Thermodynamic cycles constitute the backbone structure of fossil-fuelled and renewable thermal power systems, refrigerators and heat pumps. In thermodynamic cycles, input energies are converted into output useful energy forms (work or heat) by means of an energy carrier, an inert working fluid, which undertakes cycles of thermodynamic transformations. Power cycles have been dominating global electricity production, and it is expected that refrigerators and heat pumps will represent one of the future major electricity consumers. Improvements of their backbone-thermodynamic structure thus play a crucial role in achieving energy-policy objectives addressing climate change and reducing air pollution, such as the increase of the efficiency of energy use and the deployment of renewable technologies.
To increase the performance of thermodynamic cycles, researches mainly focus on improving their unit operations, optimizing the networking of these components, and optimal selection of a working fluid crossing the whole cycle. Among these possible measures, the choice of the optimal working fluid represents the core of the process of adaptation of conventional fossil-fueled thermal engine configurations to exploit lower-grade renewable and waste heat sources and the primary action to reduce the environmental impact of heat pumps.
Nowadays, only inert working fluids (pure fluids or mixtures) are currently employed. However, despite their optimal selection, the thermal efficiency of these energy conversion systems remains far from the maximum achievable ones, dictated by the Carnot limit.
REACHER proposes to revive an idea which was introduced by Lighthill in the 1950s', which consists in using -instead of INERT working fluids- working fluids being the site of a REVERSIBLE CHEMICAL REACTION. Practically, this means that along each thermodynamic transformation occurring in each unit operation forming the cycle, a chemical reaction evolves, driven by the modification of temperature and/or pressure, and according to chemical equilibrium.
REACHER aims to deepen this unexplored concept and, specifically: to search/design suitable reactive working fluids for different applications (power cycles and heat pumps) and to characterize the thermochemical and thermophysical properties of these fluids; to propose an optimized architecture for the considered thermodynamic cycles; and to validate the impact of using reactive working fluids in a micro power plant.
The expected impact is a groundbreaking increase of the efficiency of these energy systems and/or reduction of their size.