilometers of high-voltage lines[1] and more than 1.4 million kilometers of low- and medium-voltage lines[2]. How can we better manage the flows associated with this network? How can incidents be handled and even anticipated? And how to improve maintenance? These are just some of the challenges that RTE (France's transmission system operator) is facing. Thanks to new digital technologies, it is now possible to install sensors at certain strategic points that can provide real-time information on the networks and their operating status. From voltage, power, and cable temperature to the speed at which equipment (such as circuit breakers) is triggered, and even wind speed, these famous sensors provide valuable information to French power grid managers. "Today, we process 100,000 components of data per second, a figure that should reach 1 million in the next ten years," says Michel Béna, Deputy Director of R&D at RTE. At the same time, RTE has begun to deploy automatic systems that centralize all available data at the regional level, and can even make decisions within their perimeter. "Their number will increase from 2 to 10 by 2022, with the ultimate goal of installing 180 throughout France," adds Michel Béna.

Digital intelligence is also being deployed in French houses, thanks to the Linky meter. Some 34 million units of this interoperable system are now installed in houses[3], enabling everyone to carry out what used to be cumbersome and time-consuming procedures: Opening a line, doing a consumption reading, changing a subscription, etc. But Linky also provides valuable data in the event of network incidents. "Thanks to Linky, we know that there is a breakdown somewhere, and we are able to geolocate its origin," says Yves Barlier.

Adapting to the energy transition

Automats, sensors, smart meters…all this equipment will be mobilized to meet the other major challenge of the smart grid: The energy transition. The rise of renewable energies is making the networks management and control increasingly complex. Today, we need to integrate the electricity produced by wind farms and photovoltaic panels, which is intermittent by nature. In addition, consumers are also expected to become producers, with the arrival of positive energy buildings, for example, which are capable of producing more energy than they consume. A situation at the origin of two-way flows, where energy used to flow uninterrupted from power plants to consumers. All this will require flexibility on the grid, to open or close "valves" appropriately, and respect the balance between production and consumption. The power grid is only at the beginning of its "smartification"…

Underground cables under the eye of AI

Without the possibility of visual inspection, how can you tell if an underground cable is showing signs of aging that would require replacement? Recently, Enedis has been using artificial intelligence to help it make its decision. "We collect a large amount of data about the cable, such as the history of nearby substations, incidents from previous years, weather data (temperature can play a role in the aging process), or its technical characteristics, and we deduce through AI the probability that this underground cable will fail," explains Yves Barlier, Director of Smart Grids at Enedis. This new approach allows Enedis to optimize its investments by changing its cables at the right time, neither too early nor too late.

[1] https://www.edf.fr/groupe-edf/espaces-dedies/l-energie-de-a-a-z/tout-sur-l-energie/l-acheminement-de-l-electricite/le-reseau-de-transport

[2] https://federation.ffvl.fr/sites/ffvl.fr/files/180418_Sensibilisation_Enedis.pdf

[3]https://www.cre.fr/Lettres-d-information/la-cre-dresse-un-bilan-positif-du-deploiement-de-linky