Abstract

Thermomanical energy conversion technologies are poised to play a leading role in nextgeneration energy systems. Such technologies can be used for the recovery, re-use and conversion of “waste heat”, which is widely considered an indispensable element of enhanced industrial efficiency and decarbonisation, but are also well-suited to large-scale and long-durationelectricity storage that is essential for grid stability given the increasing penetration of intermittent renewable generation, while improving the affordability of the whole-energy system transition. In this talk, we will present a diverse range of thermomechanical energy technologies and solutions for the recovery and conversion of waste heat – across temperatures and scales – including heat integration, ORC technology, heat pumps and thermally-driven cooling, alternative heat-to-power technologies, amongst other. We will also review a class of promising bulk energy storage technologies based on thermomechanical principles, which includes: compressed-air energy storage, liquid-air energy storage and pumped-thermal electricity storage. Following this broad presentation of technological options, we will explore the underlying operational principles in each case, the resulting performance and cost characteristics, and compile maps to distinguish the most appropriate options for different sectors and applications. We will address current developments and R&D actions, technology readiness levels (TRLs), costs, broad brush technical and financial characteristics, advantages and disadvantages, as well as share personal knowledge of the challenges faced during the development of selected technologies. Finally, we will attempt to identify rational routes for the selection of the most promising technology(ies) in the specific applications of interest.