Historic buildings open their doors for Heritage Days. Behind the scenes, connected objects allow them to modernize. Explanations with Aurélien Blaise, manager at the manufacturer NodOn, who has supervised several heritage-related projects.
JDN. Heritage Days are held on September 17 and 18, 2022. Whether in museums, castles like Versailles, or sites classified as Historic Monuments, the IoT is becoming more and more present. What are the benefits of technology for historic sites?
Aurelien Blaise. Historic buildings are, by definition, old sites that are not up to standard and often constitute veritable thermal sieves. By being wireless and batteryless, IoT sensors allow their managers to modernize them without touching the work or suffering a service interruption. This is what decided the municipality of Angers to automate its Town Hall. They wanted to equip the building with electric blinds, especially for the wedding hall, but they were afraid of having to cut holes in the wall. The IoT has been key.
How did this project go?
We installed around sixty modules in the blinds to make them connected, as well as around sixty switches associated with them, glued to the wall. A dozen temperature sensors communicate with them to lower them in hot weather, for example. Six control units in the building allow them to be controlled remotely. The installation took us less than a week, the configuration took the same time. For users, IoT technology is transparent, they do not realize that the installation diverges from the wired one, so getting started is very simple. This allows the town hall of Angers to automate the management of blinds every morning. The feedback is positive.
In general, what are the constraints of these historic buildings?
The main challenge to be met concerns the thickness of the stone walls. This specificity must be taken into account for radiofrequency, which requires a certain expertise. It is therefore not within the reach of all installers. Care must be taken that the devices do not interfere with each other, that they are all within range of the control unit controlling them, and that they do not all communicate at the same time. It is therefore necessary to favor low-frequency protocols. NodOn uses the EnOcean protocol operating at the frequency of 868 MHz. The products have multi-directional antennas, we configure them to act as a signal repeater.
Is the cost therefore higher compared to other projects in different sectors?
On the contrary, by avoiding work in the structure, and therefore to drill the walls, pull cables, redo the masonry… the IoT allows us to offer quotes half the price. The question may arise for the design, because the managers want the sensors to blend into the decor. Again, the price is not more important because with open and interoperable technologies, there is a large number of manufacturers and therefore a wide choice in the catalogs. Enocean technology, for example, lists more than 520 manufacturers, some of which offer sensors with a look similar to steel, stone or even the shape of Darth Vader.
What market opportunities does the historic buildings sector represent for IoT?
Managers of historic buildings do not necessarily think of the IoT, but the technology responds perfectly to their uses. The market opportunities are therefore significant. The requirement of the sector also makes it possible to refine the capacities of these IoTs. To give an example, we equipped the Carnavalet museum in Paris, before its reopening to the public in November 2020, to automate the management of air conditioning and heating. To monitor the temperature and the hygrometry in order to have a good conservation of the tables, it was necessary to have a precision much higher than the level of the sensors generally used in the smart building. This level of precision will drive demand and pave the way for new uses.
Aurélien Blaise has been Customer Experience and Satisfaction Manager since 2015 at the French connected object manufacturer NodOn. He has supervised numerous client projects, including those for historic buildings, such as the Hôtel de ville in Angers or the Carnavalet museum in Paris.