Bogdan Stefanescu, Expert IoT

Published on 09 August 2023

Smart home, predictive maintenance, smart metering (taking readings or measurements over a wide area: meter readings, network management, etc.). With 75 billion connected objects by 2025, the IoT represents a major challenge.

 In 2016, SPIE ICS in France set up a dedicated Chair with INSA Lyon. The aim is to imagine the world of tomorrow. Portrait of Bogdan Stefanescu, in charge of one of the four research streams: Smart Anything, how do we power billions of connected objects?

Ten years ago, Bogdan Stefanescu left INSA Lyon and came to work for SPIE. Now he has returned to his roots, taking up the IoT Chair. “I joined SPIE as a network engineer, then I moved into an architect role and became manager of a centre of excellence. But the technical side has always been my passion, says Bogdan. That’s why I got involved in the IoT Chair.” One of the major topics that Bogdan is working on is how to power connected objects, and in particular ‘no-battery’ technology. ”It’s impossible to even contemplate the IoT without solving the limitations of external power sources for autonomous objects in large-scale deployments while respecting the environment.”

Today, 44% of the cost of an IoT system relates to maintenance. Between now and 2025, the deployment of 5G will allow connectivity which is 100 times faster than today, along with the connection of 75 billion objects in all areas: smart city, home automation, industry, healthcare, etc. This means the same number of batteries as objects. The problem is that their environmental footprint is significant. This also raises the question of the cost of equipment maintenance, which can be up to 44% of the cost of the IoT system.

Allowing at least some of these devices to operate without a battery therefore has two major benefits - ecological and financial. ”SPIE has long been committed to the green economy and energy efficiency. It’s logical that we work with the Chair on solutions which are both promising and that our clients are waiting for, such as wireless power transfer or making use of ambient energy.” According to Bogdan, we must adopt an intelligent approach to system development and eco-design must be at the heart of research activities. He is convinced that “thinking must be global”.


Senior Lecturer at INSA Lyon

3 questions to Guillaume Villemaud, Senior Lecturer at INSA Lyon

Why is the powering of connected objects a major focus of research?

When we say ”connected objects”, we mean wireless communications in the vast majority of cases. Yet, wireless technology consumes more energy than wired. As the move towards connected objects is bound to accelerate, it is essential that we reduce this consumption. Especially given that batteries are not the ideal solution, from both a manufacturing point of view and a recycling or maintenance point of view.

What solutions do we need to reduce this consumption?

At INSA, our research is focused on two possible areas: firstly, make it so that systems are off most of the time and only turned on when they are needed. We call this the “wake-up radio” principle. The other area of focus is to recharge batteries using ambient energy harvesting, in particular using electromagnetic waves. Should ambient energy not be sufficient, we need to develop wireless energy transfer, meaning a dedicated energy source which powers the object remotely

How are you working with SPIE?

Our partnership is win-win: we submit ideas for development or research projects, and SPIE comes back with possible applications and usage scenarios. This means we can work on real-world scenarios. For me, this partnership only has positives. We really are in a relationship of exchange and emulation, and I really like that!

Projections for 2025


connected objects

20 %

of global electricity consumption will be for digital devices

1 100 TWh

annual electricity consumption by all connected devices, according to the International Energy Agency (*TWh = terawatt-hour)