Travail de fin d'études et stage[BR]- Travail de fin d'études : Contribution to the development of a 10kWe-scale thermally integrated Carnot battery based on a reversible organic Rankine cycle[BR]- Stage

Abstract

This master thesis reports the contributions made to the RenewBat project during the end-of-study internship. The project focused on building and operating a 10kWe-scale thermally integrated and reversible ORC-based Carnot battery demonstration plant con- nected to the district heating of the University of Liège. This type of system can be built with different architectures. The first part of this work justifies the technological choices made on the basis of previous laboratory experiments and the literature. The sizing and selection of components are also described. This sum- mary will help the scientific contributors to better grasp the project, and will provide a basis for discussion on the design of similar systems. A significant part of this work consists in rigorously redefining the project’s objectives and the requirements needed to achieve them. Ultimately, the system will have to be fully automated and meet industry requirements, so that the results can make a significant contribution to the research field. The KPIs that can be achieved and that will contribute to the maturity of the technology are identified. Possible improvements to optimize these KPIs over the duration of the project are outlined. Based on the architectural choices and the constraints defined by the project objectives, the final design is proposed. Particular attention is paid to circuits sizing to maximize components and overall system performance. Opperability and safety constraints are also taken into account. Sensors are discussed in order to minimize costs while enabling optimal control, which will be the key to achieving the best system performance. An original off-design modeling method is proposed for the system. This development follows the control requirements identified. Particular attention is paid to auxiliary con- sumptions (water pumps, dry cooler), the efficiency of electric motors, and the physical limits of components, so that the results obtained correspond to a realistic system imple- mented in a significant environment. This model is used to identify tests to be carried out during system installation to obtain data that cannot be collected once the demon- stration plant is operational. In the medium term, it will provide a basis for fine-tuning the system. In the long term, once the model is fully calibrated, the KPIs can be extrap- olated to cover the entire operating range of the system, enabling control optimization. The final results of the project will be used to assess the benefits of the technology for identical configurations and power levels. Application to cases varying in one of these two characteristics is not trivial, however, and will require additional modeling work. A systematic methodology for selecting suitable cases for Carnot batteries integrating waste heat recovery in industry is proposed.