Introduction and moderation
Energy harvesting from vibrations, elastic/acoustic waves, and fluid-structure interactions
Research efforts in the domain of energy harvesting for low-power devices aim to enable self-powered systems, such as wireless sensor networks and wearable electronic components, toward minimizing the maintenance costs and chemical waste of using conventional batteries. This talk will review our recent investigations on energy harvesting from dynamical systems by using piezoelectric conversion. Various sources of energy will be considered, such as vibrational/kinetic energy, elastic and acoustic waves, and fluid flow. Following basic piezoelectric energy harvesting concepts that employ the linear resonance phenomenon, we will discuss how to exploit nonlinear dynamics to create wideband energy harvesters and overcome the frequency bandwidth limitation of linear harvesters. Metamaterial and phononic crystal concepts and their leveraging in the harvesting of structure-borne and air-borne waves will also be shown with demonstrations. Examples will then be given on the harvesting of aeroelastic and hydroelastic vibrations by means of piezoelectric structures that are excited under fluid flow. Classical flutter and axial limit cycle oscillations in the regular and inverted piezoelectric flag cases will be presented. Underwater vortex-induced vibration energy harvesting will also be addressed with an example on a multifunctional bio-inspired piezoelectric robotic fish excited by water flow in the wake of a bluff body. Finally, wireless ultrasonic power transfer will be discussed as a method of piezoelectric power delivery to inaccessible devices.
High energy efficiency perovskite based solar cells
Over the past decade, the power conversion efficiency of lead halide perovskite based solar cells has increased at an unprecedented rate such that it is now over 25 % for single junction and 29 % for tandem with silicon. In this talk, after a general introduction of the perovskite photovoltaic (PV) principles, I will introduce different PV applications including Perovksite materials. These developments are done in CEA laboratories located in the national institute for solar energy (INES), in the French alps. The technologies we develop are suitable for different uses, demonstrating the versatility of Perovskite materials. I will introduce Silicon/Perovskite tandem solar cells for grid-on applications, single junction flexible cells for building integrated PV (developed in the framework of the European project Apolo), space applications, energy harvesting of IoT objects and energy supply of solar fuel systems.
Urban & renewable energy producers
Unéole proposes a new mixed production floor including urban wind turbines covered with a photovoltaic rooftop. Unéole realises energy studies before each renewable energy production project in order to verify its interest and control its profitability. These studies allow us to identify the most interesting installation areas.